HK1164412B - Continuously variable transmission - Google Patents

Description

Continuously variable transmission

This application is a divisional application based on application No. 200680052482.9 entitled "continuously variable transmission" filed on 2006, 10, 3.

This application claims priority from U.S. provisional application 60/749,315 filed on 9/12/2005, U.S. provisional application 60/789,844 filed on 6/4/2006, and U.S. provisional application 60/833,327 filed on 25/7/2006, the contents of which are incorporated herein by reference.

Technical Field

The field of the invention relates generally to transmissions and more particularly to Continuously Variable Transmissions (CVTs).

Background

Several ways are known to achieve a continuously variable transmission ratio of input speed to output speed. The mechanism in a CVT for regulating the input speed from the output speed is called a variator. In a belt CVT, the variator comprises two adjustable pulleys with a drive belt between them. A single chamber toroidal CVT has two partially toroidal drive discs rotating about an axis, and two or more disk-shaped power rollers rotating on respective axes, with the axes of the power rollers being perpendicular to the axes of the drive discs and sandwiched between the input and output drive discs.

The embodiments of the invention disclosed herein are ball-type variators that utilize spherical speed adjusters (also known as power adjusters, balls, ball gears or rollers), each having a tiltable axis of rotation; the adjusters are distributed in a plane about the longitudinal axis of the CVT. The rollers contact the input disc on one side and the output disc on the other side, one or both of the input and output discs applying a clamping force to the rollers to transmit torque. The input disc applies an input torque to the rollers at an input rotational speed. The rollers transmit torque to the input disc as the rollers rotate about their own axes. The ratio of input speed to output speed varies with the radius of the roller shaft from the point of contact of the input and output discs. The transmission ratio is adjusted by the inclination of the roller shaft relative to the variator axis.

Disclosure of Invention

The systems and methods disclosed herein have several features, no single one of which is solely responsible for all desirable attributes. Without limiting the scope as defined by the appended claims, the more prominent features of certain embodiments of the invention will now be described briefly. After considering this discussion, and particularly after reading the section entitled "detailed description of certain embodiments" one will understand how the features of the systems and methods provide several advantages over corresponding conventional systems and methods.

In one aspect, a continuously variable transmission is described, comprising: a first traction ring; a second traction ring; a plurality of power rollers interposed between and in contact with the first traction ring and the second traction ring, wherein the power rollers are configured to rotate about a tiltable axis; a shift rod nut operatively connected to tilt the axis; and a shift rod coupled to the shift rod nut, wherein rotation of the shift rod causes the shift rod nut to axially translate and tilt the axis.

In another aspect, a continuously variable transmission is described, comprising: a first traction ring; a second traction ring; a plurality of power rollers interposed between and in contact with the first traction ring and the second traction ring, wherein the power rollers are configured to rotate about a tiltable axis; a first torsion spring; and wherein the first traction ring includes a recess adapted to receive and partially house the first torsion spring.

In another aspect, a continuously variable transmission is described, comprising: a first traction ring; a second traction ring; a plurality of power rollers interposed between and in contact with the first traction ring and the second traction ring, wherein the power rollers are configured to rotate about a tiltable axis; an idler wheel in contact with each power roller and radially inward of a contact between the power roller and the first and second traction rings; a main shaft having a central bore, and wherein the idler gear is coaxially mounted about the main shaft; and a shift rod having a threaded end, wherein the shift rod is inserted in the central bore, and wherein the threaded end is substantially concentric with the idler.

In another aspect, a continuously variable transmission is described, comprising: a plurality of spherical power rollers, each power roller adapted to rotate about a tiltable axis; first and second traction rings; an idler wheel mounted about the spindle; wherein each of said spherical power rollers is interposed between said first and second traction rings and said idler in a three point contact; a load cam driver; a first plurality of load cam rollers, wherein the first plurality of load cam rollers are interposed between the load cam driver and the first traction ring; a thrust bearing; a hub shell, wherein the thrust bearing is located between the load cam driver and the hub shell; a hub shell cover; and a second plurality of load cam rollers interposed between the second traction ring and the hub shell cover.

In another aspect, a transmission housing is described, comprising: a hub having a first bore and an integral bottom, wherein the integral bottom has a hub central bore having a diameter less than the first bore diameter; and a hub cap adapted to substantially cover the first bore, and wherein the hub cap has a cap central bore that substantially coincides with the hub central bore when the hub and the hub shell are joined together to form the transmission housing.

In another aspect, a continuously variable transmission is described, comprising: a first traction ring; a second traction ring; a plurality of power rollers interposed between and in contact with the first traction ring and the second traction ring, wherein the power rollers are configured to rotate about a tiltable axis; a load cam driver operatively connected to the first traction ring; a torsion disc adapted to drive the load cam driver; an input drive configured to drive the twist disk; wherein the first and second traction rings, load cam driver, torsion disc and input driver are coaxially mounted about a main shaft of the continuously variable transmission; and a one-way clutch adapted to drive the input driver.

In another aspect, an input driver is described, comprising: a substantially cylindrical hollow body having a first end and a second end; a set of splines formed at the first end; and first and second bearing races formed inside the hollow body.

In another aspect, a twist disk is described, comprising: a substantially circular plate having a central bore and an outer diameter; wherein the outer diameter comprises a set of splines; and wherein the central bore is adapted to receive an input drive.

In another aspect, a power input assembly is described, comprising: an input driver having a first end and a second end, wherein the first end has a set of splines; and a twist disk having a central bore adapted to be connected to the second end of the input drive, the twist disk having a second set of splines.

In another aspect, a load cam driver for a transmission is described, the load cam driver comprising: a substantially annular plate having a central aperture; a set of splines formed within the central bore; and a reaction surface formed on the annular plate.

In another aspect, a shaft for a transmission is described, the shaft comprising: a first end, a second end, and a middle portion; a through slot located substantially in the middle portion; a central bore extending from the first end to the through slot; and first and second knurled surfaces, one on each side of the channel.

In another aspect, a stator plate for a transmission is described, the stator plate comprising: a central bore; a plurality of reaction surfaces arranged radially about the central bore; and wherein the reaction surfaces that are opposite one another are staggered relative to one another about the central bore.

In another aspect, a stator plate for a transmission is described, the stator plate comprising: a central bore; an outer ring; a plurality of connecting extensions extending substantially perpendicularly from the outer ring; and a plurality of reaction surfaces radially disposed about the central bore, the reaction surfaces being located between the central bore and the outer ring.

In another aspect, a stator bar for a transmission carrier is described, the stator bar comprising: a first shoulder and a second shoulder; a waist located between the first shoulder and the second shoulder; a first end adjacent the first shoulder; a second end adjacent the second shoulder; and wherein each of the first and second end portions includes a counter bore.

In another aspect, a bracket for a powered roller leg sub-assembly is described, the bracket comprising: a first stator disk having a first stator disk central bore and a plurality of first stator reaction surfaces arranged circumferentially about the first stator disk central bore, wherein opposing first stator disk reaction surfaces passing through the first stator disk central bore are staggered relative to each other; and a second stator plate having a second stator plate central aperture and a plurality of second stator reaction surfaces arranged circumferentially about the second stator plate central aperture, wherein opposing second stator plate reaction surfaces passing through the second stator plate central aperture are staggered relative to each other.

In another aspect, a shifter for a transmission is described, the shifter comprising: a shift rod having a threaded end, a middle portion, a splined end, and a flange; a shift rod nut having a first central bore adapted to receive the threaded end of the shift rod; and a shaft having a second central bore adapted to receive the shift rod, wherein the shaft includes a counter bore adapted to engage a flange of the shift rod.

In another aspect, a shift lever for a transmission is described, the shift lever comprising: a first end, a middle portion, and a second end; a set of threads on the first end; a pilot end adjacent the set of threads; a set of splines on the second end; a flange between the middle portion and the second end; a neck adapted to support a shift rod retainer nut, wherein the neck is located between the flange and the set of splines.

In another embodiment, a traction ring for a transmission is described, the traction ring comprising: a ring having a first side, a middle portion, and a second side; a set of ramps on the first side; a recess in the intermediate portion, the recess adapted to receive a torsion spring; and a traction surface on the second side.

In another aspect, a torsion spring for use with an axial force generating system is described, the torsion spring comprising: a traveler having a first end and a second end; a first straight portion and a first curved portion on the first end; and a second straight portion and an auxiliary curved portion on the second end.

In another aspect, a loaded cam roller retainer is described for use with an axial force generating mechanism, the loaded cam roller retainer comprising: a loaded cam roller locating ring; and a retaining extension extending from the load cam positioning ring.

In another aspect, an axial force generating mechanism for a transmission is described, the axial force generating mechanism comprising: a traction ring having a first side, a middle portion, and a second side, wherein the first side includes a set of ramps and the second side includes a traction surface; a torsion spring having a first end and a second end; wherein the intermediate portion of the traction ring comprises a groove adapted to receive the torsion spring; and a load cam roller retainer having a retaining extension adapted to mate with the groove of the traction ring to substantially accommodate the torsion spring.

In some aspects, an axial force generating mechanism for a transmission is described, the axial force generating mechanism comprising: a ring having a first reaction surface; a traction ring having a second reaction surface, wherein the traction ring includes an annular groove; a plurality of load cam rollers interposed between said first and second reaction surfaces; a loaded cam roller retainer adapted to retain the loaded cam roller, wherein the loaded cam roller retainer includes a retaining extension; and a torsion spring adapted at least partially between the annular groove and the retaining extension.

In another aspect, an axial force generating mechanism for a transmission is described, the axial force generating mechanism comprising: a hub shell cover having a first reaction surface, the hub shell cover adapted to be coupled to a hub shell; a traction ring having a second reaction surface, wherein the traction ring includes an annular groove; a plurality of load cam rollers interposed between said first and second reaction surfaces; a loaded cam roller retainer adapted to retain the loaded cam roller, wherein the loaded cam roller retainer includes a retaining extension; and a torsion spring adapted to be at least partially received between the annular groove and the retaining extension.

In another aspect, a shifter interface for a transmission is described, the shifter interface comprising: a shaft having a central bore and said counterbore within said central bore; a shift rod having a shift rod flange adapted to be received within the counterbore; and a shift rod retainer nut having an inner diameter adapted to mate with the counterbore to axially constrain the shift rod flange.

In another aspect, a shift rod holder nut is described, comprising: a hollow cylindrical body having an inner diameter and an outer diameter; a set of threads on the inner diameter and a set of threads on the outer diameter; a flange adjacent one end of the cylindrical body; and an extension connected to the flange, the extension adapted to receive a fastening tool.

In another aspect, a shift rod holder nut is described, comprising: a hollow cylindrical body having an inner diameter and an outer diameter; a flange connected to one end of the cylindrical body; and wherein the flange comprises a flange outer diameter having a shaped surface.

In another aspect, a shift rod holder nut is described, comprising: a hollow cylindrical body having an inner diameter and an outer diameter; a flange connected to one end of the cylindrical body; and wherein the flange includes a plurality of extensions adapted to assist in positioning the shifter.

In another aspect, a flywheel for a bicycle is described, the flywheel comprising: a one-way clutch mechanism; a cylindrical body adapted to receive the one-way clutch mechanism; wherein the cylindrical body comprises an inner diameter having a set of splines; and a set of teeth on an outer diameter of the cylindrical body, wherein the set of teeth are offset from a centerline of the cylindrical body.

In another aspect, a hub shell for a transmission is described, the hub shell comprising: a generally cylindrical hollow housing having a first end and a second end; a first aperture at a first end of the housing, the aperture adapted to couple to a hub shell cover; a bottom portion at the second end of the housing, the bottom portion including a first central aperture; a reinforcing rib at a junction between the base and the hub; and a seat adapted to support a thrust washer, the seat being formed in the bottom.

In another aspect, a hub shell cover for a transmission hub shell is described, the hub shell cover comprising: a substantially circular plate having a central bore and an outer diameter; a spline extension extending from the central bore; wherein the splined extension includes a first recess for receiving a bearing, and wherein the outer diameter includes a knurled surface adapted to cut into the hub shell body.

In another aspect, a hub shell cover for a transmission hub shell is described, the hub shell cover comprising: a substantially circular plate having a central bore and an outer diameter; a disc brake fixedly extending from the central bore; wherein the disc brake fixed extension includes a first groove for receiving a bearing, and wherein the outer diameter includes a knurled surface adapted to cut into the hub shell body.

In another aspect, a ball leg assembly for a power roller transmission is described, the ball leg assembly comprising: a power roller having a central bore; a power roller shaft adapted to be mounted within the central bore, the power roller shaft having a first end and a second end; a plurality of needle bearings mounted on the shaft, wherein the power rollers rotate on the needle bearings; at least one spacer between the needle bearings; and first and second legs, the first leg being connected to a first end of the power roller shaft, the second leg being connected to a second end of the power roller shaft.

In another aspect, a leg assembly for transmission shifting is described, the leg assembly comprising: a leg portion having a first bore for receiving one end of a power roller shaft, said leg portion further having a second bore and two leg extensions, each leg extension having a shift cam roller shaft bore; a shift guide roller shaft located within the second bore of the leg portion, the shift guide roller shaft having first and second ends; first and second shift guide rollers mounted on first and second ends of the shift guide roller shaft, respectively; a shift cam roller shaft located in a shift cam roller shaft bore through which the leg extends; and a shift cam roller mounted on the shift cam roller shaft, the shift cam roller being located between the leg extensions.

In another aspect, a power roller for a transmission is described, the power roller comprising: a substantially spherical body; a central bore through said ball, said central bore having first and second ends; and wherein the first and second ends each comprise a sloped surface.

In another aspect, a power roller and power roller axle assembly for a transmission is described, the power roller and power roller axle assembly comprising: a substantially spherical body; a central bore through said ball, said central bore having first and second ends, wherein said first and second ends each comprise a sloped surface; a power roller shaft adapted to be mounted within the central bore, the power roller shaft having a first end and a second end; a plurality of needle bearings mounted on the shaft, wherein the power rollers rotate on the needle bearings; and at least one spacer mounted on the shaft and located between the needle bearings.

In one aspect, a continuously variable transmission is described, comprising: inputting a traction ring; an output traction ring; an idler pulley; a plurality of power rollers contacting the input traction ring, the output traction ring, and the idler, wherein the power rollers each have a central aperture; and a plurality of roller axles, one for each power roller axle, mounted within the central bore, wherein each roller axle includes first and second ends, and wherein the first and second ends each include a counterbore.

In another aspect, an idler assembly for a transmission is described, the idler assembly comprising: an inner liner having a cylindrical body and a cut-out hole through the cylindrical body about an axis perpendicular to a major axis of the cylindrical body; two angular contact bearings mounted on the cylindrical body; an idler mounted on the angular contact bearing; and two shift cams mounted around the cylindrical body, wherein the idler is located between the shift cams.

In another aspect, an idler assembly for a transmission is described, the idler assembly comprising; an inner liner having a cylindrical body and a cut-out hole through the cylindrical body about an axis perpendicular to a major axis of the cylindrical body; two shift cams mounted about the cylindrical body, each shift cam having a shift cam bearing race; a plurality of bearing rollers; and an idler having two idler bearing races, wherein the idler bearing race and the shift cam bearing race are adapted to form an angular surface contact bearing when the plurality of bearing rollers are inserted between the idler bearing race and the shift cam bearing race.

In another aspect, an idler assembly for a transmission is described, the idler assembly comprising: an inner liner having a cylindrical body and a cut-out hole through the cylindrical body about an axis perpendicular to a major axis of the cylindrical body; two shift cams mounted about the cylindrical body, each shift cam having a shift cam bearing race; a plurality of bearing rollers; an idler having two idler bearing races, wherein the idler bearing race and the shift cam bearing race are adapted to form a relieved contact bearing when the plurality of bearing rollers are inserted between the idler bearing race and the shift cam bearing race; and wherein each shift cam includes an extension having a locking key adapted to rotationally constrain and radially position a shift rod holder nut.

In another aspect, an idler assembly for a transmission is described, the idler assembly comprising: a first shift cam comprising a tubular extension, wherein the extension comprises a hole that branches the extension; a first bearing race formed on the first shift cam; a second shift cam mounted about the extension; a second bearing race formed on the second shift cam; an idler having third and fourth bearing races formed on an inner diameter of the idler; and a plurality of bearing rollers, wherein said first, second, third and fourth bearing races together form an angular contact thrust bearing when said bearing rollers are interposed between said bearing races.

In another aspect, a quick release shifter mechanism is described, comprising: a positioning ring; a release key; a back plate adapted to receive the retaining ring and the release key; and wherein the release key and the positioning ring are adapted such that the release key expands the positioning ring when the release key is pushed toward the positioning ring.

In another aspect, a shifter interface for a transmission is described, the shifter interface comprising: a shifter actuator; a shift rod nut connected to the shifter actuator; a back plate adapted to be mounted on a shaft, wherein the back plate is connected to the shifter actuator; and a retaining device located between the shifter actuator and the back plate for axially restraining the shifter actuator.

In another aspect, a power input assembly is described, comprising: an input drive having a first end and a second end, wherein the first end includes a splined surface, and wherein the second end includes at least two torque transmitting extensions; and a torque transmitting key having at least two torque transmitting tabs configured to cooperate with the at least two torque transmitting extensions.

In one aspect, an idler assembly for a CVT includes: a shift lever nut; at least two shift cams; and wherein the shift rod nut is located between the shift cams, the shift cams being substantially adjacent to the shift rod nut. In some such configurations, the shift rod nut provides position control to the shift cam.

In another aspect, a CVT housing may include: a hub shell having a first threaded bore; a hub housing cover having a second threaded aperture adapted to be threaded onto the first threaded aperture; and wherein the hub shell and the hub shell cover each have a central bore for allowing the main shaft to pass through the central bore. The hub shell cover may additionally include a first set of locking slots. In some applications, the housing may have one or more locking tabs having a second set of locking grooves adapted to mate with the first set of locking grooves.

In other aspects, a disc brake kit may include: a fixing plate; a disc brake lining plate; and at least one seal. In some applications, the fixed plate and the disc brake assembly are integral. The retaining plate may be provided with a groove for receiving a roller brake flange.

In some aspects, a load cam profile may have one or more features including a first substantially planar portion and a first radius portion adjacent to the first planar portion. The load boundary profile may also have a second substantially planar portion, wherein the first radius portion is located between the first and second planar portions. In other embodiments, the load cam profile may also be provided with a second radius portion adjacent to the second planar portion; and a third substantially planar portion, wherein the second radius portion is located between the second and third planar portions. The radius of the first radius portion is preferably greater than the radius of the second radius portion. The radius of the first radius portion is at least 1.5R relative to the radius R of the roller used in conjunction with the load cam profile, and the radius of the second radius portion is at least 0.25R and less than about 1.0R.

In one aspect, a hub shell cover for a CVT hub shell includes a generally annular plate having a central bore and a periphery. The hub shell cover may include a set of threads formed on the outer periphery and a set of locking splines formed in the annular plate. The hub shell cover may also have one or more keys for securing components of the CVT. In some applications, the hub shell cover may be provided with a splined flange.

In another aspect, a locking tab for a hub shell and a hub shell cover of a CVT is defined by a thin plate having a plurality of locking grooves, each groove including at least one crest and one gullet, and at least one groove formed in the thin plate. The slots are substantially elliptical in shape, and the foci of the slots are angularly spaced about a central point by a first angle. The locking grooves are angularly spaced about the center point by a second angle. In some cases, the first angle is about half of the second angle. A first focal point of the groove is angularly aligned with a tooth crest of a locking groove and a second focal point of the groove is angularly aligned with a tooth trough of the locking groove, and wherein the tooth crest and the tooth trough are adjacent. In other aspects, a locking ring for a CVT hub shell and a hub shell cover has: a generally circular ring; a plurality of locking splines formed on an inner diameter of the ring; and a plurality of bolt grooves formed at an outer diameter of the ring.

In one aspect, an input driver for a CVT includes: a generally cylindrical body having an inner diameter and an outer diameter; a helical groove on the inner diameter; and a plurality of splines on the outer diameter, wherein not all of the splines are the same size. In another aspect, a power roller shaft includes: a generally cylindrical body having a first end and a second end; a plurality of counter bored holes, wherein each of said first and second ends has a counter bored hole. The power roller shaft may also have one or more grooves on the outer diameter of the body coaxial with the countersink, wherein the grooves are adapted to collapse to allow the end of the countersink to expand in a direction toward the portion of the body between the first and second ends.

In yet another aspect, a wire that may be formed in a torsion spring for use with an axial force generating mechanism includes one or two shaped bends toward an end portion of the wire. In some embodiments, the radius of the shaped bend is between 110% and 190% of the radius of the roller cage in cooperation with the torsion spring in the axial force generating mechanism. In one embodiment, one or both of the shaped bends have a circular arc length defined by an angle between 0 and 90 degrees, or 0 to 60 degrees or 0 to 30 degrees.

These and other inventive embodiments will become apparent to those skilled in the art from the following detailed description, and the corresponding features briefly described below.

Drawings

FIG. 1 is a cross-sectional view of one embodiment of a CVT;

FIG. 2 is a partially exploded cross-sectional view of the CVT of FIG. 1;

FIG. 3 is a cross-sectional view of a second embodiment of a CVT;

FIG. 4 is a partially exploded cross-sectional view of the CVT of FIG. 3;

FIG. 5a is a side view of a keyed input disc drive that may be used in a CVT;

FIG. 5b is a front view of the input disk drive of FIG. 5 a;

FIG. 6a is a side view of a keyed input pad that may be used in the CVT;

FIG. 6b is a front view of the keyed input pad of FIG. 6 a;

FIG. 7 is a cam roller disk that may be used with a CVT;

FIG. 8 is a stator that may be used with a CVT;

FIG. 9 is a perspective view of a flight usable with the CVT;

FIG. 10 is a cross-sectional view of a shift assembly that may be used in the CVT;

fig. 11 is a perspective view of a ball leg assembly for use in the CVT;

FIG. 12 is a perspective view of a cage that can be used in a ball CVT;

FIG. 13 is a cross-sectional view of another embodiment of a CVT;

FIG. 14 is a perspective view of a bicycle hub using an embodiment of the CVT;

FIG. 15 is a top view of various components of the CVT embodiment contained in the bicycle hub of FIG. 14;

figure 16 is a partially exploded perspective view of certain components of the CVT of figure 15;

figure 17 is a top view of certain components of the CVT of figure 15;

FIG. 18 is a cross-sectional view taken along section A-A of the assembly of FIG. 17;

FIG. 19 is a perspective view of one embodiment of a shift cam assembly that can be used with the CVT of FIG. 15;

FIG. 20 is a top view of the shift cam assembly of FIG. 19;

FIG. 21 is a cross-sectional view of section B-B of the shift cam assembly of FIG. 20;

FIG. 22 is a perspective view of a cage assembly that may be used with the CVT of FIG. 15;

FIG. 23 is a front view of the cage assembly of FIG. 22;

FIG. 24 is a right side elevational view of the cage assembly of FIG. 22;

FIG. 25 is a partially exploded front elevational view of the axle-specific vehicle generating component of the CVT of FIG. 15;

FIG. 26 is a cross-sectional view taken along section C-C of the CVT component illustrated in FIG. 25;

FIG. 27 is an exploded perspective view of a cooperating input shaft and twist disk usable with the CVT of FIG. 15;

fig. 28 is a perspective view of the twist disk of fig. 27;

fig. 29 is a left side view of the twist disk of fig. 28;

fig. 30 is a front view of the twist disk of fig. 28;

FIG. 31 is a right side view of the twist disk of FIG. 28;

fig. 32 is a cross-sectional view taken along section D-D of the twist disk of fig. 31;

FIG. 33 is a perspective view of the input shaft of FIG. 27;

FIG. 34 is a left side elevational view of the input shaft of FIG. 33;

FIG. 35 is a top view of the input shaft of FIG. 33;

FIG. 36 is a perspective view of a load cam plate that may be used with the CVT of FIG. 15;

FIG. 37 is a top view of a ball axle assembly that may be used with the CVT of FIG. 15;

FIG. 38 is a cross-sectional view taken along section E-E of the ball axle assembly of FIG. 17;

FIG. 39 is a top plan view of the bicycle hub of FIG. 14;

FIG. 40 is a cross-sectional view taken along section F-F of the hub of FIG. 39, showing certain components of the bicycle hub of FIG. 14 and the CVT of FIG. 15;

FIG. 41 is a perspective view of a spindle that can be used with the CVT of FIG. 15;

FIG. 42 is a top view of the spindle of FIG. 41;

FIG. 43 is a cross-sectional view taken along section G-G of the main axis of FIG. 42;

FIG. 44 is a top view of an alternative embodiment of a CVT usable with the bicycle hub of FIG. 14;

FIG. 45 is a cross-sectional view taken along section H-H of the CVT of FIG. 44;

FIG. 46 is a cross-sectional view of a CVT usable with the bicycle hub of FIG. 14;

FIG. 47 is a cross-sectional view of another embodiment of a Continuously Variable Transmission (CVT);

FIG. 48A is a detail view C of the cross-sectional view shown in FIG. 47, generally illustrating the transducer subassembly;

FIG. 48B is a perspective view of certain components of the CVT shown in FIG. 47, generally illustrating a cage subassembly of the variator subassembly;

FIG. 48C is a perspective cross-sectional view of certain components of the transducer subassembly shown in FIG. 48A;

FIG. 48D is a cross-sectional view of an embodiment of an idler subassembly of the CVT shown in FIG. 47;

FIG. 48E is a perspective exploded view of the idler assembly of FIG. 48D;

FIG. 48F is a cross-sectional view of one embodiment of the idler assembly of FIG. 48D, as used with other components of the CVT shown in FIG. 47;

FIG. 48G is a perspective view of the CVT component illustrated in FIG. 48F;

FIG. 49A is a detail D of the cross-sectional view shown in FIG. 47, generally illustrating the power input device subassembly;

FIG. 49B is a perspective cross-sectional view of the particular CTV component shown in FIG. 49A;

FIG. 49C is a cross-sectional view of certain components of the power input device sub-assembly shown in FIG. 49A;

FIG. 49D is a perspective exploded view of the CVT component shown in FIG. 49C;

FIG. 49E is a perspective exploded view of certain components of the power input device sub-assembly shown in FIG. 49A;

FIG. 50A is a detail view E of the cross-sectional view shown in FIG. 47, generally illustrating the input side axial force generating subassembly;

FIG. 50B is an exploded perspective view of various components of the axial force generation subassembly of FIG. 50A;

FIG. 51 is a detail view F of the cross-sectional view shown in FIG. 47, generally illustrating the output side axial force generation subassembly;

FIG. 52A is a perspective view of a power roller leg subassembly that may be used with the transducer subassembly of FIG. 47;

FIG. 52B is a cross-sectional view of the powered roller leg subassembly illustrated in FIG. 52A;

FIG. 53 is a cross-sectional view of a power roller that may be used with the power roller leg sub-assembly of FIG. 52A;

54A-54C illustrate perspective, cross-sectional, and top views of a power roller shaft that may be used with the power roller leg assembly of FIG. 52A;

FIG. 55 is a cross-sectional view of an alternative embodiment of a power roller shaft;

FIG. 56A is an exploded perspective view of a leg assembly that may be used with the powered roller leg sub-assembly of FIG. 52A;

FIG. 56B is a cross-sectional view of the leg assembly of FIG. 56A;

FIG. 57A is a right perspective view of a stator plate that may be used with the cage subassembly of FIG. 48B;

FIG. 57B is a left perspective view of the stator plate of FIG. 57A;

FIG. 57C is a left plan view of the stator plate of FIG. 57A;

FIG. 57D is a cross-sectional view taken along section line I-I of the stator plate in FIG. 57C;

FIG. 57E is a detail view H of the plan view shown in FIG. 57C, generally illustrating the stator plate biasing slots;

FIG. 58A is a right perspective view of an alternative stator plate;

FIG. 58B is a left perspective view of the stator plate of FIG. 58A;

FIG. 58C is a left plan view of the stator plate of FIG. 58A;

FIG. 58D is a cross-sectional view taken along section line J-J of the stator plate in FIG. 58C;

FIG. 58E is a detail view I of the plan view shown in FIG. 58C, generally illustrating the stator plate biasing slots;

FIG. 59 is a cross-sectional view of a stator bar that may be used with the cage subassembly of FIG. 48B;

60A-60C are perspective, cross-sectional and plan views of a shift rod nut that may be used with the transducer subassembly of FIG. 48A;

61A-61B are perspective and plan views of a shift lever that may be used with the transducer subassembly of FIG. 48A;

FIG. 62A is a perspective view of a traction ring that may be used with the transducer subassembly of FIG. 48A;

FIG. 62B is a left plan view of the traction ring illustrated in FIG. 62A;

FIG. 62C is a front plan view of the traction ring illustrated in FIG. 62A;

FIG. 62D is a cross-sectional view of the traction ring shown in FIG. 62A;

FIG. 62E is a detailed cross-sectional view of the traction ring shown in FIG. 62A;

FIG. 63A is a right plan view of a torsion spring that may be used with the axial force generating subassembly of FIG. 50A or FIG. 51;

FIG. 63B is a front plan view of the torsion spring in a relaxed state;

FIG. 63C is a detail J of the torsion spring of FIG. 63B;

FIG. 63D is a front plan view of the torsion spring in a partially wound condition as it is received in both the traction ring and the roller cage;

FIG. 63E is a detail view K of the torsion spring of FIG. 63D;

FIG. 63F is a front plan view of the torsion spring in a substantially fully wound condition when the torsion spring is received within both the traction ring and the roller cage;

FIG. 64A is a perspective view of a roller cage that may be used with the axial force generating subassembly of FIG. 50A or FIG. 51;

FIG. 64B is a cross-sectional view of the roller cage of FIG. 64A;

FIG. 64C is a plan view of the roller cage of FIG. 64A;

FIG. 64D is a detail view L of a cross-sectional view of the roller cage shown in FIG. 64B;

FIG. 64E is a plan view of a particular state of a force generation and/or preloading subassembly that may be used with the axial force generation subassembly of FIG. 50A or 51;

FIG. 64F is a cross-sectional view along section line K-K of the subassembly shown in FIG. 64E;

FIG. 64G is a plan view of a different state of the axial force generating and/or preloading sub-assembly of FIG. 64E;

FIG. 64H is a cross-sectional view along section line L-L of the subassembly shown in FIG. 64G;

FIG. 65A is a detail view G of the cross-sectional view illustrated in FIG. 47, generally showing a shifter interface subassembly of the CVT;

FIG. 65B is a plan view of a shift lever retainer usable with the shifter interface subassembly of FIG. 65A;

FIG. 65C is a cross-sectional view of the shift lever holder of FIG. 65B;

FIG. 65D is a front plan view of an alternative shift rod retainer nut;

FIG. 65E is a left plan view of the shift rod holder nut of FIG. 65D;

FIG. 65F is a cross-sectional view of the shift rod holder nut of FIG. 65D;

FIG. 65G is a rear plan view of the shift rod holder nut of FIG. 65D;

FIG. 65H is a front plan view of another alternative shift rod retainer nut;

FIG. 65J is a left plan view of the shift rod holder nut of FIG. 65H;

FIG. 65K is a cross-sectional view of the shift rod holder nut of FIG. 65H;

FIG. 66A is a front plan view of a main shaft that may be used with the CVT shown in FIG. 47;

FIG. 66B is a top plan view of the spindle of FIG. 66A;

FIG. 66C is a cross-sectional view taken along section line M-M of the main shaft of FIG. 66B;

FIG. 66D is a detail view M of the spindle shown in FIG. 66A;

FIG. 67A is a perspective view of a power input drive that can be used with the CVT of FIG. 47;

FIG. 67B is a second perspective view of the input driver of FIG. 67A;

FIG. 67C is a rear plan view of the input driver of FIG. 67B;

FIG. 67D is a right plan view of the input driver of FIG. 67B;

FIG. 67E is a cross-sectional view of the input driver of FIG. 67D;

fig. 68A is a perspective view of a twist disk that may be used with the CVT of fig. 47;

fig. 68B is a plan view of the twist disk of fig. 68A;

FIG. 69A is a perspective view of a power input device subassembly including a power input drive and a twist disk;

FIG. 69B is a plan view of the power input device subassembly of FIG. 69A;

FIG. 69C is a cross-sectional view of the power input device subassembly of FIG. 69A;

FIG. 70A is a perspective view of a cam driver that may be used with the CVT of FIG. 47;

FIG. 70B is a plan view of the cam driver of FIG. 70A;

FIG. 70C is a cross-sectional view of the cam driver of FIG. 70B;

FIG. 71A is a perspective view of a flywheel that can be used with the CVT of FIG. 47;

FIG. 71B is a front plan view of the flywheel of FIG. 71A;

FIG. 71C is a top plan view of the flywheel of FIG. 71B;

FIG. 72A is a perspective view of a hub shell that can be used with the CVT of FIG. 47;

FIG. 72B is a cross-sectional view of the hub shell of FIG. 72A;

FIG. 72C is a detail view N of the hub shell of FIG. 72B;

FIG. 72D is a detail view P of the hub shell of FIG. 72B;

FIG. 73 is a perspective view of an alternative hub shell;

FIG. 74 is a perspective view of yet another hub shell;

FIG. 75A is a perspective view of a hub housing cover that can be used with the CVT of FIG. 47;

FIG. 75B is a second perspective view of the hub cover of FIG. 75A;

FIG. 75C is a front plan view of the hub cover of FIG. 75A;

FIG. 75D is a cross-sectional view along section line N-N of the hub housing cover of FIG. 75C;

FIG. 75E is a detail view Q of the cross-sectional view shown in FIG. 75D;

FIG. 75F is a left plan view of the hub housing cover of FIG. 75A;

FIG. 75G is a detail view R of the cross-sectional view shown in FIG. 75F;

FIG. 76A is a perspective view of an alternative hub housing cover that can be used with the CVT of FIG. 47;

FIG. 76B is a front plan view of the hub housing cover of FIG. 76A;

FIG. 76C is a cross-sectional view along section line P-P of the hub housing cover of FIG. 76B;

FIG. 76D is a detail view S of the cross-sectional view shown in FIG. 76C;

FIG. 76E is a left plan view of the hub housing cover of FIG. 76A;

FIG. 76F is a detail view T of the plan view shown in FIG. 76E;

FIG. 77 is a cross-sectional view of one embodiment of an idler and shaft-cam assembly;

FIG. 78 is a cross-sectional view of the idler and shaft cam assembly of FIG. 1 along with a ball leg assembly;

FIG. 79A is a perspective view of an alternative embodiment of an idler and shaft cam assembly;

FIG. 79B is an exploded view of the idler and shaft cam assembly of FIG. 79A;

FIG. 79C is a cross-sectional view of the idler and shaft cam assembly of FIG. 79B;

FIG. 79D is a second cross-sectional view of the idler and shaft cam assembly of FIG. 3B;

FIG. 80A is a perspective view of an alternative embodiment of an idler and shaft cam assembly;

FIG. 80B is an exploded view of the idler and shaft cam assembly of FIG. 80A;

FIG. 80C is a cross-sectional view of the idler and shaft cam assembly of FIG. 80B;

FIG. 80D is a second cross-sectional view of the idler and shaft cam assembly of FIG. 80B;

FIG. 81A is a perspective view of another embodiment of an idler and shaft cam assembly;

FIG. 81B is an exploded view of the idler and shaft cam assembly of FIG. 81A;

FIG. 81C is a cross-sectional view of the idler and shaft cam assembly of FIG. 81B;

FIG. 81D is a second cross-sectional view of the idler and shaft cam assembly of FIG. 81B;

FIG. 82A is a perspective view of yet another embodiment of an idler and axle cam assembly;

FIG. 82B is an exploded view of the idler and shaft cam assembly of FIG. 82A;

FIG. 82C is a cross-sectional view of the idler and shaft cam assembly of FIG. 82B;

FIG. 82D is a second cross-sectional view of the idler and shaft cam assembly of FIG. 82B;

FIG. 83A is a perspective view of a shifter quick release subassembly that can be used with the embodiment of the CVT described above;

FIG. 83B is an exploded perspective view of the quick release subassembly of the shifter of FIG. 83A;

FIG. 83C is a plan view of a backing plate that can be used with the shifter quick release subassembly of FIG. 83A;

FIG. 83D is a cross-sectional view along section line Q-Q of the back plate of FIG. 83C;

FIG. 84A is a cross-sectional view of a shifter interface subassembly that can be used with embodiments of the CVT described above;

FIG. 84B is a plan view of a pulley that can be used with the shifter interface subassembly of FIG. 84A;

FIG. 84C is a cross-sectional view taken along section line R-R of the pulley in FIG. 84B;

FIG. 84D is a plan view of an indexing plate that can be used with the shifter interface subassembly of FIG. 84A;

FIG. 84E is a plan view of a shift lever nut that may be used with the shifter interface subassembly of FIG. 84A;

FIG. 85A is a perspective view of a power input device subassembly that may be used with embodiments of the CVT described above;

FIG. 85B is a plan view of the power input device subassembly of FIG. 85A;

FIG. 85C is a perspective view of a torque transfer key that may be used with the power input device subassembly of FIG. 85A;

FIG. 85D is a plan view of the torque transfer key of FIG. 85C;

FIG. 85E is a perspective view of an input drive that may be used with the power input device subassembly of FIG. 85A;

FIG. 86 is a partial cross-sectional view of another embodiment of a CVT;

FIG. 87 is an exploded partial cross-sectional view of certain components and subassemblies of the CVT of FIG. 86;

FIG. 88 is a cross-sectional view of an idler subassembly of the CVT;

FIG. 89 is a perspective view of a hub shell of the CVT;

FIG. 90 is a cross-sectional view of the hub shell of FIG. 89;

FIG. 91 is a cross-sectional view of another embodiment of a hub shell;

FIG. 92 is an exploded view of a hub shell cover of the CVT;

FIG. 93 is a cross-sectional view of the hub cover of FIG. 92;

FIG. 94 is an elevational view of the hub housing cover of FIG. 92;

FIG. 95 is a cross-sectional view along section line AA-AA of the hub housing cover of FIG. 94;

FIG. 96 is a cross-sectional view along section line BB-BB of the hub housing cover of FIG. 94;

FIG. 97 is a detail view A1 of the hub cover of FIG. 95;

FIG. 98 is a detail view A2 of the hub housing cover of FIG. 94;

FIG. 99 is a second perspective view of the hub cover of FIG. 94;

FIG. 100 is a perspective view of an output drive ring that can be used with the hub cover of FIG. 99;

FIG. 101 is an elevation view of a hub shell and a hub shell cover of the CVT;

FIG. 102 is a perspective view of a locking key that may be used with the hub shell and hub shell cover of FIG. 101;

FIG. 103 is a front view of the locking key of FIG. 102;

FIG. 104 is a cross-sectional view taken along section line CC-CC of the hub shell cover and hub shell of FIG. 101;

FIG. 105 is a perspective view of a CVT with a hub shell cover with a shroud;

FIG. 106 is a perspective view of a CVT having a hub shell cover with a disc brake adapter;

FIG. 107 is a perspective view of a disc brake adapter kit for a CVT;

FIG. 108 is a front elevational view of a disc brake adapter that may be used with the kit of FIG. 107;

FIG. 109 is a rear elevational view of the disc brake adapter of FIG. 108;

FIG. 110 is a cross-sectional view of the disc brake adapter of FIG. 109, as taken along section line DD-DD;

FIG. 111 is a perspective view of a shield that may be used with the kit of FIG. 107;

FIG. 112 is a side view of the shroud of FIG. 111;

FIG. 113 is a cross-sectional view of the shroud of FIG. 111;

FIG. 114 is a perspective view of a shroud that may be used with the hub cover of FIG. 105;

FIG. 115 is a cross-sectional view of the shroud of FIG. 114;

FIG. 116 is a perspective view of an idler bushing that may be used with an idler assembly of a CVT;

FIG. 117 is a front view of the idler bushing of FIG. 116;

FIG. 118 is a cross-sectional view of the idler bushing of FIG. 117;

FIG. 119 is a perspective view of a shift rod nut that may be used with an idler assembly of a CVT;

FIG. 120 is a front elevational view of the shift rod nut of FIG. 119;

fig. 121 is a front view of a shift cam of the CVT;

FIG. 122 is a side elevational view of the shift cam of FIG. 121;

FIG. 123 is a cross-sectional view along section line EE-EE of the shift cam of FIG. 121;

FIG. 124 is a detail view A3 of the shift cam of FIG. 121;

FIG. 125 is a table of values for a shift cam profile for the shift cam of FIG. 121;

FIG. 126 is a perspective view of a traction ring of the CVT;

FIG. 127 is a front view of the ring of FIG. 126;

FIG. 128 is a side view of the ring of FIG. 126;

FIG. 129 is an enlarged detail view A4 of a bevel profile that may be used with the traction ring of FIG. 126;

FIG. 130 is a cross-sectional view of the traction ring of FIG. 126;

FIG. 131 is a view of a non-coiled torsion spring used with the CVT;

fig. 132 is a perspective view of the torsion spring of fig. 131;

fig. 133 is a detail a5 of the torsion spring of fig. 132;

fig. 134 is a detail view a6 of the torsion spring of fig. 132;

FIG. 135 is a perspective view of an input drive for use with the CVT;

FIG. 136 is a side view of the input drive of FIG. 135;

FIG. 137 is a cross-sectional view of the input driver of FIG. 135;

FIG. 138 is a second cross-sectional view of the input driver of FIG. 135;

fig. 139 is a perspective view of a twist disk for use with a CVT;

fig. 140 is a front view of the twist disk of fig. 139;

fig. 141 is a detailed view of the twist disk of fig. 140;

FIG. 142 is a perspective view of an input assembly of the CVT;

FIG. 143 is a cross-sectional view of the input assembly of FIG. 142;

figure 144 is a perspective view of a roller shaft for use with a CVT;

FIG. 145 is a front view of the roller axle of FIG. 144;

FIG. 146 is a cross-sectional view of the roller axle of FIG. 145;

FIG. 147 is a perspective view of a flywheel for use with a CVT;

FIG. 148 is a front view of the flywheel of FIG. 147;

fig. 149 is a plan view of another torsion spring for use with a CVT;

FIG. 150 is a plan view of the torsion spring in the roller cage retainer without the flexure of the torsion spring as in FIG. 149;

fig. 151 is a plan view of the torsion spring of fig. 149 in a roller cage retainer.

Detailed Description

Preferred embodiments are now described with reference to the drawings, wherein like reference numerals refer to like elements throughout. Because the terminology used in the description is used in connection with the detailed description of the specific embodiments of the invention, it is not intended to be interpreted in any limited or restrictive manner. Moreover, embodiments of the invention may include several novel features, no single one of which is solely responsible for its desirable attributes or which is essential to practicing the inventions herein described. CVT embodiments described herein relate generally to those types described in U.S. patent nos. 6241636, 6419608, 6689012, and 7011600. The entire contents of each of these patents are incorporated herein by reference.

As used herein, the terms "operatively connected," "operatively connected," and the like refer to a relationship between elements (mechanical, coupled, etc.) whereby operation of one element results in the corresponding, subsequent, or simultaneous operation or actuation of a second element. It is noted that in describing embodiments of the invention using the terms, the specific structure or mechanism of the connecting or coupling elements is generally described. However, unless otherwise specifically stated, when only one of the terms is used, it is intended that the actual connection or coupling may take a variety of forms, as will be apparent to those of ordinary skill in the art in certain instances.

For purposes of this description, the term "radial" is used herein to refer to a direction or position perpendicular to the longitudinal axis of the transmission or variator. The term "axial" as used herein refers to a direction or position along an axis parallel to the main or longitudinal axis of the transmission or variator. For clarity and simplicity, sometimes similarly labeled components (e.g., control piston 582A and control piston 582B) will be collectively referred to by one label (e.g., control piston 582).

Referring now to fig. 1, a ball type CVT100 is shown that can change input-to-output gear ratios. The CVT100 has a central shaft 105, the central shaft 105 extending through the center of the CVT100 and beyond the two dropout ends 10 of the bicycle frame. A first cap nut 106 and a second cap nut 107, each located at a respective end of the central shaft 105, connect the central shaft 105 to the rear fork ends. While this embodiment illustrates the CVT100 being used on a bicycle, the CVT100 can be used on any device that utilizes a transmission. For purposes of illustration, the central shaft 105 defines a longitudinal axis of the CVT that will serve as a reference point for describing the position and/or movement of other components of the CVT. As used herein, the terms "axial," "axially," "lateral," "laterally" refer to a position or direction that is coaxial or parallel to the longitudinal axis defined by the central shaft 105. The terms "radial" and "radially" refer to a position or direction extending perpendicularly from the longitudinal axis.

Referring to fig. 1 and 2, central shaft 105 provides radial and lateral support for cage assembly 180, input assembly 155, and output assembly 160. In this embodiment, the central shaft 105 includes a bore 199 that receives the shift rod 112. As described later, the shift lever 112 performs gear ratio change in the CVT 100.

The CVT100 includes a variator 140. The variator 140 can be any mechanism suitable for varying the ratio of input speed to output speed. In one embodiment, variator 140 includes input disc 10, output disc 134, tiltable ball leg assembly 150, and idler assembly 125. The input disc 110 may be a disc that is rotatable about the central axis 105 and mounted coaxially therewith. At the radially outer edge of the input disc 110, the disc extends at an angle to the point where it terminates at the contact surface 111. In some embodiments, the contact surface 111 may be a separate structure, such as a ring, that is attached to the input disc 110, and the input disc 110 will provide support to the contact surface 111. The contact surface 111 may be threaded or press fit into the input disc 110, or it may be attached by any suitable fastener or adhesive.

The output disc 134 may be a ring press-fit or otherwise connected to the output hub shell 138. In certain embodiments, the input and output discs 110, 134 have support structures 113 extending radially from the contact surface 111 that provide structural support that increases radial stiffness to resist deformation of those portions under axial forces of the CVT100 and allow the axial force mechanisms to move radially outward, thereby reducing the length of the CVT 100. The input and output discs 110, 134 may have oil holes 136, 135 that allow lubricating oil to enter the variator 140 to circulate through the CVT 100.

In certain embodiments, the hub shell 138 is a cylindrical tube that is rotatable about the central axis 105. The hub shell 138 has an interior portion that houses the major components of the CVT100 and an exterior portion that is adapted to connect to whatever component, equipment or vehicle the CVT is used for. Here, the exterior of the hub shell 138 is configured to be used on a bicycle. However, the CVT100 may be used in any machine where it is desirable to regulate the input and output speeds of rotation.

Referring to fig. 1, 2, 10 and 11, the CVT may include a ball-leg assembly 150 for transmitting torque from the input disc 110 to the output disc 134 and varying the ratio of input speed to output speed. In some embodiments, ball-and-leg assembly 150 includes a ball 101, a ball axle 102, and a leg 103. The shaft 102 may be a generally cylindrical shaft that extends through a hole formed in the center of the ball 101. In some embodiments, shaft 102 contacts the surface of the bore in ball 101 through a needle bearing or radial bearing aligned with ball 101 on shaft 102. The shaft 102 extends beyond the side of the ball 101 where the hole is located so that the leg 103 can perform a shift in the position of the ball 101. Where the shaft 102 extends beyond the edge of the ball 101, it is connected to the radially outer ends of the legs 103. The legs 103 are radial extensions that tilt the ball axles 102.

The shaft 102 passes through holes formed at the radially outer ends of the legs 103. In some embodiments, leg 103 has a cavity in which shaft 102 passes through the bore of leg 103, reducing stress concentrations in contact between leg 103 and shaft 102. This small head stress improves the ability of the ball leg assembly 150 to absorb shifting forces and torque reactions. The legs 103 may be positioned on the shaft 102 by a locking ring (e.g., an E-ring) or press fit on the shaft 102; however, any other means of securing between the shaft 102 and the leg 103 may be used. The ball-and-leg assembly 150 may also include rolling element leg rollers 151 connected to each end of the ball axle 102, the leg rollers 151 providing rolling contact of the axle 102 when the axle 102 is aligned with other portions of the CVT 100. In some embodiments, the legs 103 have cams 152 at the radially inner ends to facilitate control of the radial position of the legs 103, and thus the angle of inclination of the shaft 102. In other embodiments, the leg 103 is connected to a cam 1105 (see fig. 11) to allow the leg 103 to be guided and supported in the stator 800 (see fig. 8). As shown in fig. 1, the stator wheel 1105 may be inclined relative to the longitudinal axis of the leg 103. In some embodiments, the stator wheel 1105 is configured such that its central axis intersects the center of the ball 101.

Still referring to fig. 1, 2, 10, and 11, in various embodiments, the contact between the ball 101 and the shaft 102 may be any of the bearings described in other embodiments below. However, in other embodiments, the ball 101 is fixed to a shaft for rotation with the ball 101. In some such embodiments, bearings (not shown) are located between the shaft 102 and the legs 103, such that lateral forces acting on the shaft 102 are reacted by the legs 103, or alternatively, also by the cage (described in embodiments below). In some such embodiments, the bearings between the shaft 102 and the legs 103 are radial bearings (ball or needle bearings), journal bearings, or any other type of bearing, or suitable mechanism or device.

Referring to fig. 1, 2, 3, 4, and 10, the idler assembly 125 will now be described. In certain embodiments, the idler assembly 125 includes an idler 126, a cam plate 127, and an idler bearing 129. Idler pulley 126 has a substantially constant outer diameter; however, in other embodiments, the outer diameter is not constant. The outer diameter may be smaller in the middle portion than in the end portions, or larger in the middle portion and smaller in the end portions. In other embodiments, the outer diameter is larger at one end than at the other, and the change between the two ends may be linear or non-linear depending on shift speed and torque requirements.

Cam plates 127 are located at either or both ends of idler 126 and contact cams 152 to actuate legs 103. In the illustrated embodiment, the cam plate 127 is convex, but may be any shape that produces the desired movement of the legs 103. In certain embodiments, the cam plate 127 is configured such that its axial position controls the radial position of the legs 103, and thus the angle of inclination of the shaft 102.

In certain embodiments, the radial inner diameters of the cam plates 127 extend axially from one another to connect one cam plate 127 to another cam plate 127. Here, the cam extension 128 forms a cylinder around the central shaft 105. The cam extension 128 extends from one cam plate 127 to the other cam plate 127 and is secured in place by a locking ring, nut, or some other suitable fastener. In some embodiments, one or both cam plates 127 are threaded onto the cam plate extension 128 to secure it in place. In the illustrated embodiment, the convex curve of the cam plate 127 extends axially from the axial center of the idler assembly 125 to a local maximum, then radially outward, and then axially inward back toward the axial center of the idler assembly 125. Such a cam profile reduces binding that may occur at the axial extremes during shifting of the idler assembly 125. Other cam shapes may also be used.

In the embodiment of fig. 1, a shift lever 112 performs gear ratio shifting of the CVT 100. The shift rod 112, which is coaxially positioned within the bore 199 of the central shaft 105, is an elongated rod having a threaded end 109, the threaded end 109 extending out one side of the central shaft 105 and beyond the cap nut 107. The other end of the shift lever 112 extends into the idler assembly 125 where a shift pin 114 is contained, the shift pin 114 being generally transversely mounted within the shift lever 112. The shift pin 114 engages the idler assembly 125 such that the shift lever 112 may control the axial position of the idler assembly 125. The lead screw assembly 115 controls the position of the shift lever 112 within the central shaft 105. In certain embodiments, lead screw assembly 115 includes a shift actuator 117, which shift actuator 117 may be a pulley having a set of cable threads 118 on an outer diameter and threads on a portion of an inner diameter thereof engaging shift rod 112. The lead screw assembly 115 may be held in place axially on the central shaft 105 by any means, here by a pulley snap ring 116. The tether threads 118 engage a shift cable (not shown). In some embodiments, the shift cable is a standard shift wire, while in other embodiments, the shift cable can be any cable that can be placed under tension to rotate shift pulley 117.

Referring to fig. 1 and 2, an input assembly 155 allows torque to be input to the variator 140. The input assembly 155 has a sprocket 156 that converts linear motion of a chain (not shown) into rotational motion. Although sprockets are used here, other embodiments of the CVT100 may use pulleys that receive motion from, for example, a conveyor belt. The sprocket 156 transmits torque to an axial force generating mechanism, which in the illustrated embodiment is a cam loader 154 that transmits torque to the input disc 110. Cam loader 154 includes a cam plate 157, a load plate 158, and a set of cam rollers 159. The cam loader 154 transfers torque from the sprocket 156 to the input disc 110 and generates an axial force that overcomes the contact forces of the input disc 110, the balls 101, the idler 126, and the input disc 134. The axial force is generally proportional to the amount of torque applied to the cam loader 154. In some embodiments, the sprocket 156 applies torque to the cam plate 157 through a one-way clutch (not shown in detail) that acts as an idler mechanism when the hub 138 is rotating and the sprocket 156 is not providing torque. In some embodiments, load disk 158 may be integrated with input disk 157 as a single piece. In other embodiments, the cam loader 154 is integral with the output disc 134.

In fig. 1 and 2, the inner components of the CVT100 are contained within the hub shell 138 by an end cover 160. The end cap 160 is a generally planar disk attached to the open end of the hub shell 138 with an aperture through the center to allow passage of the cam plate 157, the central shaft 105 and the shift rod 112. An end cap 160 is coupled to the hub shell 138 for reacting the axial force generated by the cam loader 154. End cap 160 may be made of any material capable of reacting axial forces, such as aluminum, titanium, steel, or a rigid thermoplastic or thermoset. The end cap 160 is secured to the hub shell 138 by fasteners (not shown); however, the end cap 160 can also be threaded or otherwise attached to the hub shell 138. The end cap 160 has a groove formed around a radius on a side thereof facing the cam loader 154 that receives a preloader 161. Preloader 161 may be any device capable of applying an initial force to cam loader 154 and thus to input disc 134, such as a spring, or a resilient material such as an O-ring. Preloader 161 may be a wave spring, so that the spring may have a high spring constant and a high level of resiliency over its entire life. Here, the preloader 161 is loaded directly onto the end cover 160 through the thrust washer 162 and the thrust bearing 163. In this case, thrust washer 162 is typically an annular washer that covers the groove of preloader 161 and provides a thrust race for thrust bearing 163. The thrust bearing 163 may be a needle thrust bearing with high level thrust capability, improving structural rigidity and reducing tolerance requirements and cost compared to a combination thrust radial bearing; however, any form of thrust bearing or combination bearing may be used. In some embodiments, the thrust bearing 163 is a ball thrust bearing. The axial force generated by the cam loader 154 is reacted through the thrust bearing 163 and the thrust washer 162 to the end cap 160. An end cap 160 is connected to the hub shell 138 to complete the structure of the CVT 100.

In fig. 1 and 2, the cam plate bearing 172 holds the cam plate 157 in a radial position relative to the central axis 105, while the end cap bearing 173 holds the cam plate 157 in radial alignment with the inner diameter of the end cap 160. Here, the cam disc bearing 172 and the end cap bearing 173 are needle roller bearings; however, other forms of radial bearings may be used. The use of needle bearings allows for increased axial float and accommodates the binding moments generated by the rider and the sprocket 156. Either or both of the cam plate bearing 172 and the end cap bearing 173 may also be replaced by mating combination radial thrust bearings in other embodiments of the CVT100 or any other embodiment described herein. In such an embodiment, the radial thrust bearing not only provides radial support, but also absorbs thrust forces, helping to at least partially aid in load shedding of the thrust bearing 163.

Still referring to fig. 1 and 2, the shaft 142 is a support member that is coaxially mounted about the central axis 102 and that is retained between the central axis 102 and the inner diameter of the closed end of the hub shell 138, the shaft 142 maintaining the hub shell 138 in radial alignment relative to the central axis 105. The shaft 142 is fixed in angular alignment with the central axis 105. Here, key 144 fixes the angular alignment of shaft 142, but the fixing may be by any means known to those skilled in the art. A radial hub bearing 145 is mounted between the shaft 142 and the inner diameter of the hub shell 138 to maintain the radial position and axial alignment of the hub shell 138. The hub bearing 145 is held in place by a sealing shaft cover 143. The axle cap 143 is a disk having a central bore that fits around the central axle 105 and is connected to the hub shell 138 here by fasteners 147. The hub thrust bearing 146 is mounted between the hub shell 138 and the retainer 189 to maintain the axial position of the retainer 189 and the hub shaft 138.

Fig. 3, 4 and 10 show an alternative embodiment CVT 300 of the CVT100 described above. Many of the components between the above-described CVT100 embodiment and the present figure are similar. Here, the angles of the input disc 310 and the output disc 334 are respectively reduced to allow greater strength against axial force and reduce the overall radial diameter of the CVT 300. This embodiment shows an alternative shift mechanism in which a lead screw mechanism is formed on the shift lever 312 to perform axial movement of the idler assembly 325. The lead screw assembly is a set of lead threads formed on one end of the swap bar 312 in or near the idler assembly 325. One or more idler assembly pins 314 extend radially from the cam plate extension 328 into the lead screw 313, which move axially as the shift rod 312 rotates.

In the illustrated embodiment, the idler 326 does not have a constant outer diameter, but rather has an outer diameter that is enlarged at one end of the idler 326. This allows the idler 326 to resist forces on the idler 326 that may be generated by dynamic contact forces and rotational contact attempting to push the idler 326 away from a center position. However, this is merely an example, and the outer diameter of the idler 326 may be varied in any manner desired by the designer to react rotational forces experienced by the idler 326 and facilitate shifting of the CVT 300.

Referring now to fig. 5a, 5b, 6a and 6b, the two-part disk is comprised of a splined disk 600 and a disk drive 500. The disk drive 500 and the splined disk 600 are mounted together by means of splines 510 formed on the disk drive 500 and splined holes 610 formed in the splined disk 600. The splines 510 are mounted within the splined bore 610 such that the disk driver 500 and the splined disk 600 form a disk for use in the CVT100, CVT 300, or any other ball-type CVT. The splined disc 600 provides flexibility in the system to allow the variator 140, 340 to find a balanced position, reducing sensitivity to component machining tolerances of the variator 140, 340.

Fig. 7 illustrates a cam plate 700 that can be used in the CVT100, CVT 300, other ball-type CVTs, or any other type of CVT. The cam plate 700 has a cam channel 710 formed in its radially outer edge. The cam channel 710 houses a set of cam rollers (not shown), which in this embodiment are spheres (e.g., bearing balls), but may be any shape that cooperates with the cam channel 710, to convert torque into a torque component and an axial force component to moderate the axial force applied to the variator 140, 340 in a manner proportional to the torque applied to the CVT. Other such shapes include cylindrical rollers, barrel rollers, asymmetric rollers, or any other shape. In many embodiments, the material used for the cam plate channel 710 is preferably sufficiently stiff to resist excessive or permanent deformation under the loads to which the cam plate 700 will be subjected. In high torque applications, special hardening treatments may be required. In certain embodiments, the cam plate channel 710 is made of carbon steel hardened to a rockwell hardness value in excess of 40 HRC. The operating efficiency of the cam loader (154 of fig. 1, or any other form of cam loader) may be affected by hard values, typically by increasing the hardness to increase efficiency; however, high hardness can result in the cam loading member becoming brittle and leading to higher costs. In certain embodiments, the hardness exceeds 50HRC, while in other embodiments, the hardness exceeds 55HRC, exceeds 60HRC, and exceeds 65 HRC.

Fig. 7 illustrates an embodiment of a conformal cam. That is, the shape of the cam channel 710 conforms to the shape of the cam roller. Since the channels 710 are in line with the rollers, the channels 710 act as bearing roller retainers, eliminating the need for cage elements. The embodiment of fig. 7 is a one-way cam plate 700; however, the cam plate may be a bidirectional cam as in CVT 1300 (see fig. 13). Eliminating the need for bearing roller retainers simplifies the design of the CVT. The conformal cam channels 710 also allow for reduced contact stresses between the bearing rollers and the channels 710, allow for reduced size and/or number of bearing rollers, or allow for greater flexibility in material selection.

Fig. 8 shows a cage plate 800 for forming a rigid support structure for the cages 189 of the variators 140, 340 in ball-type CVTs 100, 300 (and other types). The cage plate 800 is shaped to guide the legs 103 as the legs 103 move radially inward and outward during shifting. The cage plate 103 also provides angular alignment of the shaft 102. In some embodiments, the corresponding slots of the two cage discs 800 of each shaft 102 are slightly angularly offset to reduce the shifting forces in the shifters 140 and 340.

The legs 103 are guided by slots in the stator. The leg rollers 151 on the legs 103 follow a circular profile in the stator. The leg rollers 151 generally provide a translational reaction point that counters the smoothing force caused by shifting forces or traction contact rotational forces. When the CVT transmission ratio is changed, the legs 103 and their respective leg rollers 151 move in a plane so as to trace a circular orbit centered around the ball 101. Since the legs 151 are offset from the center of the legs 103, the leg rollers 151 trace out a similarly offset footprint. To produce a consistent profile on each stator to match the planar motion of the leg rollers 151 requires a circular cut-out offset from the slot center by the same amount as the rollers are offset in each leg 103. The circular incision can be made using a rotary cutter; however, it requires a separate cut at each slot. Since each cut is independent, there is the possibility of tolerance variations from one slot to the next in a single stator, in addition to variations between stators. A way to eliminate this extra machining step is to provide a profile that can be produced by a turning operation of the lathe. The circular machine cut can produce this single profile in one rotation operation. The center of the ring cut is adjusted away from the center of the ball 101 in the radial direction to compensate for the offset of the leg rollers 103.

Referring now to fig. 1, 9 and 12, an alternative embodiment of the cage assembly 1200 is shown using lubrication enhancing lubrication shims 900 for use with certain CVTs, where the shims 1210 support and isolate two cage discs 1220. In the illustrated embodiment, in this case where a cage 389 is employed, the support structure for the power transmission element is formed by connecting the input and output side cage discs 1220 to a plurality of shims 1210 (including one or more lubrication shims 900 with cage fasteners 1230). In this embodiment, the cage fasteners 1230 are screws, but they may be any form of fastener or fastening method. The lubricating washer 900 has a wiper 910 for scraping lubricating oil from the surface of the hub shell 138 and directing the lubricating oil back to the center element of the transducer 140 or 340. Some embodiments of lubrication pad 900 also have channels 920 that help the lubrication flow to the areas where the lubrication is most used. In some embodiments, the portion of the gasket 900 between the channels 920 forms a raised wedge 925 that directs the grease to the channels 920. The wiper 910 may be integral with the gasket 900 or may be separate and made of a different material (including but not limited to rubber) than the wiper 910 to increase the scraping of the grease from the hub shell 138. The ends of the shims 1210 and 900 are at a flange-like base 1240, the base 1240 extending vertically to form a surface for cooperating with the cage plate 1220. The base 1240 of the illustrated embodiment is generally planar on the side facing the cage disc 1240, but is rounded on the side facing the ball 101 to form the surface on which the leg rollers 151 roll as described above. The base 1240 also forms a channel within which the legs 103 roll throughout their travel.

Embodiments of lubrication systems and methods are now described with reference to fig. 3, 9, and 10. As the ball 101 rotates, the lubricant tries to flow toward the equator of the ball 101, and then the lubricant is sprayed on the hub shell 138. Some of the lubricating oil does not land on the inner wall of the hub shell 138 having the largest diameter; however, the centripetal force causes the lubrication to flow to the largest inner diameter of the hub shell 138. The wiper 910 is vertically positioned so that it removes grease that accumulates on the inside of the hub shell 138. Gravity pulls the oil down on each side of the V-shaped flange into the channel 920. The spacer 900 is positioned such that the radially inner end of the channel 920 terminates adjacent the cam plate 127 and idler 126. As such, the idler pulley 126 and the cam plate 127 receive lubrication oil circulating within the hub shell 138. In one embodiment, the blades 910 are sized to scrape about thirty thousandths of an inch across the hub shell. Of course, the gap may be larger or smaller depending on the application.

As shown in fig. 3 and 10, the cam plate 127 may be configured such that the side thereof facing the idler 226 is sloped to receive lubricating oil falling from the channel 920 and direct the lubricating oil to the space between the cam plate 127 and the idler 226. After the flow of lubricant on the idler 226, the lubricant flows to the largest diameter of the idler 226 where some of the lubricant is sprayed on the shaft 102. Some of the oil falls from passage 920 onto idler 226. This oil lubricates the idler 226 and the contact path between the balls 101 and the idler 226. Due to the inclination of each side of the idler 226, some of the lubricant flows centrifugally outwardly toward the edge of the idler 226 and then sprays radially outwardly therefrom.

Referring to fig. 1, 3 and 10, in some embodiments, the spray of oil from the idler 126, 226 toward the shaft 102 lands on a groove 345, which groove 345 receives the oil and pumps it into the ball 101. Some of the oil also lands on the contact surfaces 111 where the input disc 110 and the output disc 134 contact the balls 101. When the lubricant oil leaves one side of the ball 101, the lubricant oil flows toward the equator of the ball 101 by centrifugal force. A part of this lubricating oil contacts the contact surface 111 of the input disc 110 with the ball 101 and then flows toward the equator of the ball 101. A portion of the lubricant flows radially outward along the side of the output disc 134 facing away from the balls 101. In some embodiments, the input disc 110 and/or the output disc 134 are provided with lubrication holes 136 and 135, respectively. The grease holes 135, 136 direct grease to the largest inside diameter of the hub shell 138.

Fig. 13 shows an embodiment of a CVT 1300 having two cam loaders 1354 that collectively generate and distribute the axial force of the CVT 1300. Here, the cam loader 1354 is located near the input disc 1310 and the output disc 1334. The CVT 1300 illustrates how torque is provided through the input disc 1310 and output through the output disc 1334, or vice versa, such that torque is input through the output disc 1334 and output through the input disc 1310.

Fig. 4 illustrates a bicycle hub 1400 configured to incorporate the inventive features of the CVT embodiments described above. Several of the components of the hub 1400 are identical to those described above; therefore, further description of these components is defined. The hub 1400 includes a hub shell 138 connected to a hub cap 1460. In certain embodiments, the hub 1400 further includes an end cap 1410 sealing an end of the hub shell 138 opposite the hub cap 1460. The hub shell 138, the hub cap 1460, and the end cap 1410 are preferably made of materials that provide structural strength and rigidity. Such materials include, for example, steel, aluminum, magnesium, high strength plastics, and the like. In certain embodiments, other materials may also be suitable, depending on the specific requirements of a given technical application. For example, the hub shell 138 can be made of a composite material, a thermoplastic, a thermoset, or the like.

Referring now to fig. 14, a hub 1400 is shown housed within the CVT embodiments described herein. The main axle 105 supports the hub 1400 and provides a connection to the rear fork end 10 of a bicycle or other vehicle or device. The spindle 105 of this embodiment is described in further detail with reference to fig. 41-43. In some embodiments, as shown in fig. 15-18, CVT1500 includes a shifter having a rod 112 with a threaded end 109. Nuts 106 and 107 lock the dropout 10 to the main shaft 105. In the embodiment of fig. 14, hub 1400 includes a flywheel 1420, flywheel 1420 operably connected to an input shaft (see fig. 33 and 40) to input torque to CVT 1500. It should be noted that while various embodiments and features of the CVT have been described with reference to a bicycle application, readily appreciated variations of the CVT and its features can be used in vehicles, machines or devices that use a transmission.

Referring to fig. 15 and 16, in one embodiment, CVT1500 has an input disc 1545 for transmitting torque to a spherical traction roller (here shown as balls 101). Fig. 16 is a partially exploded view of the CVT 1500. The balls 101 transmit torque to the output disc 1560. In this embodiment, only one ball 101 is shown to clearly illustrate the various cycles of the CVT1500, however, various embodiments of the CVT use 2 to 16 or more balls 101 wherever possible, depending on the torque, weight and size requirements of each particular application. Different embodiments use 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 or more balls 101. An idler 1526 mounted coaxially around the main shaft 105 contacts and provides support for the balls 101, maintaining their radial position around the main shaft 105. The input disc 1545 of some embodiments has lubrication ports 1590 that facilitate circulation of lubrication oil through the CVT 1500.

Referring additionally to fig. 37-38, the ball 101 rotates on an axle 3702. The legs 103 and shift cams 1527 act together as levers to vary the position of the shaft 3702, which shifts result in the tilting of the balls 101 to effect the above-described change in transmission ratio. The cage 1589 (see fig. 22-24) provides for and aligns the legs 103 as the shift cams 1527 actuate the radial movement of the legs 103. In one embodiment, the cage includes stators 1586 and 1587 connected by stator spacers 1555. In other embodiments, other cages 180, 389, 1200 are used.

Referring additionally to fig. 41-43, in the illustrated embodiment, a cage 1589 is mounted coaxially, non-rotatably, about the main shaft 105. In this embodiment, the stator 1586 is rigidly attached to the flange 4206 of the main shaft 105. Additional flanges 1610 hold the stator 1587 in place. Key 1606 connects flange 1610 to spindle 105, and spindle 105 has a key receptacle 1608 for receiving key 1606. Of course, those of ordinary skill in the art will readily recognize that there are many equivalent and alternative ways to attach the main shaft 105 to the flange 1610, or to attach the stators 1586, 1587 to the flanges 1620, 4206. In certain embodiments, the main shaft 105 includes a shoulder 4310 for axially locating and constraining the flange 1610.

The end cap 1410 is mounted on a radial bearing 1575, which bearing 1575 is itself mounted on the flange 1610. In one embodiment, the radial bearing 1575 is an angular contact bearing that supports ground reaction loads and radially aligns the hub shell 138 with the main shaft 105. In certain embodiments, the hub 1400 includes a seal at one or both ends of the main shaft 105. For example, here, the hub 1400 has a seal 1580 at the end where the hub shell 138 and the end cap 1410 are joined together. Additionally, to provide an axial force preload on the output side and maintain the axial position of the hub shell 138, the hub 1400 may include spacers 1570 and needle thrust bearings (not shown) between the stator 1587 and the radial bearing 1575. A spacer 1570 is coaxially mounted about the flange 1610. In some embodiments, needle thrust bearings may not be used, in which case the radial bearing 1575 may be an angular contact bearing adapted to carry thrust loads. One of ordinary skill in the art will readily recognize alternative means of performing the radial thrust load function that may be provided by providing the spacer 1570, needle thrust bearing and radial bearing.

Still referring to fig. 143, 15 and 16, in the illustrated embodiment, the variator 1500 of the hub 1400 includes an input shaft 1505, one end of the input shaft 1505 being operatively connected to the twist plate 1525. The other end of the input shaft 1505 is operatively connected to the flywheel 1420 through the flywheel bracket 1510. The torsion disc 1525 is configured to transmit torque to a load cam disc 1530 (see fig. 36) having ramps 3610. Load cam plate 1530 transmits torque and axial force to a set of rollers 2504 (see fig. 25), which rollers 2504 in turn act on second load cam plate 1540. Input disc 1545 is coupled to second load cam disc 1540 to receive torque and axial force inputs. In some embodiments, the rollers 2504 are held in place by a roller cage 1535.

As is well known, many traction CVTs utilize a clamping mechanism to prevent slippage between the balls 101 and the input disc 1545 and/or the output disc 1560 when transmitting a certain level of torque. Providing a clamping mechanism is sometimes referred to herein as generating an axial force, or providing an axial force generator. The above-described structure of the load cam plate 1530 that cooperates with the load cam 1540 through the rollers 2504 is one such axial force generating mechanism. However, in some embodiments, when the axial force generating device-type subassembly generates an axial force in the CVT, a reaction force is also generated in the CVT itself. With additional reference to fig. 25 and 26, in the embodiment of the CVT1500 shown, the reaction force is reacted at least in part by thrust bearings having first and second races 1602, 1603, respectively. In the illustrated embodiment, the bearing elements are not shown, but may be balls, rollers, barrel rollers, asymmetric rollers, or any other form of rollers. Additionally, in certain embodiments, one or both races 1602 are made of various bearing race materials, such as steel, bearing steel, ceramic, or any other material for bearing races. The first race 1602 is against the twist plate 1525 and the second race 1603 is against the hub cover 1460. The hubcap 1460 of the illustrated embodiment absorbs reaction forces generated by the axial force mechanism. In certain embodiments, axial force generation includes additionally providing a preloader, such as one or more axial springs, for example, a wave spring 1515 or a torsion spring 2505 (see description of fig. 25 below).

Referring to fig. 15-18, 22-24 and 43, some subassemblies of a CVT1500 are shown. The stator 1586 is mounted on a shoulder 4208 of the main shaft 105 and abuts against a flange 4206 of the main shaft 105. The stator 1587 is mounted on a shoulder 1810 of the flange 1610. Here, screws (not shown) attach the flange 4206 to the stator 1586 and the flange 1610 to the stator 1587, however, in other embodiments, the stator 1587 is threaded onto the shoulder 1810, but the stator 1587 can be attached to the shoulder 1810 by any method or means. In this embodiment, because the flanges 1610 and 4206 are non-rotatably fixed to the main shaft 105, the cage 1589 formed by the stators 1586 and 1587 therein is non-rotatably attached to the main shaft 105. The stator spacers 1555 provide additional structural strength and rigidity to the cage 1589. In addition, the stator spacers 1555 facilitate precise axial spacing between the stators 1586 and 1587. The stators 1586 and 1587 guide and support the legs 103 and the shaft 3702 through the guide grooves 2202.

Referring now to fig. 15-21, 37, 38, the ball 101 rotates about the axle 3702 and contacts the idler 1526. Bearings 1829 mounted coaxially about the main shaft 105 support the idler 1526 in its radial position, wherein the bearings 1829 may be separate from or integral with the idler 1526. The shift pin 114, controlled by the shift rod 112, actuates axial movement of the shift cam 1527. The shift cams 1527 then actuate the legs 103, functionally resulting in the application of a lever or pivoting action on the axle 3702 of the ball 101. In some embodiments, the CVT1500 includes a retainer 1804 that holds the shift pin 11 against the Hover idler 1526. The retainer 1804 can be a ring made of plastic, metal, or other suitable material. The retainer 1804 is mounted between bearings 1829 and coaxially around the shift cam extension 1528.

Fig. 19-21 illustrate one embodiment of the shift cams 1527 of the CVT1500 shown. Each shift cam disc 1572 has a profile 2110 along which the legs 103 run. Here, the profile 2110 generally has a convex shape. Generally, the shape of the profile 2110 is determined by the desired leg 103 movement, which ultimately affects the shifting performance of the CVT 150. The shift cam profile is described further below. As shown, one of the shift cam plates 1527 has an extension 1528 mounted around the main shaft 105. The extension 1528 of the illustrated embodiment is long enough to extend beyond the idler 1526 and connect to another shift cam plate 1527. Here, the connection is provided by a sliding fit and a clamp. However, in other embodiments, the shift cams 1527 may be secured to each other by threads, screws, interference fit, or any other method of attachment. In some embodiments, an extension 1528 is provided as an extension from each shift cam 1527. The shift pin 114 is mounted in a hole 1910 through the extension 1528. In some embodiments, the shift cam 1527 has an aperture 1920 that facilitates the flow of lubrication oil through the idler bearing 1829. In certain embodiments, the idler bearing 1829 is press fit into the extension 1528. In some embodiments, the aperture 1920 facilitates removal of the idler bearing 1829 from the extension 1528 by allowing a tool to pass through the shift cam 1527, pushing the idler bearing 1829 away from the extension 1528. In certain embodiments, idler bearings 1829 are angular contact bearings, while in other embodiments they are radial bearings or thrust bearings or any other type of bearing. Many materials are suitable for making such a shift cam 1527. For example, some embodiments use materials such as steel, aluminum, or magnesium, while other embodiments use other materials such as composites, plastics, or ceramics, depending on the circumstances of each particular application.

The illustrated shift cam 1527 is one embodiment of a shift cam profile 2110 having a generally convex shape. The shift cam profile generally varies depending on the location of the point of contact between the idler 1526 and the ball-leg assembly 1670 (see fig. 16) and the amount of relative axial movement between the ball 101 and the idler 1526.

Referring now to fig. 16 and 18-21, the profile of the shift cam 1527 is such that the axial translation of the idler 1526 relative to the ball 101 is proportional to the angular change of the axis of the ball 101. Here, the angle of the axis of the ball 101 is referred to as "γ". Applicants have discovered that controlling the axial displacement of the idler 1526 relative to the change in γ affects the CVT ratio control force. For example, in the illustrated CVT1500, if the axial translation of the idler 1526 is linearly proportional to the gamma change, then the positive direction of the shift cam 1527 and ball-leg interface is generally parallel to the shaft 3702. This enables efficient conversion of the horizontal shifting force into a shifting moment about the ball-leg assembly 1670.

The linear relationship between idler translation and γ is given as the idler translation being the product of the radius of the ball 101, the γ angle, and RSF (i.e., idler translation ═ ball radius × γ angle × RSF), where RSF is the rolling slip factor. RSF describes the lateral creep rate between the ball 101 and the idler 126. As used herein, "creep" is the discontinuous local movement of a body relative to another body. In a traction device, the transmission of power from a driving element to a driven element through a traction interface requires creep. In general, creep in the power transmission direction is referred to as "creep in the rolling direction". Sometimes the driving element and the driven element experience creep in a direction perpendicular to the direction of power transmission, in which case this component of creep is referred to as "lateral creep". During operation of the CVT, the balls 101 and the idler 1526 roll on each other. As the idler 126 translates axially (i.e., perpendicular to the rolling direction), lateral creep occurs between the idler 1526 and the balls 101. An RSF equal to 1.0 represents pure scrolling. At RSF values less than 1.0, the idler 1526 translates slower than the ball 101 rotates. At RSF values greater than 1.0, the idler 1526 translates faster than the ball 101 rotates.

Still referring to the embodiment shown in fig. 16, applicants have devised a process to plan all variations in cam profiles of lateral creep and/or contact position between the idler 1526 and the ball leg assembly 1579. This process creates different cam profiles that help determine the effects of shift force and shifter displacement. In one embodiment, the process includes determining a two-dimensional data curve having a desired cam profile using a parametric formula. This curve is then used to generate a model of the shift cam 127. In one embodiment of the process, the data is typically formulated as follows:

θ＝2＊γ_MAX＊t-γ_MAX

x＝LEG＊sin(θ)-0.5＊BALL_DIA＊RSF＊θ＊pi/180+0.5＊ARM＊cos(θ)

y＝LEG＊cos(θ)-0.5＊ARM＊sin(θ)

z＝0

the angle theta varies from a minimum gamma (in some embodiments-20 degrees) to a maximum gamma (in some embodiments +20 degrees). γ _ MAX is the maximum γ. The parameter range variable "t" varies from 0 to 1. Here, "x" and "y" are the center points of the cam 152 (see fig. 1). The formula for x and y is parametric. "LEG" and "ARM" define the contact position between the ball-LEG assembly 1670, the idler 1526, and the shift cam 1527. More specifically, LEG is the perpendicular distance between the axis of the ball shaft 3702 of the ball-LEG assembly 1670 to a line passing through the centers of the respective two cams 152 of the ball-LEG assembly 1570. ARM is the distance between the centers of the cams 152 of the ball-leg assembly 1670.

RSF values above 0 are preferred. The CVT100 demonstrates the application of an RSF value equal to about 1.4. Applicants have found that an RSF value of 0 greatly increases the force required to shift the CVT. In general, RSF values above 1.0 and less than 2.5 are preferred.

Still referring to the embodiments shown in fig. 16 and 18-21, in the embodiment of the CVT100 shown, there is a maximum RSF for the maximum gamma angle. For example, an RSF of about 1.6 is maximum for γ equal to +20 degrees. The RSF also depends on the size of the ball 101 and the size of the idler 1526, as well as the position of the cam 152.

The energy can be input as a large displacement and a small force (for a large RSF) or a small displacement and a large force (for a small RSF) according to the energy input to the shift CVT. For a given CVT, there is a maximum allowable shift force and a maximum allowable displacement. Thus, the alternating use provides designers with a variety of design choices for all specific applications. An RSF greater than zero reduces the required shift force by increasing the axial displacement to achieve the required shift ratio. The maximum displacement is determined by the limits of the particular shift mechanism (such as a handlebar or trigger shift in some embodiments), and in some embodiments, is also or alternatively affected by packaging limitations of the CVT 100.

The energy per unit time is another factor. Depending on the power source used to actuate the shift mechanism, a shift ratio for a given application may require a certain level of force or displacement to achieve the shift ratio. For example, in certain applications where a motor-shifted CVT is used, a motor with modulation at low torque may be preferred in some situations. Since the power source is biased toward speed, the RSF is biased toward displacement. In other applications where hydraulic shifting is used, low flow high pressures may be more suitable than high flow low pressures. Thus, depending on the application, one would choose a lower RSF to match the power source.

Not only the idler translation linearly related to γ is a desired relationship. Thus, for example, if idler translation is required to be linearly proportional to CVT ratio, the RSF factor varies with the γ angle or CVT ratio such that the relationship between idler position and CVT ratio is linearly proportional. This is a desirable feature for certain types of control strategies.

Fig. 22-24 illustrate one example of a cage 1589 that may be used in the CVT 1500. The illustrated cage 1589 has two stators 1586 and 1587 connected to each other by a set of stator spacers 1555 (only one shown for clarity). In this embodiment, the stator spacers 1555 are secured to the outer edges of the stators 1586 and 1587. Here, screws attach the spacers 1555 to the stators 1586 and 1587. However, the stators 1586 and 1587 and the spacers 1555 may be configured as other connection methods such as press fitting, screwing, or any other method or device. In some embodiments, one end of the spacers 1555 is permanently affixed to one of the stators 1586 or 1587. In certain embodiments, the spacers 1555 are made of a material that provides structural rigidity. The stators 1586 and 1587 have slots 2202 that guide and support the legs 103 and/or the shaft 3702. In certain embodiments, the legs 103 and/or the shaft 3702 have wheels (item 151 of fig. 11 or equivalent of other embodiments) that ride on the grooves 2202.

Fig. 24 shows the stator 1586 on the side opposite the slots 2202 of the stator 1586. In this embodiment, the holes 2204 receive screws that attach the stator spacers 1555 to the stator 1586. The internal bore 2210 receives screws that attach the stator 1586 to the flange 4206 of the main shaft 105. To make the stator 1586 of some embodiments lighter, material is removed therefrom as shown by the cut 2206 in this embodiment. The stator 1586 may also include additional cutouts 2208, as in this embodiment, to account for weight and clearance of the ball-leg assembly 1670 elements.

Referring now to the embodiment of fig. 25, 26 and 36, an axial force generating mechanism that may be used with the CVT1500 of fig. 15 is described. Fig. 25 and 26 are partially exploded views. Input shaft 1505 inputs torque to the twist plate 1525. The torsion disc 1525 is coupled to a load cam disc 1530 having ramps 3610. As load cam plate 1530 rotates, ramps 3610 actuate rollers 2504, and rollers 2504 ride up ramps 3610 of second load cam plate 1549. Rollers 2504 then wedge into place, compressing between the ramps of load cam disks 1530 and 1540, and transferring both torque and axial force from load cam disk 1530 to load cam disk 1540. In certain embodiments, CVT1500 includes roller retainer 1535 to ensure proper alignment of rollers 2504. The rollers 2504 may be spherical, cylindrical, barrel-shaped, asymmetrical, or any shape suitable for a given application. In some embodiments, each roller 2504 has a separate spring (not shown) attached to the roller retainer 1535 or other structure that biases the roller 1504 above or below the ramp 3610 when desired in some applications. In the illustrated embodiment, input disc 1545 is configured to be coupled to load cam disc 1540 and receive input torque and axial force. The axial force then sandwiches the balls 101 between the input disc 1545, the output disc 1560, and the idler 1526.

In the illustrated embodiment, the load cam disc 1530 is secured to the torsion disc 1525 by a locating pin. However, other methods of securing the load cam disc 1530 to the torsion disc 1525 may be used. Additionally, in some embodiments, the load cam disc 1530 is integral with the torsion disc 1525. In other embodiments, the twist disk 1525 has a ramp 3610 that is machined as a single unit that transmits both torque and axial forces. In the illustrated embodiment, load cam plate 1540 is coupled to input plate 1545 by dowel pins. Further, any other suitable fastening method may be used to couple input discs 1545 to load cam disc 1540. In some embodiments, input disc 1545 and load cam disc 1540 may be an integral unit, in fact embedded within input disc 1545 as ramps 3610. In another embodiment, the axial force generating mechanism may include only one set of ramps 3610. That is, one of the load cam discs 1530 or 1540 does not have a ramp 3610, but rather provides a flat surface for contacting the roller 2504. Similarly, where the bevel is embedded in the twist plate 1525 or the input plate 1545, one of them does not include the bevel 3610. In load cam discs 1530, 1540 in both embodiments where both discs or only one disc has a ramp, ramp 3610 and the flats on the disc without the ramp may be formed to cooperate to match the shape of the roller 2504 surface, thereby partially capturing roller 2504 and reducing the level of surface application.

In certain embodiments, under certain operating conditions, the CVT1500 requires a preload axial force. For example, at low torque inputs, the input disc 1545 may slip over the balls 101 rather than achieving frictional traction. In the embodiment shown in fig. 25 and 26, the axial preload is achieved in part by coupling the torsion spring 2502 to the torsion plate 1525 and the input plate 1545. One end of the torsion spring 2502 fits into a hole 2930 (see fig. 29) of the twist plate 1545, while the other end of the torsion spring 2502 fits into a hole of the input plate 1545. Of course, one of ordinary skill in the art will readily attach the torsion spring 2502 to the input disc 1545 and the twist disc 1525 in a variety of alternative ways. In other embodiments, the torsion spring 2502 can be attached to the roller retainer 1535 and the twist plate 1525 or the input plate 1545. In some embodiments where only one of the twist plate 1525 or the input plate 1545 has a ramp 3610, the torsion spring 2502 connects the roller retainer 1535 to the plate via the ramp.

Referring still to the embodiments illustrated in fig. 15, 25 and 26, as previously described, in certain embodiments, the application of an axial force generates a reaction force that reacts at the CVT 1500. In this embodiment of CVT1500, the ball thrust bearings help manage the reaction forces by transmitting thrust between the hub cap 1460 and the torsion disc 1525. The thrust bearing has a race 1602 that abuts a hub cover 1460, which in this embodiment has a recess near its inner bore for receiving race 1602. The second race 1603 of the thrust bearing is embedded in a groove of the twist disk 1525. In some embodiments, a wave spring 1515 is included between the race 1602 and the hub 1460 to provide an axial preload. In the illustrated embodiment, the bearing 2610 radially supports the hub cap 1460.

Applicants have found that certain configurations of CVT1500 are better suited than others to address the problem of reduced efficiency of CVT1500 due to the understanding herein referred to as bearing drag recirculation. This phenomenon occurs when a bearing is placed between the torsion plate 1525 and the hub cap 1460 to account for the reaction force generated by axial forces.

In certain embodiments, as shown in FIG. 1, needle bearings having a diameter approximately equal to the diameter of the load cam disc 1530 are used to minimize deflection of the end cap 160. In underdrive conditions, the speed of torsion disc 157 (input speed) is greater than the speed of end cap 160 (output speed). In underdrive conditions, the needle bearings (thrust bearings 163 in this embodiment) generate a drag torque opposite the direction of rotation of the twist plate 1525. This drag torque acts on the torsion plate 1525 in a direction opposite to the axial load of the load cam plate 1530 and acts on the end cap 160 in a direction that attempts to accelerate its rotation, thereby acting on the hub shell 138 and the output plate 134, which effects together unload the cam loader 154, thereby reducing the axial force in the CVT 1500. This condition may cause slippage between or among the input disc 110, the balls 101, and/or the output disc 134.

In an overdrive condition, the speed of torsion disc 1525 is greater than the speed of end cap 160 and the needle bearings generate a drag torque acting on torsion disc 1525 in the direction of rotation of torsion disc 1525 and acting on end cap 160 against the output rotation of end cap 160. This results in an increase in the axial force generated in the CVT 1500. Thus, the increase in axial force causes the system to generate a greater drag torque. This feedback phenomenon between axial force and drag torque is a phenomenon known as bearing drag recirculation, which ultimately results in a reduction in the efficiency of the CVT 100. In addition, the drag torque acting against the end cover 160 acts as additional resistance to the output of the CVT100, further reducing its efficiency.

Applicants have discovered various systems and methods that minimize efficiency losses due to bearing drag recirculation. As shown in fig. 25, 26 and 40, rather than using needle bearings configured as described above, in some embodiments the CVT1500 uses roller thrust bearings having races 1602 and 1603. Because the amount of drag torque increases with the diameter of the bearing used, the diameter of the races 1602 and 1603 is less than the diameter of the axial force generating load cam plate 1530, and in some embodiments as small as possible. The diameter in the races 1602 and 1603 can be 10, 20, 30, 40, 50, 60, 70, 80, or 90 percent of the diameter of the load cam plate 1530. In some embodiments, the diameter of the races 1602 and 1603 is between 30 and 70 percent of the diameter of the load cam disc 1530. In other embodiments, the races 1602 and 1603 have a diameter between 40 and 60 percent of the diameter of the load cam disc 1530.

When ball thrust bearings are used, in some embodiments, the rollers and/or races are made of ceramic, the races are lubricated and/or superfinished, and/or the number of rollers is minimized, but the required load capacity is maintained. In some embodiments, deep groove radial ball bearings or angular contact bearings may be used. For particular applications, CVT1500 may use magnetic bearings or air bearings as a means of minimizing bearing drag recirculation. Other methods of reducing the effects of bearing drag recirculation are described below with reference to FIG. 46 in conjunction with alternative embodiments of the input shaft 1505 and the main shaft 105.

Fig. 27-35 illustrate examples of particular embodiments of a torque input shaft 1505 and a twist disk 1525 that may be used with the CVT1500 of fig. 15. Input shaft 1505 is connected to the torsion plate 1525 through a splined bore 2710 in the torsion plate 1525 and a splined flange 2720 in the input shaft 1525. In some embodiments, the input shaft 1505 and the twist plate 1525 are one piece, either made of a single unit (as shown in fig. 1), or wherein the input shaft 1505 and the twist plate 1525 are joined together by a permanent connection means (e.g., welding or any other suitable bonding process). In other embodiments, the input shaft 1505 is operably connected to the torsion plate 1525 via fasteners (e.g., screws, dowel pins, clips, or any other device or method). The particular configuration shown here is preferred in situations where it is desirable to have the input disc 1505 and the torque disc 1525 be separate pieces, which can account for errors and axial displacement due to the load cam disc 1530 growing under load, as well as the breakaway torque through the splined bore 2710 and splined shaft 2720. This configuration is also preferred in some embodiments because it allows for a smaller tooling trade-off, thereby reducing the tooling cost of the CVT.

Referring to fig. 16, 28-32, in the illustrated embodiment, the twist disk 1525 is a generally circular disk having a periphery 3110 and a splined inner bore 2710. One side of the twist plate 1525 has a groove 3205 that receives a thrust bearing race 1603. The other side of the twist plate 1525 includes a seat 3210 and shoulder 3220 for receiving and connecting with the load cam plate 1530. Twist disk 1525 includes a raised surface 3230 that rises up from shoulder 3220, reaches a maximum height in a convex shape, and then falls toward inner bore 2710. In one embodiment of CVT1500, the raised surface 3230 partially supports and constrains the torsion spring 2502, while a set of detents (not shown) hold the torsion spring 2502 in place. In such an embodiment, the locating pin is located in the bore 2920. The twist plate 1525 is shown here with three splines on its splined bore 2710. However, in other embodiments, the splines may be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 or more. In some embodiments, the number of splines is 2 to 7, and in other embodiments, the number of splines is 3, 4, or 5.

In some embodiments, the torsion disc 1525 includes an aperture 2910 for receiving a dowel pin that connects the torsion disc 1525 to the load cam disc 1530. The twist plate 1525 may also have a hole 2930 for receiving one end of the torsion spring 2502. In the illustrated embodiment, there are several apertures 2930 to accommodate different possible configurations of the torsion spring 2502 and to provide for adjustment of the preload level.

The torsion disc 1525 may be any material that is sufficiently rigid and strong to transmit the torque and axial loads expected in a given application. In some embodiments, the material selection is designed to facilitate the reaction force generated by the reaction. For example, depending on the application, hardened steel, aluminum, magnesium, or other metals are suitable, while in other applications plastics are suitable.

Fig. 33-35 illustrate an embodiment of an input torque shaft 1505 for use with the CVT 1500. The torque input shaft 1505 is comprised of a hollow cylinder with a splined flange 2720 at the upper end and a key holder 3310 at the other end. In this embodiment, the keybed 3310 receives a key (not shown) that operatively connects the input shaft 1505 to a flywheel bracket 1510 (see fig. 14, 15), wherein the flywheel bracket 1510 is itself connected to the flywheel 1420. Surfaces 2720 and 3410 are shaped to match splined bore 2710 of torsion disc 1525. Accordingly, the concave surfaces 2720 of some embodiments are preferably equal in number to the number of splines within the splined bore 2710. In certain embodiments, concave surface 2720 may be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, or more. In certain embodiments, the concave surfaces 2720 may be 2-7, and in other embodiments, there are 3, 4, or 5 concave surfaces 2720.

As shown, the input shaft 1505 has several return grooves that help to axially retain various components (e.g., bearings, spacers, etc.) in place. The input shaft 1505 is made of a material that can transmit the desired torque in a given application. In some cases, the input shaft 1505 is made of hardened steel, or other metal alloys, while in other embodiments it is made of aluminum, magnesium, or any plastic or composite material or other suitable material.

Fig. 36 shows a load cam disk 1540 (optionally 1530) that can be used with CVT 1500. Disk 1540 is generally a circular ring having an edge at its outer edge. The belt edge is formed by a bevel 3610. Some ramps 3610 have holes 3620 that receive locating pins (not shown) for connecting load cam disc 1530 to torsion disc 1525 or connecting load cam disc 1540 to input disc 1545. In certain embodiments, ramps 3610 are machined as a single unit with load cam disks 1530, 1540. In other embodiments, ramp 3610 may be separate from the ring-based layer (not shown) and attached thereto by any known fixation method. In the latter case, ramp 3610 and the ring base may be made of different materials and by different machining or forging methods. Load cam plate 1540 may be made of, for example, metal or a composite material.

Referring to fig. 37 and 38, an embodiment of a shaft 3702 is comprised of an elongated cylinder having two shoulders 3704 and a waist 3806. Shoulder 3704 begins at a point beyond the midpoint of the cylinder, extending beyond the bore of ball 101. The shoulder 3704 of the illustrated embodiment is beveled, which helps prevent excessive wear of the bushing 3802 and reduces stress concentrations. The end of the shaft 3702 is configured to connect to a bearing or other device to contact the leg 103. In certain embodiments, shoulder 3704 improves the fit of ball leg assembly 1670 by providing support, stop, and/or tolerance reference points for leg 103. The waist 3806 in some embodiments functions as an oil reservoir. In this embodiment, the bushing 3802 surrounds the shaft 3702 within the bore of the ball 101. In other embodiments, a bearing is used in place of the bushing 3802. In other embodiments, the waist 3806 terminates where the bearing is mounted within the ball 101. The bearing may be a roller bearing, a drawn needle roller bearing, an outer ring needle roller bearing, a journal bearing or a bushing. In some embodiments, the bearing is preferably an outer race needle bearing or a remaining bearing. In an attempt to use a universal friction bearing, the CVT100, 1500 often fails or seizes because the bearings or rolling elements of the bearings displace the balls 101 along the shafts 3702, 102 to the point where they contact the legs 103 and bite into the balls 101. This displacement is believed to be caused by the force or strain wave distributed through the ball 101 during operation. Extensive testing and design has led to this understanding, and the applicant believes that the use of outer race needle bearings or other bearings has significantly and unexpectedly led to longer life and improved durability for particular embodiments of the CVT100, 1500. Embodiments using bushing and journal materials also help reduce failures due to this phenomenon. The bushing 3802 may be replaced by a babbitt lining, for example, coating one or both of the ball 101 or the shaft 3702. In other embodiments, shaft 3702 is made of bronze, providing ball 101 with a bearing surface that does not require bearings, bushings, or other linings. In some embodiments, the balls 101 are supported by outer race needle bearings separated by a spacer (not shown) located in the middle portion of the bore of the balls 101. Additionally, in other embodiments, a spacer is mounted on shoulder 3704 separating the outer race needle bearing from the components of leg 103. The shaft 3702 may be made of steel, aluminum, magnesium, bronze, or any other metal or alloy. In certain embodiments, the shaft 3702 is made of plastic or ceramic material.

One embodiment of the main shaft 105 is shown in fig. 41-43. The main shaft 105 is an elongated body having an inner bore 4305 for receiving a shift rod 112 (see fig. 16 and 40). As used in CVT1500, the main shaft 105 is a single piece shaft that provides support for many of the components of the CVT 1500. In embodiments using a single piece shaft as main shaft 105, main shaft 105 reduces or eliminates tolerance stack-up in certain embodiments of CVT 1500. In addition, the single-piece main shaft 105 provides greater rigidity and stability to the CVT1500 than a multi-piece shaft.

The main shaft 105 also includes a through slot 4204 that receives the shift pin 114 and allows it to move axially (i.e., along the longitudinal axis of the main shaft 105). The dimensions of the groove 4204 are selected to provide shift stops to selectively determine the range of speed ratios for a given application of the CVT 1500. For example, by selecting the appropriate size and/or positioning of the slot 4204, the CVT1500 may be configured to have a lower speed range that is greater than an overdrive range, or vice versa. For example, if it is assumed that the groove 4204 shown in fig. 42 provides a full range in which the CVT1500 can shift, a groove shorter than the groove 4204 will reduce the speed ratio range. If the slot 4204 is shortened on the right side of fig. 42, the underdrive range will be reduced. Conversely, if slot 4204 is shortened on the left side of fig. 41, the overspeed range will be reduced.

In this embodiment, the flange 4206 and the shoulder 4208 extend in a radial direction from the main shaft 105. As described above, the flange 4206 and the shoulder 4208 facilitate the securing of the stator 1586 to the main shaft 105. In some embodiments, the bore of the stator 1586 is sized to fit onto the main shaft 105 such that the shoulder 4208 can be eliminated. In other embodiments, the shoulder 4208 and/or the flange 4206 may be separate portions from the main shaft 105. In this case, shoulder 4208 and/or flange 4206 are coaxially mounted about main shaft 105 and secured thereto by any known means known in the art. In the depicted embodiment, spindle 105 includes a key mount 4202 for receiving a key 1606 that rotatably secures flange 1610 (see FIG. 16). Key 1606 may be a woodruff key. The main shaft 105 of some embodiments is made of a metal suitable in terms of tooling, cost, strength, and stiffness. For example, the main shaft may be made of steel, magnesium, aluminum, or other metals or alloys.

Referring now specifically to fig. 39 and 40, the operation of a hub 1400 having one embodiment of the CVT1500 described above will be described. The freewheel 1420 receives torque from a bicycle chain (not shown). Since the flywheel 1420 is fixed to the flywheel bracket 1510, the flywheel 1420 applies torque to the flywheel bracket 1510, which in turn, the flywheel bracket 1510 transmits torque to the input shaft 1505 via a splined connection (not shown). Input shaft 1505, which runs on needle bearings 4010 and 4020 mounted to main shaft 105, transmits torque to torsion disc 1525 through splined bore 2710 and splined surfaces 2720 and 3410 of input shaft 1505. Needle bearings 4010 are preferably disposed adjacent to or below flywheel holder 1510 and/or flywheel 1420. This arrangement provides adequate support for the input shaft 1505, preventing the radial load of the flywheel carrier 1510 from being transmitted through the CVT 1400 as a bending load. Additionally, in certain embodiments, a shim 4030 is provided between the needle bearings 4010 and 4020. The spacer 4030 is made of, for example, teflon.

As the twist plate 1525 rotates, the load cam plate 1530 attached to the twist plate 1525 follows, such that ramps 3610 actuate rollers 2504. Ponytail 504 rides up ramp 3610 of load cam disk 1540, wedging between load cam disk 1530 and load cam disk 1540. Wedging of rollers 2504 results in both torque and axial force of load cam plate 1530 being transferred to load cam plate 1540. A roller cage 1535 is used to hold the rollers 2504 in proper alignment.

Because load cam plate 1540 is rigidly connected to input disc 1545, load cam plate 1540 transmits both axial force and torque to input disc 1545, and input disc 1545 transmits both axial force and torque to balls 101 through frictional contact. As the input disc 1545 rotates under the torque it receives from the load cam disc 1540, frictional contact between the input disc 1545 and the balls 101 forces the balls 101 to rotate about the shaft 3702. In this embodiment, the shaft 3702 is prevented from rotating about its own longitudinal axis with the ball 101; however, the shaft 3702 may pivot or tilt about the center of the ball 101, such as during a shift.

The input disc 1545, output disc 1560, and idler 1526 are in frictional contact with the balls 101. As the balls 101 rotate on the shaft 3702, the balls 101 apply torque to the output disc 1560, forcing the output disc 1560 to rotate about the shaft 105. Because the output plate 1560 is rigidly connected to the hub shell 138, the input plate 1560 applies an output torque to the hub shell 138. The hub shell 138 is coaxially and rotatably mounted about the main shaft 105. Thus, the hub shell 138 transmits the output torque to the bicycle wheel by a well-known method (e.g., spokes).

Still referring to fig. 39 and 40, the shifting of the ratio of input speed to output speed, and thus input torque to output torque, is accomplished by tilting the axis of rotation of the ball 101, which requires a shift in the angle of the shaft 3702 to be performed. The shift of the transmission ratio comprises performing an axial movement of the shift rod 112 in the main shaft 105, or in the rotation of the shift rod 312 of fig. 3. The shift rod 112 axially translates the pin 114, which pin 114 contacts the shift cam 1527 through the bore 1910 in the extension 1528. Axial movement of the shift pin 114 causes corresponding axial movement of the shift cam 1527. Because the shift cam 1527 is in contact with the leg 103 (e.g., via the cam 152), the leg 103 moves radially as the leg 103 moves along the cam profile 2110. Since the leg 103 is connected to the shaft 3702, the leg 103 serves as a lever for pivoting the shaft 3702 about the center of the ball 101. Pivoting of the shaft 3702 causes the balls 101 to change the axis of rotation, thereby causing a shift in the transmission ratio.

Fig. 44 and 45 illustrate an embodiment of a CVT4400 having an axial force generating mechanism including one load cam plate 4440 acting on an input disc 1545 and another load cam plate 4420 acting on an output disc 1560. In this embodiment, load cam discs 4440 and 4420 include ramps, such as ramps 3610 of load cam discs 1530 and 1540. In this embodiment, neither the input disc 1545 nor the output disc 1560 has a bevel, or is connected to the discs by a bevel. However, in other embodiments, it may be desirable to provide one or both of the input disc 1545 or the output disc 1560 with a disc having a ramp, or to create a ramp on the input disc 1545 and/or the output disc 1560 that cooperates with the load cam discs 4420, 4440. The CVT4400 of certain embodiments also includes a roller retainer 4430 that receives and aligns a set of rollers (not shown) between the load cam plate 4420 and the output disc 1560. In the illustrated embodiment, the roller retainers 4430 move radially on the output disc 1560. Similarly, there is a roller retainer 4410 between the load cam plate 4440 and the input disc 1545. The rollers and discs described with reference to these embodiments may be of any form or shape as described above for the axial force generating means. In certain embodiments, the angle at which the bevel slopes from the disk surface is (between) 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 degrees or more or any portion between these angles.

Fig. 46 shows an embodiment of a CVT 1600 having an input shaft 4605 and a main shaft 4625 adapted to reduce the effects of bearing drag recirculation. The CVT 1600 includes an axial force generator 165 that generates an axial force that is partially reacted by the needle bearing 4620. The hub cap 4660 reacts the drag torque and axial force of the needle bearing 4620. In other embodiments, the needle bearings 4620 are replaced with ball thrust bearings, which in other embodiments have a diameter smaller than the diameter of the needle bearings 4620.

In this embodiment, the main shaft 4625 has a shoulder 4650 that provides a reaction surface for the washer 4615, which may also be a clip (which in some embodiments are all integral), for example. Input shaft 4605 is mounted with an extension 1410 that reacts against bearing 4645. Bearing 4645 may be a thrust bearing. As shown, the input shaft 4605 is a single piece with a drive plate (similar to twist plate 1525). However, in other embodiments, the input shaft 4605 may be connected to the twist disk 1525, for example, by threading, keying, or other fastening means. In the illustrated embodiment, some of the reaction force from the generated axial force is reacted to the main shaft 4625, thereby reducing bearing drag recirculation. In another embodiment (not shown), extension 1410 reacts against an angular face thrust bearing that also supports input shaft 4605 on main shaft 4625. In the latter embodiment, the shoulder 4650 and washer 4615 are not required. Also, the main shaft 4625 is adapted to support and retain an angular face thrust bearing.

In many of the embodiments described herein, lubrication fluid is utilized to reduce friction of bearings supporting many of the elements. Additionally, some embodiments benefit from providing a fluid with a higher traction coefficient to the traction components that transmit torque through the transmission. Such fluids, which in certain embodiments are referred to as "traction fluids," include Santotrac 50, 5CST, available from Ashland oil, OS #155378, available from Lubrizol, IVT Fluid # SL-2003B21-A, available from Exxon Mobile, and any other suitable lubricating oil. In certain embodiments, the traction fluid for the torque transmitting components is separate from the lubrication oil that lubricates the bearings.

Other embodiments of a continuously variable transmission and its components and subassemblies are described with reference to fig. 47-85E. FIG. 47 illustrates a cross-sectional view of a rear bicycle hub that includes a Continuously Variable Transmission (CVT) 4700. As previously mentioned, the CVT4700 and its equivalents may be used in many applications other than bicycles, including, but not limited to, human powered vehicles, light electric vehicles, human-electric hybrid or internal combustion engine powered vehicles, industrial equipment, wind turbines, and the like. Any technical application requiring regulation of mechanical energy conversion between an input source and an output load uses an embodiment of the CVT4700 in its drive train.

It should be noted that references herein to "traction" do not preclude a mode in which power is transmitted primarily or solely through "friction". No attempt is made to establish an absolute distinction between traction and friction drive, which is generally understood to mean a different manner of power transmission. Traction drives typically involve the transfer of power between two elements through shear forces within a thin fluid layer trapped between the elements. Friction is generally common to river which rises in the northeastern part of Anhui Province to transfer power between two elements through frictional forces between the elements. For purposes of this disclosure, it should be understood that CVT4700 may operate in either a traction mode or a friction mode. For example, in embodiments where the CVT4700 is used in a bicycle application, the CVT4700 may sometimes operate in a friction drive and sometimes a traction drive depending on the torque and speed conditions during operation.

As shown in fig. 47, CVT4700 includes a shell or hub shell 4702 connected to a cover or hub cap 4704. The hub shell 4702 and the shell cover 4704 form a housing for enclosing most of the components of the CVT 4700. The primary shaft 4706 provides axial and radial positioning and support for other components of the CVT 4700. For the sake of description, it can be seen that CVT4700 has a variator assembly 4708 as shown in detail view C, an input device assembly 4710 as shown in detail view D, an input side axial force generating device assembly 4712 as shown in detail view E, an output side axial force generating device assembly 4714 as shown in detail view F, a shift lever and/or shifter interface subassembly 4716 as shown in detail view G. These subassemblies are now described in further detail.

Referring now to fig. 48A-48G, in one embodiment, the variator assembly 4708 includes a plurality of traction power rollers 4802 in contact with an input traction ring 4810, an output traction ring 4812, and a support element or idler 4814. The shift lever 4816 is threaded into a shift lever nut 4818 located between the shift cams 4820 and adapted to contact the shift cams 4820. Idler bushing 4832 is guided by main shaft 4706 and contacts shift rod nut 4818. Shift rod nut washers 4819 are coaxially mounted about the main shaft 4706 and are located between the shift cams 4820. The shift cam 4820 contacts the cam roller 4822. One end of each of several legs 4824 is attached to a cam roller 4822. The other end of each leg 4824 is connected to a power roller axle 4826, which axle 4826 provides a tiltable axis of rotation for the power roller 4802. In some embodiments, power roller shaft 4826 is free to rotate relative to leg 4824 through the use of, for example, bearings, but in other embodiments, power roller shaft 4826 is rotationally fixed relative to leg 4824. In the embodiment shown in fig. 48A, the idler 4814 bears against bearing balls 4824 located between the idler 4814 and the shift cam 4820.

In some cases, for purposes of description only, the power roller 4802, the power roller axle 4826, and the cam roller 4822 are collectively referred to as a power roller leg assembly 4830. Similarly, the idler 4814, shift cams 4820, idler bushing 4832, shift rod nut washer 4819, and related other components are sometimes referred to together as an idler assembly 4834. As best shown in fig. 48B, the stator plate 4836 and the stator plate 4838 are coupled to a plurality of stator bars 4840 to form a cage or support 4842.

Figures 48D-48E illustrate one embodiment of an idler assembly 4834. In addition to the components described above, in some embodiments, the idler assembly 4834 further includes a positioning ring 4844 and a thrust washer 4846. The positioning ring 4844 is mounted in a positioning ring groove of the idler bushing 4832 with the thrust washer 4846 located between the positioning ring 4844 and the shift cam 4820. In some embodiments, as shown in fig. 48E, the ball bearings 4824 may be housed within a bearing cage 4848. Fig. 48F-48G show the idler assembly assembled on the spindle 4706.

Referring now to fig. 49A-49F, one embodiment of the power input device assembly 4710 is now described. In one embodiment, the input device assembly 4710 includes a flywheel 4902 connected to one end of an input drive 4904. In some embodiments, the flywheel 4902 may be, for example, a one-way clutch. A twist disk 4906 is connected to the other end of input drive 4904. Cam driver 4908 is connected to torsion disk 4906. In the illustrated embodiment, cam driver 4908 and torsion disk 4906 have cooperating splines, and cam driver 4908 and torsion disk 4906 are mounted coaxially.

In the illustrated embodiment, the input drive 4904 bears against ball bearings 4910A, 4910B. A set of ball bearings 4910A rest on a race provided by bearing nut 4912. The second set of ball bearings 4910B rests on a race 4910B provided by a bearing nut 4914. A bearing screw 4912 and a bearing race 4914 are mounted on the main shaft 4706. In one embodiment, bearing nut 4912 is threaded onto main shaft 4706 and bearing race 4914 is press fit onto main shaft 4706. As shown in fig. 49A, input drive 4904, bearing screw 4912, and bearing race 4914 are configured to provide the function of an angular surface contact bearing.

The hub shell 4702 rests on a radial ball bearing 4916, which bearing 4916 is supported on the input drive 4904. Seal 4918 is located between bearing race 4914 and drive 4904. Another seal 4921 is located between the input drive 4904 and the bearing nut 4912. To react certain bearing loads generated in the CVT4400, a thrust washer 4922 and a needle bearing 4924 are interposed between the cam driver 4908 and the hub shell 4702. In this embodiment, the hub shell 4702 is adapted to transfer torque to and from the CVT 4700. Accordingly, in certain embodiments, the hub shell 4702 may be configured to both transmit torque and react axial loads as the thrust washer 4922 and/or needle bearing 4924 transmit axial forces to the hub shell 4702.

Referring now to FIGS. 50A-50B, one embodiment of the input side axial force generating device assembly (input AFG)4712 is now described. The input AFG 4712 includes a cam driver 4908 in contact with a plurality of load cam rollers 6404. In this embodiment, the rollers 6404 also contact a set of ramps 6202 (see fig. 62) that are integral with the input traction ring 4810. As cam driver 4908 rotates about spindle 4706, cam driver 4908 causes roller 6404 to ride up ramp 6202. This arching action actuates roller 6404, generating an axial force, as roller 6404 is compressed between cam driver 4908 and ramp 6202. This axial force acts to clamp or push the input traction ring 4810 against the power rollers 4802. In this embodiment, the axial forces generated are reacted through needle bearing 4924 and thrust washer 4922 to hub shell 4702; however, in some embodiments, thrust washer 4922 is not used, and an integral equivalent bearing race is provided for hub shell 4702. As shown, needle bearing 4924 is located between load cam driver 4908 and thrust washer 4922.

Referring now to FIG. 51, one embodiment of an output side axial force generating device assembly (output AFG)4714 is illustrated. Similar to the load cam rollers 6404 described above, a set of load cam rollers 6405 are positioned and supported within the roller cage 5005 similar to the roller cage 5004. Rollers 6405 are interposed between the output traction ring 4812 and the hubcap 4704. In certain embodiments, the face 5152 of the hubcap 4704 is adapted to be a reaction surface against which the rollers 6405 can act. In one embodiment, reaction face 5152 is planar; however, in other embodiments, the reaction surface 5152 has a load cam ramp, such as ramp 6202. Fig. 51 shows the clearance between the rollers 6405 and the hubcap 4704; however, after the CVT4700 is assembled, the gap closes when the torsion springs 5002, 5003 cause the rollers 6404, 6405 to ride up the ramps 6202, 6203 on the input and output traction rings 4810, 4812, respectively. Once the output traction ring 4812 rotates about the main shaft 4706 under torque transmitted by the power rollers 4802, the rollers 6405 ride further up 6203, creating additional axial force as the rollers 6405 are further compressed between the output traction ring 4812 and the hubcap 4704.

Fig. 52A-52B illustrate one embodiment of a powered roller leg assembly 4830. Power roller leg assembly 4830 includes power rollers 4802 mounted on needle bearings 5202. A shim 5204 is provided on each end of the roller bearing 5202, one shim 5204 being provided between the roller bearings 5202. The bearings are mounted on roller shafts 4826, with the ends of roller shafts 4826 mounted in the bores of legs 4824. The end of roller axle 4826 extends beyond leg 4824 and receives oblique roller 5206. One end of leg 4824 is adapted to receive cam roller 4822. To guide the leg 4824 and support reaction forces during CVT4700 shifting, the leg 4824 may also be adapted to receive a shift guide roller 5208. As shown, the guide rollers 5208 react a portion of the shifting force to the grounded cage 4842 (see fig. 48B), among other things. Therefore, the position of the guide roller 5208 on the leg 4824 is mainly determined such that the guide roller 5208 is movable together with the leg 4824 while contacting the reaction surface 5708 of the stator plates 4836, 4838 for all the inclination angles of the power roller shaft 4826 (see fig. 57B).

Fig. 53 shows an embodiment of a power roller 4802. In a bicycle application, one embodiment of power roller 48024 is a 28 millimeter (mm) diameter, AFBMA Grade 25, bearing quality SAE52100, bearing ball through hardened 62-65 HRC. The central hole 5302 of the power roller 4802 is about 9 mm. In some embodiments, the surface texture of the powered rollers 4802 is up to about 1.6 microns. In the illustrated embodiment, the power roller 4802 includes a chamfer 5304 at the end of the bore 5302 to facilitate assembly, improve fatigue life of the power roller 4802 and reduce damage to the edges of the bore 5302 during handling, shipping, or assembly. In one embodiment, beveled surface 5304 is angled at about 30 degrees from the longitudinal edge of aperture 5302. One way to machine the power rollers 4802 is to form holes 5302 in a relatively soft material (e.g., steel 8260, soft alloy steel 52100, or other bearing steel) and then harden or case harden the power rollers 4802 to a desired hardness.

54A-54C illustrate an embodiment of a roller axle 4826 having a generally cylindrical middle portion 5402 and generally cylindrical tip portions 5404A, 5404B with a smaller diameter than middle portion 5402. In one embodiment, roller axle 4826 is approximately 47mm long from one end to the other for applications such as bicycles. The middle portion 5402 is about 30mm long, while the end portions 5405A, 5405B are about 8 or 9mm long. It should be noted that the lengths of the end portions 5405A and 5404B need not be equal to each other. That is, roller axle 4826 need not be symmetrical about the middle of middle portion 5402. In one embodiment, the diameter of the middle portion 5402 is about 6mm and the diameter of the end portions 5404A, 5404B is about 5 mm. Roller shaft 4826 may be fabricated from a steel alloy (e.g., AISI 8620, SAE 8620H, SAE 4130, SAE 4340, etc.) having a surface hardness of about 55-62HRC with an effective depth of at least 0.5 mm.

FIG. 55 shows a cross section of a powered roller axle 4827 similar to roller axle 4826. The power roller shaft 4827 is characterized by a countersink 5502 and a chamfer 5504. During assembly of the power roller shaft 4827 with the skew roller 5206, the countersunk bore 5502 may radially expand to provide a securement feature for the skew roller 5206. This configuration reduces or eliminates the need for a retaining ring or other retaining device for securing the skew roller 5206 to the power roller axle 4827.

Fig. 56A-56B illustrate some components of a leg assembly 5600. The leg portion 4824 is adapted to receive a guide roller pin or shaft 5602 in a bore 5604. The guide roller shaft 5602 extends beyond the end of the bore 5604 to provide support for the shift guide roller 5208. The leg portion 4824 may also be adapted to receive a cam roller pin or shaft 5606 for supporting the cam roller 4822. In the illustrated embodiment, the roller shaft 5606 does not extend beyond the edge of the leg portion 4824. The leg portions 4824 have fingers or extensions 5608A, 5608B, each having a hole 5610 for receiving a cam roller shaft 5606. The end of the leg portion 4824 opposite the leg extensions 5608A, 5608B has a bore 5612 for receiving a roller axle 4826.

In certain embodiments, the guide roller shaft 5602 and the bore 5604 are sized such that the guide roller shaft 5602 is free to rotate on the bore 5604, i.e., there is a clearance fit between the guide roller shaft 5602 and the bore 5604. In such embodiments, the shift guide roller 5208 can be press fit onto the guide roller axle 5602. Similarly, in certain embodiments, the cam roller shaft 5606 and the bore 5610 are sized to be a clearance fit with respect to one another. The cam roller 4822 is press fit onto the cam roller shaft 5606. This arrangement of free rotation of the guide roller shaft 5602 and the camroller shaft 5606 in the holes 5604, 5610, respectively, for a particular application improves the stability of the leg assembly 5600 during operation of the CVT 4700. In addition, since the shift guide roller 5208 and the cam roller 4822 are press-fitted to the guide roller shaft 5602 and the cam roller shaft 5606, respectively, it is not necessary to fix the shift guide roller 5208 and the cam roller 4822 to their respective shafts by, for example, clips.

In one embodiment, the leg portions 4824 are about 26mm long, about 8mm wide, and about 6mm thick, with the thickness being measured transverse to the longitudinal axis of the cam roller shaft 5602. In certain embodiments, the diameter of aperture 5612 is about 4-5mm and the diameters of apertures 5604 and 5610 are about 2-3 mm. In one application, the leg portion 4824 may be made from alloy steel SAE 4140HT by hardening to HRC 27-32. In certain embodiments, the leg portions 4824 are made of any one of a magnesium alloy, an aluminum alloy, a titanium alloy, or other lightweight material or alloy.

In certain embodiments, shift cam roller 4822 may be made of a pre-hardened alloy steel AISI4140RC 34. For example, in some embodiments, the shift cam rollers 4822 can have an outer diameter of about 7-8mm, an inner diameter of about 2-3mm, and a thickness of about 3 mm. The cam roller shaft 5606 may be, for example, a dowel having a length of about 6mm and a diameter of about 2-3 mm. In some embodiments, the shift cam roller 4822 can have a crown on its functional surface.

For example, the guide roller shaft 5602 may be formed of alloy steel SAE52100 hardened and tempered to RC 55-60, or alloy steel SAE 1060 hardened and tempered to RC 55-60, or alloy steel SAE 8620, 8630 or 8640 case hardened to RC 55-60 and effective depth 0.2-0.8 mm. In certain embodiments, the guide roller shaft 5602 is about 15mm long and has a diameter of about 2-3 mm. In some embodiments, the shift guide roller 5208 has about the same size and material characteristics as the shift cam roller 4822.

Referring to fig. 52A, in certain embodiments, the skew roller 5206 may be made from a pre-hardened alloy steel AISI4140 and hardened to HRC 27-32. For example, the skew roller 5206 can have an outer diameter of about 8-9mm, an inner diameter of about 4-5mm, and a thickness of about 2-3 mm.

Referring now to fig. 57A-57E, one embodiment of a stator plate 4836, 4838 is now described. In some embodiments, the stator plates 4836, 4838 are identical; therefore, for the sake of description, only one stator plate will be described herein. The stator plate 4836 is typically a plate or frame that supports and guides the skew rollers 5206 and the shift guide rollers 5208. The stator disk 4836 includes an outer ring 5702 having a plurality of through holes 5704 that receive stator spacers or rods 4840 (see fig. 48B). The stator plates 4836 include a central bore 5706 for coaxially mounting the main shaft 4706. In certain embodiments, the central bore 5706 is adapted to be tapped by a pull pin and held in place by a pull pin surface on the main shaft 4707 (see, e.g., fig. 66A-66D). The stator plate 4836 includes a surface 5708 that is generally concave and adapted to support the shift guide rollers 5208 when the CVT4700 is shifted. In addition, the stator plate 4836 is provided with reaction surfaces 5710 radially disposed about the central bore 5706 for reacting forces transmitted through the oblique rollers 5206 when the CVT4700 is in operation.

Due to the torque and reaction power generated during operation of CVT4700 at power roller leg assembly 4830, in certain embodiments, it is preferred that reaction surface 5710 have some amount of offset in its placement around the circumferential direction of stator disk 4836. In other words, referring to fig. 57C and 57E, the lines 5712, 5714 extending from the edges 5716, 5718 of the reaction 5710 on one side of the stator plate 4836 do not coincide with (i.e., are offset from) the edges 5720, 5722 of the surface 5710 on the opposite side of the stator plate 4836. The offset shown in fig. 57E is exaggerated for clarity. In certain embodiments, the offset is about 0.05 to about 0.6mm, preferably about 0.10 to about 0.40mm, and more preferably about 0.15, 0.17, 0.20, 0.23, 0.25, 0.28, 0.30, 0.33, or 0.36 mm. In other embodiments, the stator offset may be obtained by angularly angling the respective stator disks 4836, 4838 relative to each other. In other words, when assembled, the stator offset is introduced by offsetting the edges 5716 and 5718 of each stator disk 4836, 4838 relative to the corresponding edge of the other stator disk 4836, 4838 by the angular misalignment of the stator disks 4836, 4838 relative to each other. In the latter method of stator offset, it is not necessary that both stator plates 4836, 4838 have non-coincident edges 5716, 5718 with edges 5720, 5722. The angular offset between the stator plates 4836, 4838 is about 0.1 to 0.5 degrees, more preferably 0.15 to 0.40 degrees for certain applications.

In one embodiment, the stator disk 4836 has an outer diameter of about 92mm and a central bore 5706 of about 14-15mm diameter. Surface 5708 has an annulus pitch circle radius of about 37mm relative to the central axis of stator plate 4836. For example, stator disk 4836 may be fabricated from alloy steel AISI4130H, 20 RC. In certain embodiments, the stator plate 4836 is made of magnesium alloy, aluminum alloy, titanium alloy, or other lightweight material. Cutouts 5724 are formed to remove material from the stator plate 4836 for the purposes of mass reduction and lubrication flow. In certain embodiments, stator disk 4836 may be made of a hardenable alloy, such as AISI 8260, such that surface 5708 and surface 5710 may be selectively hardened to, for example, 45 RC.

Another embodiment of a stator plate 5800 is shown in fig. 58A-58D. Because stator disc 5800 and stator disc 4836 have common design features, those features relating to stator disc 5800 will not be described again, but are identified by the same reference numerals. Stator plate 5800 includes shift guide surface 5708, oblique roller reaction surface 5710, central aperture 5706, and material cutout 5724. In addition, stator plate 5800 includes a coupling extension 5802 integrally formed with outer ring 5702 and extending substantially perpendicularly from outer ring 5702. During assembly, the coupling extensions 5802 of the stator disc 5800 mate with corresponding extensions of the cooperating stator disc 5800 to form a cage similar to the cage 4842 shown in fig. 48B. In one embodiment, the cooperating connecting extensions 5802 are connected by suitable fastening features or means, such as by suitably sized dowel pins (not shown). The locating pins are mounted within holes 5804 of the connecting extensions 5802. In other embodiments, linking extension 5802 extends from stator disc 5800 to, for example, a stator frame (not shown) similar to stator disc 5800, but stator disc 5800 is devoid of linking extension 5802. And, the stator plates are adapted to be connected to the connection extensions 5802 by suitable fastening means (e.g., screws, bolts, welding, etc.). In certain embodiments, stator disc 5800 has an offset surface, as described above with reference to stator disc 4836 and illustrated by lines 5906 and 5808 in fig. 58C.

Fig. 59 illustrates one embodiment of a stator bar 4840 used with stator plates 4836 and 4838 to form a support 4842 (see fig. 48B). The stator bar 4840 includes a waist portion 5902 that transitions into a shoulder portion 5904, the shoulder portion 5904 transitioning into a generally cylindrical end portion 5908, the outer diameter of the end portion 5908 being less than the outer diameter of the shoulder portion 5904. In certain embodiments, the end portion 5908 is provided with a counterbore 5908, the counterbore 5908 expandable to retain the stator bar 4840 in the stator 4836, 4838 during assembly. In some embodiments, the end portion 5908 is adapted to fit within the stator plate connection aperture 5704 (see fig. 57A).

In a particular application, the stator bar 4840 may be made of alloy steel SAE1137 with a 20RC surface. In certain embodiments, the stator bar 4840 is made of magnesium alloy, aluminum alloy, titanium alloy, or other lightweight material. In some embodiments, the stator bars are about 55-56mm long, the end portions 5908 are about 5-7mm long, and the shoulder portions 5904 are about 6-8mm long. The diameter of the end portion 5908 is about 4.5-6.5mm, the diameter of the shoulder portion 5904 is about 6.5-7.5mm, and the diameter of the waist portion 5902 at its narrow point is about 3-4 mm.

FIG. 60 illustrates one embodiment of a shift rod nut 4818 that may be used with the same shift rod 4816 shown in FIGS. 61A-61B. In the illustrated embodiment, the shift rod nut 4818 is a generally rectangular prism 6002 having a threaded bore 6004. It should be noted that the shift lever 4818 need not have a generally rectangular prism as shown, but may be asymmetric, have rounded edges, be cylindrical, etc. The shift rod nut 4818 is adapted to engage the idler bushing 4832 in performing axial movement of the shift cam 4820 (see fig. 48A). In one embodiment, shift rod nut 4818 is approximately 19-20mm long, 8-10mm thick, and 8-10mm wide. The threaded hole is about 6-8mm in diameter, for example, having a 4-inch ya-meter thread of 1/4-16. In certain applications, the shift rod nut 4818 may be made of bronze, for example.

61A-61B, in one embodiment, the shift rod 4816 is a generally elongated cylindrical rod having one threaded end 6102 and a splined end 6104. The threaded end 6102 is adapted to mate with a shift rod nut (e.g., shift rod nut 4818 described above). The splined end 6104 is adapted to mate with a shift mechanism (not shown), such as a pulley, that causes the shift lever 4816 to rotate. The shift lever 4816 also includes a cylindrical middle portion 6106, a shift lever flange 6108, and a shift lever neck 6110. A shift rod flange 6108 engages the main shaft 4706 and a shift rod holder nut 6502 (see fig. 65A). The shift rod neck 6110 is adapted to receive and support a shift rod retainer nut 6502 (see fig. 47 and 65A). It should be noted that the intermediate portion 6106 may also have a shape such as a rectangle, hexagon, or the like, in addition to a cylindrical shape. In certain embodiments, the shift lever 4816 may be generally hollow and/or made of multiple portions adapted to be secured to one another. As shown in fig. 61A-61B, wherein shift lever 4816 may be provided with a guide tip 6112 adapted to facilitate engagement of shift lever 4816 into shift lever nut 4818. During assembly, the pilot end 6112 guides the threaded end 6102 of the shift rod 4816 into the bore 6004 of the shift rod nut 4818.

For some applications, the shift rod 4816 is approximately 130mm long, the threaded end 6102 is approximately 24-26mm long, and the splined end is approximately 9-11mm long. The shift rod 4816 is approximately 6-8mm in diameter. Certain embodiments of the shift rod flange 6108 are approximately 8-9mm in diameter and approximately 3-4mm thick. In certain embodiments, shift rod 4816 may be made of alloy steel AISI 1137, such as with 20 HRC. In certain embodiments, the stator bar 4840 is made of magnesium alloy, aluminum alloy, titanium alloy, or other lightweight material.

Referring now to fig. 62A-62B, one embodiment of a traction ring 4810, 4812 (see fig. 48A) is shown. In the embodiment of CVT4700 shown in fig. 47, the input traction ring 4810 and the output traction ring 4812 are substantially similar to each other. Thus, the following description generally relates to the traction ring 6200, which may be an input traction ring 4810 or an output traction ring 4812. The traction ring 6200 is generally a circular ring having a set of sloped surfaces 6202 on one side of the ring. In some embodiments, the ramp 6202 may be unidirectional; while in other embodiments, the ramp 6202 may be bi-directional. The unidirectional bevel facilitates torque transfer and axial force generation in only one direction of torque input. The bi-directional ramps facilitate torque transfer and axial force generation in the forward or reverse direction of the torque input. The side of the ring opposite the ramp 6202 includes a tapered traction or friction surface 6204 for transmitting or receiving power from the power rollers 4802. In this embodiment, the traction ring 6200 includes a groove or slot 6206 for receiving and supporting the torsion spring 5002. In some embodiments, the slot 6206 includes a bore 6213 (see fig. 62E) for receiving and retaining the first torsion spring end 6302 (see fig. 63C).

In one embodiment, the traction ring 6200 has an outer diameter of about 97-100mm and an inner diameter of about 90-92 mm. In some embodiments, the traction ring 6200 includes about 16 ramps, each ramp having an inclination of about 10 degrees. In certain embodiments, the ramp is helical and has a lead equivalent of about 55-56mm over a 360 degree range. In this embodiment, the dimensions of the groove 6206 are approximately 3.4-4.5mm wide and 2-3mm deep. The traction surface 6204 may be a plane inclined approximately 45 degrees from vertical, in this case, extending radially from the longitudinal axis of the CVT 4700. In certain embodiments, the traction ring 6200 may be made of, for example, alloy steel AISI52100, bearing steel heated to HRC 58-62, while in other embodiments, the hardness of the traction surface 6204 is at least HRC 58, 59, 60, 61, 62, 63, 64, 65, or higher.

With reference to fig. 63A-63F, the torsion spring 5002 will now be described. Torsion spring 5002 is typically a torsion spring having about 2 turns; however, in other embodiments, the torsion spring 5002 can have more or less turns than 2 turns. The first torsion spring end 6302 is adapted to engage a retention feature in the traction ring 6200. The second torsion spring end 6304 is adapted to engage the retention slot of the load cam roller retainer 5004 (see fig. 48C). As best shown in fig. 63E, the second torsion spring end 6304 includes an auxiliary retaining bend 6306 adapted to ensure that the second torsion spring end 6304 is not easily disengaged from the roller cage 5004. Fig. 63B illustrates torsion spring 5002 in a relaxed or free state, fig. 63D illustrates torsion spring 5002 partially stressed, and fig. 63F illustrates torsion spring 5002 in a fully stressed state.

In one embodiment, the torsion spring 5002 has a pitch diameter of about 110-. The torsion spring 5002 of certain embodiments is a wire having a diameter of about 1-2 mm. The first spring end 6302 has a straight portion 6303 that is about 12mm long, and a curved portion 6305 that is 95 degrees from the straight portion 6303 and has a length of about 4 mm.

Assists in keeping the bend 6306 bent toward the center of the torsion spring 5002 at an angle of about 160 degrees relative to the tangent of the torsion spring 5002. In certain embodiments, the secondary retention curve 6306 is about 5.5-6.5mm long. Secondary retention bend 6306 is then over-bent to a second bend 6307 that is approximately 6mm long and approximately 75-80 degrees relative to the parallel to secondary retention bend 6306. While the torsion spring 5002 of certain embodiments is made of a resilient material capable of forming a spring, in certain applications the torsion spring 5002 is made of, for example, alloy steel ASTM a228, XLS C wire, or SS wire.

Referring now to fig. 64A-64D, the roller cage assembly 5004 is now described. The roller cage assembly 5004 includes a roller retainer ring 6402 adapted to receive and retain a plurality of load cam rollers 6404. The roller retainer ring 6402 transitions into a generally circular ring retainer extension 6404 extending at about 90 degrees from the roller retainer ring 6402. In some embodiments, the retaining extension 6406 is adapted to fit over the traction rings 6200, 4810, 4812 (see fig. 48A) to partially and positively retain the torsion spring 5002 in the groove 6206 (see fig. 62E). In the illustrated embodiment, the retaining extension 6406 includes a retaining slot 6408 for receiving and retaining the second torsion spring end 6304 (see fig. 50B).

To ensure proper preload of the CVT4700, and an initial state of the rollers 6404 to the axial forces generated during operation, in certain embodiments, the roller cage 5004, rollers 6404, torsion spring 5002, and input ring 4810 are configured as follows. Referring to fig. 64E-64H, the depth of the groove 6206 of the traction ring 6200, the diameter of the torsion spring 5002 in its free state, the length and wire diameter of the torsion spring 5002, and the diameter of the retaining extension 6406 are selected such that expansion of the torsion spring 5002 in the groove 6206 is limited by the retaining extension 6406 such that the partially unwound torsion spring 5002 biases the roller cage 5004 and rollers 6404 to an upwardly arching slope 6202 and to rest substantially on a planar portion of the traction ring 6200, which portion is located between the inclined portions 6405 of the slope 6202 (see fig. 64F).

When the CVT4700 is assembled, the roller cage 5004 rotates relative to the traction ring 6200, thereby tightening the torsion spring 5002 (see fig. 64H) until the rollers 6404 substantially reach the interrogation portion 6407 of the ramp 6202. Among other things, this assembly process ensures that the torsion spring 5002 is preloaded to bias the roller 6404 against the ramp 6202 so that the roller 6404 is properly actuated for the duration of the CVT4700 operation. Additionally, the assembly structure and assembly process facilitates absorbing tolerances that are mandated during assembly of the CVT 4700. It can be seen that the torsion spring 5002 is sized differently in partially wound (fig. 64F) and fully wound (fig. 64H) configurations for each subassembly of the roller cage 5004, rollers 6404 and traction ring 6200. With the advantage of the winding and unwinding of torsion spring 5002, the tightness or looseness of CVT4700 can be adjusted when the hub shell 4702 is connected to the hub shell cover 4704 because torsion spring 5002 is contained between the cage roller extensions 5004 and the traction ring 6200.

The shifter/shift lever interface subassembly 4716 is now described with reference to fig. 65A-65C. Among other things, the shift interface 4716 is used to cooperatively actuate a shift lever 4816 with a shift mechanism (not shown) to change the gear ratio of the CVT 4700. The shift interface 4716 also functions to retain the shift rod 4816 and limit axial displacement of the shift rod 4816. In the illustrated embodiment, the shift interface 4716 includes a shift rod retainer nut 6502 adapted to receive a shift rod 4816 and to fit around the main shaft 4706. Wherein the shift interface 4716 further comprises a nut 6504 adapted to be threaded onto a shift rod holder nut 6502 to connect the main shaft 4706 to a dropout (not shown) of the bicycle and to prevent disengagement of the shift rod holder nut 6502 from the main shaft 4706 during operation of the shift mechanism. As shown in fig. 65A, the shift interface 4716 may also include an O-ring 6506 for providing a seal between the shift rod retainer nut 6502 and the shift rod 4816.

As shown in fig. 65B-65C, a rudimentary example of a shift rod holder nut 6502 includes a flange 6508 having a plurality of through-holes 6510. The through-hole 6510 facilitates attachment of the printer mechanism to the shift retaining nut 6502 and provides for calibration of the shift mechanism for assembly, adjustment, calibration or other purposes. An inner diameter 6517 of the flange 6508 is adapted to cooperate with the shaft 4706 to axially restrain the shift rod 4816. The shift rod holder nut 6502 includes a hexagonal extension 6514 adapted to receive a fastening tool. In other embodiments, extensions 6514 may have other shapes (e.g., triangular, square, octagonal, etc.) suitable for use with other general or special purpose fastening tools, such as hex nuts sized to be adjusted by a tool that is commonly used in stores, such as a bicycle pedal wrench or other such tool for a particular application. The shift rod holder nut 6502 has a threaded outside diameter 6513 for receiving the nut 6504. This configuration of the nut 6504 threaded onto the shift rod holder nut 6502 facilitates reducing the axial dimension of the CVT4700, which may be advantageous in certain applications of the CVT 4700.

The shift rod holder nut 6502 is also provided with a threaded inside diameter 6512 that threads onto the main shaft 4706. In this embodiment, the shift rod holder nut 6502 additionally has a groove 6516 adapted to receive an O-ring 6506 (see fig. 65A) for providing a seal between the shift rod holder nut 6502 and the main shaft 4706. In one embodiment, the outer diameter of the flange 6508 is about 38mm and the thickness of the flange 6508 is about 1-3 mm. For some applications, the threaded portions 6512, 6513 may have a length of about 8-10mm, the recesses 6516 may have a diameter of about 8-10mm, the central bore 6518 of the extension 6514 may have a diameter of about 5.5-7.5mm, and the extension 6514 may have a length of about 2-4 mm. In certain embodiments, shift rod retainer nut 6502 is made of, for example, powdered metal alloy steel FN-25, or in other embodiments, SAE1137 steel. However, the shift rod holder nut may also be made of other materials.

Referring now to fig. 65D-65G, another embodiment of an array shift rod retainer nut 6550 is shown. The shift rod holder nut 6550 has a recess 6516, a threaded outer diameter 6510, a threaded inner diameter 6512, and an extension 6514, all of which are substantially similar in form and function to like-numbered features described above with reference to fig. 65B-65C. The shift rod holder nut 6550 includes a support extension 6520 adapted to position and/or support a portion of a shift mechanism, such as a pulley.

The shift rod holder nut 6550 also includes a splined side 6522 and a smooth side 6524. Splined side 6522 includes a splined profile formed on a cylindrical portion of flange 6521 that faces extension 6514. Splined side 6522 is adapted to mate with a shift mechanism (not shown), and splined side 6522 provides a similar function to through-hole 6510 of flange 6508 described above. That is, the splines of spline side 6522, among other things, facilitate positioning and/or calibration of the shift mechanism.

Splined side 6524 is provided with a smooth circumferential profile that facilitates engagement of a housing (not shown) of the shift mechanism; the shell bite is around the flange 6521 and is frictionally or otherwise secured by the smooth surface 6522. In certain embodiments (not shown), splined side 6522 extends completely through the circumference of flange 6521. It should be noted that the profile of splined side 6522 has a different shape than that shown in fig. 65D-65G. For example, the profile may be square splines, V-grooves, keyways or any other suitable shape.

65H-65K illustrate yet another embodiment of a shift rod holder nut 6555. Features of the shift rod holder nut 6555 that are substantially identical to the shift rod holder nut 6550 are identified with the same reference numerals. The shift rod holder nut 6555 has a flange 6525 that includes a plurality of extensions 6526. In some embodiments, the extensions 6526 are integral to the flange 6525, while in other embodiments, the extensions 6526 are separate pins or dowels that are received within corresponding apertures of the flange 6525. Extension 6526 is used in some way to facilitate positioning and/or calibration of the shift mechanism coupled to shift lever 4816. It should be noted that in the above described embodiments, or other equivalent embodiments, the same and/or different profile distributions may be used for the mechanisms that facilitate positioning and/or calibration of the shifter. The distribution of the extensions 6526 may form a circle (as shown in fig. 65H), or may form other geometric shapes, such as a square, triangle, rectangle, or any regular or irregular polygon. Further, the extension 6526 may be positioned at any radius of the flange 6525.

Referring now to fig. 66A-66D, one embodiment of the spindle 4706 is described. The main shaft 4706 has a first end with a flat portion 6602 and a second end with a flat portion 6604, wherein a central portion of the main shaft 4706, which flat portion 6004 is for receiving, for example, a mounting bracket, frame or frame element (e.g., a bicycle fork), has a through slot 6606 for receiving a shift lever nut 4818. In certain embodiments, the main shaft 4706 is provided with a central bore 6622 adapted to receive, for example, a shift lever 4816. As shown in fig. 66C, the central bore 6622 needs to pass through the entire length of the main shaft 4706. However, in other embodiments, the central bore 6622 may pass through the entire length of the main shaft 4706 to provide, for example, a service or lubrication hole. In this embodiment, one end of central bore 6622 has a counter bore 6624 adapted to mate with shift rod flange 6108. In certain embodiments, the depth of the counter bore 6624 is selected to substantially reduce the gap size for a given flange 6108 thickness. That is, counterbore 6624 and flange 6108 are machined to minimize the gap between counterbore 6624 and flange 6108 to a gap that allows rotation of shift rod 4816 in its position retained by shift rod retainer nut 6502. In certain embodiments, the depth of the counter bore 6624 exceeds the thickness of the flange 6108 by no more than 1.5 mm. In certain embodiments, the thickness of the flange 6108 is less than the depth of the countersink by 1.0mm, preferably less than 0.5mm, and more preferably less than 0.025 mm.

The main shaft 4706 also includes a knurled or splined surface 6608 that engages the stator plates 4836 and 4838. In certain embodiments, the main shaft 4706 includes a debris port or slot 6610 shaped or adapted to capture material cut from the stator plates 4836, 4838 when the stator plates 4836, 4838 are pressed into the main shaft 4706 in the form of a self-pulling pin. Referring additionally to fig. 47, in one embodiment, the main shaft 4706 features a snap ring groove 6612 for receiving a snap ring (shown in fig. 47, but not labeled) that provides axial positioning to the sub-disk 4836. The mast 4706 may also have a seal mount 6614 for the seal 4720. In the embodiment shown in fig. 66B, the main shaft 4706 includes a bearing guide portion 6616 for supporting the bearing 4718. In the illustrated embodiment, near the bearing guide portion 6616, the main shaft 4706 includes a retaining nut 4722 adapted to engage to provide axial support and positioning for the bearing 4718. Thus, the bearing 4718 is axially captured between the retaining nut 4722 and the shoulder provided by the seal mount 6614. The main shaft 4706 can also include bearing race guide surfaces 6626, 6628 for supporting a bearing race 4914 (see fig. 49A and corresponding text). In certain embodiments, as shown in fig. 66B, the diameter of guide surface 6628 is less than the diameter of guide surface 6626. In certain embodiments, the primary shaft 4706 may have a reduced diameter portion 6630 compared to the guide surface 6628 for improved ease of assembly.

Still referring to fig. 47 and 66A-66D, in certain embodiments, one end of the main shaft 4706 is provided with a threaded surface 6620 adapted to receive a taper nut 4724, the taper nut 4724 generally serving to secure the main shaft 4706 to a dropout, a mounting bracket, a bracket element, or other vehicle frame element supporting the CVT 4700. The flats 6602, 6604 are adapted to receive and support an anti-rotation washer 6515 (see fig. 65A) and an anti-rotation washer 4726 (see fig. 47A), respectively. The anti-rotation washers 6515, 4726 are adapted to assist in the reaction of torque from the main shaft 4706 to a frame member (e.g., a bicycle dropout or other mounting member) of the vehicle support CVT 4700. In one embodiment, the main shaft 4706 may have a threaded surface 6632 for engaging a shift rod retainer nut 6502 and a jam nut 4926. Among other things, lock nut 4926 is adapted to ensure axial support and positioning of bearing nut 4912.

For some applications, such as for bicycles or similar sized applications, the main shaft 4706 may be approximately 175 and 815mm long. The central bore 6622 is about 5.5 to 7.5mm in diameter. In certain embodiments, the depth of the central bore 6624 is about 2.5-3.5 mm. For some applications, the length of the slot 6606 is approximately 25-45mm, which depends in part on the variator ratio of the CVT 4700. The width of the slot 6606 can be, for example, 7-11 mm. In one embodiment, the main shaft 4706 is made from a single piece of material, such as AISI4130, an alloy steel pre-hardened to RC 35-40. Of course, other materials may be used, such as magnesium, aluminum, titanium, composites, thermoplastics, thermosets, or other types of materials, depending on the application.

Fig. 67A-67E illustrate one embodiment of an input driver 4904. The input drive 4904 is a generally cylindrical hollow housing having a flange 6702 at one end and a splined surface 6704 at the other end. Referring again to fig. 94A, the input drive 4904 also includes bearing races 6706, 6708 for bearing against ball bearings 4910A, 4910B. The input driver 4904 includes a slot 6710 for receiving a retaining clamp that helps secure the flywheel 4902. The input drive 4904 may also have a surface 6714 for supporting the bearing 4916 against which the hub shell 4702 rests on the bearing 4916. Input drive flange 6702 abuts a torsion disc 4906, which torsion disc 4906 is mounted on a torsion disc seat 6716 of input drive 6904. In another embodiment, input drive 4904 and twist disk 4906 are a single integral piece. In some embodiments, input drive 4904 and torsion disk 4906 are connected by splines, keyways, or other connection means suitable for transmitting torque.

For some applications input driver 6904 may have an outer diameter of about 25-88mm and an inner diameter of about 24-27mm at the thinnest portion. The bearing races 6704, 6706 may be about 5-7mm in diameter. For some applications, the overall length of input driver 6904 may be approximately 34-36 mm. For example, the input drive 6904 may be made from alloy steel SAE 8620, which may be heat treated to a depth of HRC 58-62 to about 0.8 mm. In certain embodiments, input driver 6904 is made of a magnesium alloy, an aluminum alloy, a titanium alloy, or other lightweight material.

One embodiment of twist disk 4906 is now described with reference to fig. 68A-68B. Twist disk 4906 may generally be a disk having an outer diameter with a plurality of splines 6806, said splines 6802 being adapted to engage with cooperating splined surfaces of cam driver 4908. In the embodiment of twist disk 4906 shown, there are five splines 6802; however, in other embodiments, the number of splines may be any number, such as from 1 to 10, or more. Also, although splines 6802 are shown as round, in other embodiments splines 6802 are square or any other shape capable of performing this function. Twist disk 4906 also has a central bore 6804 adapted to receive input drive 4904. In certain embodiments, the central bore 6804 mounts splines that engage cooperating splines of the input drive 4904. In certain embodiments, such as the embodiment shown in fig. 68A-68B, it may be preferable to provide a cut-out 6806 for reducing the weight of twist disk 4906. The number, shape, and location of the cuts may be varied in any manner as long as the structural integrity of twist disk 4906 is suitable for the specific operating conditions of all given applications. In some applications, the central bore 6904 is about 28-32mm in diameter. In some embodiments, the outer diameter of twist disk 4906, excluding splines 6806, is about 60-66 mm. In a first draft example, the thickness of the twisting disk is about 1.5-3.5 mm. Fig. 69A-69C generally illustrate an input subassembly including a twist disk 4906 and an input drive 4904.

Referring now to fig. 70A-70C, one embodiment of the cam driver 4908 is now described. Cam driver 4908 is generally an annular disc having a central bore 7002, the center 7002 having female splines 7004 adapted to mate with splines 6802 of twist disk 4906. In some embodiments, cam driver 4908 is provided with male splines and twist disk 4906 is provided with cooperating female splines. Cam driver 4908 further includes a load cam roller reaction surface 7006 adapted to react axial loads transmitted through load cam roller 6404 (see fig. 50B). Reaction surface 7006 is generally a planar ring on the periphery of cam driver 4908. It should be noted that in other embodiments, the reaction surface 7006 may not be planar, but may have other shapes, including a bevel similar in shape, size, and number to the bevel 6202 of the traction ring 6200. In certain embodiments, as shown in fig. 70C, cam driver 4908 may be provided with a reinforced circular rib 7008 around central bore 7002. In the illustrated embodiment, the cam driver 4908 is also provided with a shoulder 7010 for supporting the bearing.

In one embodiment, cam driver 4908 has an outer diameter of about 105 and 114mm and the surface not including female splines 7004 has an inner diameter of about 63-67 mm. For example, the width of the reaction surface 7006 may be about 6-8 mm. In some embodiments, the primary thickness of the cam driver 4908 is about 7-9 mm. For some applications, the cam driver 4908 is made of, for example, alloy steel AISI52100 or a titanium alloy or other lightweight alloy or material.

Referring now to fig. 71A-71C, one embodiment of the flywheel 4902 is now described. Flywheel 4902 is a one-way clutch that transfers torque from a chain (not shown) in a first direction but not in a second direction because there is a set of pawls that rest on a set of ratchet teeth in the second direction (not shown since flywheel function is well known in mechanical designs and there are many means to accomplish this function). Elements of the flywheel that are not known are described herein. The flywheel 4902 has a splined inner bore 7102 adapted to cooperate with splines 6704 of the input drive 4904. In certain embodiments, the flywheel 4902 has a set of teeth 7104 offset from the center of the body 7106 of the flywheel 4902. The number of teeth 7104 can be any number from 8 to 32, preferably including 16, 17, 18, 19, 20, and 21. In certain embodiments, for example, the flywheel 4902 may be made of alloy steels SAE 4130, 4140. In one embodiment, the splined inner bore 7102 may have an outer diameter of about 27-32mm (splines not considered) and about 29-34mm (including splines). For some applications, the body 7106 of the flywheel 4902 may have a width of about 14-17mm, with the teeth 7104 about 1.0-6.0mm from the center, or preferably 1.5-4.5mm in some applications.

Referring now to fig. 72A-72C, one embodiment of the hub shell 4702 will now be described. The hub shell 4702 includes a generally cylindrical hollow shell 7202 having a flange 7204, which in one embodiment, the flange 7204 has a hole 7206 adapted to receive a bicycle wheel spoke. In other embodiments, for applications that use pulleys or drive belt output, the flange 7204 is replaced by a bushing for the pulley. One end of the housing 7202 has a bore 7208 that is generally adapted to cooperate with or receive the hubcap 4704 (see fig. 47) to form a housing for the various components of the CVT 4700. The housing cover 4704 can be secured to the hub shell 4702 by any suitable means, such as bolts, threads, or snap rings. As best shown in fig. 72C, the hub shell 4702 can have a snap ring groove 7216 for receiving a snap ring 5110 (see fig. 51 showing a dual ring snap ring or retainer ring 5110), the snap ring 5110 assisting in securing the hub shell cover 4704 to the hub shell 4702. In one embodiment, the hub shell 4702 has a cover engagement surface 7218 adapted to receive and cooperate with a hub shell cover (e.g., the hub shell cover 4704 or other hub shell covers described herein). The hub shell 4702 of certain embodiments has a shoulder 7220 adapted to provide a positive stop for the hub shell cover 4704.

The other end of hub housing 7202 includes an integral base or cover 7210 having a central bore 7212 adapted to receive an input drive 4904. In certain embodiments, as shown in fig. 49A, the central bore 7212 is adapted to receive and be supported by a radial bearing 4916. Thus, the central bore 7212 may have a groove 7226 for receiving a radial bearing 4916. The central bore 7212 may also include a groove 7228 for receiving a retaining clip that retains the radial bearing 4916 within the groove 7226. In certain embodiments, the central bore 7212 can have a groove 7230 for receiving a seal 4918. In one embodiment, cap 7210 is provided with a shoulder or seat 7224 for receiving a thrust washer 4922 (see fig. 50A). In other embodiments, the cap 7210 is not integral with the housing 7202 and is secured to the housing 7202 by, for example, threads, bolts, or other fastening means. As shown in fig. 72A, in certain embodiments, the hub shell 4702 includes reinforcing ribs 7214 around the periphery of one or both flanges 7204. Similarly, as shown in fig. 72B, the hub shell 4702 can include an integral circular rib 7222 that reinforces an integral bottom cap 7210. In some implementations, circular ribs 7222 reinforce the joints where housing 7202 is coupled to bottom cap 7210. Where bottom cap 7210 is not integral with hub shell 7202, circular ribs 7222 can be in the form of separate ribs, similar to ribs 7214, that reinforce the internal junction between hub shell 7202 and bottom cap 7210.

For some applications, the inner diameter of the housing 7202 is about 114mm and 118mm, and the thickness of the housing is about 3-5 mm. In one embodiment, for example, depending on the bearing 4916 and seal 4918 (see FIG. 49A), the central bore 7212 is about 36-43mm long. In some embodiments, the distance between the flanges 7204 is about 48-52 mm. In certain embodiments, for example, the hub shell 4702 may be made of cast aluminum a380, but in other embodiments the hub shell is made of a titanium alloy, a magnesium alloy, or other lightweight material.

Fig. 73 illustrates an embodiment of a hub shell 7302 that is similar to the hub shell 4702. The hub shell 7302 includes a set of coarse splines 7304 around the bore 7208. Splines 7304 are adapted to mate with a corresponding set of splines of a hub shell cover (e.g., hub shell cover 4704). Fig. 74 illustrates another embodiment of a hub shell 7402 that is similar to the hub shell 4702. The hub shell 7402 includes a knurled surface 7404 around the bore 7208. In certain embodiments, the knurled surface 7404 is adapted to engage a corresponding knurled surface of the hub housing cover; in another embodiment, the knurled surface 7404 is adapted to cut into the material of the hub shell cover to form a rigid connection.

Referring to fig. 75A-75G, one embodiment of a hubcap 7500 is shown. The hub shell cover 7500 generally serves the same function as the hub shell cover 7404 shown in fig. 47, i.e., cooperates with the hub shell 4702 to form a housing for the components of the CVT 4700. The hubcap 7500 is a generally circular disk having a central aperture 7502, said central aperture 7502 being adapted to receive and be supported by the radial bearing 4718 (see fig. 47). Wherein a splined extension or flange 7504 extending from the central aperture 7502 is adapted to receive a corresponding cooperating portion for providing a braking function or a cover function. For example, one such corresponding cooperating part may be a mechanism known in the industry as a roller brake. In certain embodiments, the spline extension includes a groove adapted to receive bearing 4718.

In the illustrated embodiment, the hub shell cover 7500 includes a knurled outer periphery or surface 4702 adapted for self-pulling pins on a hub shell (e.g., hub shell 4702). In certain embodiments, the knurled surface 7506 is comprised of straight knurls. In certain embodiments, the knurled surface 7506 is machined such that when the hub shell cover 7500 is pressed onto the hub shell 4702, the knurled surface 7506 cuts into the hub shell 4702 such that the hub shell cover 750 becomes firmly pressed or embedded into the hub shell 4702, and vice versa. As the knurled surface 7506 cuts into the hub shell 4702, the shredded material loosens. Thus, in certain embodiments, the hubcap 7500 includes a recess 7510 for receiving shredded material. In one embodiment, groove 7510 is formed to facilitate knurled surface 7506 having an angular, sharp profile, or sharp teeth at an edge of knurled surface 7506 proximate groove 7510.

As best shown in fig. 75E, 75G, in certain embodiments the hub shell cover 7500 has a guide step 7514 that facilitates guiding the hub shell cover 7500 into the hub shell 4702 prior to engagement of the knurled surface 7506 with the hub shell 4702. In the illustrated embodiment, the hub shell cover 7500 is provided with a groove 7512 for receiving an O-ring 5105, which O-ring 5105 acts as a seal between the hub shell cover 7500 and the hub shell 4702. In certain embodiments, the hub shell cover 7500 is provided with an aperture 7508 that supplies or drains lubricant to or from the housing formed by the hub shell 4702 and the hub shell cover 7500.

In one embodiment, the central aperture 7502 is about 26-29mm in diameter, which varies depending on the configuration of the bearing 4718 and seal 4720 (see FIG. 47). The hub cap 7500 includes a surface having an outer diameter of about 118 and 122 mm. In some embodiments, the splined extension 7504 has an outer diameter of about 34-37 mm. It should be understood, however, that the outer diameter of the spline extensions can be sized and numbered and configured in any manner consistent with the characteristics of any commercial or commercial brake mechanism. For example, in certain embodiments, the hub shell cover 7500 can be made of a wrought steel alloy, SAE 1045, but in other embodiments, is made of an aluminum alloy, a titanium alloy, a magnesium alloy, or any other suitable material.

Referring now to fig. 76A-76F, another embodiment of a hub shell cover 7600 is shown as a hub shell cover that shares many of the similar features as hub shell cover 7500. The hub shell cover 7600 includes a disc brake fastening extension 7602 having a bolt hole 7604 for receiving a bolt that secures the disc brake to the fastening extension 7602. In this embodiment, the fastening extension 7602 is integral with the rest of the body of the hub cap 7600; however, in other embodiments, the fastening extension 7602 is another separate part adapted to be secured to the main disc of the hubcap 7600. The number, size and location of the bolt holes 7604 will vary depending on the characteristics of any given disc brake mechanism. It should be understood that while the illustrated embodiment of the hubcaps 7500, 7600 are provided with extensions 7504, 7602 for mating with the detent mechanism, in other embodiments, the extensions 7504, 7602 may not be integral with the hubcaps 7500, 7600; rather, the hubcaps 7500, 7600 can be configured with features for receiving a brake mechanism, which itself has extensions 7504, 7602.

In certain embodiments of the hub shell 4702 and the hub shell cover 4704, either or both of the hub shell 4702 and the hub shell cover 4704 can be fitted with torque transmission features for outputting torque from the CVT 4700. For example, a sprocket (not shown) may be secured to the hub shell cover 4704 so that torque may be transmitted to the driven device via a chain. As another example, in addition to or in lieu of flange 7204, a sprocket (not shown) can be connected to the hub shell 4702 for transmitting output torque from the CVT4700 via, for example, a chain.

Referring to fig. 47, 49, 52, and 67, one manner of operation of the CVT4700 will now be described. Power is input to the CVT4700 through the flywheel 4902 at a certain torque Ti and rotation speed Ni. An input driver 4904 splined to flywheel 4902 transfers power to a torsion disc 4906, which torsion disc 4906 transfers power to a load cam driver 4908. The cam rollers 6404, actuated by the load cam driver, ride up the ramp 6202 of the input traction ring 4810 and create a torque transfer path between the load cam driver 4908 and the input traction ring 4810. The cam rollers 6404 convert the tangential or rotational force of the torsion disk 4906 into an axial clamping component and a tangential or rotational component, both of which are transmitted through the power rollers 6404 to the input traction ring 4810. The input traction ring 4810 transmits power to the power rollers 4802 at approximately Ni rotational speed through frictional or traction contact.

Referring again to fig. 49, when the power roller shafts 4826 are parallel to the main shaft 4706, the contact points between the power rollers 4802 and the output traction ring 4812 cause the power rollers 4802 to transmit power to the output traction ring 4812 at substantially the same speed No as Ni. When the power roller shaft 4826 is tilted closer to the output side of the main shaft 4706 (as shown in fig. 47), the contact point between the power rollers 4802 and the output traction ring 4812 causes the power rollers 4802 to transmit power to the output traction ring 4812 at a speed No greater than Ni. This situation is sometimes referred to as overspeed. When the power roller shaft 4825 is tilted closer to the input side of the main shaft 4706 (not shown), the contact point between the power rollers 4802 and the output traction ring 4812 causes the power rollers to transfer power to the output traction ring 4812 at a speed No less than Ni. This situation is sometimes referred to as low speed travel.

An output traction ring 4812 having a ramp 6203 similar to (but not necessarily identical to) ramp 6202 of output traction ring 4810 actuates load cam rollers 6405 such that load cam rollers 6405 provide a path for power to be transmitted between output traction ring 4812 and hub shell cover 4704. Because the hub shell cover 4704 is fixed to the hub shell 4702 in the rotational direction, the hub shell cover 4704 transmits power to the hub shell 4702 at speed No. As previously mentioned, the hub shell 4702 is in this case adapted to receive a bicycle spoke (spokes and wheel not shown) for driving a bicycle wheel. Thus, power is transmitted from the hub shell 4702 to the bicycle wheel through the bicycle spokes. In other embodiments of the CVT4700, power is transmitted to other forms of output devices, such as pulleys, sprockets, or other forms of power transmission devices.

To manage and/or minimize slip or creep at the contact points between the input traction ring 4810, the idler 4814, and the output traction ring 4812, the input AFG 4712 and the output AFG4714 are used. To reduce reaction time and ensure sufficient contact force at low torque inputs, torsion springs 5002, 5003 act on the input traction ring 4810 and roller cage, and output traction ring 4812 and roller cage 5005, respectively, to provide a certain amount of axial or clamping force (also referred to as "preload") of the input traction ring 4810 and output traction ring 4812 against the power rollers 4802. It should be noted that in some embodiments, only one of the input side or the output side of the CVT4700 is provided with the preload mechanism.

As already described with reference to fig. 50A-50B and 51, during operation of the CVT4700, axial forces are generated by the interaction between the input and output traction rings 4810, 4812, rollers 6404, 6405 and the load cam driver 4908 and the hubcap 4704, respectively. The magnitude of the generated axial force is approximately proportional to the torque through the input and output traction rings 4810, 4812.

Referring now specifically to fig. 47, 48 and 61, the execution of the adjustment of the gear ratio of the CVT4700 will now be described. A shift mechanism (not shown), such as a pulley and cable system, is coupled to the splined end 6104 of the shift lever 4816 to cause rotation of the shift lever 4816. Because the shift rod 4816 is axially restrained by the main shaft 4706 and the shift rod holder nut 6502, the shift rod 4816 rotates in position about its own longitudinal axis. This rotation of the shift rod 4816 causes the shift rod nut 4818 to translate axially along the threaded end 6102 of the shift rod 4816.

When the shift rod nut 4818 is axially moved, the shift rod nut 4818 axially drives an idler bushing 4832 connected to the shift cam 4820. Axial translation of the shift cam 4820 causes the shift cam rollers 4822 to roll along the profile of the shift cam 4820, thereby driving the legs 4824 to move such that the roller shafts 4826 are tilted. As described above, the relative inclination between roller shaft 4826 and main shaft 4726 determines the relative difference between input speed Ni and output speed No.

Referring now to fig. 77-82D, various embodiments of idler subassemblies are described. Referring to fig. 77, in one embodiment, the idler and shift cam assembly 7700 includes an inner bushing 7705 adapted to be mounted on a shaft 7710. The inner bushing may have a bore 7715 that receives a shift rod nut 7720 threaded on the shift rod 7725. The inner liner 7705 is generally cylindrical with an inner bore and an outer diameter. A roller bearing assembly 7730 is mounted on the inner liner 7705. Idler pulley 7735 rests on roller bearing assembly 7730. The shift cams 7740 are radially positioned by the inner liner 7705. For example, the idler and shift cam assembly 7700 can include one or more clips to hold the components together. Although shaft 7710, shift rod nut 7720, and shift rod 7725 are shown in fig. 7, these components need not be part of the idler and shift cam assembly 7700.

In certain implementations, the outer diameter surface of the inner liner 7705 can provide a bearing race for the bearing assembly 7730, as described further below. The inner diameter surface of the idler 7735 may provide a bearing race for the bearing assembly 7730. In certain embodiments, one or both shift cams 7730 may be configured integral with the inner liner 7705. In other embodiments, one or both shift cams 7730 can provide the bearing races of bearing race 7730. In other embodiments, the idler 7735 has one or more features that transfer thrust loads to the bearing assembly 7730.

Referring now to fig. 78, in operation, the power rollers 7802 apply axial and radial loads to the idler pulley 7735. When shift rod 7725 and shift rod nut 7720 actuate shift cams 7740 through inner bushing 7705, the legs 7806, which are typically connected to power rollers 7802 through shaft 7804, react the axial thrust load of the idler and shift cam assembly 7700. In some embodiments, it is preferred that the idler 7735 rotate freely about the axle 7710 as the power roller 7802 rotates about the axle 7804. The roller bearing assembly 7730 allows free rotation of the idler pulley 7735, eliminating frictional losses that would otherwise occur between the idler pulley 7735 and the inner liner 7705. In addition, the idler bearing assembly 7730 must be able to handle the axial and radial loads that occur during operation of the idler and shift cam assembly 7700. In certain embodiments, the idler pulley 7735 and/or the roller bearing assembly 7730 are adapted to transfer thrust loads from the idler pulley 7735 to the roller bearing assembly 7730.

In certain embodiments, for example, in a bicycle application or similar torque application, the idler 7735 is configured to withstand a compressive load of about 5GPa to about 50GPa, made of, for example, steel. In certain embodiments, the idler 7735 is configured to rotate on the roller bearing assembly 7730 at a rotational speed of 2 revolutions per minute (rpm) to 400rpm, 1rpm to 20000rpm, or 60rpm to 360rpm, or 100rpm to 300 rpm. In certain embodiments, the idler pulley 7735 and roller bearing assembly 7730 are preferably configured to provide the ability to react an axial thrust of about 350 pounds.

In some embodiments, the shift cams 7740 are manufactured to have a hardness of about RC 55 and may be made of a suitable material, such as steel, titanium, aluminum, magnesium, or other materials. In certain embodiments, the inner liner 7705 may be made of a metallic material, such as steel, and preferably, the inner liner 7705 has a hardness of about RC 20 or greater.

Roller bearing assembly 7730 may include one or more needle bearings, radial ball bearings, angular contact bearings, tapered bearings, spherical rollers, cylindrical rollers, or the like. In certain embodiments, the roller bearing assembly 7730 includes rolling elements configured to roll on races that are integral with one or more of the idler 7735, the shift cam 7740, or the inner liner 7705. In other embodiments, the roller bearing assembly 7730 includes roller elements, cages for the roller elements, and races; in these embodiments, the roller bearing assembly 7730 may be press fit (or interference fit) between, for example, the idler 7735 and the bushing 7705. In certain embodiments, a clearance fit may be used for machining purposes.

Referring now to fig. 79A-79D, an idler and shift cam assembly 7900 includes an inner sleeve 7905, the inner sleeve 7905 having a generally cylindrical body and having a cut-out hole 7907 in about a middle portion of the cylindrical body, the hole 7907 being generally perpendicular to a major axis of the cylindrical body. The bore 7907 is adapted to receive a shift rod nut, as described above. In this embodiment, the inner sleeve 7905 includes a slot 7909 for receiving the retaining clip 7910.

Two corner face contact bearings 7912 are mounted on the inner sleeve 7905; for example, the bearing 7912 may be slidably mounted on the inner sleeve 7905. In this embodiment, bearing 7912 may be a typical bearing having roller elements 7916, an inner race 7918, and an outer race 320. Idler 7914 may be coupled to outer race 320 of bearing 7912, such as by an interference fit. As shown in fig. 79C, the idler 7914 in this embodiment has a thrust transfer feature 7922 (top thrust wall 7922) that transfers thrust between the idler 7914 and the bearing 7912.

An idler pulley 7914 is provided with shift cams 7924 on each side. Shift cams 7924 have cam profiles 7926, which cam profiles 7926 are configured to operatively connect to ball leg assembly 48320 (see fig. 48A), such as leg 7706 shown in fig. 78. In this rudimentary example, shift cam 7924 is allowed to rotate about a longitudinal axis of idler and shift cam assembly 7900. Additionally, in this embodiment, inner sleeve 7905 provides a shoulder 7928 that receives a bore of shift cam 7924.

Referring to fig. 80A-80D, another version of an idler and shift cam assembly 8000 includes an inner bushing 8005, the inner bushing 8005 having a generally cylindrical body and a cut-out bore 8007 at about a mid-portion of its cylindrical body, the bore 8007 being generally perpendicular to a major axis of the cylindrical body. The bore 8007 may have any shape suitable for receiving a shift rod nut of a continuously variable transmission shift mechanism. For example, the shape of the aperture 8007 may be circular, square, oval, irregular, etc. Inner sleeve 8005 includes a slot 8009 that receives retaining clip 8010.

In the embodiment shown in fig. 80A-80D, shift cam 8024 is configured to provide a race 8018 to roller element 8016. The roller elements in this case are spherical ball bearings. In some applications, the ball bearings have a diameter of about 0.188 inches. However, in other embodiments, the ball bearings may be any size suitable to handle the static and dynamic loads applied to the idler and shift cam assembly 8000. Additionally, the number of ball bearings is selected to meet the performance requirements of the idler and shift cam assembly 8000. The idler wheel 8014 is configured with portions that provide a race 8020 for the roller element 8016. The idler pulley 8014 additionally has a pusher wall 8022 for transmitting thrust to the roller element 8016. In certain embodiments, such as the embodiment shown in fig. 80A-80D, a roller element spacer 8028 can be provided to prevent the roller elements 8016 from contacting each other in a manner that compromises the performance of the idler and shift cam assembly 8000.

The shift cam 8204 provides a shoulder 8032 for receiving a retaining ring 8030, which retaining ring 8030 facilitates assembly of the idler and shift cam assembly 8000 by providing a means such as a retaining shift rod nut 7720. In this embodiment, shift cam 8024 is also configured with a lock-out key 8034, which lock-out key 8034 engages shift rod nut 7720, preventing it from rotating about the longitudinal axis of idler and shift cam assembly 8000.

Fig. 81A-81D illustrate another embodiment of an idler and shift cam assembly 8100. The inner liner 8105 includes a through bore 8107 that is generally perpendicular to the major axis of the cylindrical body of the inner liner 8105. As in other embodiments, the shape of through bore 8107 may be any shape suitable for receiving, for example, a shift rod nut 7720. The inner liner 8105 also includes a slot 8109 that receives the retention clip 8110. In this embodiment, a thrust washer 8130 is mounted between the retention clip 8110 and the shift cam 8124, the shift cam 8124 being configured with a slot for receiving the thrust washer 8130. In some embodiments, shift cam 8124 also includes a slot 8132 for receiving a spring (not shown) that provides a preload.

Shift cam 8124 of idler and shift cam assembly 8100 has a profile that provides shift rod nut 7720 with an internal bore portion of lock key 8134. The shift cam 8124 provides a race 8118 for the roller element 8116. In some instances, roller element spacers 8128 are provided to keep roller elements 8116 spaced apart. Idler 8114 has a thrust wall 8122 and a portion that provides a race 8120 for roller element 8116.

Referring now to fig. 82A-82D, an alternative embodiment idler and shift cam assembly 8200 is illustrated. The idler 8214 is configured with a portion that provides a race 8220 for the roller element 8216. The idler 8214 also includes a pusher wall 8222. Roller spacers 8228 prevent the rollers 8216 from contacting each other during operation of the idler and shift cam assemblies 8200.

The shift cam 8225 has a cam profile 8227 and a portion that provides a race 8218 for the roller element 8216. The shift cam 8225 includes an inner bore having a through bore 8207, which through bore 8207 is generally perpendicular to the cylindrical body of the shift cam 8225. The through bore 8207 is adapted to receive, for example, a rod nut 7720. The shift cam 8225 may also include an inner bore for receiving the shift cam 8224.

The shift cam 8224 has a cam profile 8227 that is similar to the profile of shift cam 8225. The inner bore of the shift cam 8224 is mounted on the outer diameter portion of the shift cam 8225. A retaining clip 8210 received within a slot 8209 of the shift cam 8225 retains the shift cam 8224 in place on the shift cam 8225. Shift cams 8224 and 8225 collectively receive shift rod nut 7720. In this embodiment, a retaining ring 8230 is provided to facilitate assembly of idler and shift cam assembly 8200 to shift rod nut 7720 and shift rod 7725. The positioning ring is partially mounted on the outer diameter of the shift cam 8224 and between the shift cams 8224, 8225 and the idler 8214.

In certain embodiments, the length of the inner liner 7705 (see fig. 77) is controlled, for example, to the center cutout 7715 of the shift rod nut 7720. The length of the portion of the inner liner 7705 extending from the slit 107 may vary. In some embodiments, the ends of the bushings 7705 bear against fixed surfaces that determine the shift travel limits that control the maximum and minimum gear ratios of the CVT

Referring now to FIGS. 83A-83D, the quick release Shifter (SQR) mechanism 8300 is now described. In certain embodiments, the SQR mechanism 8300 includes a back plate 8302 connected to the indexing disk 8304. The back plate 8302 is adapted to receive a retaining ring 8306 and a release key 8308. The CVT shaft 8310 is provided with a groove 8312, as for receiving the retaining ring 8306.

A back plate 8302, indexing plate 8304, and positioning ring 8306 are coaxially mounted about the shaft 8310. A shifter mechanism (not shown) is connected to the back plate 8302 ensuring that the release key 8308 is held between the back plate 8302 and a portion of the shifter mechanism (e.g., the housing). The SQR mechanism 8300 is held in place axially by a retaining ring 8306 in the groove 8312 and certain components of the shifter mechanism housing (not shown).

The retaining ring 8306 includes a generally circular ring 8314 having a hole from which a retaining ring extension 8316 extends outwardly forming a V-shape. The release key 8308 has a v-shaped end that is substantially adapted to actuate the deployment of the retaining ring extension 8316 when inserted into the v-shaped aperture formed by the retaining ring extension 8316. The release key 8318 may also be provided with a positioning extension 8320 that facilitates support and guidance of the release key 8308 when the positioning extension 8320 is installed in the back plate 8302.

The indexing plate 8304 is a generally flat plate having a central aperture 8322 with a flat surface 8324 adapted to fit over the flat surface 8234 of the shaft 8316. The indexing disk 8304 additionally may have a plurality of indexing slots 8326. In some embodiments, the back plate 8302 includes a retaining ring groove 8328 adapted to receive the v-shaped end 8318 of the retaining ring extension 8316 and the release key 8308. The back plate 8302 may also have a release key slot 8330 adapted to receive a locating extension 8320 of the release key 8308. The back plate 8302 additionally has a central bore 8332, the central bore 8332 having a beveled edge 8334 adapted to push the retaining ring 8310 into the groove 8312 when the SQR mechanism 8300 is pulled toward the shaft end 8336 of the shaft 8310. In certain embodiments, the back plate 8302 includes a slot 8338 adapted to receive the indexing disk 8304. The diameter of the slot 8338 may be selected such that the outer diameter of the indexing disk 8304 serves as a guide and/or support surface for the back plate 8302.

By depressing the release key 8308, the retaining ring 8306 is opened, allowing the SQR mechanism to slide over the shaft 8310, thereby securing the SQR mechanism 8300 to the shifter mechanism and to the shaft 8310. A back plate 8302 secured to the shifter mechanism using, for example, bolt holes 8342, can be angularly positioned relative to the indexing plate 8304 to provide a desired position of the shifter housing for receiving, for example, a shift cord or shift wire. The back plate 8302 is then secured to the index plate by bolts (not shown) that fit through the bolt holes 8340 of the back plate 8303 and the index plate slots 8326.

When the SQR mechanism 8300 is pulled toward the shaft end 8336, the beveled edge of the back plate 8302 wedges against the retaining ring 8306 to prevent the SQR mechanism 8300 from disengaging from the shaft 8310. However, when the v-shaped end 8318 of the release key 8308 presses against the ring extension 8316, the retaining ring 8306 expands to fill the groove 8312. The SQR mechanism 8300 can then be pulled off the shaft 8310 along with the shifter mechanism fixed to the SQR mechanism 8300. Thus, among other things, the one-time-mount SQR mechanism allows the shifter mechanism to be disassembled by simply actuating the release key 8308.

Referring now to fig. 84A-84E, the shifter interface mechanism 8400 includes a pulley 8402 mounted on a shaft 8404 adapted to receive a shift lever 8406. A shift rod nut 8408 is threaded onto the shift rod 8406 and is connected to the pulley 8402 by a dowel pin (not shown). A back plate 8410 is mounted on the shaft 8404 and is connected to the pulley 8402. A retaining clip 8412 is located in a groove (but not labeled) in the shaft 8404.

The pulley 8402 may have a plurality of grooves 8414, such as wires, for receiving and guiding a shifter mechanism (not shown). The pulley 8402 may include a groove 8416 for receiving a shift rod nut 8404. In certain embodiments, the groove 8418 of the pulley 8402 is adapted to receive the back plate 8410. In one embodiment, the pulley 8402 includes a plurality of bolt holes 8420 for receiving bolts (not shown) that secure the pulley 8402 to the back plate 8410. In the illustrated embodiment, pulley 8402 has a groove 8422 for receiving a dowel pin (not shown) that couples pulley 8402 to shift rod nut 8408. In certain embodiments, the pulley 8402 also includes a plurality of bolt holes 8424 for retaining a shift rod nut 8408 in the axial direction within a groove 8416 of the pulley 8402. In some embodiments, the pulley 8402 includes a shift wire channel 8426 through which a shift wire (not shown) extends from the pulley groove 8414 to the groove 8415, facilitating clamping of the shift wire or shift cord in the pulley 8402.

With particular reference to fig. 84D, the back plate 8410 is a generally circular flat plate having a central hole 8428 for mounting the back plate 8410 about an axis 8404. In certain embodiments, the back plate 8410 has a plurality of bolt holes 8430 that facilitate securing the back plate 8410 to the pulley 8402. As shown in fig. 84E, a shift rod nut 8408 is generally circular in shape, adapted to fit within a groove 8416 of the pulley 8402. A shift rod nut 8408 has a threaded central bore 8432 for threading on a shift rod 8406. In one embodiment, shift rod nut 8408 includes a notch 8434 for receiving a locating pin (not shown) that rotationally fixes shift rod nut 8408 to pulley 8402. In certain embodiments, a shift rod nut 8408 is defined in the axial direction by the shaft 8404 and/or the pulley 8402 and the head of a bolt that is installed in a bolt hole 8424 of the pulley 8402.

During operation of the shifter interface 8400, the pulley 8402 rotates in a first angular direction about the shaft 8404. Since the shift rod axis 8408 is rotationally fixed to the pulley 8402 and axially defined by the shaft 8404 and the shifter housing, the shift rod nut 8408 causes the shift rod 8406 to translate in a first axial direction. Rotation of the pulley 8402 in the second angular direction causes the shift rod nut 8408 to actuate the shift rod 8406 to translate in the second axial direction. The back plate 8410 and the retaining clip 8412 prevent the shifter interface subassembly 8400 from sliding off the shaft 8402. The interaction between the pulley 8402 and the retaining clip 8412 prevents the shifter interface subassembly 8400 from translating axially along the main portion of the shaft 8404.

Referring now to FIGS. 85A-85E, one embodiment of a power input assembly 8500 is described. The power input assembly 8500 includes an input driver 8502 adapted to be connected to torque transfer keys 8504. In certain embodiments, the input actuator 8502 is a generally tubular body having a set of splines 8506 at one end and an extension 8507, i.e., a torque transmitting extension 8508 at the other end of the tubular body. The torque transfer extension 8508 is generally semi-circular in shape, formed by a cutout on the periphery of the extension 8507. The torque transfer extension 8508 includes a torque surface 8510. The extension 8507 also includes a torque-transmitting key retaining surface 8512. In certain embodiments, input drive 8502 includes a flange 8514 adapted to connect to a twist disk. In certain embodiments, the input drive 8502 includes a retaining clip slot 8513 formed within the torque transmission extension 8508.

For some applications, the torque transfer keys 8504 are provided with torque transfer tabs 8516 adapted to engage the torque transfer surfaces 8510. In certain embodiments, the torque transfer keys 8504 include concentric surfaces 8518 that ensure concentricity between the input drivers 8502 and the torque transfer keys 8504. Generally, the concentric surface 8518 has a semi-circular profile selected to concentrically engage the torque extension 8508. In certain embodiments, the torque transfer keys 8504 may have a plurality of cutouts 8520 for machining purposes, due to the machining operations that form the torque transfer tabs 8516, and in some cases also for weight reduction. As best shown in fig. 85C, in one embodiment, the torque transfer keys 8504 include beveled edges 8522 adapted to facilitate mounting of a torque transfer device (e.g., a flywheel) to the torque transfer keys 8504. In certain embodiments, the torque transfer keys 8504 can also include threads, splines, or keyed surfaces 8524 for engaging corresponding cooperating torque transfer devices (e.g., ratchet, sprocket, freewheel or other such devices or structures).

For some applications, torque transfer keys 8504 are mounted on the input drive 8502 such that the concentric surface 8518 matches the outer diameter of the torque transfer extension 8505 and such that the torque transfer surface 8510 matches the torque transfer tabs 8516. The torque transfer keys 8504 can be retained on the input driver 8502 because the torque transfer tabs 8516 are captured between the torque transfer key retaining surfaces 8512 and a retaining clip (not shown) located in the retaining clip slot 8513. During operation, a torque transfer device (e.g., a sprocket, flywheel, or pulley) is used to rotate the torque transfer key 8504 and then transfer torque to the torque transfer extension 8505 of the input drive 8504 via the torque transfer tabs 8516. Torque is then transferred from the input drive 8504 through the splines to, for example, a twist disk.

The combination of torque transfer keys 8504 and torque transfer extensions 8508 reduces backlash during torque transfer and provides precise concentric positioning between the input drive 8502 and the torque transfer keys 8504. Additionally, in some instances, the torque transfer features (e.g., torque transfer extensions 8508 and torque transfer tabs 8516) may be machined by using only standard axis milling and turning, thereby eliminating the need for more complex machining equipment.

Another embodiment of a continuously variable transmission, including its components, subassemblies, and methods, is described with reference to FIGS. 86-148. Components or subassemblies identical to those previously described have the same reference numbers in fig. 86-148. Referring now specifically to fig. 86-87, CVT8700 includes a housing or hub shell 8702 that is adapted to be coupled to a hub shell cover 8704. In one embodiment, the hub shell cover 8704 can be provided with an oil hole 8714 and its appropriate oil hole plug 8716. As described further below, in certain embodiments, the hub shell 8702 and the hub shell cover 8704 can be adapted to be secured together by threads. In certain such embodiments, it is preferable to provide a locking function or device to prevent the hub shell cover 8704 from being released from the hub shell 8702 during normal operation of the CVT 8700. Thus, in the illustrated embodiment, the locking keys 8718 are adapted to mate with features of the hub shell cover 8704 and are secured to the hub shell 8702 by bolts or screws 8720. Additional description of the locking key 8718 and related features of the hub shell cover 8704 is provided below.

The hub shell 8702 and hub shell cover 8704 are supported by bearings 4916 and 4718, respectively. The input drive 8602 is coaxially mounted about the main shaft 4709 and supports the bearing 4916. Mast 4709 has the same features as mast 4706 described with reference to figures 66A-66D; however, the main shaft 4709 is adapted to support the bearing 4718 axially inward of the seal 4720 (see fig. 47 for comparison). The input driver 8602 is connected to a torsion disc 8604, which torsion disc 8604 is connected to a cam driver 4908. The traction ring 8706 is adapted to be coupled to the cam driver 4908 by a set of rollers 6404 housed within the roller retainer 5004. A plurality of power rollers 4802 contact the traction ring 8706 and the traction ring 8708. The input drive ring 8710 is connected to the traction ring 8708 by a set of rollers 6405 that are housed within the roller retainer 5005. Input drive ring 8710 is adapted to be connected to hub shell cover 8704. In some embodiments, one or more shims 8712 can be positioned between the input drive ring 8710 and the hub shell cover 8704 to facilitate handling of tolerance stack-ups and to ensure proper contact and positioning of certain components of the CVT.

Referring additionally to fig. 88, idler assembly 8802 is generally adapted to support power rollers 4802 and facilitate shifting of CVT8700, among other things. In one embodiment, the idler assembly 8802 includes an idler bushing 8804 mounted coaxially about the main shaft 4706. Idler bushing 8804 is adapted to receive and support shift cams 8806. The support member 8808 is mounted coaxially around the shift cams 8806 and is supported by bearing balls 8810 for rolling on bearing races 8812 and 8814 formed on the support member 8808 and the shift cams 8806, respectively. In some embodiments, the idler bushing 8804 is adapted to receive a shift rod nut 8816 between the shift cams 8806, the shift rod nut 8816 being formed to receive the shift rod 4816. In this configuration of the idler shift assembly 8802, shift reaction forces generated during CVT shifting are transmitted directly through the shift cams 8806 to the shift rod nut 8816 and shift rod 4816, thereby substantially avoiding binding and drag caused by the transmission of shift reaction forces through the bearing ball 8810. The shift rod nut washer 4819 is supported coaxially with the shift cam 8806 and is supported by the shift cam 8806. The shift rod washer 4819 facilitates positioning of the shift nut 8816 to have a screw that threads the shift rod 4816 into the shift rod nut 8816.

The main shaft 4706 passes through the central bores of the hub shell 8702 and the hub shell cover 8704. The main shaft 4706 is adapted to support stator plates 4838, and in one embodiment, the stator plates 4838 are coupled together by stator rods 4840. One end of the shaft 4709 is adapted to receive a nut 4724 and an anti-rotation washer 4726. The shaft 4709 is also provided with an internal bore for receiving a shift rod 4816. A shift rod holder nut 6502 is coaxially mounted around the shift rod 4816 and is threaded on the main shaft 4709. Wherein the use of nut 4504 prevents the shift rod holder nut 6502 from loosening from the main shaft 4709. An anti-rotation washer 6515 may be located between the nut 6504 and a frame member, such as a fork end of a frame (not shown).

Referring now to fig. 89-93, the hub shell cover 8702 can include a set of threads 8802 adapted to engage a corresponding set of threads 9202 formed on the hub shell cover 8704. In certain embodiments, for applications such as bicycles, the hub shell 8702 includes flanges 8902, 8904 adapted to transfer torque to spokes such as bicycle wheels. As shown in fig. 90, in one embodiment, the flanges 8902, 8904 do not extend the same radial distance from the central bore of the hub shell 8702. In other embodiments, however, the hub shell 8703 can include flanges 8902, 8906 that extend to substantially the same radial length. To allow for the securement of the locking key 8718, the hub shell 8702 can be provided with one or more screw or bolt holes 8804.

Referring to fig. 92-93, more particularly, in one embodiment, the hub shell cap assembly 9200 can include a hub shell cap 8704, an oil hole plug 8716, a bearing 4718, a seal 9206, a locking ring 9208, and an O-ring 9210. As shown, the hub shell cover 8704 can have a central bore 9204 adapted to receive the bearing 4718, the seal 9206, and the locking ring 9208. With additional reference to fig. 94-98, the set of threads 9202 can be formed on an outer diameter or periphery of the hub shell cover 8704. In addition, the hub shell cover 8704 can include an O-ring groove 9602 on its outer diameter for receiving the O-ring 9210. In one embodiment, the central bore 9204 is provided with a seal groove 9702 and a lock groove 9704. The groove 9702 facilitates retention of the seal 9206 in the hub shell cover 8704. To prevent damage to seal 9206 and to improve its durability, seal groove 9702 may have a radius 9706. The locking groove 9704 is adapted to receive and retain a locking ring 9208, the locking ring 9208 helping to retain the bearing 4718 within the central bore 9204. In one embodiment, the hub shell cover 8704 can have an integral flange 9410, wherein the flange 9410 has a set of splines 9802 for providing a brake (e.g., bicycle roller brake (not shown)) adapter. With particular reference to FIG. 98, in one embodiment, the splines 9802 have a generally U-shaped profile that facilitates the machining of the splines; however, in other embodiments, the splines 9802 may be other shapes having square corners. In some embodiments, as shown more particularly in fig. 97, a groove or neck 9725 may be provided on the flange 9410 (or at the connection of the flange 9410 to the hub shell cover 8704) to facilitate engagement with, for example, a rib 9833 of the shroud 9832 (see fig. 114 and 115, and associated text).

Referring now to fig. 95, 96, 99 and 100, hub shell cover 8704 can be provided with a plurality of securing lugs or keys 9604 adapted to engage extensions 8750 of output drive ring 8710 (see also fig. 87). The keys 9604 serve as both an anti-rotation feature for the output drive ring 8710 and/or shims 8712 and as a securing feature for the output drive ring 8710 and/or shims 8712. In one embodiment, the hub shell cover 8704 includes a plurality of threaded holes 9808 adapted to receive bolts 9808 for securing a disc brake lining plate 9804 (see fig. 107). As shown in fig. 99, the holes 9502 are preferably blind to ensure that no leakage or contamination can occur through the holes 9502.

As previously described, in certain embodiments, the hub shell cover 8704 can include a locking feature or function that prevents the hub shell cover 8704 from being released from the hub shell 8702 during normal operation of the CVT 8700. In one embodiment, the thread locking function may be provided through the use of a locking engagement by threads, such as those sold by Loctite Corporation. For some applications, a suitable thread lock fit isLiquid Threadlocker 290^TM. In other embodiments, referring now to FIG. 101, the hub shell cover 8704 is provided with a plurality of locking teeth or grooves 9910 that are generally formed on the outer surface of the hub shell cover 8704 near the outer diameter. The locking grooves 9910 are adapted to mate with corresponding locking grooves 9912 (see fig. 102 and 103) of the locking key 8718. In one embodiment, the locking grooves 9910 are spaced about 10 degrees apart in a radial direction about the central bore 9204. However, in other implementations, the number and spacing of the locking slots 9910 may vary.

Referring now to fig. 102 and 103, the locking key 8718 includes a plurality of locking grooves 9912, the locking grooves 9912 having crests 9914 spaced apart by an angle α between lines passing through the center of the hub shell cover 8704. The angle alpha can be any angle; however, in one embodiment, the angle α is about 10 degrees. The locking key 8718 includes a generally oval shaped slot 9916. The foci of the oblong slot 9916 are angularly spaced by an angle β, which is preferably about half the angle α. A line forming the angle β extends from the center of the hubcap 9704. As shown in fig. 103, one focal point of the elliptical slot 9916 is radially aligned with the tooth top 9914 and the other focal point is radially aligned with the slot 9915 of the locking key 8718. When the locking key 8718 is flipped or inverted about a vertical axis (in the vertical plane of fig. 103), then the locking key 8718 has a configuration that mirrors its front face configuration. Thus, proper alignment of the locking groove 9912 with the locking groove 9910 is always achieved by a combination of movement of the groove 9916 on the bolt 8720 and/or flipping over of the locking key 8718. In other embodiments, the locking key 8718 may have a configuration in which the foci of the grooves 9916 are all angularly aligned with the tooth crests 9914, meaning that the locking key 8718 is no longer asymmetric about a vertical axis.

In one embodiment, the locking key 8718 spans an arc of about 28-32 degrees with a thickness of about 1.5-2.5 mm. For some applications, the locking key 8718 may be made of, for example, a steel alloy, such as 1010 CRS. As shown in fig. 104, the locking keys 8718 are fixed to the flange 8902 of the hub shell 8702 by bolts 8720. The detent grooves 9912 of the detent keys 8718 mate with the detent grooves 9910 of the hub shell cover 8704 to ensure that the hub shell cover 8704 remains threaded onto the hub shell 8702. Of course, in certain embodiments, a threaded locking fit may be used in conjunction with the trip device (e.g., the locking key 8718 and the hub shell cover 8704 with the locking slot 9910). In one embodiment, as shown in fig. 102A, a locking ring 8737 having a plurality of locking tabs 9912 and slots 9916 may be used in conjunction with a hubcap having locking tabs 9910.

Referring now to fig. 105 and 106, in an embodiment, among other things, hub shell cover 8704 can be provided with a cover 9920 adapted to provide a cover for flange 9410 and splines 9802. Additional description of the cover 9920 is now provided with reference to fig. 114 and 115, and the associated text. In other embodiments, the hub shell cover 8704 can be fitted with a disc brake assembly 9803, as shown in fig. 106. Referring to fig. 107-110, the disc brake assembly 9803 may include a retaining plate 9804 connected to a backing plate 9810. In one embodiment, as shown in fig. 107, the retaining plate 9804 and backing plate 9810 may be integral pieces, rather than separate portions. The retainer plate 9804 has one or more bolt holes 9806 for receiving bolts 9808 that facilitate connecting the retainer plate 9804 to the hub shell cover 8704. Bolts 9808 are received in bolt holes 9502 of hub shell cover 8704 (see, e.g., fig. 101). The backing plate 9810 includes a plurality of bolt holes 9850 for receiving bolts that secure the disc brake rotor to the backing plate 9810. The number of bolt holes 9850 may be adjusted to correspond with the number of bolt holes required for a standard or custom disc brake rotor. The disc brake kit 9803 may also include a boot 9812 adapted to mate with a cup washer 9814 to provide a dust and water tight seal at the interface between the backing plate 9810 and the spindle 4709. In some embodiments, the disc brake kit 9803 further includes a lock nut 9816, a bolt 9808, and an O-ring 9818. An O-ring 9818 is disposed between the retainer plate 9804 and the hub shell cover 8704 to provide a seal against, for example, water and other non-pressurized contaminants.

It should be noted that in some embodiments, the retaining plate 9804 is provided with a groove 9815 for receiving the flange 9410 of the hub housing cover 8704. However, in other embodiments, the hub shell cover 8704 does not include a flange 9410, and thus the recess 9815 is not used. In other embodiments, the hub shell cover 8704 integrally includes the retaining plate 9804 and the backing plate 9810. In one embodiment, the central bore 9817 of the backing plate 9810 includes a cup slot 9819 adapted to receive and secure the cup 9812.

Referring to fig. 111-113, in one embodiment, boot 9820 includes a plurality of retaining fingers or keys 9822 extending generally from an annular body having a dome-shaped outer portion 9824 and a tapered inner portion 9828. A recess 9830 between the dome-shaped portion 9824 and the cone-shaped portion 9828 is adapted to cooperate with, for example, a cup-shaped gasket 9814 to provide a labyrinth-type seal. In one embodiment, the tapered portion 9828 is inclined at an angle between about 8 degrees and 12 degrees from perpendicular to the cross-sectional plane shown in fig. 113. In some embodiments, the width of the boot 9820 from the end 9816 of the retaining plate 9822 to the end 9863 of the dome-shaped portion 9824 is about 8-13 mm. In certain embodiments, the central bore 9826 defined by the tapered portion 9828 has a diameter of about 13-18 mm. The end face 9863 depicts a ring diameter of about 20-28 mm. Boot 9820 may be made of, for example, a resilient material, such as plastic or rubber. In one embodiment, shield 9820 is made of a material sold under the trademark Noryl GTX 830.

Shroud 9832 is shown in fig. 114-115 to be similar in shape and function to shroud 9820 above. The shroud 9832 is substantially annular in shape having a dome-shaped outer portion 9837, a tapered inner portion 9836, a central bore 9834, and a recess 9838. In one embodiment, the groove 9838 is adapted to receive and cover a spline flange (see, e.g., fig. 92 and 105). In one embodiment, the distance between surface 9839 and surface 9840 of shroud 9832 is about 16-29 mm. The outer diameter of the cup 9832 is, for example, 33-40 mm. Thus, the inner diameter of boot 9832 at recess 9838 may be between 31-38 mm. In certain embodiments, the central bore 9834 has a diameter of about 12-18 mm. In certain embodiments, boot 9832 may be made of a resilient material, such as plastic or rubber. In one embodiment, shield 9820 is made of a material sold under the trademark Noryl GTX 830.

Referring now to fig. 116 and 118, idler bushing 8804 is shown. Certain embodiments of idler bushing 8804 have some of the same features as the inner bushing embodiment described above with reference to figures 77-82D related to the idler assembly. Idler bushing 8804 has a generally tubular body 9841 with an outer diameter of about 16-22mm, an inner diameter of about 13-19mm, and a length of about 28-34 mm. Idler bushing 8804 additionally includes a through bore 9847 that is adapted to receive shift rod nut 8816. In one embodiment, the holes 9847 are cut such that the distance between their flat faces 9849 is about 9-14 mm. In one embodiment, the idler bushing 8804 is additionally provided with a clip slot 9845 for receiving a clip 9891, which clip 9891 helps secure the shift cam 8806 (see fig. 88).

As shown in fig. 119-120, the shift rod nut 8816 is a generally rectangular cylinder having a threaded bore 9855 adapted to be threaded onto the shift rod 4816. In one embodiment, the shift rod nut 4816 includes a ramp 9851 that provides clearance for other components of the idler assembly 8802 (see fig. 88), but allows the shift rod nut 8816 to maximize the reaction contact surface between the shift rod nut 8816 and the abutment surface of the shift cams 8806. In one embodiment, shift rod nut 8816 has a height of about 20-26mm, a width (dimension perpendicular to bore 9855) of about 6-12mm, and a depth (dimension parallel to bore 9855) of about 7-13 mm.

Referring now to fig. 121-1255, the shift cam 8806 is generally an annular plate having a cam profile 9862 on one surface and cam extensions 9863 extending axially on opposite sides of the cam profile 9862. In some embodiments, the cam extension 9863 includes a bearing race 8814 formed thereon. The bearing race 8814 is preferably adapted to allow free rolling of the bearing balls and to withstand axial and radial loads. In one embodiment, the shift cam 8806 is provided with beveled edges 9860 on opposite sides of the cam profile 9862 to facilitate the flow of lubricant to the radial components within the idler assembly 8802 (see fig. 88), including the bearing races 8814, 8812. In some embodiments, the beveled edge 9860 is angled at an angle of about 6-10 degrees from vertical (in the plane of the cross-section shown in FIG. 123).

For some applications, the shift cam profile 9862 is manufactured according to the values tabulated in the table shown in fig. 125. The Y value is referenced to the center of the center hole 8817 and the X value is referenced to the end surface 8819 of the shift cam extension 9863. The first point PNT1 of the shift cam profile 9826 is on a surface 8821 that is located a horizontal distance of approximately 7-9mm from surface 8819, more precisely 8.183mm in the illustrated embodiment. In one embodiment, the outer diameter of the shift cam 8806 is approximately 42 mm to 50mm and the diameter of the central bore 8817 is approximately 16 mm to 22 mm. In one embodiment, the radius of the bearing race 8814 is about 2-4 mm. In some applications, the shift cam 8806 can be provided with a beveled edge 8823, the beveled edge 8823 being angled approximately 13-17 degrees from horizontal (in the plane of the cross-section shown in figure 123). Among other things, the beveled edge 8823 helps provide sufficient clearance between the shift cam 8806 and the power rollers 4802 when the transmission ratio of the transmission is at one of its extremes. The shift cam 8806 can be made of, for example, a steel alloy, such as bearing steel SAE 52100.

With reference to fig. 126-130, the traction ring 8825 will now be described. The traction ring 8825 is generally a circular ring having a traction surface 8827, the traction surface 8827 adapted to contact the power rollers 4802 and to transmit torque through a layer of friction or traction fluid between the traction surface 8827 and the power rollers 4802. Preferably, the traction surface 8827 does not have inclusions. In one embodiment, the traction ring 8825 is integral with an axial load cam 8829 that facilitates generating axial clamping forces and transferring torque within the CVT 8700. The traction ring 8825 is further provided with a slot 8831 adapted to receive, support and/or retain a torsion spring, such as torsion spring 5002 (see fig. 63A-63F) or torsion spring 8851 (see fig. 131 and 134). Additional details regarding the traction ring embodiment are provided above with reference to fig. 62A-62E and associated text.

In one embodiment, the axial load cam 8829 includes a set of ramps having a ramp profile 8833 best shown in fig. 129. In certain embodiments, the ramp profile 8833 includes a first inclined substantially planar portion 8835 blended into a radius portion 8836. The radius portion 8836 transitions into a substantially planar portion 8837, the planar portion 8837 transitioning into a radius portion 8839 with a second angled portion 8841. The features of the ramp profile 8833 are enlarged and slightly distorted in fig. 129 for clarity. Additionally, in some embodiments, the ramp is helical, and this feature is not shown in fig. 129. Preferably, the transitions and blends of portions 8835, 8836, 8837, and 8839 are tangential, not including sharp or abrupt portions or points. As previously described, a set of rollers (e.g., rollers 6404, 6405) is provided to transmit torque and/or axial force between the traction ring and a drive element (e.g., cam driver 4908 or output drive ring 8710). Although the rollers 6404, 6405 are shown as cylindrical rollers, other embodiments of the CVT8700 can use spherical, barrel, or other types of rollers.

Given that the rollers used have a radius R, the radius portion 8836 preferably has a radius of at least 1.5R (1.5R), and more preferably at least two R (2R). In one embodiment, radius portion 8836 has a radius of between 6-11mm, more preferably between 7-10mm, and most preferably between 8-9 mm. In certain embodiments, the planar portion 8837 has a length of about 0.1-0.5mm, preferably about 0.2-0.4mm, and most preferably about 0.3 mm. Radius portion 8839 preferably has a radius of about one-quarter R (0.25 ANGSTROM R) to R, more preferably about one-half R (0.5 ANGSTROM R) to nine-tenths R (0.90 ANGSTROM R). In one embodiment, radius portion 8839 has a radius of about 2-5mm, more preferably 2.5 to 4.5mm, and most preferably about 3-4 mm. The angled portion 8841 is angled at an angle θ of about 30-90 degrees, more preferably about 45-75 degrees, and most preferably about 50-60 degrees, relative to the plane 8847 along line 8845.

During operation of the CVT8700, for example, when the CVT8700 is actuated in a drive direction or under torque, the rollers 6404 tend to ride up in the direction 8843, generating an axial load and transmitting torque. When the CVT8700 is actuated in a direction 8845 opposite the drive direction 8843 (meaning the unloading direction, for embodiments where the load cam 8829 is a non-bidirectional cam), the roller 6404 depresses the first inclined portion 8835, follows the first radius portion 88365, rolls along the planar portion 8837, effectively encountering a positive stop, so that the roller 6404 cannot roll within the radius portion 8839 and cannot move past the relatively steeply inclined portion 8841. The ramp profile 8833 ensures that the roller 6404 is not constrained or trapped at the bottom of the ramp, which ensures that the roller 6404 is always in a position to provide the required torque or axial load. In addition, the ramp profile 8833 ensures that when the CVT8700 is operated in the direction 8845, the rollers 6404 do not produce an axial or torque loading effect that deteriorates the spinning condition of certain components of the CVT 8700. It should be noted that in some embodiments, the planar portion 8837 does not include the load cam profile 8833. In such embodiments, radius portions 8836 and 8839 may have the same or different radii. In one embodiment, the flat portion 8835 simply transitions to a radius portion 8836, the radius portion 8836 having a radius substantially consistent with the radius of the roller, the flat portion 8837, the radius portion 8839, and the flat portion 8841 are not used.

Referring now to fig. 131-134, certain embodiments of torsion spring 8851 have some of the same features as the embodiment of torsion spring 5002 described above with reference to fig. 63A-63F. In the embodiment illustrated in fig. 131-134, the torsion spring 8851 need not be provided with a helical state. Also, the torsion spring 8851 may be provided as a length of wire having the requisite curved ends 8853, 8855. The bent end 8855 has a bent portion 8857 bent approximately 90 degrees relative to the long portion 8861 of the torsion spring 8851; in certain embodiments, curved portion 8857 has a length of about 3-4 mm. The curved end 8853 has a bend 8859 that is about 160 degrees curved relative to the long portion 8861. In certain embodiments, bend 8859 is about 10-14mm long. Bend 8859 is then transitioned to bend 8863, which is about 3.5-4.5mm long, with bend 8863 being at about 75-85 degrees relative to the parallel to bend 8859. In one embodiment, the overall center length of torsion spring 8851 is approximately 545 and 565 mm.

Referring now to fig. 135-138, certain embodiments of input driver 8602 have some of the same features as the embodiment of input driver 6904 described above with reference to fig. 67A-67E. The input drive 8602 includes a groove 8865 on an inner diameter portion thereof to facilitate flow of lubrication to the bearing races 6706, 6708. In one embodiment, the input driver 8806 can also include a set of splines 8867 with at least one spline 8869 having a different circumferential length than the remaining splines. In the illustrated embodiment, the splines 8869 have a longer circumferential dimension than the remaining splines; however, in other embodiments, the splines 8869 may have a shorter circumferential dimension than the remaining splines. For example, the distinguishable splines 8869 may be used to facilitate assembly by ensuring that components, such as the freewheel 8890 (see fig. 148-147), mate with the input driver 8602 in the proper configuration.

Referring now to fig. 139-141, certain embodiments of torsion coils 8604 have some of the same features as the embodiment of torsion coil 4906 described above with reference to fig. 68A-68B. The torsion plate 8604 can be provided with a set of splines 8871, each of which has a drive contact 8873 and a transition portion 8875. Drive contact 8873 is preferably made to conform to the profile of cooperating splines in cam driver 4908 (see fig. 70A-70C and associated text). In certain embodiments, the transition portion 8875 can have a contour that conforms to the drive contact 8873; however, as shown in the embodiment of fig. 138-140, where the transition portion 8875 may be planar, results in lower processing costs. The torsion plate 8604 may be made of, for example, medium carbon steel with a minimum HRC 20-23. In one embodiment, the torsion plate 8604 is made of a steel alloy, such as 1045 CRS. Because of the torque levels involved in some applications, it has been found that the torsion plate 8604 preferably is not made of a soft material. Fig. 142-143 show an input assembly 8877 including an input driver 8602 and a torsion disc 8604. In one embodiment, the input driver 8602 is welded to the torsion plate 8604. However, in other embodiments, the input driver 8602 may be secured or attached to the torsion plate by a suitable adhesive, dowel pins, bolts, press fit, or the like. In other embodiments, the input assembly 8877 is integral with the input driver 8602 and the torsion disc 8604.

One embodiment of a roller axle 9710 is shown in fig. 144-146. Certain embodiments of roller axle 9710 have some of the same features as the embodiments of roller axles 4826, 4827 described with reference to fig. 54A-55. The roller axle 9710 may be provided with an unrestrained slot 9712 for helping to retain the oblique roller 5206 (see, e.g., fig. 52A-52B). During assembly of the roller leg assembly 4830, the skew roller 5206 is mounted to an end 9714 of the roller axle 9710. To hold the ramp on the shaft 9710 and abut against the leg 4824, the bore 5502 is enlarged by a suitable tool. As the sides of the bore 5502 expand radially, the slot 9716 partially collapses and the tip 9716 bends toward the ramp 5206. In this way, the tip 9716 retains the skew roller on the roller axle 9710. In effect, after enlarging the bore 5502, the tip 9716 acts as a retaining clip.

Referring now to fig. 147-148, the flywheel 8890 is described. Certain embodiments of flywheel 8890 have some of the same features as the embodiment of flywheel 4902 described above with reference to fig. 71A-71D. In one embodiment, the freewheel 8890 includes a set of internal splines 8892. The splines 8894 of the set of splines 8892 have a different circumferential dimension than the other splines. Preferably, the splines 8894 are selected to mate with a corresponding set of spline bottoms of the input driver 8602. Thus, the asymmetrically splined freewheel 8890 cooperates with the asymmetrically splined input driver 8602. In the embodiment illustrated in fig. 148-147, the flywheel teeth 8896 are centrally located relative to the width of the flywheel 8890.

Referring now to FIG. 149, there is shown a torsion spring 1492 that is similar to torsion spring 5002 (see FIGS. 63A-63E) and torsion spring 8851 (see FIG. 131-. Torsion spring 1492 can have a combination of the features of torsion springs 5002, 8851. In certain embodiments, the torsion spring 1492 may include a uniform curvature 1494 and/or a uniform curvature 1496. In one embodiment, the bend 1494 and/or the bend 1496 are portions along the torsion spring 1492 that have a biased curvature, which facilitates the conformance of the torsion spring 1942 with the roller cage 5004.

Referring to fig. 150, in some embodiments without the bends 1494, 1496 (depending on the diameter and/or stiffness of the spring wire), the torsion spring 1492 has portions 1494A, 1496A that do not conform to the curvature of the roller cage 5004, thereby trapping the traction ring 6200 within the channel 6206 (see fig. 62A-62E). However, the bends 1494, 1496 facilitate assembly of the axial force and/or preload subassembly shown in fig. 64E-64H, significantly improving its operation. As shown in fig. 151, in certain embodiments, the bends 1494, 1496 bend toward the retaining extension 6406 when the torsion spring 1592 is in its operating state (received and wound in the traction ring 6200 and the roller cage 5004); thus, the restriction that the torsion spring 1492 creates on the traction ring 6200 is often alleviated.

As best shown in fig. 150, the portions 1494A, 1496A, which may have a biased curvature of the bends 1494, 1496, may be disposed at the terminal 0-90 degrees of the torsion spring 1492 relative to its retained state within the roller cage 5004. More preferably, the bends 1494, 1496 are formed at 5-80 degrees of the terminal, most preferably at 10-70 degrees of the terminal. In some embodiments, the extreme bends 1498, 1499 of the torsion spring 1492 are not included in the above sections. That is, bends 1494, 1496 do not include bends 1498, 1499 and/or torsion spring 1492 is adjacent a short portion of bends 1498, 1499. In some embodiments, the radii of the bends 1494, 1496 may be 110-190% of the radius of the roller cage 5004. The length of the arc of the bends 1494, 1496 is defined by an angular range, for example, preferably from 0 degrees to at least 90 degrees, more preferably from 0 degrees to at least 60 degrees, and most preferably from 0 to at least 30 degrees.

It should be noted that the above description has dimensions provided for specific components or subassemblies. The dimensions or ranges of dimensions are provided in order to comply as much as possible with certain regulatory requirements, such as best mode. However, the scope of the invention described herein is defined only by the language of the claims, and thus, none of the above dimensions should be considered limiting on the embodiments of the invention unless any claim specifically defines a dimension or range of dimensions.

The foregoing description details specific embodiments of the invention. It will be appreciated, however, that no matter how detailed the foregoing appears, the invention can be practiced in many ways. And as noted above, it should be noted that the use of particular terminology when describing certain features or aspects of the invention should not be taken to limit the terminology re-defined herein to including particular characteristics of the features or aspects of the invention with which that terminology is associated.

Claims (5)

1. A Continuously Variable Transmission (CVT) comprising:

a plurality of spherical power rollers, each power roller adapted to rotate about a tiltable axis;

first and second traction rings;

an idler wheel mounted about the spindle;

wherein each of said spherical power rollers is interposed between said first and second traction rings and said idler in a three-point contact;

a load cam driver;

a first plurality of load cam rollers, wherein the first plurality of load cam rollers are interposed between the load cam driver and the first traction ring;

a thrust bearing;

a hub shell, wherein the thrust bearing is located between the load cam driver and the hub shell;

a hub shell cover; and

a second plurality of load cam rollers interposed between the second traction ring and the hub shell cover.

2. The CVT of claim 1, wherein the first traction ring is coupled to a first torsion spring.

3. The CVT of claim 2, wherein the first traction ring has a first set of ramps.

4. The CVT of claim 2, wherein the second traction ring is coupled to a second torsion spring.

5. The CVT of claim 4, wherein the second traction ring has a second slope.