JP2000074165A - Variable diameter pulley - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a variable diameter pulley with a variable effective diameter for belt wound round it, small-sized, of excellent durability and ensured in smooth shift operation by using diaphragm springs for torque transmission. SOLUTION: Pulleys 2 and 3 fitting with a first 11 and a second diaphragm spring 12 are energized in the respective directions to approach the other pulley members 3 and 2. The bore part 61 of each diaphragm spring 11/12 is rotatably coupled with the mating pulley 2/3 in a single piece. The outside parts 62 of the springs 11 and 12 are rotatably coupled with a receptacle member 17 of a coupling member 13 in a single piece. The coupling member 13 is formed on a rotary shaft 1 consolidatedly.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a variable diameter pulley capable of changing an effective diameter of a belt.

[0002]

2. Description of the Related Art Conventionally, in a variable diameter pulley, a belt or a power transmission ring which engages with the belt is sandwiched between a pair of pulleys provided movably in the axial direction around a rotary shaft. A spring member is provided for urging the pulley main bodies in directions approaching each other. Among such variable-diameter pulleys, there is a type in which only one of the pulleys is moved in the axial direction to change the effective diameter. In this case, the position of the belt center changes with the change in the effective diameter. The belt is deformed between the variable-diameter pulley and another fixed pulley or the like, which is not preferable in terms of durability.

[0003] Therefore, a torque cam mechanism is provided between the rotary shaft and each pulley main body, and a phase shift generated between the rotary shaft and each pulley main body is converted into an axial displacement of each pulley main body. Thus, it is conceivable that both pulley main bodies approach each other with an equal stroke amount. In this case, the position of the belt center can be kept constant irrespective of the shift, but the structure becomes complicated.

When only one pulley main body is directly urged by the above-mentioned spring member, the other pulley main body is urged via one pulley main body and a pair of torque cam mechanisms, so that a smooth operation is achieved. May not be possible.

[0005]

Therefore, both pulleys are rotatable around the rotating shaft and movable in the axial direction, and the inner peripheral edge and the outer peripheral edge of the disc spring interposed therebetween correspond to the corresponding pulley main bodies. It is conceivable that the disc spring and the rotating shaft are integrally rotatably connected by a connecting member. The two pulleys, the disc spring, and the connecting member rotate integrally, and torque is transmitted from the belt to the rotating shaft via the two pulleys, the disc spring, and the connecting member sequentially.

In this case, the torque cam mechanism is eliminated and both pulleys can be directly urged by the disc springs, so that the pulleys can be operated smoothly and a smooth shift can be achieved. Further, by connecting the connecting member and the disc spring as described below, the outer peripheral edge and the inner peripheral edge can be given opposite displacements in the same direction when the disc spring is compressed.
That is, a plurality of through-holes are provided in a circumferentially equidistant manner at a radially intermediate portion of the disc spring, a plurality of shaft-like portions penetrated through these through-holes are provided in the connection member, and each shaft-like portion is used as a fulcrum. The inner and outer peripheral edges of the disc spring are deformed. By setting the position of the fulcrum to a predetermined position, the outer peripheral edge and the inner peripheral edge of the disc spring can be displaced in opposite directions and by the same displacement amount.

However, torsion stress due to torque transmission is applied to the entire disc spring, and stress concentrates particularly around a through hole formed in a radially intermediate portion which is a fulcrum position of bending, which causes a problem in durability. I am concerned. The present invention has been made in view of a new problem expected when torque is transmitted via a diaphragm spring, and has a variable diameter pulley having a simple structure, capable of smooth shifting, and having excellent durability. The purpose is to provide.

[0008]

Means for Solving the Problems As means for solving the problems to achieve the above object, the aspect of the invention described in claim 1 is as follows.
A variable diameter pulley capable of changing an effective diameter with respect to a belt, comprising first and second annular pulley bodies provided rotatably about a rotation axis and relatively movable in an axial direction with respect to each other; And a pair of tapered power transmission surfaces respectively formed on opposing surfaces of the pulley, and the pair of power transmission surfaces are eccentrically sandwiched between the shaft centers of both pulleys, and the belt is wound around the outer peripheral surface. Power transmission ring, a biasing means for biasing both pulley main bodies in a direction approaching each other, and a connecting means for connecting the biasing means and the rotating shaft so as to be integrally rotatable, the biasing means includes: Including first and second diaphragm springs, the inner diameter portion or outer diameter portion of each diaphragm spring is rotatable integrally with the corresponding pulley main body while its axial movement is restricted. Together is, the outer diameter or the inner diameter portion of the diaphragm spring is characterized in that it is engaged integrally rotatable engaged in a state where axial movement is restricted with respect to the connecting means.

In this configuration, torque is transmitted from the belt to the rotating shaft via the power transmission ring, each pulley main body, each diaphragm spring, and the connecting means. At this time, both the pulley main bodies, both the diaphragm springs and the connecting means rotate integrally. The biasing means is composed of a pair of diaphragm springs, and torque is transmitted between the inner and outer diameters of each diaphragm spring, eliminating the need for conventional through-holes, which may cause stress concentration. There is no.

Further, the transmission torque is shared and transmitted by the two diaphragm springs, and the torque transmitted by each diaphragm spring can be reduced. Thereby, the stress of the diaphragm spring can be remarkably reduced as compared with the urging force of the entire urging means, so that the durability can be improved while reducing the size of the diaphragm spring.

Furthermore, by making the urging forces of both diaphragm springs equal, the axial displacement of both pulleys can be made substantially equal. According to a second aspect of the present invention, in the first aspect, the outer diameter portion of each diaphragm spring is formed with a plurality of connecting protrusions for engaging with the plurality of connecting grooves of the corresponding member, respectively, in a circumferentially equidistant manner. So that each connecting projection contributes only to torque transmission,
The radial end of the connection protrusion and the groove bottom of the connection groove are not in contact with each other, and the axial load is received by the outer diameter portion between adjacent connection protrusions of each diaphragm spring. Things.

In this embodiment, an axial load as a reaction force of a force for urging the pulley main body in the axial direction is received by the outer diameter portion excluding the connection protrusion, and the connection protrusion of the outer diameter portion of the diaphragm spring is provided. Contribute only to torque transmission. Accordingly, as a result that high stress is not generated in the connection projection, the durability of the diaphragm spring is improved. According to a third aspect of the present invention, in the first aspect, the outer diameter portion of each diaphragm spring includes a plurality of torque transmitting angle-shaped connecting projections which are respectively engaged with a plurality of connecting grooves of a corresponding member. The connecting protrusions have at least a slope on the rotation direction side including a tapered engaging portion that is smoothly continuous with an outer diameter portion between the connecting protrusions, and the connecting groove corresponding to each connecting protrusion is as described above. It is characterized in that it includes a tapered engaging portion that matches the engaging portion.

When transmitting the torque by the diaphragm spring, if the root portion of the slope on the rotation direction side of the angled connection protrusion (the boundary portion between the slope and the outer diameter portion between the connection protrusions) has a discontinuous shape, the height is high. The stress tends to concentrate.
On the other hand, in this aspect, since the tapered engagement portion included in the inclined surface on the rotation direction side smoothly continues to the outer diameter portion between the connection protrusions, stress concentration can be reduced. Further, at the time of transmitting the torque, the tapered portion of the inclined surface on the rotation direction side of each connecting projection is pushed toward the center of the diaphragm spring, so that the diaphragm spring does not rattle and there is no misalignment with the pulley main body. Further, when a similar tapered engaging portion is provided on the inclined surface on the side opposite to the rotation direction, it is advantageous because stress concentration is reduced and misalignment is suppressed.

[0014] The aspect of the invention described in claim 4 is claim 1.
In 2 or 3, the first pulley main body includes a portion extending through the second pulley main body in the axial direction and extending to the back side of the power transmission surface of the second pulley main body. The peripheral portion is received by a portion extending to the rear side via a slide bearing. In the present embodiment, the following operation is provided. That is, if the portions supporting the inner circumferences of both pulley main bodies are arranged apart from each other in the axial direction, in order to reduce the size, the length in the axial direction of the portion supporting the inner circumferences (that is, sliding) is inevitable. Length) becomes shorter.

On the other hand, in this aspect, since at least a part of the arrangement range of the portion supporting the inner periphery of each pulley main body can be overlapped in the axial direction, the portion supporting the inner periphery of each pulley main body can be overlapped. The axial length can be made sufficiently long, and as a result, each pulley main body can be stably supported without increasing the size of the whole. The aspect of the invention described in claim 5 is:
In any one of claims 1 to 4, a pair of seal members held by the main body of the second pulley is provided between an inner peripheral portion of the main body of the second pulley and a portion extending to the rear side.
It is arranged side by side on the tip side of the portion extending to the rear side than the slide bearing, the interference of the seal member closer to the slide bearing is greater than the interference of the seal member far from the slide bearing. The second pulley main body has a relief hole between its inner peripheral portion and the portion extending to the back side and communicating an intermediate region between the pair of seal members to the outside. Things.

In this embodiment, since the seal member is provided in a double form, it is possible to prevent muddy water from entering between the sliding bearing and the power transmission surface when the variable diameter pulley is applied to an automobile. . As a result, it is possible to prevent an increase in the sliding resistance of the pulley main body due to muddy water intrusion,
In addition, it is possible to prevent the power transmission ring from slipping with respect to the power transmission surface due to the intrusion of muddy water, thereby preventing a required speed ratio from being obtained.

Moreover, even if the muddy water passes through the sealing member on the front end side having a small interference, the infiltration of the muddy water is prevented by the sealing member on the inner side with the large interference, and the muddy water enters between the two sealing members. Muddy water is released to the outside through the release hole by centrifugal force during rotation. As a result, the possibility that muddy water enters between the sliding bearings and the power transmission surface can be significantly reduced.

According to a sixth aspect of the present invention, in any one of the first to fifth aspects, each of the diaphragm springs is formed by stacking a plurality of disc springs having different spring characteristics. The first and second diaphragm springs are important components for determining the relationship between the gear ratio of the variable diameter pulley and the belt tension. However, when each diaphragm spring is constituted by one piece,
Since the spring performance is limited, the degree of freedom in design is low. On the other hand, in the present embodiment, since a plurality of disc springs having different spring performances are combined, a desired desired spring performance can be obtained as a whole, and the design of the driving force transmission system including the variable diameter pulley can be freely performed. The degree increases. In particular, it is preferable that the spring characteristic is as flat as possible such that the load gradually increases with respect to the displacement in the use area. To realize this, a first disc spring whose load monotonically increases with an increase in displacement, a small displacement region where the load monotonically increases with an increase in displacement, a medium displacement region where the load monotonically decreases, and Using a second disc spring having a large displacement region that increases monotonically and superimposing it to obtain a relatively flat region as a combination spring characteristic in the medium displacement region, and using this as a use region can be exemplified. it can.

[0019]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 shows the first embodiment of the present invention.
It is sectional drawing of the variable diameter pulley which concerns on embodiment. Referring to FIG. 1, the variable diameter pulley is capable of changing the effective diameter of a wound belt, and is applied to at least one of a driving pulley and a driven pulley.

The variable diameter pulley is provided with a first
And a second annular pulley main body 2, 3, and power transmission surfaces 4, 5 are formed on opposing surfaces of the pulley main bodies 2, 3, respectively. The pair of power transmission surfaces 4 and 5 are tapered so as to be inclined in opposite directions, and the power transmission rings 6 having a substantially trapezoidal cross section are formed by the two power transmission surfaces 4 and 5. It is held so as to be eccentric with respect to the axis K (see FIG. 3).

A power transmission surface 8 to the belt 7 is formed on the outer peripheral surface of the power transmission ring 6, and the belt 7 is wound around the power transmission surface 8. A circumferential groove that meshes with the rib of the belt 7 is formed on the transmission surface 8. Both side surfaces of the power transmission ring 6 constitute power transmission surfaces 9 and 10 that contact the corresponding power transmission surfaces 4 and 5 to transmit torque. In addition, the variable diameter pulley includes first and second pulley main bodies 2,
3 as urging means for urging the third members 3 toward each other.
And the second diaphragm springs 11 and 12, and a connecting member 13 that integrally connects the two diaphragm springs 11 and 12 to the rotating shaft 1 so as to be integrally rotatable.

The connecting member 13 includes a disc-shaped flange 14 formed integrally with the end of the rotating shaft 1, a cylindrical flange 15 formed integrally with the outer periphery of the flange 14, and a flange 15 formed integrally with the flange 14. And a receiving member 17 fixed by screws 16. Inner diameter portion 6 of first diaphragm spring 11
1 and the outer diameter portion 62 are respectively engaged with the first pulley main body 2 and the connecting member 13 so as to be integrally rotatable. The inner diameter portion 61 and the outer diameter portion 62 of the second diaphragm spring 12 are The pulley main body 3 and the connecting member 13 are engaged with each other so as to be integrally rotatable.

As a result, the two pulley main bodies 2 and 3, the two diaphragm springs 11 and 12, and the connecting member 13 rotate integrally. For example, when this variable-diameter pulley is applied to a driven pulley, the running belt 7 is connected to the rotating shaft 1 via the power transmission ring 6, the pulley main bodies 2 and 3, the diaphragm springs 11 and 12, and the connecting member 13. Torque is transmitted.

Referring to FIG. 1 and FIGS. 2 (a) and 2 (b), the inner diameter portion 61 of each diaphragm spring 11 has
A plurality of radial connection grooves 63 are formed on the outer circumference of the outer diameter portion 62. A plurality of radial connection protrusions 64 are formed on the outer diameter portion 62. The first pulley main body 2 includes a holed disk portion 18 having the tapered power transmission surface 4 and a boss portion 20 which is integrally rotatably connected to the inner periphery of the disk portion 18 by a key 19. Have. A small-diameter screw portion 21 is formed at one end of the boss portion 20, and a nut 22 screwed into the screw portion 21 presses the disk portion 18 via a washer 23, thereby forming an inner peripheral edge of the disk portion 18. Is formed on the stepped portion 2 formed on the outer periphery of the boss portion 20.
4, the disk portion 18 is fixed to the boss portion 20 so as to be integrally movable in the axial direction. Since the relative rotation between the boss portion 20 and the disk portion 18 is regulated by the key 19, the screw portion 21 can be prevented from rotating by fixing the disk portion 18 when tightening the nut 22. This allows
Since the rotation can be easily stopped, the nut 22 can be easily tightened without damaging the material inside the variable diameter pulley.

At the other end of the boss 20, there is formed a cylindrical portion 25 extending to an intermediate portion in the axial direction, and the rotary shaft 1 is coaxially inserted into the cylindrical portion 25. The boss 20 is slidably supported in the axial direction on the peripheral surface of the rotary shaft 1 via a bush 26 as a sliding bearing. 27 is a retaining ring for fixing the bush 26 to the tubular portion 25. The second pulley main body 3 includes a disk portion 28 with a hole having the tapered power transmission surface 5, and a cylindrical boss portion 29 formed on the inner periphery of the disk portion 28. The boss portion 29 of the second pulley main body 3 surrounds the boss portion 20 of the first pulley main body 2 and is slid in the axial direction by the boss portion 20 of the first pulley main body 2 via a bush 30 as a sliding bearing. It is freely supported. Reference numeral 31 denotes a retaining ring for fixing the bush 30 to the inner periphery of the boss 29. On the back surface 41 of the power transmission surface 5 of the main body 3 of the second pulley, a plurality of plate-shaped connection protrusions 42 fitted into connection grooves 63 (described later) of the inner diameter portion 61 of the second diaphragm spring 12 are provided. It is formed evenly. The inner diameter portion 61 of the second diaphragm spring 12 urges the second pulley main body 3 toward the first pulley main body 2 via the back surface 41.

The boss 20 of the first pulley main body 2 is
Of the power transmission surface 5 of the second pulley main body 3 through the boss portion 29 of the main pulley main body 3, and the boss portion 20 constitutes a portion extending to the rear side of the second pulley main body 3. are doing. The boss portion 20 as a portion extending to the back side
(That is, the end of the cylindrical portion 25)
An annular connecting portion 32 for integrally connecting the inner peripheral portion 61 of the first diaphragm spring 11 and the inner diameter portion 61 of the first diaphragm spring 11 is integrally formed.

The connecting portion 32 is a disk-shaped pressing plate portion 33 for pressing the inner diameter portion 61 of the first diaphragm spring 11 in the axial direction, and is radially formed on the pressing plate portion 33 by being equally circumferentially distributed. And a plurality of connection projections 34 formed.
The above-mentioned pressing plate portion 33 is provided with the first diaphragm spring 1.
The first pulley main body 2 is urged by the inner diameter portion 61 via the connecting portion 32 in a direction approaching the second pulley main body 3. In addition, the plurality of connection protrusions 34
Of the inner diameter portion 61 of the diaphragm spring 11.

Referring to FIGS. 3 and 4, the receiving member 17 of the connecting member 13 has a T-shaped cross section, and projects radially inward from the axial center of the inner periphery of the main body 35. And an annular receiving plate 36. On both side surfaces of the receiving plate 36, a plurality of radial connecting grooves 37 are respectively formed in a circumferentially equidistant manner. Each connection groove 37 reaches a radially intermediate portion of the main body 35. Reference numeral 38 denotes a screw insertion hole through which the screw 16 is inserted. 39 is a groove bottom of the connection groove 37;
Reference numeral 40 denotes a corner between the main body 35 and the receiving plate 36.

Referring to FIG. 5 and FIG. 6, which is a cross section taken along line CC of FIG. 5, diaphragm springs 11 and 12 are shown.
Of the connecting projection 64 in the radial direction and the receiving member 17
Is not in contact with the groove bottom 39 of the connection groove 37, so that each connection protrusion 64 contributes only to torque transmission. In addition, the portion of the outer diameter portion 62 between the adjacent connection protrusions 64 of the diaphragm springs 11 and 12 is
It comes into contact with the corner portion 40 of the receiving member 17 to receive an axial load. In FIG. 6, each of the diaphragm springs 11 and 12 is shown one by one for simplification.

In the present embodiment, the tension adjusting mechanism (not shown) adjusts the tension of the belt 7 so that the power transmission ring 6 is pressed against the urging force of the diaphragm springs 11 and 12.
As shown in FIG. 7, the pulley main bodies 2 and 3 are decentered while moving away from each other, so that the effective diameter D of the wound belt 7 can be changed. Each pulley main body 2,
Since the diaphragm springs 11 and 12 are interposed between the connecting member 3 and the connecting member 13, respectively, the torque can be shared and transmitted by the two diaphragm springs 11 and 12, so that the stress of each of the diaphragm springs 11 and 12 can be reduced. In addition, since there is no risk of stress concentration unlike the case where a single diaphragm spring is supported by drilling, the substantial strength of the diaphragm springs 11 and 12 can be improved. Therefore, even if the diaphragm springs 11 and 12 are small, high durability can be realized, and as a result, a variable diameter pulley that is small and has excellent durability can be obtained.

The two diaphragm springs 11, 1
By making the urging forces of the two equal, the axial displacements of the two pulley bodies 2 and 3 can be made substantially equal.
As a result, the center position in the axial direction between the two pulley bodies 2 and 3 can be kept constant, the position of the width center L of the belt 7 can be kept substantially constant. Therefore, for example, a complicated mechanism such as a torque cam mechanism is not required, and a smooth shift can be achieved with a simple structure.

Further, each of the diaphragm springs 11,
Since the connection projection 64 of the outer diameter portion 62 of the twelve contributes only to the torque transmission, high stress is not generated in the connection projection 64, and the durability of the diaphragm springs 11 and 12 is further improved. Further, since at least a part of the axial arrangement range of the portion supporting the inner circumference of each of the pulley bodies 2 and 3 can be overlapped, the axial length of the portion supporting the inner circumference of each of the pulley bodies 2 and 3 can be overlapped. Can be long enough. In other words, the bushings 26 and 30 can be kept within a predetermined axial range while the axial lengths thereof are sufficiently long. As a result, each pulley main body 2, 3 can be stably supported without increasing the size of the whole.

Next, FIGS. 8A and 8B show a second embodiment of the present invention. Referring to these figures, the present embodiment is different from the embodiments of FIGS. 2 and 5 in that the outer diameter portion 6 of the diaphragm spring 11 (12) is different.
The connection protrusions 66 provided on the second protrusion 2 have a mountain-like shape having a top 67 as a radially outer edge, and the slopes on both sides sandwiching the top 67 are tapered engagement portions 68 so that the connection protrusions 66, 6 are formed.
That is, the outer diameter portion 62 between the six portions is smoothly connected via an R-shaped portion. The connecting groove 69 of the receiving member 17 of the connecting member 13 also has a tapered engaging portion 70 that matches the engaging portion 68 of the connecting protrusion 66. On the other hand, the inner corner of the connection groove 63 of the inner diameter portion 61 is formed as an R-shaped portion having a diameter nearly half of the groove width to reduce stress concentration.

In this embodiment, since the tapered engaging portion 68 of the connecting protrusion 66 smoothly continues to the outer diameter portion 62 between the connecting protrusions 66, stress concentration can be reduced. In transmitting the torque, in particular, each connecting projection 62
The pressing force of the corresponding engaging portion 70 on the receiving member 17 pressing the tapered engaging portion 68 on the rotation direction side acts on the outer diameter portion 62 at a position equidistantly circumferentially. The backlash of the spring 11 (12) is prevented, and the center of the diaphragm spring 11 (12) is aligned with the center of the receiving member 17 (that is, the rotation axis K which is the center of the pulley bodies 2 and 3). Is done.

Next, FIGS. 9 and 10 show a third embodiment of the present invention. In the present embodiment, as shown in FIG. 9, the first and second diaphragm springs 11,
12 is configured as a composite spring in which first and second disc springs 43 and 44 having different spring characteristics are overlapped. Referring to FIG. 11, first disc spring 43 has a substantially linear spring characteristic in which the load monotonically increases with an increase in displacement. On the other hand, the second disc spring 44 has a small displacement region in which the load monotonically increases with an increase in displacement, a medium displacement region in which the load monotonically decreases, and a large displacement region in which the load monotonically increases. The characteristics of the composite springs constituting the diaphragm springs 11 and 12 are relatively flat characteristics in which the load gradually increases with the increase in displacement in the medium displacement region. By setting this flat area as a use area, it is possible to prevent the power transmission ring 6 from being biased between the pulley main bodies 2 and 3 and the behavior from becoming unstable.

By using the composite spring, a desirable desired spring performance can be obtained as a whole, so that the degree of freedom in designing the driving force transmission system including the variable diameter pulley is increased. Next, FIG. 11 shows a fourth embodiment of the present invention. Boss portion 2 of second pulley main body 3
1 in that it is supported by a cylindrical portion 25 integrally fixed to the first pulley main body 2 via a bush 30 as a slide bearing press-fitted into the inner peripheral surface thereof. Same as the form. However, in the present embodiment, the bush 30 is fitted into the inner peripheral surface of the boss 29 from the power transmission surface 5 side. Also, on the inner peripheral surface of the boss 29,
The first portion is located on the tip side of the boss portion 29 with respect to the bush 30.
And second O-rings 45 and 46 are arranged. Further, between the inner peripheral surface of the boss portion 29 and the outer peripheral surface of the cylindrical portion 25, an intermediate region between the first and second O-rings 45 and 46 penetrates the boss portion 29 in the radial direction. Alternatively, it communicates with the outside through a plurality of escape holes 47.

The first O-ring 45 is positioned by the end face of the bush 30 at the innermost part of the circumferential groove into which the bush 30 is fitted.
Are accommodated in an annular accommodation groove formed on the inner peripheral surface of the distal end portion. The interference of the first O-ring 45 with respect to the cylindrical portion 25 is set larger than the interference of the second O-ring 46.

According to the present embodiment, the first and second O
Since the rings 45 and 46 are provided, when the variable diameter pulley is applied to an automobile, muddy water is formed in the bush 30 for supporting the second pulley main body 3 and the V-shaped groove is defined by the power transmission surfaces 4 and 5. Can be prevented from entering. Thereby, it is possible to prevent the sliding resistance of the pulley main body 3 from increasing due to the intrusion of the muddy water, and the power transmission ring 6 slips with respect to the power transmission surfaces 4 and 5 due to the intrusion of the muddy water, so that the required It is possible to prevent the gear ratio from being lost.

In particular, a double seal is provided, and the sealability is high. Moreover, as described above, the first O-ring 45 on the back side with respect to the intrusion direction has a relatively large interference, and the sealing performance is relatively enhanced. The muddy water that has passed through the first O-ring 45 and has entered the intermediate region between the first and second O-rings 45 and 46 is released to the outside through the escape hole 47 by centrifugal force during rotation. Second O-ring 4 with a large interference
6 can be significantly reduced.

Next, FIG. 12 shows a fifth embodiment of the present invention. With reference to this figure, in the present embodiment, a stabilizer 48 for pressing the outer peripheral surface of power transmission ring 6 is provided. The stabilizer 48 is urged in a direction D opposite to the direction C in which the power transmission ring 6 is eccentric. The stabilizer 48 is provided on the transmission surface 8 on the outer peripheral surface of the power transmission ring 6.
A roller 49 that is in rolling contact with the oscillating arm, a swing arm 51 that rotatably supports the roller 49 at the distal end portion 50, a support portion 53 that swingably supports a base end portion 52 of the swing arm 51, An urging member 54 for elastically pressing the roller 49 against the transmission surface 8 of the power transmission ring 6 via the swing arm 51 is provided. Reference numeral 55 denotes a damping force generating member (a so-called damper) 55 for giving a damping force to the swing of the swing arm 51 by frictional resistance or viscous resistance.

In the present embodiment, the stabilizer 48 can prevent the rotation axis 56 of the power transmission ring 6 from falling with respect to the rotation axis K of the variable-diameter pulley and losing parallelism. . Here, at least the outer peripheral surface of the roller 49 is made of aluminum (aluminum alloy) so as not to damage the power transmission ring 6 made of a resin (for example, a phenol resin in which aromatic polyamide fiber, carbon fiber and graphite are blended). ) Or a resin (for example, polyamide 66). Also, a plurality of stabilizers are provided,
It is also possible to implement as a known configuration shown in Japanese Patent Application Laid-Open No. 299848.

The present invention is not limited to each of the above embodiments. For example, each of the diaphragm springs 1
The protrusions between the adjacent connection grooves 63 of the inner diameter portion 61 of the first and second inner portions 61 can also be configured to contribute only to the torque transmission similarly to the connection protrusions 64 of the outer diameter portion 62.
Further, the pulley main bodies 2 and 3 may be made of, for example, a tempered material of S55C, and at least the power transmission surfaces 4 and 5 may be subjected to nitriding treatment to improve wear resistance. If the power transmission surfaces 4, 5
If induction hardening is applied to the pulleys, the pulley main bodies 2 and 3 tend to be distorted by heat and the dimensional accuracy tends to deteriorate. To prevent this, the thickness of the pulley main bodies 2 and 3 must be increased. is necessary. On the other hand, when the nitriding treatment is performed as in the present embodiment, the influence of distortion due to heat is small, and the thickness of the hardened layer due to nitriding can be small. The wear resistance and self-lubrication of the power transmission surfaces 4 and 5 can be improved while reducing the size and weight of the power transmission surfaces 4 and 5. The nitriding treatment may be liquid nitriding or gas nitriding. Further, a so-called super-nitriding process in which a nitriding treatment is performed after a fluoridation treatment may be used.

In each of the above embodiments, the inner diameter of each of the diaphragm springs 11 and 12 is engaged with the corresponding pulley main bodies 3 and 2, and each of the diaphragm springs 11 and 1 is engaged.
2 is engaged with the connecting member 13. On the contrary, as shown in FIG. 13, the outer diameter of each of the diaphragm springs 11, 12 is changed to the corresponding pulley main bodies 94, 97.
And the inner diameter of each of the diaphragm springs 11 and 12 may be engaged with the connecting member 76. In FIG. 13, the first and second diaphragm springs 11 and 12 are disposed on both sides of both pulley bodies 94 and 97.

Referring to FIG. 13, a rotary shaft 71 as an input shaft is provided with a rolling bearing 75 on an inner peripheral surface of a base end of a boss 74 of a flanged cylinder 73 fixed to a fixing portion 72 by bolts 56. Supported rotatably. The variable diameter pulley that transmits the driving torque to the rotating shaft 71 is disposed around the boss 74. This variable diameter pulley
A connecting member 76 is provided. The connecting member 76 is a first hub 77 formed of a bottomed cylinder surrounding the periphery of the boss 74.
An annular plate portion 78 extending radially outward from one end of the first hub 77; a second hub 79 extending from a radially intermediate portion of the annular plate portion 78 to the opposite side of the first hub 77; An annular end face portion 80 extending radially inward from the other end of the hub 77 is provided.

An annular end plate 81 as a connecting member is fastened to an end surface portion 80 of the connecting member 76 at the tip end of the first hub 77 by screws 82 and press-fit pins 83. Are connected to the rotating shaft 71 by a key 84 so as to be integrally rotatable. A screw 85 integrally formed at the tip of the rotating shaft 71 penetrates the end plate 81, and the end plate 81 is sandwiched between a nut 86 screwed into the screw 85 and an end surface of the rotating shaft 71. , An end plate 81 is fastened to the rotating shaft 71.

The second hub 79 of the connecting member 76 is
Is rotatably supported on a peripheral surface of a base end portion thereof via a rolling bearing 87. The rolling bearing 87 disposed at the base end of the boss 74 includes a plurality of balls 90 as a plurality of rolling elements held by a retainer between an inner ring 88 and an outer ring 89.
Is interposed. The fit between the inner ring 88 and the boss 74 is a slight clearance fit, and the outer ring is
It is tightly fitted to the hub. The radial clearance of the bearing is made larger than usual. However, the amount of the radial gap is set to be slightly smaller than the amount of deformation of the outer ring 89 subjected to the generated moment load. As a result, the load acts on the rolling bearing 87 only when the moment load increases due to the increase in the belt tension, and the rolling bearing 87 acts as a support.
Specifically, when the amount of deformation of the outer ring 89 when the maximum tension is applied is 70 μm, the amount of the radial gap may be set to, for example, 50 μm.

A rolling bearing 91 such as a cylindrical roller bearing and an oil seal 92 are interposed between the inner periphery of the distal end of the first hub 77 and the outer periphery of the rotating shaft 71. In addition, the variable diameter pulley is provided with a sliding bearing 9 on the peripheral surface of the first hub 77.
The first pulley main body 94 is movably supported in the axial direction via the third pulley 3, and the second pulley is movably supported in the axial direction by a boss 95 of the first pulley main body 94 via a slide bearing 96. A main body 97 is provided. Opposite surfaces of the pair of pulley bodies 94 and 97 are tapered power transmission surfaces 4,
5 are formed. A power transmission ring 6 having a substantially trapezoidal cross section is formed by the pair of power transmission surfaces 4 and 5.
Are eccentrically held with respect to the axis K of the pair of pulley bodies 94 and 97. When the power transmission ring 6 is eccentric, the two pulley main bodies 94 and 97 are separated from each other by an equal distance. A power transmission surface 8 to the belt 7 is formed on the outer peripheral surface of the power transmission ring 6, and the power transmission ring 8
Is wrapped around. A circumferential groove that meshes with the rib of the belt 7 is formed on the transmission surface 8.

A cylindrical portion 98 extending in the axial direction from the outer periphery of the first pulley main body 94 is fitted on the outer peripheral surface of the annular plate portion 78 of the connecting member 76, and the space therebetween is sealed by an O-ring 99. On the other hand, a pair of O-rings 100 is interposed between the outer peripheral surface of the boss 95 of the first pulley main body 94 and the inner peripheral surface of the boss of the second pulley main body 97 opposed thereto. Similarly, a cylindrical portion 101 extending in the axial direction from the outer periphery of the second pulley main body 97 is fitted on the outer peripheral surface of an end face plate 81 as a connecting member, and the space therebetween is sealed by an O-ring 102. As a result, a sealing space for accommodating and protecting the first and second diaphragm springs 11 and 12 is defined by the connecting members 76 including the respective pulley main bodies 94 and 97 and the end face plate 81. Each of the sealed spaces is filled with a lubricant, and each of the sliding bearings 93,
96 contribute to lubrication.

A plurality of variable-diameter pulleys are stacked as a pair of biasing means for biasing each of the pair of pulley bodies 94 and 97 in a direction approaching each other. , 12 are provided. These diaphragm springs 11, 1
The two have the same spring characteristics. Each of the diaphragm springs 11 and 12 has an outer diameter portion engaged with a corresponding pulley main body 94 and 97 so as to be capable of transmitting torque.
The inner diameter portion is engaged with the connecting member 76 (including the end face plate 81) so that torque can be transmitted.

Each of the diaphragm springs 11 and 12 has the same configuration as that of the embodiment shown in FIG. In the plurality of connection grooves of the inner diameter portion 61 of the first diaphragm spring 11,
While a plurality of plate-shaped connection protrusions 57 formed radially are fitted into the annular plate portion 78 of the connection member 76, respectively.
A plurality of connecting projections 58 formed on the outer peripheral edge of the first pulley main body 94 so as to protrude circumferentially are fitted in the connecting grooves of the outer diameter portion 62 of the first diaphragm spring 11, respectively. Also, the second diaphragm spring 12
A plurality of plate-shaped connection protrusions 59 radially formed on the end face plate 81 fixed to the connection member 76 are respectively fitted in the plurality of connection grooves of the inner diameter portion 61 of the second diaphragm spring 12. A plurality of connection protrusions 60 formed on the outer peripheral edge of the second pulley main body 97 so as to protrude circumferentially at regular intervals are fitted into the connection grooves of the outer diameter portion 62.

Thus, each of the diaphragm springs 1
1, 12, connecting member 76 and both pulley main bodies 94, 97
Rotate together. That is, the torque transmitted to the power transmission ring 8 via the belt 7 is applied to both pulley main bodies 94,
97, the diaphragm springs 11 and 12 and the connecting member 76 are transmitted to the rotating shaft 71. Further, the tension adjusting mechanism (not shown) adjusts the tension of the belt 7, so that the power transmission ring 6 is eccentric and the effective diameter D of the belt 7 can be changed.

Each of the diaphragm springs 11 and 12 is
Since the spring constants are set to be equal to each other, the inner diameter portion and the outer diameter portion can be displaced (bent in the axial direction) by the same amount in opposite directions. Therefore, when the power transmission ring 6 is eccentric, the center position in the axial direction between the pulley main bodies 94 and 97 can always be kept constant. As a result, the position of the width center L of the belt 7 can be kept substantially constant. it can.

Also in the embodiment of FIG. 13, the same operation and effect as those of the embodiment of FIG. 1 can be obtained, and high durability can be realized even if the diaphragm springs 11 and 12 are small. An excellent variable diameter pulley can be obtained.

[0054]

According to the first aspect of the present invention, since the diaphragm spring is interposed between each pulley main body and the connecting means, the transmission torque can be shared by the two diaphragm springs. As a result, the stress of each diaphragm spring is reduced. Can be reduced. Moreover, since there is no risk of stress concentration as in the case of supporting a single diaphragm spring by drilling, high durability can be achieved even if the diaphragm spring is small, so that a variable diameter pulley having a small size and excellent durability can be obtained. .

Further, by making the urging forces of both diaphragm springs equal, the axial displacements of both pulleys can be made substantially equal. Therefore, it is not necessary to use a torque cam mechanism in order to maintain the center of the width of the belt constant, and a smooth gear shift can be achieved with a simple structure. According to the second aspect of the present invention, since the connecting projection on the outer diameter portion of the diaphragm spring contributes only to the torque transmission, high stress is not generated in the connecting projection, so that the durability of the diaphragm spring is improved.

According to the third aspect of the present invention, since the tapered engagement portion included in the inclined surface on the rotation direction side of the connection protrusion smoothly continues to the outer diameter portion between the connection protrusions, stress concentration can be reduced. Further, at the time of torque transmission, the tapered portion of the inclined surface on the rotation direction side of each connection projection is pushed toward the center of the diaphragm spring, so that the diaphragm spring does not rattle and is aligned with the pulley main body.

According to the fourth aspect of the present invention, at least a part of the axially arranged range of the portion supporting the inner periphery of each pulley main body can be overlapped, so that the shaft supporting the inner periphery of each pulley main body can be overlapped. The length in the direction can be made sufficiently long, and as a result, each pulley main body can be stably supported without increasing the overall size. According to the fifth aspect of the present invention, since the seal member is provided double, when the present variable diameter pulley is applied to an automobile, muddy water can be prevented from entering between the sliding bearing and the power transmission surface. As a result, it is possible to prevent the sliding resistance of the pulley main body from increasing due to the intrusion of muddy water, and prevent the power transmission ring from slipping. In particular, since the muddy water that has entered between the seal members can be released to the outside through the escape hole by centrifugal force during rotation, the possibility of muddy water intrusion can be significantly reduced.

According to the sixth aspect of the present invention, since a plurality of disc springs having different spring performances are combined, a desired desired spring performance can be obtained as a whole, and the driving force transmission system including the variable diameter pulley can be freely designed. The degree can be increased.

[Brief description of the drawings]

FIG. 1 is a sectional view of a variable diameter pulley according to a first embodiment of the present invention, showing a state where a power transmission ring is concentric with a pulley main body.

FIG. 2A is a front view of a diaphragm spring, and FIG. 2B is a cross-sectional view taken along line AA of FIG. 2A.

3A is a front view of a receiving member that receives an outer diameter portion of a diaphragm spring, and FIG. 3B is a front view of FIG.
It is sectional drawing which follows the BB line of (a).

FIG. 4 is a partially cutaway perspective view of a main part of a receiving member.

FIG. 5 is an enlarged view of a main part of an outer diameter portion of a receiving member and a diaphragm spring.

FIG. 6 is an enlarged sectional view taken along line CC of FIG. 5;

FIG. 7 is a sectional view of the variable diameter pulley when the power transmission ring is eccentric.

FIGS. 8A and 8B are front views of a diaphragm spring and a receiving member according to a second embodiment of the present invention.

FIG. 9 is a cross-sectional view corresponding to FIG. 6 of a third embodiment of the present invention.

FIG. 10 shows the spring characteristics of the diaphragm spring shown in FIG.

FIG. 11 is an enlarged sectional view of a main part according to a fourth embodiment of the present invention.

FIG. 12 is a schematic diagram showing a power transmission ring and a stabilizer according to a fifth embodiment of the present invention.

FIG. 13 is a sectional view of a variable diameter pulley according to a sixth embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rotary shaft 2 1st pulley main body 3 2nd pulley main body 4, 5 Power transmission surface 6 Power transmission ring 7 Belt 11 1st diaphragm spring 12 2nd diaphragm spring 13 Connecting member 17 Receiving member 20 Boss part (back surface) 26, 30 bush (sliding bearing) 32 connecting portion 33 pressing plate portion 34 connecting protrusion 35 main portion 36 receiving plate 37 connecting groove 39 groove bottom portion 40 corner portion 41 back surface 42 connecting protrusion 43 first disc spring 44 Second disc spring 45 First O-ring 46 Second O-ring 47 Escape hole 61 Inner diameter part 62 Outer diameter part 63 Connection groove 64, 66 Connection protrusion 65, 68 Edge 67 Top part 68, 70 Engagement part 71 Rotating shaft 76 Connecting member 81 End face plate 94 First pulley main body 97 Second pulley main body

Claims (6)

[Claims] 1. A variable diameter pulley capable of changing an effective diameter with respect to a belt, comprising: a first and a second annular pulleys which are rotatable around a rotation axis and relatively movable in an axial direction relative to each other. A pair of tapered power transmission surfaces respectively formed on opposing surfaces of these pulley main bodies; and a pair of power transmission surfaces sandwiched eccentrically with respect to the axis of both pulley main bodies, and an outer peripheral surface. A power transmission ring around which a belt is wound, biasing means for biasing both pulley bodies in a direction approaching each other, and connecting means for connecting the biasing means and the rotating shaft so as to be integrally rotatable, The biasing means includes first and second diaphragm springs, and the inner diameter portion or the outer diameter portion of each diaphragm spring is restricted in axial movement with respect to the corresponding pulley main body. A variable diameter, wherein the outer diameter portion or the inner diameter portion of each diaphragm spring is integrally rotatably engaged with the connecting means in a state where the movement in the axial direction is restricted. Pulley. 2. An outer diameter portion of each diaphragm spring is formed with a plurality of connecting protrusions for engaging with a plurality of connecting grooves of a corresponding member, respectively, which are circumferentially equally arranged, and each of the connecting protrusions transmits torque. In order to contribute only to this, the radial edge of the connection protrusion and the groove bottom of the connection groove are not in contact with each other, so that an axial load is received by the outer diameter portion between adjacent connection protrusions of each diaphragm spring. The variable diameter pulley according to claim 1, wherein 3. An outer diameter portion of each diaphragm spring is formed with a plurality of angular transmission protrusions for torque transmission which are respectively engaged with a plurality of connection grooves of a corresponding member and are circumferentially equally projecting. At least the inclined surface on the rotation direction side of the projection includes a tapered engagement portion that smoothly continues to an outer diameter portion between the connection projections, and a connection groove corresponding to each connection projection has a tapered engagement portion that matches the engagement portion. The variable diameter pulley according to claim 1, further comprising a joining portion. 4. The first pulley main body includes a portion extending axially through the second pulley main body and extending to the rear side of a power transmission surface of the second pulley main body. The variable diameter pulley according to claim 1, 2, or 3, wherein a peripheral portion is received by a portion extending to the rear side via a slide bearing. 5. A pair of seal members held by the main body of the second pulley between the inner peripheral portion of the main body of the second pulley and the portion extending to the rear side, the rear side of the sliding bearing. Are arranged side by side on the tip side of the portion extending toward the sliding bearing, the interference of the seal member on the side closer to the slide bearing is set to be larger than the interference of the seal member on the side far from the slide bearing, and the second pulley main body is 5. A relief hole between the inner peripheral portion and the portion extending to the rear side, the relief hole communicating an intermediate region between the pair of seal members to the outside. The variable diameter pulley according to any one of the above. 6. The variable diameter pulley according to claim 1, wherein each diaphragm spring is formed by stacking a plurality of disc springs having different spring characteristics.