DE102009030991A1 - Shiftable free-wheel device for use in crank continuously variable transmission of vehicle, has spring contact that is arranged at cage and works together with clamping bodies, where clamping bodies are arranged in cage - Google Patents

Abstract

The device has a contoured inner shaft, where a free-wheel unit is shiftable in multiple switching positions against the shaft. Multiple clamping bodies i.e. rollers, are arranged in a cage. A switching device i.e. shifter rod, is provided for the free-wheel unit and rotatably arranged in the cage. A spring contact (61) is arranged at the cage and works together with the clamping bodies. The contact is provided as a spring contact ring that encloses the cage and radially outwardly encloses the bodies. The spring contact has recesses (62) for receiving projections formed in the cage.

Description

The The invention relates to a switchable freewheel device, in particular for use in a crank CVT transmission, and a crank CVT transmission with such a switchable freewheel device.

A crank-CVT transmission is for example from the DE 102 43 533 A1 known. In this transmission, an adjustable eccentric drive arrangement with eccentric components is provided on an input shaft which can be driven by a motor and which forms a driving shaft with respect to the transmission, which is connected via connecting rod-like connecting elements to a driven shaft which, with respect to the transmission, has an output shaft. or output shaft forms. The driven shaft is driven by the transmission of the stroke of the connecting elements by means of freewheel devices on the shaft, which are provided between the connecting rod-like connecting elements and this shaft. The driving crankshaft and the output shaft are aligned parallel to each other and rotatably mounted in a housing. Torque is introduced into the crankshaft from an internal combustion engine and transmitted to the output shaft through the crank CVT transmission. Depending on the position of the Exzenterbauteile with respect to the axis of rotation of the drive shaft, the eccentricity of the Exzenterbauteile and thus their axis of rotation relative to the output shaft is changed, whereby the transmitted from the connecting rod connecting elements on the output shaft hub and thus the ratio of the transmission can be adjusted. On the output shaft, the torque can be tapped for example for driving wheels of a vehicle.

In usually in a crank-CVT transmission in the axial direction of the Crankshaft arranged one behind the other several eccentric units, each having connecting rod-like connecting elements, which with a corresponding number of freewheel units on the output side of the transmission.

The Freewheel units can be considered non-switchable or reversible Freewheeling be provided. In the former case is in a Relative rotation direction of an outer ring of a freewheel unit and the output shaft achieved a blocking effect and in the other Relative rotation direction no blocking effect achieved. With reversible Freewheeling two locking positions are provided, in where the two components in a first and a second direction of relative rotation Block and thus in the first and second direction of rotation together to be twisted. Because of the direction of rotation of the output shaft be changed, so that by means of the switchable freewheels, for example a reverse gear can be realized.

A switchable freewheel device is in the WO 03/026911 described. The outer periphery of the output shaft has a polygonal-like profile and is formed such that the areas forming the polygonal profile are symmetrical with respect to the overrunning function of the freewheel realized by means of sprags located between the polygonal profile and an outer ring are formed. To switch the blocking function of the freewheel a switching device is provided which has a plurality of switching units, which are each arranged between adjacent clamping bodies. The switching units are synchronously actuated and have switching means, each with a rotatable disc-shaped area and a profiled bar consisting of a profiled area. At this profiled area, a spring is provided which can apply a clamping body in the corresponding locking direction by means of a leg of the spring. The spring element and the profiled regions are arranged eccentrically with respect to the axis of rotation of the disk-shaped region, so that upon rotation of the disk-shaped region a circumferential displacement of the spring elements and the profiled regions takes place. By rotation of the disk-shaped areas, for example about 180 °, changes the direction of tension or force direction of the spring element or the spring leg with respect to the clamping body. The suspension is designed separately for each clamping body. A common twisting device extending axially through all the free-wheeling units may be provided.

From that It is an object of the invention, a switchable freewheel device provide that is compact and requires few individual components.

These Task is with a switchable freewheel device with the features of claim 1. Preferred embodiments are specified in the dependent claims. A crank CVT transmission with a switchable freewheel device is specified in claim 16.

The invention is based on the idea to integrate the springing of the clamping body in a cage for the clamping body, wherein at the same time the switching device cooperates with the cage for switching the gear or between free-running position, common rotation in one direction or common rotation in the other direction and so switching the clamp body to achieve different positions of the clamp body with respect to the profiled inner shaft and thus different locking and freewheeling Rich plans.

To contains the switchable freewheel device in particular a profiled inner shaft, for example with a polygonal Profile, which is preferably designed such that the this profile forming surfaces in relation to the blocking function or free-running function the freewheel units are formed symmetrically. Next is one Freewheel unit provided opposite to the inner shaft is adjustable in several switching positions and several in one Cage arranged clamping body to achieve the Locking and freewheeling directions. A switching device for the freewheel device is arranged rotatably with the cage, so that by actuating the switching device, in particular Turning the switching device, the position of the clamp body changed the respective polygonal surfaces of the inner shaft can be and thus the different positions to the transmission circuit can be provided. At the cage is at the same time one together for the clamp body acting springing arranged so that through the cage and the effected Springing all sprags together simultaneously springing become. This can offset the number of components Significantly reduced the prior art described in the introduction In particular, there are no single switching devices and Anfederungselemente for each of the clamp body must be provided.

The Springing is preferable as the cage and the one in it arranged clamping body radially outside encompassing Suspension ring provided. This forms a compact design the common springing for those in the cage arranged clamping body.

Preferably are for positioning the Anfederungsrings on the cage projections provided with corresponding recesses on the Anfederungsring for fixing the rotational position of the Anfederungsrings opposite the cage are engaged. Alternatively, it goes without saying possible, on the cage, the recesses and corresponding Provide projections on the Anfederungsring or other positioning and fasteners to use. This ensures in a simple way, a rotation of the Anfederungsrings and of the cage to each other.

Preferably is an additional sprag suspension in Circumferential direction for each of the clamp body on the Anfederungsring intended. This Klemmkörperanfederung can in example by in each case one of the radial directions acting lobe-like springs be provided. Preferably, for each clamp body in each of the circumferential directions a Klemmkörperanfederung provided.

The Clamping bodies are preferably rollers. Roller clutches are robust and reliable.

Preferably is the switching device by a relative to the inner shaft rotatable with respect to the circumferential position to the inner shaft Shift linkage with the or the freewheel units is engaged, provided. The shift linkage is included usually rotatable along a peripheral portion of the inner shaft, namely, as far as the desired switching positions by moving the clamp body on the polygonal To be able to adjust surfaces of the profiled inner shaft. If the shift linkage by a suitable mechanism twisted with respect to the inner shaft, so twisted due the engagement of the switching device with the cage, the are arranged rotationally fixed to each other, the cage with the provided therein clamping bodies with respect to Inner shaft.

The Shift linkage may according to a preferred embodiment by a rotatably connected to the cage shift rod and a switching ring formed with respect to the shift rod is fixed. The switching ring is rotatable in a groove of the inner shaft and held axially stationary. The shift rod is in one provided for this purpose, in the axial direction of the Inner shaft extends and has a width that fits with the cage engaging the shift rod to the predetermined Circumferential range for setting the switching positions are rotated can.

Preferably is on the shift rod connected to this position-fixed Engagement slide provided in a contoured shift groove the switching device is engaged, wherein the contouring the Switching positions corresponds and preferably both by a contouring is achieved in the longitudinal and in the circumferential direction. So may vary depending on the position of a or axial direction displaceable switching element a circumferential position be set of the shift linkage. For example the shift groove unevenly S-shaped designed, with the various switching positions at the vertices of the S and at start and end points of the groove are formed.

Preferably, on the switching device further in the inner shaft rotatably but axially displaceable inner slide is provided, which is formed in a cavity of the inner shaft. To prevent rotation, for example, the inner shaft and the inner slide each have a tooth profile or tongue and groove profile, which are engaged with each other. By the inner slider and the inner shaft, a hydraulic space in the inner shaft is preferably defined, in the hydraulic fluid is such and can be discharged, that the axial position of the inner slider relative to the inner shaft is variable. Instead of Ver Use of hydraulic fluid and a hydraulic device is for moving the inner slide and a mechanical actuation, such as traction cables, conceivable.

Preferably is the contoured shift groove formed in the inner slider, so that by a displacement of the inner slide in the axial direction relative to the to the inner shaft axially fixed Eingriffsgleitelementen of Shift linkage a rotation of the shift linkage is caused, in turn, the clamping body of the freewheel units leads into the different switching positions.

Preferably is when using a hydraulic device for adjusting the Internal slide against the inner shaft of the inner slide through a spring means biased in the axial direction, so that in with Hydraulic fluid non-pressurized state of the inner slide and the inner shaft occupy a defined axial position relative to one another, for example, a neutral shift position or the like equivalent. The spring device for preloading the inner slide in an axial direction can also be correspondingly with mechanical adjusting means of the inner slide are used.

Preferably are several provided in the axial direction of the inner shaft one behind the other Freewheel units provided by a common switching device, z. As common shift rails are adjusted.

following the invention will be described by way of example with reference to the attached Figures described in which:

1 shows in perspective view a switchable freewheel device;

2 shows a perspective view of an assembly of inner shaft and switching device, wherein the inner shaft is cut in a peripheral portion;

3 a longitudinal sectional view through the assembly according to 2 is;

4 a perspective, partially broken away view of the assembly according to 2 and 3 used inside slide is;

5 a perspective view of the inner slider is;

6 is a perspective view of the shift linkage;

7 is a perspective view of the inner shaft;

8th is a cutaway view in the longitudinal direction of the inner shaft;

9 shows an assembly of inner slide and shift linkage;

10 is a view of a freewheel unit;

11 in a perspective view of the cage of the freewheel unit 10 shows;

12 in a perspective view of the Anfederungsring the freewheel unit 10 shows;

13 in a perspective view, partially broken away, is an overall view of the switchable freewheel device; and

14 a schematic diagram to illustrate the operation of the switchable freewheel device is.

The switchable freewheel device 100 in perspective view in 1 is shown, contains an inner shaft 3 that, as in 2 can be seen, at its periphery a plurality of identically formed polygonal profiles or polygonal profiles 41 having. The polygon profiles 41 are arranged one behind the other in the axial direction, two groups each having three polygonal profiles 41 are provided. On the inner shaft 3 , in particular the polygonal profiles, are free-wheeling units 1 placed. At the in 1 shown embodiment, a total of six freewheel units 1 provided in the axial direction one behind the other in two groups of three freewheel units 1 are provided. As needed, more or fewer freewheel units 1 and a corresponding number of polygon profiles 41 be provided.

In addition, the switchable freewheel device contains 100 a switching device 2 for the freewheel units 1 , wherein by the switching device 2 all freewheel units 1 can be operated together and can be brought into different switching positions. Different shift positions means that the freewheel units 1 opposite the profiled inner shaft 3 can be rotated so that the inner shaft 3 with the freewheel units 1 can be rotated together in a first direction of rotation or a second direction of rotation or a freewheeling position is provided, in which no blockage between the inner shaft 3 and the freewheel units 1 is provided and thus the freewheel units 1 relative to the inner shaft 3 to make the freewheel function.

As in 2 is recognizable, is the inner shaft 3 hollow design. The cavity of the inner shaft 3 is with a lid 5 that is fixed to the inner shaft 3 connected, closed on one side. At the opposite end of the inner shaft 3 is a piston rod 7 used a hydraulic cylinder, which also firmly, both in the axial and rotational direction, with the inner shaft 3 is connected, whereby a closed cavity is defined. In this cavity is an inner slide 6 arranged in the inner shaft 3 rotatably mounted but axially displaceable. A variable in its size hydraulic chamber 9 is in the inner shaft 3 through the piston rod 7 of the hydraulic cylinder and the inner slide 6 shaped. In the hydraulic room 9 can be fed by supply and discharge hydraulic fluid and so its size can be changed. The inner slider 6 is by a spring 4 in an axial direction (to the right in FIG 3 ), so that without supply of hydraulic fluid to the hydraulic chamber 9 the inner slide 6 with respect to the inner shaft 3 is in an axially defined position. To the inside slide 6 axially displaceable but non-rotatable in the inner shaft 3 to store is how 4 respectively. 8th is removable, the inner shaft with a toothing 44 and the inner slider 6 with a corresponding external toothing 22 Mistake. The inner slider 6 also has a one-sided guide surface 20 for the spring 4 (please refer 4 ), due to the fact that the spring 4 is designed in the illustrated embodiment as a torsion coil spring, is essentially formed by an inner cylinder, which at the same axial end of the inner slide 6 is provided as the external teeth 22 , At the opposite axial end of the inner slide 6 is a guide surface 21 for the hydraulic cylinder 7 shaped so that the inner slider 6 along the guide surface 21 of the hydraulic cylinder 7 when changing the volume of the hydraulic space 9 can slide.

The supply means for supplying and discharging hydraulic fluid into the hydraulic chamber 9 For example, by a connecting line in the inner slide 7 be formed.

How best 5 is removable, is inside slide 6 in the cylinder surface a shift groove 23 formed, which is relative to the axial direction and circumferential direction of the inner slider 6 or the inner shaft 3 each contoured extends. In particular, the shift groove 23 , such as off 5 can be removed, an S-like shape, so that in their end positions in each case a switching position and at the vertices of the S also each a switching position is defined.

On the inner shaft 3 is like 7 is removed, further an annular groove 45 and an axially extending groove 43 , in each case no polygonal profile 41 is designed with a star-shaped contour provided. In the ring groove 45 and in the axially extending groove 43 preferably twice along the circumference of the inner shaft 3 is formed, a shift linkage 8th , in particular a switching ring 34 and shift rails 31 be used. This in 6 shown in detail switching linkage 8th is from the switching ring 34 and the fixed connecting rods 31 formed, with the shift rails 31 diametrically opposite each other at the switching ring 34 through fastening units 32 are firmly attached. The shift linkage 8th also has switching roles 33 on that at the crossings between shift rod 31 and switching ring 34 are provided and through the fastening units 32 attached to it. As in 9 shown, the switching rollers 33 in the shift groove 23 of the inner slide 6 intervention. Due to that the annular groove 45 on the inner shaft 3 is provided, the shift linkage 8th opposite the inner shaft 3 axially fixed. As 9 is removable, but is due to the displaceability in the axial direction of the inner slide 6 opposite the inner shaft 3 and the leadership of the scooters 33 in the shift groove 23 the inner slider 6 opposite the shift linkage 8th axially displaceable and is the shift linkage 8th opposite the inner shaft 3 and opposite the inner slider 6 due to the contouring of the shift groove 23 as far as the contouring of the shift groove 23 allows, rotatable.

Further, the shift rails 31 in engagement with recesses or grooves 54 for the shift rails 31 on the cage 51 of the roller freewheel are provided (see 10 to 12 ). When pivoting or twisting the shift linkage 8th with respect to the inner shaft 3 thus become the cages 51 moved along and move along the circumferential direction of the inner shaft 3 ,

The ring groove 45 on the inner shaft 3 is between each three adjacent to each other in the axial direction provided polygonal profiles 41 provided so that in each case three adjacent freewheel units 1 can be provided on the respective polygonal profiles.

The more accurate in 10 to 12 Freewheels are shown as roller freewheels with rollers 52 designed as sprags. The roles 52 are in a cage 51 used, which at each of its two axially terminating ring elements noses 55 for receiving a springing 61 having. The springing 61 ( 12 ) is with correspondingly shaped recesses 62 provided so that the springing 61 opposite the cage 51 is held against rotation and stationary. The cage 51 and the springing 61 each have a plurality of recesses into which the rollers 52 can be used as a clamping body. At the cage 51 are also projections 53 intended for roll positioning. At the together with the cage 51 held springing 61 corresponding recesses are provided so that the rollers can protrude through them.

The springing 61 also has roller springs 63 on, at the two edges in the circumferential direction of the respective recesses for the rollers 52 are provided. The roller suspensions 63 are designed as soft spring tabs and ensure a defined position of the rollers used as a clamping body 52 , Thus, the Gesamtanfederung the freewheel rollers 52 through the roller suspension 63 and the spring 61 , The roller suspensions 63 could alternatively be performed as, for example, folded spring or separate part. By the springing 61 Thus, a suspension and damping of the rollers 52 achieved as a clamping body.

In 13 the overall arrangement is shown, with outer rings 71 the freewheel unit are partially cut open.

With the freewheel unit shown in the figures can four different switching stages (range P (to insert a Parking lock), N as neutral, both without blocking effect, as well as the areas R and D, each with a counter-blocking effect for one Forward and one reverse) achieved become.

To switch the individual gears, the roller clamp bodies must 52 in certain areas in the gap between polygon profile 41 and outer ring 71 be brought to the freewheel. This is done by means of a hydraulic device in the hydraulic chamber 9 that is between the inner shaft 3 , the inner slider 6 and the piston rod 7 is formed, hydraulic fluid added or removed. A defined volume of hydraulic fluid introduced determines the axial position of the inner slider 6 opposite the inner shaft 3 , Because the groove 23 of the inner slide 6 about the roles 33 of the shift linkage 8th is engaged, can thus be achieved that the switching rollers 33 in a desired switching position corresponding position in the shift groove 23 arrive (see 5 ).

As 14 can be removed, correspond to the switching positions defined positions of the rollers 52 on one of the polygonal surfaces of the inner shaft 3 ,

When hydraulic fluid in the hydraulic chamber 9 is introduced, thus shifts the inner slide 6 a defined distance in the axial direction against the force of the spring 4 , This will be the shift linkage 8th including the switching rollers 33 in the shift groove 23 guided shifted and leads to a rotation of the shift linkage 8th opposite the inner shaft 3 because the shift linkage 8th in the axial direction of the inner shaft 3 is fixed. Together with the shift linkage 8th become the cages 51 the freewheel units 1 moved, ie with respect to the inner shaft 3 twisted. This will be the roles 52 into the desired positions on the polygon profile 41 brought so that in the areas D and R by the Anfederungen 61 and roll springs 63 a blocking effect is generated (in each case in opposite directions) and in the other areas (P and N) no blocking effect by the rollers 52 is generated as a clamping body.

Instead of the four provided in the present embodiment Switching ranges could also be the freewheel device, for example be realized with only two switching ranges or three switching ranges.

1

Freewheel unit

2

switching device

3

inner shaft

4

feather

5

cover

6

interior slide

7

piston rod

8th

shift linkage

9

hydraulic chamber

20

guide surface

21

guide surface

22

external teeth

23

switching groove

31

shift rod

32

fixing unit

33

switching role

34

switching ring

41

polygonal profile

43

groove

44

gearing

45

ring groove

51

Cage

52

Role clamp body

53

head Start

54

groove

55

nose

61

springing

62

recess

63

Rollenanfederung

71

outer ring

100

Freewheel device

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - DE 10243533 A1 [0002]
• WO 03/026911 [0005]

Claims (16)

Switchable freewheel device ( 100 ), comprising a profiled inner shaft ( 3 ), at least one opposite the inner shaft ( 3 ) in several switching positions adjustable freewheel unit ( 1 ) with several in a cage ( 51 ) arranged sprags ( 52 ), and a switching device ( 2 ) for the freewheel unit ( 1 ), wherein the switching device ( 2 ) with the cage ( 51 ) is arranged rotationally fixed and on the cage ( 51 ) a common for the clamping body ( 52 ) acting springing ( 61 ) is arranged. Freewheel device ( 100 ) according to claim 1, characterized in that the springing as the cage ( 51 ) and the clamping bodies ( 52 ) Radial encircling Anfederungsring ( 61 ) is provided. Freewheel device ( 100 ) according to claim 2, characterized in that on the cage ( 51 ) Projections ( 55 ) provided with corresponding recesses ( 62 ) on the Anfederungsring ( 61 ) for determining the rotational position of the Anfederungsrings ( 61 ) opposite the cage ( 51 ) are in intervention. Freewheel device ( 100 ) according to claim 2 or 3, characterized in that the Anfederungsring ( 61 ) for each of the clamp bodies ( 52 ) a sprag suspension ( 63 ) is provided in the circumferential direction. Freewheel device ( 100 ) according to claim 4, characterized in that for each clamping body ( 52 ) a sprag suspension ( 63 ) is provided in each circumferential direction. Freewheel device ( 100 ) according to claim 4 or 5, characterized in that the Klemmkörperanfederung ( 63 ) is designed as a spring flap. Freewheel device ( 100 ) according to one of the preceding claims, characterized in that the clamping body ( 52 ) Are roles. Freewheel device ( 100 ) according to one of the preceding claims, characterized in that the switching device ( 2 ) one opposite the inner shaft ( 3 ) with respect to its circumferential position to the inner shaft ( 3 ) at least over a peripheral portion rotatable shift linkage ( 8th ), which with the freewheel unit ( 1 ) is engaged. Freewheel device ( 100 ) according to claim 8, characterized in that the shift linkage ( 8th ) one with the cage ( 51 ) rotatably connected shift rod ( 31 ) and the shift rod ( 31 ) fixed in position with a switching ring ( 34 ) connected in a groove ( 45 ) of the inner shaft ( 3 ) rotatable and axially stationary is held. Freewheel device ( 100 ) according to claim 8 or 9, characterized in that on the shift linkage ( 8th ) an engagement slide element ( 33 ) is provided, which in a corresponding to the switching positions in the longitudinal and circumferential direction of the inner shaft ( 3 ) contoured shift groove ( 23 ) of the switching device ( 2 ) is engaged. Freewheel device ( 100 ) according to one of the preceding claims, characterized in that the switching device ( 2 ) one in the inner shaft ( 3 ) rotatably, but axially displaceable inner slide ( 6 ) having. Freewheel device ( 100 ) according to claim 11, characterized in that the inner slide ( 6 ) and the inner shaft ( 3 ) a hydraulic space ( 9 ) in the inner shaft ( 3 ) in which hydraulic fluid can be supplied and discharged in such a way that the axial position of the inner slide ( 6 ) against the inner shaft ( 3 ) is changeable. Freewheel device ( 100 ) according to claim 11 or 12, characterized in that the inner slide ( 6 ) by a spring device ( 4 ) in an axial direction for defining the hydraulic space ( 9 ) is preloaded. Freewheel device ( 100 ) according to claim 11, 12 or 13, characterized in that the switching groove ( 23 ) according to claim 10 in the inner slide ( 6 ) is provided. Freewheel device ( 100 ) according to one of the preceding claims, characterized in that several, by the switching device ( 2 ) jointly switchable freewheel units ( 1 ) in the axial direction of the inner shaft ( 3 ) are provided one behind the other. Crank CVT transmission ( 100 ) with a freewheel device according to one of the preceding claims.