DE102017107691A1 - One-way clutch and gearbox with the one-way clutch - Google Patents

Abstract

One-way clutches - also called one-way clutch (OWC) in English - make it possible to set or uncouple two coupling partners in dependence of the relative movement to each other. A one-way clutch 1 having a first ring 2 and a second ring 4 is proposed. with a plurality of clamping bodies 7, wherein the clamping bodies 7 are arranged in an annular gap 6 between the first and the second ring 2,4, wherein one of the rings 2 is designed as a ramp ring 9 and has a plurality of ramp areas 10 extending in the circumferential direction, wherein the clamping bodies 7 are arranged in the ramp areas 10, wherein the ramp areas 10 have a free portion 11 and a clamping portion 12, wherein the one-way clutch 1 is in a freewheeling state, when the clamping bodies 7 are arranged in the free portion 11 and wherein the one-way clutch 1 in a Clamping state, when the clamping body 7 are arranged in the clamping portion 12, with a Mehrz Ahl of webs 14, wherein the webs 14 may form a start for the clamping body 7, wherein the webs 14 are rotatable relative to the ramp ring 9 in the direction of rotation, wherein in a freewheeling position, the webs 14 are each arranged between the clamping portion 12 and the clamping body 7 and in a clamping position, the webs 14 each release the clamping portion 12.

Description

The invention relates to a one-way clutch having a first ring and a second ring, with a plurality of clamping bodies, wherein the clamping bodies are arranged in an annular gap between the first and the second ring, wherein one of the rings is formed as a ramp ring and a plurality of wherein the clamp bodies are disposed in the ramp areas, the ramp areas having a free portion and a clamping portion, the one-way clutch being in a freewheeling state when the clamp bodies are disposed in the free portion and the one-way clutch is in a clamped state, when the clamping bodies are arranged in the clamping portion, and with a plurality of webs, wherein the webs can form a start-up for the clamping body. The invention also relates to a vehicle transmission with the one-way clutch.

One-way clutches - also called one-way clutch (OWC) in English - make it possible to set or decouple two coupling partners against rotation relative to one another.

The publication DE 10 2008 049 799 A1 , which forms probably the closest prior art, discloses a freewheel with sprags, which may be formed as pinch rollers, which are guided between an inner ring and a concentrically arranged outer ring by means of cage elements, which are made integral with the inner ring, wherein the Springs loaded by springs in the circumferential direction and are arranged in spaces that are limited by a respective clamping ramp, the clamping ramps are integrally formed on the inner ring and the cage elements are formed as cage webs.

In a freewheeling state, the inner ring and the outer ring can rotate uncoupled from each other. In a clamping state, the clamping bodies run along the clamping ramps and clamp the inner ring relative to the outer ring. If the torque to be transmitted in the clamping state is too great, the clamping bodies continue to run along the clamping ramps until an equilibrium of forces is reached or, in the event of an overload, deformation of the clamping ramps can occur.

The document proposes this technical background DE 10 2015 209 309 A1 before, that a region of the clamping ramps has an increased clamping angle, which is selected so that when an overload occurs slipping of a clamping body is possible. Thus, a first clamping ramp region with a first clamping angle serves to clamp the inner ring relative to the outer ring via the clamping body. A second, subsequent clamping ramp area, which has a larger clamping angle, serves to allow the overload occurring slippage of the clamping body.

It is an object of the present invention to provide a one-way clutch having improved functionality. This invention is achieved by a one-way clutch having the features of claim 1 and by a vehicle transmission having the features of claim 10. Preferred or advantageous embodiments of the invention will become apparent from the dependent claims, the following description and / or the accompanying figures.

The invention relates to a one-way clutch, which is suitable and / or designed in particular for the selective and / or temporary coupling of two coupling partners. The one-way clutch can also be referred to as a freewheel. For example, the one-way clutch can be used in a vehicle transmission for decoupling from an engine, in particular from an internal combustion engine.

The one-way clutch has a first ring and a second ring. The rings may be formed as separate components, alternatively, these are formed as sections of larger components. For example, one of the rings or both rings may be formed as a portion of a shaft or axle or surrounding structure. The rings are coaxial and concentric with each other. Between the rings an annular gap is at least partially formed in the direction of rotation.

The one-way clutch has a plurality of clamping bodies, wherein the clamping bodies are preferably arranged regularly spaced from one another in the annular gap and / or between the first and the second ring.

One of the rings is formed as a ramp ring and has a plurality of ramp areas extending in the direction of rotation. The clamp bodies are arranged in the ramp areas. The ramp areas change in the course in the circumferential direction of the free width in the radial direction of the annular gap. The ramp areas each have a free section and, in a clamping direction, starting from the free section, a clamping section. In the free portion, the free width of the annular gap is greater than in the clamping portion.

The one-way clutch is in a freewheeling state when the clamping body in the Free section are arranged. In contrast, the one-way clutch is in a clamping state when the clamping body are arranged in the clamping portion. In particular, the one-way clutch is in the clamping state when the clamping body are arranged in the clamping portion and at the same time clamp the first and the second ring. In particular, the free width of the annular gap in the clamping portion is smaller than the outer diameter of the respectively arranged therein clamping body.

The one-way clutch has a plurality of webs, wherein the webs can form a start-up for the clamping body. Preferably, each of the clamp body is associated with a web. The webs are particularly preferably arranged starting from the respective clamping body in the same direction of rotation as the clamping portion.

In the context of the invention it is proposed that the webs are rotatable relative to the ramp ring in the direction of rotation, in particular pivotable. Preferably, the webs in their entirety and / or as a substructure section are rotatable or pivotable together. The webs can be arranged in at least two positions: In a freewheeling position, the web is arranged in the circumferential direction in each case between the clamping portion and the clamping body. Thus, the clamping body can not reach the clamping portion when the web or the webs is in the freewheeling position or are. In a clamping position, the web is in each case arranged so that the clamping portion is released, so that the clamping body can reach the clamping portion. In particular, the one-way clutch can go into the clamping state.

It is a consideration of the invention to propose a one-way clutch which is formed as a switchable one-way clutch. By pivoting the webs relative to the ramp ring, the one-way clutch can be switched between a freewheeling state and a possible clamping state, so that the one-way clutch is formed as a switchable one-way clutch and has an extended functionality.

In a preferred embodiment of the invention, the web forms in the clamping position together with the clamping portion, in particular in each ramp area a common contact contour for the clamping body. The contact contour is designed in particular as an overload contour. The clamping body can enter into a double contact with the contact contour, wherein the clamping body contacts the clamping section and the web at the same time

In the event that the torque to be transmitted in the one-way clutch increases too much, it is to be feared without further measures that one of the rings is irreversibly deformed due to the excessive clamping force and thus damaged. In the prior art it has been proposed that the actual clamping region of the ramp section is adjoined by a further ramp region which has a different clamping angle than the actual clamping region. However, this training is difficult to implement production technology, since depending on the friction coefficient of the clamping angle should be up to 90 °. In the preferred embodiment it is provided that the switchable one-way clutch is designed so that the webs - if a possible clamping state to be set - are not completely moved out of the ramp area, but in a partial area, in particular in an end region, are arranged, so that the webs form the further ramp area. The use of the webs as a further ramp region has the advantage that the contact surface of the webs can be designed functionally and in particular independently of the contour of the ramp regions, in particular independently of the contour of the clamping section. Thus, the contact surfaces of the webs can be designed so that they can implement the overload function improved.

The mode of operation of the contact contour is that, when too large a torque, in particular an overload torque, is transmitted, the clamping body continues to run in the ramp region and in particular in the clamping section until it starts against the web. In this position, the torque to be transmitted and / or the clamping force to be transmitted is not only derived exclusively via the clamping section, but also in parallel thereto via the web. Thus, a clamping angle or an effective clamping angle increases abruptly with the contact of the clamping body with the contact contour. From reaching this position, the clamping body has two points of contact or contact areas with the contact contour. As the torque is further increased, an increasing part of the clamping force is transmitted via the contact point, which is located on the web and thus on the area of the contact contour with the increased clamping angle, whereby the effective clamping angle continues to change until it is opposite to the slipping of the clamping body the other ring is coming. As a result of this sliding movement, a further increase in the clamping force is avoided so that no plastic deformation of the components in the clamping contact can occur. The two rings are released when sliding the clamp body relative to each other. This behavior is also known as roll over. With this development it is achieved that the functionality of the one-way clutch is further improved.

With regard to the functionality is particularly preferred that the contact surface of the webs are each aligned in the radial direction and / or one Take the clamping angle to the respective clamping body of 90 °. This clamping angle implements the overload function as described above particularly effectively and can be realized in a particularly simple manner in terms of production technology since the webs can be designed independently of the ramp areas.

In a preferred structural realization of the invention, the plurality of webs, in particular all webs, formed by a cage ring. In particular, the plurality of webs, in particular all webs, connected to each other via a common side ring portion, wherein the cage ring is arranged coaxially with the first and the second ring. In principle, such a side ring portion can be arranged on each axial side of the webs. However, it is preferred if the side ring portion is arranged only on one axial side and the webs each have a free end portion on the other axial side. In particular, the cage ring is designed as a comb cage.

In a preferred constructive development of the invention, the one-way clutch has a spring device, wherein the spring device acts between the ramp ring and the cage ring, wherein the cage ring is biased relative to the ramp ring so that the cage ring is moved into the clamping position. In particular, the cage ring is loaded in the direction of the clamping position. This constructive development has the advantage that the one-way clutch is guided without further control of the cage ring in the clamping position, so that the one-way clutch occupies the clamping function as a safety function.

In a practice-oriented implementation, the one-way clutch may comprise an actuator for switching the cage ring from the clamping position to the freewheeling position and / or from the freewheeling position to the clamping position. The actuating member preferably extends in the axial direction, so that it does not form a disturbing contour for the relative movement between the rings.

In a preferred embodiment of the invention, the ramp ring is formed as an outer ring. Optionally additionally, the ramp ring has sliding sections for the inner ring, so that it-provided that the one-way clutch is not in the clamping state-can slide with little friction relative to the ramp ring formed as an outer ring. The clamping bodies are preferably designed as pinch rollers so that they can transmit the clamping force and / or the torque over a certain axial width. The roller axes of the clamping body, in particular of the pinch rollers are aligned parallel to a main axis of the one-way clutch.

In a preferred embodiment of the invention, the clamping section has no turning point in the course. This is made possible by the fact that the clamping section does not have to pass into an overload section, since this function is taken over by the webs. Alternatively or additionally, the course of the clamping section is formed continuously and / or differentiable.

Another object of the invention relates to a vehicle transmission in a drive train of the vehicle, wherein the vehicle transmission has the one-way clutch, as described above or according to one of the preceding claims. It is provided that at least temporarily a traction torque, in particular a main traction torque is transmitted via the one-way clutch.

• 1a, b eine schematische, seitliche Draufsicht auf eine Einwegkupplung als ein erstes Ausführungsbeispiel der Erfindung;
• 2a, b eine schematisierte, seitliche Draufsicht auf die Einwegkupplung in der 1 zur Beschreibung der Funktionsweise des Käfigrings der Einwegkupplung in den 1 a, b;
• 3 eine schematische dreidimensionale Darstellung eines Ausschnitts der Einwegkupplung der vorhergehenden Figuren;
• 4 eine weitere, schematische, dreidimensionale Darstellung eines weiteren Ausschnitts der Einwegkupplung der vorhergehenden Figuren.

Further features, advantages and effects of the invention will become apparent from the following description of a preferred embodiment of the invention and the accompanying figures. These show:

• 1a, b a schematic, side elevational view of a one-way clutch as a first embodiment of the invention;
• 2a, b a schematic, lateral plan view of the one-way clutch in the 1 to describe the operation of the cage ring of the one-way clutch in the 1 a, b ;
• 3 a schematic three-dimensional representation of a section of the one-way clutch of the preceding figures;
• 4 a further schematic, three-dimensional representation of another section of the one-way clutch of the preceding figures.

The 1a, b show in a schematic, lateral plan view of a section of a one-way clutch 1 how this can be used, for example, in vehicle transmissions for the selective coupling and decoupling of two coupling partners. The one-way clutch 1 has a first ring 2 which acts as an outer ring 3 is formed, and a second ring 4 on, with the second ring as an inner ring 5 is trained. The first and / or the second ring 2 . 3 can - as in the 1a, b shown - be formed in one or more parts. Between the first ring 2 and the second ring 3 is an annular gap 6 present, in which a plurality of clamping bodies 7 , which are designed as pinch rollers, are arranged. The roller axes of the clamp body 7 are parallel to a main axis of the one-way clutch 1 aligned.

The inner ring 5 has a career 8th for unrolling the clamping body 7 on. The career 8th is formed by a straight cylindrical surface. Of the outer ring 3 is as a ramp ring 9 formed, which in the direction of rotation about the main axis of the one-way clutch 1 a plurality of ramp areas 10 having. In each of the ramp areas 10 is one of the clamp body 7 arranged. The ramp areas 10 each have a free section 11 and a subsequent thereto in the circumferential direction clamping portion 12 on. The free width of the annular gap 6 in the radial direction is in the free section 11 greater than or equal to the outer diameter of the clamp body 7 sized. In the clamping section 12 the annular gap narrows 6 , so that the free diameter of the annular gap 6 in the clamping section 12 smaller than the outer diameter of the clamp body 7 is trained or in progress. The clamp body 7 are each by a spring 13 in the direction of the clamping sections 12 looking forward. The feathers 13 are supported as compression springs opposite the ramp ring 9 from. On the opposite side of the clamp body 7 in the direction of rotation are webs 14 arranged, which, however, in the 1a, b are graphically suppressed.

In the 1a is the one-way clutch 1 shown in a freewheeling state, wherein the inner ring 5 in a direction of rotation U rotates. The outer ring 3 and / or the ramp ring 9 is stationary. Alternatively, could also be the outer ring 3 and / or ramp ring 9 rotate in a counter-rotating direction to the one-way clutch 1 to keep in the freewheeling state. As a result, in a relative rotation between the inner ring 5 and the outer ring 3 a rotation of the inner ring 5 in the direction of rotation U opposite the outer ring 3 present to the one-way clutch 1 to keep in the freewheeling state. In the freewheeling state, the clamp body rotates 7 and rolls in the free section 11 on the track 8th of the inner ring 5 and in the free section 11 from. To limit the free section 11 can be an end section 15 be provided with a very large clamping angle to clamp the clamp body 7 to prevent.

In the 1b is the one-way clutch 1 shown in the clamping state. The clamping state is taken when the inner ring 5 is rotated in the counter-rotating direction. In the clamping state, the clamping body runs 7 in the clamping section 12 and clamped inner ring 5 with the outer ring 3 and / or the ramp ring 9 , Also for the clamping state is a relative rotation relative to the outer ring 3 or to the ramp ring 9 sufficient. By a further rotation of the inner ring 5 in the counter-rotation direction, the clamping force is amplified, so that a torque from the inner ring 5 on the outer ring 3 can be transferred. In the event that the torque to be transmitted is too high, however, the ramp ring 9 or the inner ring 5 to be damaged. To avoid such damage, the one-way clutch 1 the footbridges 14 on whose functioning in connection with the 2a, b is explained.

As especially in connection with the 3 . 4 will be revealed are the bars 14 integral components of a cage cage 16 , The cage ring 16 has a side ring section 17 on which the webs 14 at the side ring portion 17 are formed.

The 2a, b show a schematic representation in a lateral plan view of the one-way clutch 1 with the cage ring 16 in a freewheeling position ( 2a ) and in a clamping position ( 2 B ). In the 2a is the footbridge 14 in a freewheeling position. In the freewheeling position is the bridge 14 with its contact surface 18 positioned so that the clamp body 7 not in the clamping section 12 can retract. The contact surface 18 forms a clamping angle of 90 ° relative to the clamping body 7 out, so that the clamping body 7 against the jetty 14 can run without jamming or the like. In this condition is the one-way clutch 1 switched in both directions of rotation freewheeling. A frictional coupling between the outer ring 3 and the inner ring 5 can not. In particular, the bridge is located 14 , in particular the contact surface 18 between the clamp body 7 and the clamping portion 12 ,

In the 2 B are the jetty 14 and thus the ramp ring 9 in a clamping position. In the clamping position, the clamping body 7 in the clamping section 12 retract and the outer ring 3 , especially the ramp ring 9 , with the inner ring 5 jam. In the event that the torque to be transmitted between the coupling partner is very large, the clamping body moves 7 continue in the clamping section 12 one. If the torque to be transmitted is too large, causing damage to the one-way clutch 1 is to be feared forms the footbridge 14 with the contact surface 18 a common contact contour as a common end stop for the clamp body 7 , In the in the 2 B shown overload situation contacts the clamp body 7 both the clamping section 12 as well as the contact surface 18 and / or the jetty 14 , This forms the bridge 14 and the clamping portion 12 the common contact contour for the clamping body 7 , which is the clamping body 7 achieved when the one-way clutch 1 in an overload situation.

After the run-up surface 18 assumes a large clamping angle, in particular a clamping angle of 90 °, the contact with the common contact contour leads to a sudden increase in the effective clamping angle, so that a part of the clamping force on the web 14 is derived. As a result, the proportion of the clamping force, which over the clamping portion 12 is derived, leaps and bounds decreases, allowing the clamping between the outer ring 3 , the clamp body 7 and the inner ring 5 is suddenly reduced and thus the inner ring 5 relative to the outer ring 3 slip through and turn it. This process, which is also called rolling over, leads to the fact that at a very high torque overload protection is realized, the one-way clutch 1 protects against mechanical damage.

By switching the cage ring 16 between the clamping position and the free-running position, it is possible to use the one-way clutch 1 to switch between the clamping function and the freewheeling function. Because of the bridge 14 , in particular the contact surface 18 of the footbridge 14 , between the clamp body 7 and the clamping portion 12 can be arranged is ensured in the freewheeling function that no accidental jamming can take place. Because of the bridge 14 , in particular the contact surface 18 of the footbridge 14 with the clamping section 12 a common investment contour for the clamp body 7 can form as an overload contour, overrunning in case of overload can be represented reliably.

In the 3 is a schematic three-dimensional representation of the one-way clutch 1 shown. It can be seen that the outer ring 3 as a ramp ring 9 is formed at least two parts, wherein an inner ramp ring section 19 the ramp areas 10 wears and an outer ramp ring section 20 having an external toothing. The inner ramp ring section 19 and the outer ramp ring section 20 are rotatably connected. At the inner ramp ring section 19 are sliding sections 21 Arranged on the track 8th of the inner ring 5 slide. At the inner ramp ring section 19 The springs are supported 13 and press against the clamp body 7 , The bridges 14 are over the side ring section 17 in one piece as the cage ring 16 educated. Between the inner ramp ring section 19 and / or the outer ring 3 and the cage ring 16 is a spring device 22 arranged, which the cage ring 16 presses in the clamping position.

In the 4 is a detail of the one-way clutch 1 wherein it can be seen that the cage ring 16 by a relative displacement to the ramp ring 9 and / or to the outer ring 3 is pivotable in the direction of rotation to reach the release position or the clamping position.

LIST OF REFERENCE NUMBERS

1

way clutch

2

first ring

3

outer ring

4

second ring

5

inner ring

6

annular gap

7

clamping bodies

8th

career

9

ramp ring

10

ramp area

11

free section

12

clamping section

13

feather

14

web

15

end

16

cage ring

17

Side ring section

18

approach surface

19

inner ramp ring section

20

outer ramp ring section

21

sliding portions

22

spring means

U

direction of rotation

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102008049799 A1 [0003]
• DE 102015209309 A1 [0005]

Claims (10)

One-way clutch (1) with a first ring (2) and with a second ring (4), with a plurality of clamping bodies (7), wherein the clamping body (7) in an annular gap (6) between the first and the second ring (2 , 4), wherein one of the rings (2) is formed as a ramp ring (9) and has a plurality of circumferentially extending ramp areas (10), wherein the clamping bodies (7) in the ramp areas (10) are arranged the ramp areas (10) have a free portion (11) and a clamping portion (12), wherein the one-way clutch (1) is in a freewheeling state when the clamping bodies (7) are arranged in the free portion (11) and wherein the one-way clutch (1) in a clamping state, when the clamping body (7) in the clamping portion (12) are arranged, with a plurality of webs (14), wherein the webs (14) can form a run-up for the clamping body (7), characterized in that the webs (14) relative to the ramp ring (9) Umla ufrichtung are rotatable, wherein in a freewheeling position, the webs (14) respectively between the clamping portion (12) and the clamping body (7) are arranged and in a clamping position, the webs (14) each release the clamping portion (12). One-way clutch (1) to Claim 1 , characterized in that in the clamping position of the web (14) and the clamping portion (12) each form a common contact contour for the clamping body. One-way clutch (1) to Claim 1 or 2 , characterized in that the webs (14) each have a contact surface (18), wherein the contact surface (18) is aligned in the radial direction. One-way clutch (1) to Claim 1 or 2 , characterized in that the webs (14) by a cage ring (16) are formed. One-way clutch (1) to Claim 4 characterized by spring means (22), wherein the spring means (22) acts between the ramp ring (9) and the cage ring (16) and moves the cage ring (16) to the clamping position. One-way clutch (1) according to one of the preceding Claims 4 or 5 characterized by an actuator for switching the cage ring (16) from the clamping position to the freewheeling position and / or from the freewheeling position to the clamping position. One-way clutch (1) according to one of the preceding claims, characterized in that the ramp ring (9) is designed as an outer ring (3). One-way clutch (1) according to one of the preceding claims, characterized in that the clamping bodies (7) are designed as pinch rollers. One-way clutch (1) according to one of the preceding claims, characterized in that the ramp areas (10) each have an end portion (15) as a discharge section. Vehicle transmission for a vehicle, characterized by a one-way clutch (1) according to one of the preceding claims.

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