WO2009021582A1 - Coupling device with improved hydraulic oil compensation - Google Patents

Abstract

The invention relates to a coupling device (2) having a compressible disc assembly (16), a disc carrier (10) associated with the disc assembly (16), and an axially displaceable actuating piston (32) for compressing the disc assembly (16), a first pressure chamber (36) being provided that may be placed under pressure such that the actuating piston (32) may be displaced in the axial direction and a first compensation chamber (50) being provided on the other side of the actuating piston (32) that is limited by the actuating piston (32) and the disc carrier (10). Due to rotation, the pressure is increased in the first pressure chamber (36) by a first radial hydraulic oil column such that an axial force (72) acting on the actuating piston (32) results. At the same time, upon rotation, the pressure in the first compensation chamber (50) is increased due to a second radial hydraulic oil column such that an additional axial force (74) counter to the axial force (72) is generated on the actuating piston (32). According to the invention, an overflow channel (62) for partially removing the oil from the first compensation chamber (50) opens into the first compensation chamber (50) such that the length (c) of the second hydraulic oil column is truncated in the radial direction such that the opposing axial forces (72, 74) acting on the actuation piston (32) equalize.

Description

 Coupling device with improved centrifugal oil compensation

description

The present invention relates to a coupling device with a compressible disk set, a disk carrier associated with the disk carrier and an axially displaceable actuating piston for compressing the disk set, wherein by rotation of the coupling means a radially extending first

Fliehölsäule and a radially extending second Fliehöl- column exert opposite axial forces on the actuating piston.

Coupling devices, in particular multi-disc clutches, are known from the prior art, which have a compressible disk set, a disk carrier associated with the disk set and an axially displaceable actuating piston for compressing the disk pack. On the one side of the actuating piston, a first pressure chamber is provided, which can be pressurized in such a way that the actuating piston can be displaced in the axial direction. On the other side of the actuating piston, a first compensation chamber is provided which is delimited by the actuating piston and the disk carrier. By rotation of the coupling device is in the first pressure chamber by a radially extending first centrifugal oil column acting on the actuating piston axial force and in the first compensation space by a radially extending second

Centrifugal oil column acting on the actuating piston generated opposite axial force. In order to keep the axial length of the coupling device as small as possible, the actuating piston and the plate carrier are pushed into each other in the axial direction or nested in the radial direction such that the first Fliehölsäule in the first pressure chamber and the second Fliehölsäule in the first expansion chamber have different lengths. This results in rotation of the known coupling means that either the axial force in one direction or the axial force in the other direction is greater, so that the actuating piston is always urged in one of the two axial directions during operation of the known coupling devices. To compensate for this, for example, a stronger spring element must be provided for returning the piston to its starting position.

Starting from the known prior art, it is an object of the present invention to provide a coupling device of the generic type, on the one hand has a small axial length and on the other hand, a nearly complete Fliehölaus- equal.

This object is achieved by the in the claim

1 specified characteristics solved. Advantageous embodiments of the invention are the subject of the dependent claims.

The coupling device according to the invention, which is preferably a double clutch, has a compressible disk set. A compressible disk set may, for example, be understood to mean a disk set consisting of outer disk or driven-side outer disk and inner disk or drive-side disk. The coupling device further comprises a plate carrier associated with the plate carrier, at which may be, for example, an outer or inner plate carrier. Furthermore, the coupling device has an axially displaceable actuating piston for compressing the disk pack. On the one side of the actuating piston, a first pressure chamber is provided, which can be pressurized in such a way that the actuating piston can be displaced in the axial direction. On the other side of the actuating piston, a first compensation chamber is provided which is delimited by the actuating piston and the disk carrier. The first pressure chamber and the first compensation chamber can be filled with oil, wherein by rotation of the coupling device in the first pressure chamber by a radially extending first Fliehölsäule acting on the actuating piston axial force and in the first compensation chamber by a radially extending second Fliehölsäule acting on the actuating piston opposite axial force can be generated. According to the invention, an overflow channel or an overflow opening for partial removal of the oil from the first compensation chamber opens into the first compensation chamber such that the length of the second centrifugal oil column is shortened in the radial direction such that the opposing axial forces acting on the actuating piston equalize.

The invention has the advantage that on the one hand a complete centrifugal oil balance is achieved and on the other hand, the axial length of the coupling device can be low. The latter can be attributed to the fact that the first pressure chamber and the first compensation chamber can be of different lengths in the radial direction in order to achieve optimized nesting of actuating piston and plate carrier, especially since centrifugal oil compensation is achieved by a simple, appropriately positioned overflow channel or an overflow opening. is enough. Further, by equalizing or canceling the axial forces opposing the actuating piston, only a low restoring force spring element is required to hold the actuating piston in its initial position.

In order to enable a simple production of such a coupling device, in a preferred embodiment of the coupling device according to the invention, a sealing element is provided between the actuating piston and the plate carrier, which is arranged on the actuating piston such that the overflow channel is formed between the actuating piston and the sealing element. Alternatively, the overflow opening can be provided in the sealing element, wherein said overflow channel is preferred. In both cases, first of all, the coupling device with the first pressure chamber and the first compensation chamber can be completely constructed and constructed, in order subsequently to attach a correspondingly modified sealing element for the centrifugal oil compensation.

In order to ensure a secure hold of the sealing element on the actuating piston, the sealing element is fastened to the actuating piston in a further preferred embodiment. For example, the sealing element can be displaced in the axial direction together with the actuating piston.

In order to further simplify the production of the coupling device, the sealing element is plugged in a further preferred embodiment of the coupling device according to the invention on the actuating piston. For example, the sealing element can be attached to a protruding bulge of the actuating piston. So that the axial forces, which arise through the second flow column in the first compensation chamber, can be transferred securely to the actuating piston via the sealing element, the sealing element in a further preferred embodiment of the inventive coupling device is in the axial direction on the side of the actuating column facing the plate carrier - Bens truncated.

According to a further preferred embodiment of the inventive coupling device, the sealing element is annular. In this way, the sealing element can completely surround the hub of the coupling device and furthermore ensure a peripheral seal between the actuating piston, on the one hand, and the disk carrier, so that the first compensating chamber is completely sealed, at least in this area.

In an advantageous embodiment of the coupling device according to the invention, the inlet opening of the overflow channel is arranged radially further inwards than the outlet opening of the overflow channel. In this case, the inlet opening of the overflow channel is preferably provided on the inner diameter of the sealing element, while the outlet opening of the overflow channel is preferably provided on the outer diameter of the sealing element.

According to a further advantageous embodiment of the coupling device according to the invention, the annular sealing element has an L-shaped cross-section. Preferably, one leg of the L-shaped cross-section is at a surface facing in the axial direction and the other leg of the L-shaped cross section is at a radially pointing upper surface. supported surface of the actuating piston. This also makes it possible that the sealing element can be supported and attached in a simple manner to a protruding bulge of the actuating piston.

In a particularly preferred embodiment of the coupling device according to the invention, the sealing element on its side facing the actuating piston side protruding support portions for support zen on the actuating piston. In this way, the overflow channel can be particularly easily formed between the protruding support portions, the sealing member and the surface of the actuating piston, without a complex processing of the actuating piston itself would be required.

In a further particularly preferred embodiment of the coupling device according to the invention, the overflow channel has an outlet opening, which opens into a different space than the first pressure chamber. Alternatively, the overflow opening opens into a different space than the first pressure chamber, but here too, the aforementioned overflow channel is preferred. In both cases it is prevented that the pressure or oil pressure within the first pressure chamber is reduced or increased, whereby the control of the actuating piston is simplified.

In a particularly advantageous embodiment of the coupling device according to the invention, the outlet opening or the overflow opening opens into a further space, which is delimited by the actuating piston and the plate carrier and arranged radially further outward than the compensating space. In this way it is ensured that the centrifugal oil exiting via the overflow channel from the first expansion chamber is safely removed is and the first pressure chamber is not affected by this.

In a further particularly preferred embodiment of the coupling device according to the invention, the plate carrier is an outer plate carrier. In a first compensation space between the actuating piston and the outer disk carrier of Fliehölausgleich is particularly difficult, however, the structure of the coupling device according to the invention also allows a short axial length of the same in this embodiment.

In a further particularly advantageous embodiment of the coupling device according to the invention, the coupling device is designed at least as a double clutch, wherein a second actuating piston is provided for compressing a compressible second plate pack, which is associated with a second pressure chamber, which can be pressurized such that the second actuating piston in axial direction can be moved.

In order also in a coupling device, which is configured as a double clutch to maintain the pressure within the second pressure chamber substantially has the Ü berlaufkanal an outlet opening, which opens into a ^¬ of the space as the second pressure chamber. Alternatively, the overflow opening opens into a different space than the second pressure chamber. Thus, the outlet opening or the overflow opening, for example, open into the aforementioned further space, which is bounded by the actuating piston and the plate carrier.

In a further preferred embodiment of the coupling device according to the invention, the first disk pack is a radially outer disk. package and the second disk pack a radially inner disk set. The invention thus provides a particularly simple solution for the Fliehölausgleich the outer clutch of a dual clutch.

In a further particularly advantageous embodiment of the coupling device according to the invention, the first or second pressure chamber can be pressurized in such a way that the first or second actuating piston can be displaced in the axial direction counter to the restoring force of a spring element. As already explained above, the spring element only has to apply a small restoring force due to the centrifugal oil compensation according to the invention in order to push the first or second actuating piston back into its starting position. Such a spring element with a lower restoring force thus reduces the weight of the coupling device according to the invention and can also contribute to a shorter axial length of the same. Furthermore, the controllability or sensitivity of the coupling device is improved.

The invention will be explained in more detail below with reference to an exemplary embodiment with reference to the accompanying drawings. Show it:

1 is a side view of an embodiment of the coupling device according to the invention in a sectional representation and

2 is an enlarged view of the detail A of Fig. 1st

Fig. 1 shows an embodiment of the coupling device 2 according to the invention in cross section, wherein relative to the longitudinal or rotational axis 4, about which rotate the rotatable parts of the coupling device 2, only the upper part is shown. The coupling device 2 is designed as a multi-plate clutch in the form of a double clutch.

The coupling device 2 has a motor-side input hub 6. The input hub 6 is rotatably connected to a drive plate 8. The driver disk 8 is non-rotatably connected to an outer disk carrier 10. The outer disk carrier 10 has an outer support section 12 and an inner support section 14. While the outer support section 12 is connected in a rotationally fixed manner to the outer lamellae of an outer, compressible first lamella packet 16, the inner support section 14 is connected in a rotationally fixed manner to the outer lamellae of an inner, compressible second lamella packet 18.

The coupling device 2 also has an outer inner disk carrier 20 and an inner inner disk carrier 22. At their radially outward-pointing end, both inner disk carriers 20, 22 each have a carrying section 24, 26 which is connected in a rotationally fixed manner to the inner disks of the first disk set 16 or to the inner disks of the second disk pack 18. The outer inner disk carrier 20 is rotatably connected at its radially inwardly facing end to a first output hub 28, while the inner Innenlamellen- carrier 22 is rotatably connected at its radially inwardly facing end with a second output hub 30.

The coupling device 2 furthermore has an axially displaceable first actuating piston 32 for compressing the first disk set 16 together and an axially displaceable second actuating piston 34 for the purpose of compressing the first disk set 16. mendrucken the second plate pack 18. On each side of the first and second actuating piston 32, 34, a first pressure chamber 36 and a second pressure chamber 38 is formed. The pressure spaces 36 and 38 can be filled with oil in the clutch hub 44 via a respective bore 40 or 42 and thus be pressurized such that the first or second actuating piston 32, 34 counteracts the restoring force of a spring element 46 or 48 is moved in the axial direction.

Further features of the coupling device 2 according to the invention will be explained below with reference to FIG. 2, which shows the detail A of FIG. 1 enlarged. On the other side of the first actuating piston 32, a first compensation chamber 50 is provided. In a similar manner, the second actuating piston 34 also has a second compensation chamber 52 (FIG. 1). The first compensation chamber 50 is bounded by the first actuating piston 32, the outer disk carrier 10 and the clutch hub 44, wherein a later explained closer sealing element seals a gap between the Betati ^¬ tion piston 32 and the outer disk carrier 10. In order to fill the first compensation chamber 50 with oil, a further bore 54 is also provided in the clutch hub 44, which ports into the first compensation chamber 50. The first actuating piston 32 and the outer disk carrier 10 are bulged in an axial direction in the region of the first pressure chamber 36 and the first compensation chamber 50 in such a way that they can be pushed into one another in the axial direction or are arranged nested in the radial direction.

Between the first actuating piston 32 and the outer disk carrier 10, a sealing element 56 is provided. The sealing element 56 is annular. forms and attached to the actuating piston 32. The sealing element 56 has an L-shaped cross-section and is plugged onto the first actuating piston 32 in the region of the bulge. In this case, the sealing element 56 is supported in the axial direction on the side of the first actuating piston 32 facing the outer disk carrier 10.

On the side of the radially extending leg 58 of the L-shaped cross section of the sealing element 56 facing the first actuating piston 32, projecting support sections 60 for supporting the sealing element 56 on the first actuating piston 32 are provided. In this way, an overflow channel 62 is formed between the protruding support sections 60 and is delimited in the axial direction by the first actuating piston 32 on the one hand and the radially extending leg 58 of the L-shaped cross section of the sealing element 56 on the other hand.

The overflow channel 62 opens with an inlet opening 64 which is arranged on the inner diameter of the sealing element 56, in the first compensation chamber 50. The overflow channel 62 further points to the outer diameter of the sealing element 56 and thus in the region of the axially extending leg 66 of the L-shaped cross section of the sealing element 56 an outlet opening 68. The outlet opening 68 of the overflow channel 62 opens into a further space 70, which is bounded by the first actuating piston 32 and the outer disk carrier 10 and radially further outside than the first compensation chamber 50, wherein the further space 70 by means of the sealing lip (no reference numeral) of the Sealing element 56 is sealed at least partially against the first compensation chamber 50. The outlet opening 68 of the overflow channel 62 terminates neither in the first pressure chamber 36 nor in the second Pressure chamber 38.

Hereinafter, further features of the invention and their operation will be explained with reference to FIG. 2. By rotation of the coupling device 2 about the axis of rotation 4, initially a radially extending, stationary first centrifugal oil column is formed in the first pressure chamber 36 with a length a in the radial direction. This first Fliehölsäule extends from the inlet of the bore 40 to the radially outermost edge of the first pressure chamber 36. This first Fliehölsäule causes due to the rotation of the coupling device 2, a pressure increase in the first pressure chamber 36, resulting in an acting on the first actuating piston 32 axial force resulted, which is indicated in Fig. 2 by the arrow 72.

At the same time, due to the rotation of the coupling device 2 on the other side of the first actuating piston 32, a radially extending, stationary second centrifugal oil column is created in the first compensation chamber 50. However, this second centrifugal oil column does not extend over a length b from the inlet opening of the bore 54 Rather, the overflow channel 62 causes a portion of the oil within the first compensation chamber 50 to be discharged through the inlet opening 64, the overflow channel 62 and the outlet opening 68 into the further space 70. Due to the arrangement of the inlet opening 64 within the first compensation chamber 50 thus flows from a portion of the oil from the first compensation chamber 50, so that the fixed, second Fliehölsäule only from the inlet opening 64 in the radial direction to the radially outermost boundary of the first compensation chamber 50th extends over a length c in the radial direction, which is smaller than the aforementioned length b. The fixed second flow column with the shortened length c in the radial direction thus generates a fluid pressure within the first compensation chamber 50, which exerts an axial force on the first actuating piston 32 via the radially extending limb 58 of the L-shaped cross section of the sealing element 56, which in FIG. 2 indicated by the arrow 74 and the axial force 72 is opposite. The length of the second flow column is here shortened by appropriate arrangement of Eintπttsoffnung 64 of the overflow channel 62 within the first compensation chamber 50 such that the opposite axial forces 72, 74 compensate or cancel. This has the advantage, inter alia, that the spring element 46 only has to apply a small restoring force for returning the first actuating piston 32 to its initial position.

While only one overflow channel 62 has been described above, which is a preferred variant, the removal of the oil can also be effected via a simple overflow opening, which is preferably provided in the sealing element 56.

LIST OF REFERENCE NUMBERS

2 coupling device

4 rotation axis

6 input hub

8 driver disc

10 outer disk carrier

12 outer support section

14 inner support section

16 first disc pack

18 second disc pack

20 outer inner disk carrier

22 inner inner disk carrier

24 support section

26 supporting section

28 first output hub

30 second output hub

32 first actuating piston

34 second actuating piston

36 first pressure chamber

38 second pressure chamber

40 hole

42 bore

44 clutch hub

46 spring element

48 spring element

50 first equalization room

52 second equalization room

54 bore

56 sealing element

58 radially extending leg

60 support sections

62 overflow channel

64 entrance opening 66 axially extending leg

68 outlet opening

70 more room

72 Axial force 74 opposite axial force

a Length of the first centrifugal oil column b Length c Length of the second centrifugal oil column

Claims

claims 1. clutch device (2) with a compressible disk set (16), a the disk set (16) associated disk carrier (10) and an axially movable actuating piston (32) for Zusammendrucken the disk set (16), wherein on one side of the actuating piston (32 ) is provided, which can be acted upon by pressure in such a way that the actuating piston (32) is displaceable in the axial direction, and on the other side of the actuating piston (32), a first compensating space (50) is provided which the actuating piston (32) and the plate carrier (10) is limited, wherein by rotation of the coupling device (2) in the first pressure chamber (36) by a radially extending first flow column acting on the actuating piston (32) axial force (72) and in the first compensation chamber (50) by a radially extending second Flieholsaule on the actuating piston (32) acting opposite axial force (74) can be generated, dadur ch characterized in that an overflow channel (62) or an overflow opening for partial removal of the oil from the first compensation chamber (50) into the first compensation chamber (50) such that the length (c) of the second flow column is so shortened in the radial direction, in that the opposing axial forces (72, 74) acting on the actuating piston (32) cancel each other out. 2. Coupling device according to claim 1, characterized in that a sealing element (56) is provided between the actuating piston (32) and the disk carrier (10), the sealing element (56) being attached to the actuating piston (32) in such a way. is arranged, that the overflow channel (62) between the actuating piston (32) and the sealing element (56) is formed, or the overflow opening is provided in the sealing element. 3. Coupling device according to claim 2, characterized in that the sealing element (56) on the actuating piston (32) is attached. 4. Coupling device according to claim 3, characterized in that the sealing element (56) is attached to the actuating piston (32). 5. Coupling device according to one of claims 2 to 4, characterized in that the sealing element (56) is supported in the axial direction on the disk carrier (10) facing side of the actuating piston (32). 6. Coupling device according to one of claims 2 to 5, characterized in that the sealing element (56) is annular. 7. Coupling device according to claim 6, characterized in that the inlet opening (64) of the Ü overflow channel (62), which is preferably provided on the inner diameter of the sealing element (56), radially further inwardly than the outlet opening (68) of the overflow channel (62) is arranged, which is preferably provided on the outer diameter of the sealing element (56). 8. Coupling device according to one of claims 6 or 7, characterized in that the sealing element (56) has an L-shaped cross-section. 9. Coupling device according to one of claims 2 to 8, characterized in that the sealing element (56) on its the actuating piston (32) facing side projecting support portions (60) for supporting on the actuating piston (32). 10. Coupling device according to one of the preceding claims, characterized in that the overflow channel (62) has an outlet opening (68) which opens into a different space than the first pressure chamber (36), or that the overflow opening in a different space than the first Pressure chamber (36) opens. 11. Coupling device according to claim 10, character- ized in that the outlet opening (68) or the overflow opening, which opens into a further space (70) bounded by the actuating piston (32) and the plate carrier (10) and radially further outside is arranged as the compensation chamber (50). 12. Coupling device according to one of the preceding claims, characterized in that the disk carrier (10) is an outer disk carrier. 13. Coupling device according to one of the preceding Claims, characterized in that a second actuating piston (34) is provided for compressing a compressible second disc pack (18), which is associated with a second pressure chamber (38) which is pressurized in such a way that the second actuating piston (34) in axial Direction is displaceable. 14. A coupling device according to claim 13, character- ized in that the overflow channel (62) has an outlet opening (68) which in another Room as the second pressure chamber (38) opens, or that the overflow opening opens into a different space than the second pressure chamber (38). 15. Coupling device according to one of claims 13 or 14, characterized in that the first disk set (16) is a radially outer disk set and the second disk set (18) is an inner disk set in the radial direction. 16. Coupling device according to one of the preceding claims, characterized in that the first or second pressure chamber (36, 38) can be acted upon by pressure such that the first or second actuating piston (32, 34) counter to the restoring force of a spring element (46, 48) is displaceable in the axial direction.