DE112008002026B4 - Coupling device with improved flow equalization - Google Patents

Abstract

Coupling device (2) with a compressible disk pack (16), a disk carrier (10) assigned to the disk pack (16) and an axially displaceable actuating piston (32) for compressing the disk pack (16), with the actuating piston (32) on one side A first pressure chamber (36) is provided, which can be pressurized in such a way that the actuating piston (32) can be displaced in the axial direction against the restoring force of a spring element (46), and on the other side of the actuating piston (32) a first compensation chamber (50 ) is provided, which is delimited by the actuating piston (32) and the disk carrier (10), whereby an axial force acting on the actuating piston (32) by rotating the clutch device (2) in the first pressure chamber (36) by a radially running first centrifugal oil column (72) and in the first compensation chamber (50) through a radially extending second centrifugal oil column on the actuating piston (32 ) acting opposite axial force (74) can be generated and an overflow channel (62) for partially discharging the oil from the first compensation chamber (50) opens into the first compensation chamber (50) such that the length (c) of the second column of centrifugal oil in the radial direction It is shortened that the opposing axial forces (72, 74) acting on the actuating piston (32) equalize, characterized in that a sealing element (56) is provided between the actuating piston (32) and the disk carrier (10), which is applied in this way the actuating piston (32) is arranged such that the overflow channel (62) is formed between the actuating piston (32) and the sealing element (56).

Description

The present invention relates to a clutch device with a compressible disk pack, a disk carrier assigned to the disk pack and an axially displaceable actuating piston for compressing the disk pack, rotation of the clutch device exerting a radial first centrifugal oil column and a radially extending second centrifugal oil column on the actuating piston.

From the EP 1 612 444 A1 a clutch device is known which has a compressible disk pack, a disk carrier assigned to the disk pack and an axially displaceable actuating piston for compressing the disk pack. A first pressure chamber is provided on one side of the actuating piston and 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 space is provided, which is delimited by the actuating piston and the disk carrier. By rotating the coupling device, an axial force acting on the actuating piston is generated in the first pressure chamber by a radially extending first centrifugal oil column and an opposite axial force acting on the actuating piston in the first compensation chamber by a radially extending second centrifugal oil column. In order to keep the axial length of the clutch device as short as possible, the actuating piston and the disk carrier are pushed into one another in the axial direction or nested in the radial direction such that the first column of centrifugal oil in the first pressure chamber and the second column of centrifugal oil in the first compensation chamber have different lengths. When the known coupling device rotates, this 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 pushed 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 initial position.

The DE 203 20 467 U1 proposes to arrange a baffle plate in the compensation space so that an overflow channel is arranged between the baffle plate and the plate carrier. This overflow channel opens into the compensation space in such a way that the column of centrifugal oil in the compensation space is shortened. The oil discharged via the overflow channel flows through openings in the plate carrier to the plate pack. A similar coupling device is also from the EP 1 382 875 A1 known.

The known coupling devices have proven themselves with regard to flow equalization, but are relatively complex to construct and manufacture.

On the basis of the known prior art, it is an object of the present invention to provide a coupling device of the generic type which, on the one hand, has a small axial length and in which an almost complete fluid level compensation takes place and, on the other hand, its manufacture is simplified.

This object is achieved by the features specified in claim 1. Advantageous embodiments of the invention are the subject of the dependent claims.

The clutch device according to the invention, which is preferably a double clutch, has a compressible disk set. A compressible plate pack can be understood to mean, for example, a plate pack made up of outer plates on the input or output side and inner plates on the output or drive side. The clutch device further comprises a disk carrier assigned to the disk pack, which can be, for example, an outer or inner disk carrier. Furthermore, the coupling device has an axially displaceable actuating piston for compressing the disk pack. A first pressure chamber is provided on one side of the actuating piston and can be pressurized in such a way that the actuating piston can be displaced in the axial direction against the restoring force of a spring element. On the other side of the actuating piston, a first compensation space 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, whereby by rotating the coupling device in the first pressure chamber by means of a radially running first centrifugal oil column, an axial force acting on the actuating piston and in the first compensating chamber by means of a radially extending second centrifugal oil column acting on the actuating piston opposite axial force can be generated. An overflow channel for partially discharging the oil from the first compensation chamber opens into the first compensation chamber in such a way that the length of the second column of centrifugal oil is shortened in the radial direction in such a way that the opposing axial forces acting on the actuating piston compensate. On the one hand, complete flow equalization can be achieved, and on the other hand, the axial length of the coupling device can be small. The latter is due to the fact that the first pressure chamber and the first compensation chamber have different lengths in the radial direction can be designed to achieve an optimized nesting of the actuating piston and lamella carrier, especially since the flow level compensation is achieved by a simple, appropriately positioned overflow channel or an overflow opening. Since the axial forces acting counter to the actuating piston compensate or cancel each other, only a spring element with a low restoring force is required to hold the actuating piston in its starting position. In order to enable simple manufacture of such a coupling device, a sealing element is provided between the actuating piston and the disk carrier, which is arranged on the actuating piston in such a way that the overflow channel is formed between the actuating piston and the sealing element. First of all, the coupling device with the first pressure chamber and the first compensation chamber can be completely designed and built, in order to then attach a correspondingly modified sealing element for the flow equalization.

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

In order to further simplify the manufacture of the coupling device, the sealing element is placed on the actuating piston in a further preferred embodiment of the coupling device according to the invention. For example, the sealing element can be attached to a protruding bulge of the actuating piston.

In a further preferred embodiment of the coupling device according to the invention, the sealing element is supported in the axial direction on the side of the actuating piston facing the disk carrier so that the axial forces which arise in the first compensation chamber from the second centrifugal oil column in the first compensation chamber can be transmitted safely.

According to a further preferred embodiment of the coupling device according to the invention, the sealing element is annular. In this way, the sealing element can completely enclose the hub of the clutch device and also ensure a circumferential seal between the actuating piston on the one hand and the disk carrier on the other hand, so that the first compensation space 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. 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 supported on a surface pointing in the axial direction and the other leg of the L-shaped cross section is supported on a surface of the actuating piston pointing in the radial direction. This also enables the sealing element to 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 has, on its side facing the actuating piston, protruding support sections for support on the actuating piston. In this way, the overflow channel can be formed in a particularly simple manner between the protruding support sections, the sealing element and the surface of the actuating piston, without complex machining of the actuating piston itself being necessary.

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 space other than the first pressure space. This prevents the pressure or oil pressure within the first pressure chamber from being reduced or increased, which simplifies the control of the actuating piston.

In a particularly advantageous embodiment of the coupling device according to the invention, the outlet opening opens into a further space which is delimited by the actuating piston and the disk carrier and is arranged radially further outside than the compensation space. In this way it is ensured that the centrifugal oil emerging from the first compensation chamber via the overflow channel is reliably discharged and the first pressure chamber is not influenced thereby.

In a further particularly preferred embodiment of the clutch device according to the invention, the disk carrier is an outer disk carrier. With a first compensation room Between the actuating piston and the outer disk carrier, the flow level compensation is particularly difficult, but the construction of the coupling device according to the invention also enables a short axial length of the same in this embodiment.

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

In order to largely maintain the pressure within the second pressure chamber even in the case of a coupling device which is designed as a double clutch, the overflow channel has an outlet opening which opens into a space other than the second pressure chamber. For example, the outlet opening can open into the aforementioned further space, which is delimited by the actuating piston and the disk carrier.

In a further preferred embodiment of the clutch device according to the invention, the first disk pack is a disk pack that is outer in the radial direction and the second disk pack is a disk pack that is inner in the radial direction. The invention thus offers a particularly simple solution for the flow equalization of the outer clutch of a double clutch.

In a further particularly advantageous embodiment of the coupling device according to the invention, the second pressure chamber can also be pressurized in such a way that the second actuating piston can be displaced in the axial direction against the restoring force of a spring element. As already explained above, the spring element only has to exert a slight restoring force due to the fluid level 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 thereof. Furthermore, the controllability or sensitivity of the coupling device is improved.

• 1 eine Seitenansicht einer Ausführungsform der erfindungsgemäßen Kupplungseinrichtung in geschnittener Darstellung und
• 2 eine vergrößerte Darstellung des Ausschnitts A von 1.

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

• 1 a side view of an embodiment of the coupling device according to the invention in a sectional view and
• 2 an enlarged view of section A of 1 ,

1 shows an embodiment of the coupling device according to the invention 2 in cross-section, with reference to the longitudinal or rotational axis 4 around which the rotatable parts of the coupling device 2 turn, 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 an input hub on the motor side 6 on. The input hub 6 is non-rotatable with a drive plate 8th connected. The drive plate 8th is non-rotatable with an outer disk carrier 10 connected. The outer disk carrier 10 has an outer support section 12 and an inner support section 14 on. During the outer support section 12 non-rotatable with the outer slats of an outer, compressible first slat package 16 is connected is the inner support section 14 non-rotatable with the outer slats of an inner, compressible second plate pack 18 connected.

The coupling device 2 also has an outer inner disk carrier 20 and an inner inner disk carrier 22 on. Both inner disk carriers 20 . 22 each have a support section at their radially outward-facing end 24 . 26 on, the non-rotatable with the inner plates of the first plate pack 16 or with the inner plates of the second plate pack 18 connected is. The outer inner disk carrier 20 is rotationally fixed at its radially inward end with a first output hub 28 connected while the inner inner disk carrier 22 at its radially inward end rotatably with a second output hub 30 connected is.

The coupling device 2 also has an axially displaceable first actuating piston 32 for compressing the first plate pack 16 and an axially displaceable second actuating piston 34 to compress the second plate pack 18 on. On each side of the first or second actuating piston 32 . 34 is a first pressure room 36 or a second pressure room 38 educated. The pressure rooms 36 respectively. 38 can each have a hole 40 respectively. 42 in the clutch hub 44 filled with oil and thus pressurized in such a way that the first or second actuating piston 32 . 34 against the restoring force of a spring element 46 respectively. 48 is moved in the axial direction.

Further features of the coupling device according to the invention 2 are described below with reference to 2 explains the section A of 1 represents enlarged. On the other side of the first actuating piston 32 is a first compensation room 50 intended. The second actuating piston also has a similar manner 34 a second compensation room 52 on ( 1 ). The first compensation room 50 is from the first actuating piston 32 , the outer disk carrier 10 and the clutch hub 44 limited, with a sealing element explained later in detail a gap between the actuating piston 32 and the outer disk carrier 10 seals. To the first compensation room 50 To be able to fill with oil is in the coupling hub 44 also another hole 54 provided that in the first compensation room 50 empties. The first actuating piston 32 and the outer disk carrier 10 are in the area of the first pressure chamber 36 and the first compensation room 50 bulged in an axial direction such that they can be pushed one into the other in the axial direction or are nested in the radial direction.

Between the first actuating piston 32 and the outer disk carrier 10 is a sealing element 56 intended. The sealing element 56 is ring-shaped and on the actuating piston 32 attached. The sealing element 56 has an L-shaped cross section and is in the region of the bulge on the first actuating piston 32 attached. Here is the sealing element 56 in the axial direction on the outer disk carrier 10 facing side of the first actuating piston 32 supported.

On the first actuating piston 32 facing side of the radially extending leg 58 of the L-shaped cross section of the sealing element 56 are protruding support sections 60 to support the sealing element 56 on the first actuating piston 32 intended. This creates between the protruding support sections 60 an overflow channel 62 which is in the axial direction of 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 is limited.

The overflow channel 62 ends with an entry opening 64 that on the inner diameter of the sealing element 56 is arranged in the first compensation room 50 , The overflow channel 62 also points to the outer diameter of the sealing element 56 and thus in the area of the axially extending leg 66 of the L-shaped cross section of the sealing element 56 an exit opening 68 on. The exit opening 68 of the overflow channel 62 flows into another room 70 from the first actuating piston 32 and the outer disk carrier 10 limited and radially further outside than the first compensation space 50 is arranged, the further room 70 with the help of the sealing lip (no reference number) of the sealing element 56 at least partially compared to the first compensation room 50 is sealed. The exit opening 68 of the overflow channel 62 neither opens into the first pressure chamber 36 still in the second pressure room 38 ,

Below are further features of the invention and how it works with reference to FIG 2 explained. By rotating the coupling device 2 around the axis of rotation 4 a radially running, fixed first column of centrifugal oil is created in the first pressure chamber 36 with a length a in the radial direction. This first column of centrifugal oil extends from the inlet of the bore 40 up to the radially outermost edge of the first pressure chamber 36 , This first column of centrifugal oil acts due to the rotation of the coupling device 2 a pressure increase in the first pressure chamber 36 , from which one on the first actuating piston 32 acting axial force results in 2 from the arrow 72 is indicated.

At the same time, the rotation of the coupling device creates 2 on the other side of the first actuating piston 32 a radially extending, fixed second column of centrifugal oil in the first compensation chamber 50 , However, this second column of centrifugal oil does not extend over a length b from the inlet opening of the bore 54 to the outermost radial edge of the first compensation space 50 , Rather, the overflow channel 62 that part of the oil within the first compensation space 50 through the entrance opening 64 , the overflow channel 62 and the exit opening 68 in the further room 70 is dissipated. Due to the arrangement of the entry opening 64 within the first compensation room 50 part of the oil therefore flows out of the first compensation chamber 50 so that the fixed, second column of centrifugal oil only extends from the inlet opening 64 in the radial direction up to the radially outermost boundary of the first compensation space 50 over a length c extends in the radial direction, which is smaller than the aforementioned length b is.

The fixed second column of centrifugal oil with the shortened length c in the radial direction thus generates a fluid pressure within the first compensation space 50 that over the radial leg 58 of the L-shaped cross section of the sealing element 56 an axial force on the first actuating piston 32 exercises that in 2 from the arrow 74 indicated and the axial force 72 is opposite. The length of the second column of centrifugal oil is here by appropriate arrangement of the inlet opening 64 of the overflow channel 62 within the first compensation room 50 shortened so that the opposite axial forces 72 . 74 balance or cancel. Among other things, this has the advantage that the spring element 46 to reset the first actuating piston 32 in its starting position only has to exert a small restoring force.

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

LIST OF REFERENCE NUMBERS

2

coupling device

4

axis of rotation

6

input hub

8th

driver disc

10

External disk carrier

12

outer support section

14

inner support section

16

first plate pack

18

second plate pack

20

outer inner disk carrier

22

inner inner disk carrier

24

supporting section

26

supporting section

28

first output hub

30

second output hub

32

first actuating piston

34

second actuating piston

36

first pressure room

38

second pressure room

40

drilling

42

drilling

44

clutch

46

spring element

48

spring element

50

first compensation room

52

second compensation room

54

drilling

56

sealing element

58

radially extending leg

60

supporting sections

62

Overflow channel

64

inlet opening

66

axially extending leg

68

outlet opening

70

further room

72

axial force

74

opposite axial force

a

Length of the first column of centrifugal oil

b

length

c

Length of the second column of centrifugal oil

Claims (10)

Coupling device (2) with a compressible disk pack (16), a disk carrier (10) assigned to the disk pack (16) and an axially displaceable actuating piston (32) for compressing the disk pack (16), with the actuating piston (32) on one side A first pressure chamber (36) is provided, which can be pressurized in such a way that the actuating piston (32) can be displaced in the axial direction against the restoring force of a spring element (46), and on the other side of the actuating piston (32) a first compensation chamber (50 ) is provided, which is delimited by the actuating piston (32) and the disk carrier (10), an axial force acting on the actuating piston (32) by rotating the clutch device (2) in the first pressure chamber (36) by a radially running first column of centrifugal oil (72) and in the first compensation chamber (50) by means of a radially running second column of centrifugal oil on the actuating piston (32 ) acting opposite axial force (74) can be generated and an overflow channel (62) for partially discharging the oil from the first compensation chamber (50) opens into the first compensation chamber (50) in such a way that the length (c) of the second column of centrifugal oil in the radial direction It is shortened that the opposing axial forces (72, 74) acting on the actuating piston (32) equalize, characterized in that a sealing element (56) is provided between the actuating piston (32) and the disk carrier (10), which is applied in this way the actuating piston (32) is arranged such that the overflow channel (62) is formed between the actuating piston (32) and the sealing element (56). Coupling device after Claim 1 , characterized in that the sealing element (56) is attached to the actuating piston (32), preferably attached to the actuating piston (32). Coupling device after Claim 2 , characterized in that the sealing element (56) in the axial direction on the plate carrier (10) facing side of the actuating piston (32) is supported. Coupling device according to one of the Claims 2 or 3 , characterized in that the sealing element (56) is ring-shaped, the inlet opening (64) of the overflow channel (62), which is preferably provided on the inside diameter of the sealing element (56), being more preferably radially inward 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). Coupling device after Claim 4 , characterized in that the sealing element (56) has an L-shaped cross section. Coupling device according to one of the Claims 2 to 5 , characterized in that the sealing element (56) has on its side facing the actuating piston (32) protruding support sections (60) for support on the actuating piston (32). 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 space other than the first pressure chamber (36), the outlet opening (68) preferably into a further space (70 ) opens out, which is delimited by the actuating piston (32) and the disk carrier (10) and is arranged radially further outward than the compensation chamber (50). Coupling device according to one of the preceding claims, characterized in that the plate carrier (10) is an outer plate carrier. Coupling device according to one of the preceding claims, characterized in that a second actuating piston (34) is provided for compressing a compressible second plate pack (18), to which a second pressure chamber (38) is assigned, which can be pressurized in such a way that the second actuating piston (34) is displaceable in the axial direction, the overflow channel (62) preferably having an outlet opening (68) which opens into a space other than the second pressure space (38), the first plate pack (16) particularly preferably opening in the radial direction outer disk pack and the second disk pack (18) is an inner disk pack in the radial direction. Coupling device after Claim 9 , characterized in that the second pressure chamber (38) can be pressurized in such a way that the second actuating piston (34) can be displaced in the axial direction against the restoring force of a spring element (48).

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