WO2008049626A1

WO2008049626A1 - Clutch actuation apparatus for actuating a clutch

Info

Publication number: WO2008049626A1
Application number: PCT/EP2007/009302
Authority: WO
Inventors: Eduard Hilberer; Michael Herges
Original assignee: Knorr-Bremse Systeme für Nutzfahrzeuge GmbH
Priority date: 2006-10-27
Filing date: 2007-10-26
Publication date: 2008-05-02
Also published as: DE102006050802A1; DE102006050802B4

Abstract

The invention relates to a clutch actuation apparatus (10; 100; 200; 300; 400) for actuating a clutch (60), in particular the clutch of a motor vehicle, having a pressure chamber (14; 114; 214; 314; 414) with a variable volume, wherein a volumetric change of the pressure chamber (14; 114; 214; 314; 414) serves to actuate the clutch (60). There is provision according to the invention for the pressure chamber (14; 114; 214; 314; 414) to be delimited at least partially by a deformable, elastic element (20; 120; 220; 320; 420).

Description

Clutch actuating device for actuating a clutch

The invention relates to a Kupplungsbetätigungsvorrich- device for actuating a clutch, in particular that of a motor vehicle, having a pressure chamber whose volume is variable, wherein a volume change of the pressure chamber for actuating the clutch is used.

In motor vehicles, clutch actuation devices are usually used by means of which clutches for interrupting and restoring a force flow between an internal combustion engine and a motor vehicle transmission can be actuated. In addition to a purely mechanical control, such clutch actuating devices can also be controlled pneumatically, for example. In this case, they have a pressure chamber whose volume is variable. The variation of the volume or a change in volume of the pressure chamber takes place by means of a corresponding Druckauf- and pressure reduction in the pressure chamber. The change in volume of the pressure chamber ultimately causes the Actuation of the clutch and thus a decoupling or coupling of the internal combustion engine of or with the motor vehicle transmission. Usually, the pressure chamber is formed exclusively by rigid and inflexible or non-deformable components. At least one of these rigid components is movably mounted with respect to one or more other components via at least one first and second guide in order to vary the volume of the pressure chamber can. The first and second guides are each between the movable

Component and a stationary component, for example, realized by a sliding or in any other way. This requires a close adherence to tolerances of these rigid components, in particular between see each other coupled via a guide movable and immovable components to avoid leaks in the pressure chamber. As a result, the design and production-related expense for such clutch actuators is subject to strict design and manufacturing specifications. This has the consequence that their production is very costly.

The invention is therefore the object of developing the generic clutch actuation devices such that the design and manufacturing-related effort can be reduced.

This object is solved by the features of the independent claim. Advantageous embodiments and modifications of the invention will become apparent from the dependent claims.

The inventive clutch actuating device for actuating a clutch builds on the generic state of the art in that the pressure chamber is at least partially limited by a deformable and elastic element. The deformable or flexible and elastic element bounds at least a part of the pressure chamber. By contrast, for example, a movable and immovable rigid component limit the remaining part of the pressure chamber. In this case, the movable and immovable components may be coupled together via a first guide. Instead of a further coupling via a second guide between these components, the deformable, elastic element for limiting the pressure chamber is provided. This can, for example, be coated over the movable and immovable component or in each case attached to it. As a result, the construction and production-related effort is significantly reduced. Thus, compliance with strict tolerances due to the elastic and deformable element is not necessarily required.

The clutch actuating device according to the invention can be developed such that the pressure chamber is further limited by an actuating piston, which with the coupling is coupled. In this case, the actuating piston corresponds to a rigid and movable component for limiting the pressure chamber. The actuating piston as a movable rigid component is preferably designed as a hollow cylinder and serves to actuate the clutch. By moving the actuating piston, the volume of the pressure chamber is variable. Preferably, the elastic and deformable element is coupled to the movable actuating piston and the immovable rigid component for limiting the pressure chamber.

Moreover, the clutch actuating device according to the invention can be realized in such a way that the pressure chamber is further delimited by a housing component which movably guides the actuating piston. The housing component corresponds in this case, the immovable rigid component and may be partially designed as a hollow cylinder, which is flanged or disc-shaped at one end portion. In this context, the hollow cylindrical section of the housing component which guides the actuating piston movably serves to guide the actuating piston. The elastic and deformable element may, for example, be coated over an outer circumference of the hollow-cylindrical actuating piston and over the flange-shaped end section of the housing component. As a result, a further coupling via a second guide between a cylindrical outer jacket, which is provided in the direction of the actuating piston on the flange-shaped end section of the housing component, can be provided. hen, and the actuating piston can be omitted. In particular, further seals and scrapers required for the second guide can be replaced by the deformable and elastic element. This makes it possible, for example, to make the actuating piston smaller, in particular as a half-piston. In order to keep the friction between the actuating piston and the hollow cylindrical portion of the housing member low and to improve the leadership of the actuating piston, guide bushings, races or guide sleeves with or without wiper between them may be provided. Likewise, seals, such as rolling seals, may be arranged between them to ensure the tightness of the pressure chamber.

The clutch actuating device according to the invention can advantageously be further developed in such a way that the deformable, elastic element is a bellows spring, in particular a rolling bellows spring or a torus bellows spring. For example, the bellows spring may be a bellows spring commonly used in LkW air suspensions. Moreover, the bellows spring is capable of receiving a torque of a rolling bearing coupled to the actuating piston via the actuating piston. When using the Rollbalgfeder it can roll on appropriate movement of the actuating piston on the outer circumference of the actuating piston. In this context it can be provided that the clutch actuating device according to the invention is developed such that the Torusbalgfeder is associated with a predetermined spring hardness, with which the actuating piston is biased against the clutch. The

Spring hardness or spring constant can be achieved, for example, by attaching a helical spring around the outer circumference of, for example, the wave-shaped Torusbalgfeder. The term "wave-shaped" torus bellows spring in this context means a torus bellows spring whose shape corresponds to a hollow cylinder with corrugated lateral surfaces in the hollow cylinder longitudinal direction. Preferably, the coil spring extends in wave troughs or between wave crests of the wave-shaped Torusbalgfeder. Likewise, the spring but also in the

Torusbalgfeder be vulcanized. In this way, the spring, which is used superficially, for biasing the actuating piston against the coupling can be provided in a space-saving manner on the torus bellows spring.

In an alternative embodiment, the clutch actuating device according to the invention may be designed such that the deformable, elastic element is a membrane, in particular a rolling diaphragm or a pot membrane. For example, a pot diaphragm can be used, as it is commonly used in brake cylinders of motor vehicles. In particular, in this embodiment, it is preferable to further develop the clutch actuating device according to the invention in such a way that the diaphragm can be brought into abutment with a support wall. The support wall can be arranged in this case on a housing component, in particular on the flanschför- shaped end portion of the housing component. This can prevent damage to the membrane at too high pressure in the pressure chamber.

Likewise, the inventive Kupplungsbetätigungsvor- device can be realized so that the deformable elastic member is a pressure chamber forming to- rusförmiger hollow body with a ventilation dome. For example, the toroidal hollow body can be provided as a closed and toroidal rubber jacket such that it directly forms the pressure chamber, while the pressure chamber is limited indirectly or via the rubber jacket by the housing component, a support wall attached to the housing component and the actuating piston. The pressure in the pressure chamber can be increased and decreased via the ventilation dome. Preferably, the ventilation dome on a sealing bead.

In this connection, the clutch actuation device according to the invention can be carried out in such a way that a rubber spring, which preferably comprises a steel insert, is attached to the toroidal hollow body. As a result, the spring for biasing the Betätigungskol- Bens against the clutch is not necessarily necessary, but can still be optionally provided.

In particular, the clutch actuating device according to the invention can be developed in such a way that it is a central release device.

Although a variant with pneumatic control has been described above, it is clear to the person skilled in the art that the invention can also be implemented within the framework of a hydraulic system.

Preferred embodiments of the invention are explained below by way of example with reference to the figures.

Show it:

FIG. 1 shows a representation of the clutch actuation device according to the invention for actuating a clutch according to a first exemplary embodiment of the invention;

FIG. 2 shows an illustration of the clutch actuation device according to the invention for actuating a clutch according to a second exemplary embodiment of the invention;

FIG. 3 shows a representation of the clutch actuation device according to the invention for actuating a clutch actuation device Coupling according to a third embodiment of the invention;

FIG. 4 shows an illustration of the clutch actuation device according to the invention for actuating a clutch actuation device

Coupling according to a fourth embodiment of the invention;

FIG. 5 is an illustration of the clutch actuation device according to the invention for actuating a clutch actuation device

Coupling according to a fifth embodiment of the invention; and

Figure 6 shows a detail of a motor vehicle system in which the invention Kupplungsbetätigungs- devices of Figures 1 to 5 can be used.

Figure 1 shows an illustration of the clutch actuating device 10 according to the invention for actuating a

Clutch 60 of a motor vehicle according to a first embodiment of the invention. In the case shown, the clutch actuating device 10 is a Zentralausrücker. To illustrate the arrangement and functionality of the Kupplungsbetätig- device 10 according to the invention is first described in more detail Figure 6. FIG. 6 shows a section of a motor vehicle system. In this case, the automotive system includes an engine 70 and a motor vehicle transmission 80 coupled to the engine 70. To interrupt and reestablish power flow from the engine 70 to the motor vehicle transmission 80, the clutch 60 is provided therebetween. For this purpose, the clutch 60 is actuated by the clutch actuating device according to the invention. The illustration of FIG. 6 explicitly shows the inventive clutch actuating device 300 according to the fourth exemplary embodiment of the invention (FIG. 4). However, in the motor vehicle system of FIG. 6, the clutch actuation devices according to the invention according to the other embodiments may instead be provided as well.

Returning to FIG. 1, the clutch actuating device 10 according to the invention comprises a pressure chamber 14. The pressure chamber 14 is at least partially made of a flexible or deformable and elastic

Element 20 limited. The deformable elastic element 20 is a rolling bellows spring 16 in this exemplary embodiment. Furthermore, the pressure chamber 14 is delimited by a substantially hollow-cylindrical actuating piston 12, which is coupled to the coupling 60, and a housing component 18. The hollow cylindrical actuating piston 12 is guided on the inner periphery of the housing member 18 movable. The housing component 18 likewise has the shape of a hollow cylinder, which at its one end cut flange is formed. The rolling bellows spring 16 is mounted to limit the pressure chamber 14 to an outer periphery of the hollow cylindrical actuating piston 12 and the flange-shaped end portion of the housing member 18. Due to the movable guide of the actuating piston 12 and the flexibility of the Rollbalgfeder 16, the volume of the pressure chamber 14 is variable. At the flange-shaped end portion of the housing member 18 in Figure 1, a fastening thread 26 and a fixing 46 is provided. As a result, the clutch actuation device 10 according to the invention can be coupled by means of a screw connection, not shown, to a housing of the motor vehicle transmission 80 or a housing of the coupling 60, for example a clutch bell, and can be centered in particular via the fixation 46. In addition, a sensor receiver element 30 is fixed to the flange-shaped end section of the housing component 18, for example via a plug or another plug connection, which is connected to a sensor guide element 28 movable relative to the sensor receiving element 30. The sensor overflow element 28 is in turn coupled to the actuating piston 12, whereby a displacement detection of the actuating piston 12 is made possible. In this case, the sensor receiver element 30 and the sensor overflow element 28 are located in the pressure chamber 14. Furthermore, a spring 32 is provided between the actuating piston 12 and the flange-shaped end section of the housing component 18 in the pressure chamber 14, which biases the actuating piston 12 against the coupling 60 , Further, on the inner circumference of the actuating piston 12, two guide bushes 36, 40 and a seal 38 are respectively provided in grooves formed on the inner circumference, the guide bush 40 further comprising a scraper. In addition, a roller bearing 44 is attached to one of the coupling 60 side facing the actuating piston 12 to this, to minimize transmission of torque from the clutch 60 to the actuating piston 12. To limit a maximum disengaging movement of the actuating piston 12, a securing ring 42 is arranged on the hollow cylindrical section or hollow cylinder of the housing component 18. Thus, the actuating piston 12 between the locking ring 42 and the flange-shaped end portion of the housing member 18 is movably mounted. To vary the volume of the pressure chamber 14, a ventilation channel 34 is provided in the housing member 18, by means of which the pressure in the pressure chamber up and is degradable.

During operation of the clutch actuating device 10 according to the invention, a pressure in the pressure chamber 14 is increased or decreased via the ventilation channel 34. Accordingly, the actuating piston 12 moves in the event of pressure build-up in the direction of the clutch 60 or in the event of pressure reduction away from the latter against the bias of the spring 32. When pressure is reduced in the pressure chamber 14, the Rollbalgfeder 16 rolls at least in sections on the outer periphery of the actuating piston. Figure 2 shows an illustration of the clutch actuating device 100 according to the invention for actuating the clutch 60 according to a second embodiment of the invention. To avoid repetition, only the differences from the first exemplary embodiment will be explained in greater detail. Components of the clutch actuating device 100 of the second embodiment which are the same or similar to the first exemplary embodiment are designated by similar reference symbols or have been omitted. Instead of the rolling bellows spring 16 of the clutch actuating device 10 of the first exemplary embodiment, the clutch actuating device 100 of the second exemplary embodiment has a wave-shaped torus bellows spring 116. In addition, the Torusbalgfeder 116 is assigned a certain spring hardness. In this case, a spring 132 is provided on an outer peripheral surface of the Torusbalgfeder 116 to bias the actuating piston 112 against the clutch 60. Preferably, the spring 132 extends in troughs of the wave-shaped Torusbalgfeder 116. Furthermore, the Sensornehmerelement 130 and the Sensorgeberelement 128 are arranged outside of the pressure chamber 114.

The operation of the clutch operating device 100 of the second embodiment differs from that of the first embodiment in that the Torusbalgfeder 116 does not roll on depressurization in the pressure chamber 114 on the actuating piston 112, but by the wavy texture is compressed, similar to a fold-like bellows.

Figure 3 shows an illustration of the clutch actuating device 200 according to the invention according to a third embodiment of the invention. Again, only the differences from the first embodiment are explained in detail to avoid repetition. The same or similar components to the first embodiment of the clutch operating device 200 of the third embodiment of the invention will be denoted by like reference numerals or omitted. Instead of a bellows spring 16, 116 in the sense of the first and second exemplary embodiment, a rolling diaphragm 216 with a support wall 222 attached to the flange-shaped end section of the housing component 218 is provided in this exemplary embodiment. The support wall 222 extends in the direction of movement of the actuating piston 212 or parallel to the hollow cylindrical section of the housing component 218.

During operation, the rolling diaphragm 216 rolls in pressure chamber in the pressure chamber 214 similar to the rolling bellows spring 16 of the first embodiment of the actuating piston 212 from. However, in contrast to the first embodiment, the rolling diaphragm 216 is supported by the support wall 222 when pressure builds up in the pressure chamber 214. Figure 4 shows an illustration of the clutch actuating device 300 according to the invention for actuating the clutch 60 according to a fourth embodiment of the invention. In this case, only the differences from the third exemplary embodiment are explained in detail in order to avoid repetitions. The same or similar components of the first embodiment of the clutch operating device 300 of the fourth embodiment of the present invention will be denoted by like reference numerals or omitted. Instead of the rolling diaphragm 216 of the third embodiment, a pot diaphragm 316 having a support wall 322 attached to the flange-shaped end portion of the housing member 318 is provided in this embodiment.

Figure 5 shows an illustration of the clutch actuating device 400 according to the invention according to a fifth embodiment of the invention. To avoid repetition, only the differences from the first embodiment will be explained in more detail. The first

Embodiment identical or similar components of the clutch actuating device 400 according to the invention of the fifth embodiment are designated or omitted with similar reference numerals. In this exemplary embodiment, the pressure chamber 414 is formed exclusively by a toroidal hollow body 416. The toroidal hollow body 416 is designed, for example, as a closed rubber jacket. The toroidal hollow body 416 is in turn removed from the housing member 418, the actuating piston 412 and the support wall 422 limited, thus indirectly limit the pressure chamber 414. On the toroidal hollow body 416, a ventilation dome 434 is provided to allow Druckab- and pressure build-up of the pressure chamber 414. The ventilation dome 434 extends through the flange-shaped end portion of the housing component 418, for example through a bore. Preferably, an elastic rubber spring 424 is attached to the donut-shaped hollow body 416, which biases the actuating piston 412 in the direction of the coupling 60. Further, an optional spring 432 may be provided between the actuating piston 412 and the housing member 418, but this is not mandatory due to the attached rubber spring 424.

The features of the invention disclosed in the foregoing description, in the drawings and in the claims may be essential to the realization of the invention both individually and in any combination.

List of reference numbers:

10 clutch actuator 12 actuating piston

14 pressure chamber

16 rolling bellows spring

18 housing component

20 deformable, elastic element 26 fixing threads

28 Sensor support element 30 Sensor receiver element 32 Spring 34 Ventilation and ventilation duct

36 guide bush

38 seal

40 Guide bush with scraper 42 Circlip 44 Rolling bearing

46 fixation

60 clutch

70 internal combustion engine

80 Motor vehicle transmission 100 clutch actuating device

112 actuating piston

114 pressure chamber

116 Torusbalgfeder

118 Casing component 120 deformable, elastic element

126 fastening thread

128 sensor element

130 sensor pickup element

132 Spring 134 Ventilation and ventilation duct

136 guide bush

138 seal

140 Guide bush with scraper 142 Circlip 144 rolling bearings

200 clutch actuator

212 actuating piston

214 pressure chamber 216 rolling diaphragm

218 housing component

220 deformable, elastic element

222 retaining wall

228 Sensor element 230 Sensor element

232 spring

234 Ventilation duct 236 Guide bushing

238 Seal 240 Guide bush with scraper

242 circlip

244 rolling bearings

300 clutch actuator 312 actuating piston 314 pressure chamber

316 pot membrane

318 housing component

320 deformable, elastic element 322 support wall 328 Sensorkberelement

330 Sensor receiver element 332 spring

334 Ventilation and ventilation duct

336 guide bush 338 seal

340 Guide bush with scraper

342 Circlip

344 Rolling Bearings 400 Clutch Actuator

412 actuating piston

414 pressure chamber

416 toroidal hollow body

418 housing component 420 deformable, elastic element

422 support wall

424 rubber spring

428 sensor element

430 Sensor receiver element 432 optional spring

434 Ventilation dome

436 guide bushing

440 Guide bush with scraper 442 Circlip 444 Rolling bearing

Claims

claims

A clutch actuating device (10; 100; 200; 300; 400) for actuating a clutch (60), in particular a motor vehicle, having a pressure chamber (14; 114; 214; 314; 414) whose volume is variable, wherein a volume change the pressure chamber (14; 114; 214; 314; 414) for actuating the clutch (60), characterized in that the pressure chamber (14; 114; 214; 314; 414) is at least partially defined by a deformable elastic element (20; 120, 220, 320, 420).

A clutch actuating device (10; 100; 200; 300; 400) according to claim 1, characterized in that said pressure chamber (14; 114; 214; 314; 414) is further controlled by an actuating piston (12; 112; 212; 312; 412). is limited, which is coupled to the coupling (60).

A clutch actuating device (10; 100; 200; 300; 400) according to claim 2, characterized in that the pressure chamber (14; 114; 214; 314; 414) is further supported by a housing member (18; 118; 218; 318; 418). is limited, which movably guides the actuating piston (12; 112; 212; 312; 412).

4. clutch actuating device (10; 100) according to one of claims 1 to 3, characterized in that the deformable elastic element (20; 120) a bellows spring (16; 116), in particular a Rollbalgfeder (16) or a Torusbalgfeder (116) , is.

A clutch actuating device (10; 100) according to claim 4, characterized in that the Torusbalgfeder (116) is associated with a predetermined spring hardness, with which the actuating piston (112) is biased against the coupling (60).

A clutch actuating device (200; 300) according to any one of claims 1 to 3, characterized in that the deformable elastic element (220; 320) comprises a diaphragm (216; 316), in particular a rolling diaphragm (216) or a cup diaphragm (316) , is.

7. clutch actuating device (200; 300) according to claim 6, characterized in that the membrane

(216; 316) can be brought into contact with a support wall (222; 322).

8. clutch actuating device (400) according to one of claims 1 to 3, characterized in that the deformable, elastic element (420) a the pressure chamber (414) forming torus-shaped hollow body (416) with a ventilation dome (430).

9. clutch actuating device (400) according to claim 8, characterized in that the toroidal hollow body (416) is a rubber spring (424) is attached, which preferably comprises a steel insert.

A clutch operating device (10; 100; 200; 300; 400) according to any one of the preceding claims, characterized in that it is a central release device (10; 100; 200; 300; 400).