HYDROSTATIC CLUTCH ACTUATOR WITH OVERFLOW

Abstract

The present invention relates to a hydrostatic clutch actuator (1) for a clutch, in particular a wet clutch, of a motor vehicle, wherein the clutch actuator (1) has a drive unit (2, 3), a master cylinder-piston-cylinder unit (4, 5) driven thereby, a hydraulic reservoir (6) fluidically connected to the master cylinder-piston-cylinder unit, and a hydraulic system for actuating the clutch, wherein, by use of the master cylinder-piston-cylinder unit (4, 5), hydraulic medium can be conveyed out of the hydraulic reservoir (6) into the hydraulic system and the hydraulic system can be pressurized, and the hydraulic reservoir (6) has an overflow (10), via which hydraulic medium can be discharged from the hydraulic reservoir (6) and the hydraulic system.

Claims

1. A hydrostatic clutch actuator for a clutch of a motor vehicle, the clutch actuator comprising a drive unit, a master-piston cylinder unit driven by the drive unit, a hydraulic reservoir connected in a fluidic fashion to the master-piston cylinder unit, a hydraulic system for operating the clutch, allowing conveyance of hydraulic medium via the master-piston cylinder unit from the hydraulic reservoir to the hydraulic system and applying pressure upon the hydraulic system, the hydraulic reservoir comprises an overflow by which the hydraulic medium is drainable from the hydraulic reservoir and the hydraulic system.

2. The hydrostatic clutch actuator according to claim 1, wherein the overflow is connected in a fluidic fashion to a collection vessel.

3. The hydrostatic clutch actuator according to claim 1, wherein the overflow is embodied such that any flux of the hydraulic medium through the overflow into the hydraulic reservoir is prevented.

4. The hydrostatic clutch actuator according to claim 1, wherein the overflow comprises an input opening, which is embodied for conducting hydraulic medium from the hydraulic reservoir into the overflow and the overflow comprises an outlet opening which is provided to allow draining the hydraulic medium out of the overflow.

5. The hydrostatic clutch actuator according to claim 4, wherein the input opening is arranged higher than a collection vessel connected to the overflow or that the overflow is blockable by a return valve in an intended position of the clutch actuator.

6. The hydrostatic clutch actuator according to claim 4, wherein the outlet opening comprises a hose connector.

7. The hydrostatic clutch actuator according to claim 4, wherein a tubular line section provided between the input opening and the output opening declines towards the input opening in an intended position of the hydraulic reservoir.

8. The hydrostatic clutch actuator according to claim 1, wherein the overflow is integrated in a cover that closes the hydraulic reservoir.

9. The hydrostatic clutch actuator according to claim 1, wherein the overflow is integrated in a wall of the hydraulic reservoir.

10. The hydraulic clutch actuator according to claim 1, wherein the hydraulic reservoir has a fill opening.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In the following the invention is explained in greater detail based on drawings of several exemplary embodiments. Here shown are:

[0021] FIG. 1 a schematic, perspective illustration of a hydrostatic clutch actuator according to the invention in a first embodiment with two electric rotary drives and two master cylinders in a perspective view,

[0022] FIG. 2 a hydraulic reservoir of the clutch actuator of FIG. 1 alone in a perspective view,

[0023] FIG. 3 a hydraulic reservoir of the clutch actuator of FIG. 1 alone in a cross-section,

[0024] FIG. 4 a schematic, perspective illustration of a hydrostatic clutch actuator according to the invention in a second embodiment with two electric rotary drives and two master cylinders in a perspective view,

[0025] FIG. 5 a hydraulic reservoir of the clutch actuator of FIG. 3 alone in a perspective view and in a cross-section, and

[0026] FIG. 6 a hydraulic reservoir of the clutch actuator of FIG. 1 alone in a cross-section.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] The figures are only of a schematic nature and exclusively serve to understand the invention. Identical elements are marked with the same reference characters. Details of the different embodiments can be combined with each other and/or exchanged for each other.

[0028] FIGS. 1 to 3 show a hydrostatic clutch actuator 1 with two electric drives 2, 3 and two master cylinder housings 4, 5 in a perspective illustration. The master cylinder housing 5 is correctly called cover housing and is de facto independent from the master cylinder housing 4. The clutch actuator 1 serves to operate a clutch, not shown in the figures, for example a wet-running duplex clutch for a motor vehicle.

[0029] Generally the actuation occurs via a hydraulic system, which is also called the hydraulic path, and an actuator device with two slave cylinders, not shown in the figures, either. Master cylinders received in master cylinder housings 3, 4 can each be connected via the hydraulic path to a slave cylinder so that, starting from the master cylinder, a hydraulic power can be transmitted to the slave cylinder. The duplex clutch comprises two pressure plates, which can be axially displaced with the help of an actuating device, particularly the slave cylinder, respectively between an engaged actuating position and a disengaged actuating position.

[0030] The electric drives 2, 3 serve to drive the two master cylinders. The drive 2 is functionally allocated to the master cylinder in the master cylinder housing 3. The drive 3 is functionally allocated to the master cylinder in the master cylinder housing/cover housing 5. The master cylinder housing 5 is a “cover housing” or the like, which protects the interior mechanics of the actuator from influences of the environment.

[0031] Hydraulic medium for the hydraulic system comprising the master and slave cylinders is received in a hydraulic reservoir 6. It can be fed via an interposed unit, for example in the form of a regulating valve or a control valve, to the hydraulic system or drained from the hydraulic system.

[0032] The hydraulic reservoir 6 is a container, perhaps made from plastic or metal, preferably an injection-molded container. In the examples shown an upper bowl 7 and a lower bowl 8 are connected to each other tightly via a welded seam 9. In the embodiment of FIGS. 1 and 2 the upper bowl 7 shows an overflow 10 integrated therewith in one piece. It shows an input opening 11, via which medium can drain from the hydraulic reservoir 6 into the overflow 10, an outlet opening 12 via which medium can drain from the overflow 10, and a line section 13 arranged between the inlet opening 11 and the outlet opening 12. The latter is lightly declined in the direction of the hydraulic reservoir 6 in the intended arrangement of the clutch actuator 1. The outlet opening 12 is embodied as a hose connection with bulges 14 for a clamping connection of a hose, not shown, via which medium draining from the hydraulic reservoir 6 can be fed to the collection tank or oil pan. For the purpose of an easy filling process of the hydraulic reservoir 6 with hydraulic medium its upper bowl 7 is provided with a fill opening, which can be closed with a threaded plug 15.

[0033] FIGS. 4 to 6 show another embodiment of the invention, which is similar to the embodiment of FIGS. 1 and 2 so that in the following only the differences are explained and for the rest reference is made to the embodiment of FIGS. 1 and 2. The upper bowl 7 of the hydraulic reservoir 6 of this embodiment is embodied with a fill opening 16. The wall of the upper bowl 7 surrounding it is provided with an external thread 17, onto which a threaded cover 18 with an internal thread is screwed to close the fill opening 15. The overflow 10 is inserted into the center of the threaded cover 18, comprising a line section 13 with an input opening 11 and an output opening 12. The end of the line section 13 at the output side is also embodied as a hose connector with bulges 14 for clamping a hose. In this embodiment it is advantageous that an additional fill opening is not required because filling occurs via the fill opening 16 by unscrewing the cover 18.

[0034] In the two embodiments shown the overflow 10 is located as high as possible in the hydraulic reservoir. It serves both for draining excess medium from the hydraulic reservoir 6 as well as ventilating and exhausting the hydraulic system in case of pressure fluctuations.

LIST OF REFERENCE CHARACTERS

[0035] 1 clutch actuator [0036] 2 drive [0037] 3 drive [0038] 4 master cylinder housing [0039] 5 master cylinder housing/lid housing [0040] 6 hydraulic reservoir [0041] 7 upper bowl [0042] 8 lower bowl [0043] 9 welding seam [0044] 10 overflow [0045] 11 inlet opening [0046] 12 outlet opening [0047] 13 line section [0048] 14 bulging [0049] 15 threaded plug [0050] 16 fill opening [0051] 17 external thread [0052] 18 threaded cover