CN112437848B

CN112437848B - A slave cylinder with a multi-piece housing and a seal ring mounted in the housing; and clutch operating device

Info

Publication number: CN112437848B
Application number: CN201980048111.0A
Authority: CN
Inventors: 米歇尔·雅基
Original assignee: Schaeffler Technologies AG and Co KG
Current assignee: Schaeffler Technologies AG and Co KG
Priority date: 2018-07-17
Filing date: 2019-07-02
Publication date: 2022-10-28
Anticipated expiration: 2039-07-02
Also published as: DE102018120705A1; CN112437848A; WO2020015781A1

Abstract

The invention relates to a slave cylinder (1) for a clutch actuating device of a motor vehicle, comprising a multi-part housing (3) extending concentrically about a longitudinal axis (2) and at least one piston (5) accommodated in the housing (3) in a displaceable manner and defining a pressure chamber (4) together with the housing (3), wherein the housing (3) has a first housing component (6) made of plastic and a second housing component (7) connected to the first housing component (6), wherein, for sealing the pressure chamber (4), a sealing ring (9) is provided which is mounted between the two housing components (6, 7) and is supported by means of a separate support element (8). The invention further relates to a clutch actuating device comprising such a slave cylinder (1).

Description

A slave cylinder with a multi-piece housing and a seal ring mounted in the housing; and clutch operating device

Technical Field

The invention relates to a slave cylinder for a clutch actuating device for a motor vehicle, such as a passenger car, truck, bus or other commercial vehicle, comprising a multi-part housing extending concentrically about a longitudinal axis and at least one piston accommodated in a displaceable manner in the housing and defining a pressure chamber together with the housing. The invention further relates to a clutch actuating device comprising such a slave cylinder.

Background

The applicant is aware of this background art by implementing a slave cylinder 1' as shown in fig. 4. The slave cylinder 1 'has a housing 3' made of metal. In addition to the high production costs of the individual channels provided in the housing 3', the slave cylinder 1' also has the disadvantage of a relatively high overall weight because of the solid metal structure of the housing 3'.

Disclosure of Invention

The object of the present invention is therefore to provide a slave cylinder which can be produced with the lowest possible production costs and weight.

According to the invention, the object is achieved by the following solution: the housing has a first housing part made of plastic and a second housing part connected to the first housing part, wherein a sealing ring is arranged between the two housing parts and is supported by a separate support element for sealing the pressure chamber.

The housing therefore has a particularly low weight. At the same time, it is also possible to mount the two housing components particularly simply.

Further advantageous embodiments are claimed in the dependent claims and are explained in detail below.

The second housing component is preferably constructed of a metallic material. Further preferably, the second housing member is formed of a metal plate (steel plate).

In connection with the two housing components, it is further advantageous if the first housing component is pushed onto the sleeve region of the second housing component with the end face (i.e. axially) contacting the flange region of the second housing component. Thereby aligning the first housing assembly in a secure centered manner with respect to the second housing assembly.

It is also advantageous if a radial recess is provided in the first housing component, in which recess the sealing ring is accommodated in a supported manner by means of a support element. The recess is preferably formed in a direct attachment to the first housing component during the molding process, i.e. during the injection molding process. Alternatively, it is also preferred that the notch is provided in the first housing component in the shape of a groove by means of a cutting process. The production of the housing can thereby be further optimized.

If the support element is designed as a ring (as a support ring), a uniform support is produced in the circumferential direction.

It is also advantageous that the sealing ring is directly received/supported in axial direction between the first housing component and the second housing component.

In this connection, it is further advantageous if the support element is supported on the second housing component (preferably in the flange region of the housing component) on the side facing away from the sealing ring. The notches are therefore preferably open towards an (axial) end face, preferably the end face facing the flange region of the second housing component. The mounting of the sealing ring can thereby be simplified.

A particularly compact construction of the slave cylinder in the radial direction is also possible if the pressure chamber is delimited in the radial direction of the longitudinal axis inwardly by a sleeve region of the second housing component, wherein the sealing ring bears in a sealing manner against the sleeve region. The sleeve region thus forms a radially inner wall of the pressure chamber, and the first housing component forms an outer wall of the pressure chamber, which is arranged outside the inner wall in the radial direction.

The slave cylinder is particularly compact in the axial direction if the support element is mounted in/projects into the coolant channel of the housing.

It is also advantageous here if the support element is provided with radial channels which allow coolant to flow through. The support element is preferably realized in the form of a crown ring, i.e. a circular ring with a plurality of outwardly extending protrusions extending in the circumferential direction.

The manufacturing costs are further reduced when the support element is made of a plastic material.

It is also advantageous if the slave cylinder, in the case of a double slave cylinder, has two pistons which are spaced apart in the radial direction (each of which interacts with a separate pressure chamber). The slave cylinder is thus not only particularly compact, but is also effectively adapted to the operation of a plurality of single-part clutches.

The invention furthermore relates to a clutch actuating device comprising a slave cylinder according to the invention according to at least one of the preceding embodiments and a master cylinder which is or can be hydraulically coupled to the slave cylinder.

In other words, the invention thus achieves a plastic CSC (plastic concentric clutch slave cylinder) comprising a metal flange (second housing component) and a crown-designed bearing ring (support element). The plastic housing (first housing component) containing the metal flange (second housing component) is thus used as a CSC housing, wherein a seal (sealing ring) is fitted in the plastic housing, which is pressed into its designated position by a support ring fitted between the housing (first housing component) and the flange (second housing component). The bearing ring additionally has radial slots (passages, if a crown design is provided), by means of which, in operation, cooling oil can be passed through the coolant passages in the plastic housing to the transmission input shaft.

Drawings

The present invention will be described in detail below with reference to the accompanying drawings.

Fig. 1 is a longitudinal section through a concentric slave cylinder according to a preferred embodiment of the invention, in which the sealing ring mounted in the slave cylinder housing and the supporting element supporting the sealing ring can be clearly seen,

figure 2 a perspective view of the mounted support element of figure 1,

FIG. 3 is a perspective view of a slave cylinder cut in the longitudinal direction as shown in FIG. 1, an

FIG. 4 is a longitudinal cross-sectional view of a slave cylinder of the background art.

Detailed Description

The drawings are merely schematic in nature and are provided to facilitate an understanding of the present invention. Like elements are provided with like reference numerals.

Fig. 1 shows the structure of a Concentric Slave Cylinder 1 (CSC/"Concentric Slave Cylinder") according to the invention. The slave cylinder 1 is designed as a double slave cylinder. The slave cylinder 1 is therefore used in operation to actuate two clutches, for example two partial clutches of a dual clutch, of a motor vehicle drive train. The slave cylinder 1 is embodied in the form of a hydraulic slave cylinder 1. The slave cylinder 1 is embodied in the form of a concentric slave cylinder 1. Accordingly, the slave cylinder 1 has an annular extension/design in its entirety. The slave cylinder 1 is in operation a component of a clutch actuating device of the clutch system and acts in an adjusting manner on the individual clutches of the clutch system. A master cylinder or other actuator is operatively coupled hydraulically to the slave cylinder 1 in order to operate the slave cylinder 1.

The slave cylinder 1 has an annular housing 3. According to the invention, the housing 3 is realized in a multi-part manner in this embodiment. The housing 3 is arranged concentrically around the longitudinal axis 2 as a whole; accordingly, the housing 3 is arranged in such a way that its central/longitudinal axis is concentric with the longitudinal axis 2. The longitudinal axis 2 is the axis with which the transmission input shaft or transmission input shafts of the transmission are arranged in a coaxial manner in operation. In this case, the transmission input shaft preferably passes through the central through hole 23 of the housing 3.

The first housing component 6 of the multi-part housing 3 is manufactured from a plastic material. The first housing component 6 is preferably produced by means of an injection molding process. The second housing component 7 of the housing 3, which is firmly connected to the first housing component 6, is manufactured from a metal material, here steel sheet.

The second housing component 7 has a sleeve region 11 which extends in a tubular manner along the longitudinal axis 2. A flange region 14 of the second housing component 7, which projects outwards in the radial direction, is connected to the axial end of the sleeve region 11. As shown in fig. 3, the two

housing components

6, 7 each have a plurality of fastener positioning holes 24, which are realized in the form of through holes. These fastener locating holes 24 are used to operatively secure the housing 3, preferably to a transmission housing or clutch housing of the powertrain system. The first housing component 6 is pushed onto the sleeve region 11 of the second housing component 7. The first housing component 6 abuts in the axial direction against the flange region 14.

When designed as a double slave cylinder, the slave cylinder 1 has two

slave cylinder units

25a, 25b. The first sub-cylinder unit 25a is arranged radially inside the second sub-cylinder unit 25b. Each

sub-cylinder unit

25a, 25b has a

pressure chamber

4, 26 defined between the housing 3 and the

piston

5, 21. Therefore, the first sub-cylinder unit 25a is implemented by the piston 5, hereinafter referred to as the first piston 5, the housing 3, and the pressure chamber 4 (hereinafter referred to as the first pressure chamber 4) defined between the housing 3 and the first piston 5. The first piston 5 normally acts in a movable manner on a first operating bearing 27 arranged axially outside the housing 3. The second sub-cylinder unit 25b is substantially conformed to the first sub-cylinder unit 25a. Thus, the second sub-cylinder unit 25b is implemented by the second piston 21, the housing 3, and a second pressure chamber 26 defined between the housing 3 and the second piston 21. The second piston 21 acts in a movable manner on a second operating bearing 28 by means of a region which is axially outside the housing 3. In this embodiment, the two operating

bearings

27, 28 are each realized in the form of a radial thrust ball bearing. Like the two

pistons

5, 21, the two operating

bearings

27, 28 are arranged in a mutually spaced manner in the radial direction (relative to the longitudinal axis 2).

It can also be seen that the housing region of the housing 3 which, together with the second piston 21, encloses the second pressure chamber 26 is embodied entirely (i.e. radially on the inside, radially on the outside and axially on the side) by the first housing component 6. The housing area of the housing 3, which together with the first piston 5 encloses the first pressure chamber 4, is realized both by the first housing component 6 and by the second housing component 7. For this purpose, the sleeve region 11 forms a radially inner wall 29 of the housing 3 which delimits the housing region of the first pressure chamber 4. The axial side wall 31 of the housing 3, which delimits the housing region of the first pressure chamber 4, and the radially outer wall 30 are embodied directly by the first housing component 6.

A coolant channel 12 is arranged in the housing 3 in the circumferential region of the slave cylinder 1. The coolant channel 12 has a plurality of segments. The first channel section 18 of the coolant channel 12 (in its channel cross section) is formed/formed by both the first housing component 6 and the second housing component 7. The first channel section 18 extends linearly in a radial direction of the longitudinal axis 2. The first channel section 18 is formed on the one hand by a groove-like depression 16 directly in the first housing component 6. On the other hand, the first channel section 18 is also directly axially covered by the flange region 14. The recess 16 is preferably realized by means of a machining process, for example a milling process, and may alternatively be provided during the shaping of the first housing component 6.

The first channel section 18 merges radially to the outside into a second channel section 19 of the coolant channel 12. The second channel section 19 extends substantially around 90 °, i.e. in the axial direction, in a direction away from the first channel section 18. The second channel section 19 is designed as an axial channel 36 (through-hole) in the flange region 14. The channel 36 is preferably made in the form of a drilled or punched hole.

The first channel section 18 merges radially inwardly into a third channel section 20 of the coolant channel 12. The third channel section 20 is likewise arranged in the second housing component 7, i.e. in the sleeve region 11. In this embodiment, a plurality of radial through-holes 15 arranged side by side in the circumferential direction constitute the third channel section 20. The through-hole 15 is preferably realized in the form of a drilled hole, alternatively also in the form of a punched hole.

Thus, the coolant channel 12 (via the third channel section 20) extends out in the direction of the through-opening 23 on the radial inside 17 of the housing 3; the coolant channel 12 radially outside the

pressure chambers

4, 26 extends on the axial side of the housing 3 (through the second channel section 19) in the direction of the external environment.

According to the invention, a sealing ring 9 is arranged in the radial direction between the two

housing components

6, 7 in order to seal the connection point/first pressure chamber 4 between the first housing component 6 and the second housing component 7. The sealing ring 9 is embodied in the form of an O-ring, i.e. with a circular cross section. The sealing ring 9 is received in a radially arranged notch 10 of the first housing component 6. The notches 10 open out towards the axial side facing the flange region 14. The sealing ring 9 is supported directly by the first housing component 6 towards a first axial side and by an additional support element 8 designed as a support ring towards a second axial side facing away from the first axial side. As is also shown in detail in fig. 2, the support element 8 is supported on the second housing component 7, i.e. on the flange region 14, on its side facing axially away from the sealing ring 9. The flange region 14 has an annular groove 31/groove in which the support element 8 is centrally seated and supported.

The support element 8 is realized substantially in the form of a crown ring. The support element 8 thus has a completely and continuously encircling annular region 32 and a plurality of projections 22 which project in the axial direction from the annular region 32 and are arranged side by side in a uniformly distributed manner in the circumferential direction. The annular region 32 is the region which directly bears against the sealing ring 9 in the axial direction. The projection 22 abuts directly against the second housing component 7. In the circumferential direction between each two adjacent projections 22, a radial channel 13 is formed, through which, in operation, coolant flows. The support element 8 is arranged outside the sleeve region 11 in the radial direction and is mounted in the first channel section 18.

A seal 33 designed as an O-ring is mounted radially outside the first channel section 18 in the axial direction between the first housing component 6 and the second housing component 7. The seal 33 is also mounted in an axial recess 34 of the first housing component 6.

In other words, the invention uses a bearing ring 8 between the CSC housing (housing 3) and the CSC flange (flange area 14). The bearing ring 8 allows the use of a CSC housing (first housing component 6) composed of a polymer, which significantly reduces the overall weight and manufacturing costs (no cutting work is required). The bearing ring 8, by virtue of its design with radial notches (channel 20; of "crowned design"), simultaneously ensures the sealing between the CSC housing 3 and the CSC flange 11 (O-ring groove (notch 10)) and the passage of cooling oil in the CSC housing 3 to the transmission input shaft. In addition, the two-piece design of the "O-ring groove" 17 also simplifies installation of the CSC 1, since the O-ring (sealing ring 9) can be pre-installed in the CSC housing 3, which is composed of a polymer, before the CSC flange 11 with the pre-installed support ring 8 is inserted through the CSC housing 3.

Description of the reference numerals

1. Slave cylinder

2. Longitudinal axis

3. Shell body

4. Pressure chamber

5. Piston

6. First housing assembly

7. Second housing assembly

8. Supporting element

9. Sealing ring

10. Notch opening

11. Sleeve area

12. Coolant channel

13. Channel

14. Flange region

15. Through hole

16. Depressions

17. Inner side

18. First channel segment

19. Second channel segment

20. Third channel segment

21. Second piston

22. Projection

23. Through hole

24. Fastener locating hole

25a first sub-cylinder unit

25b second sub-cylinder unit

26. A second pressure chamber

27. First operation bearing

28. Second operation bearing

29. Inner wall

30. Outer wall

31. Side wall

32. Annular region

33. Sealing element

34. Gap(s)

35. Ditch (A)

36. A channel.

Claims

1. A slave cylinder (1) for a clutch actuating device of a motor vehicle, comprising a multipart housing (3) extending concentrically about a longitudinal axis (2) and at least one piston (5) accommodated displaceably in the housing (3) and defining a pressure chamber (4) together with the housing (3), characterized in that the housing (3) has a first housing component (6) made of plastic and a second housing component (7) connected to the first housing component (6), wherein for sealing the pressure chamber (4) a sealing ring (9) is present which is mounted between the first housing component (6) and the second housing component (7) and is supported by a separate supporting element (8), and the supporting element (8) projects into a coolant channel (12) of the housing (3).

2. The slave cylinder (1) according to claim 1, characterized in that a radial slot (10) is provided in the first housing component (6), in which slot (10) the sealing ring (9) is accommodated in a supported manner by the support element (8).

3. The slave cylinder (1) according to claim 2, characterized in that the support element (8) is designed in the form of a ring.

4. A slave cylinder (1) according to claim 3, characterized in that the support element (8) is supported on the side of the second housing component (7) facing axially away from the sealing ring (9).

5. The slave cylinder (1) according to claim 1, characterized in that the pressure chamber (4) is delimited in the radial direction of the longitudinal axis (2) inwardly by a sleeve region (11) of the second housing component (7), wherein the sealing ring (9) abuts in a sealing manner against the sleeve region (11).

6. The slave cylinder (1) according to any one of claims 1 to 5, characterised in that the support element (8) consists of a plastic material.

7. The slave cylinder (1) according to claim 1, characterized in that the support element (8) is provided with radial channels (13) allowing the passage of coolant.

8. The slave cylinder (1) according to claim 1, characterized in that the slave cylinder (1) has two pistons (5, 21) spaced apart in the radial direction.

9. A clutch operating device comprising a slave cylinder (1) according to any one of claims 1 to 8 and a master cylinder hydraulically coupled with the slave cylinder (1).