WO2021217516A1

WO2021217516A1 - Centering slave cylinder and vehicle clutch

Info

Publication number: WO2021217516A1
Application number: PCT/CN2020/087864
Authority: WO
Inventors: 徐志力; 周冬冬
Original assignee: 舍弗勒技术股份两合公司; 徐志力
Priority date: 2020-04-29
Filing date: 2020-04-29
Publication date: 2021-11-04

Abstract

Disclosed are a centering slave cylinder and a vehicle clutch comprising the centering slave cylinder. The centering slave cylinder has an axial direction (A), a radial direction (R) and a circumferential direction and comprises a housing (1) and at least one piston assembly (2). The housing (1) is provided with a piston assembly installation groove (1c) used for installing the piston assembly (2) and an oil path in communication with the piston assembly installation groove (1c), the piston assembly installation groove (1c) is opened towards the outer side of the axial direction (A) and extends in the axial direction (A) and the circumferential direction, the piston assembly (2) is located in the piston assembly installation groove (1c) and can carry out a reciprocating relative motion in the axial direction (A) relative to the housing (1); and the piston assembly (2) comprises a piston (21) and a needle bearing (23), the needle bearing (23) being connected to the piston (21), such that the piston (21) can abut against a release finger of a clutch by means of the needle bearing (23) under the action of hydraulic oil from the oil path.

Description

Alignment type slave cylinder and vehicle clutch

Technical field

The present invention relates to the field of vehicle clutches, and in particular to a centering type slave cylinder for a vehicle clutch and a vehicle clutch including the centering type slave cylinder.

Background technique

Fig. 1 shows a technical solution of a dual-clutch centering slave cylinder in the prior art. In this technical solution, the dual-clutch centering driven cylinder includes a housing 10, a piston 20, a sealing ring 30 and a ball bearing 40 assembled together.

Specifically, the housing 10 is formed with two mounting grooves 10c with one end opening toward one side in the axial direction (the left side in FIG. 1) and an oil passage (not shown) communicating with the other ends of the two mounting grooves 10c .

The two pistons 20 are respectively installed in the corresponding installation grooves 10c. After the hydraulic oil enters the mounting groove 10c through the oil passage of the housing 10, the piston 20 can be pushed to move relative to the axial side relative to the housing 10 along the axial direction A; after the hydraulic oil returns through the oil passage, the piston Under the action of the release finger of the clutch, 20 performs relative movement along the axial direction A relative to the housing 10 toward the other side of the axial direction (the right side in FIG. 1 ).

Each sealing ring 30 is installed and fixed to the end of the corresponding piston 20 close to the other end of the mounting groove 10c and is located in the mounting groove 10c. The sealing ring 30 is used for sealing between the piston 20 and the mounting groove 10c to ensure During the above relative movement, the hydraulic oil will not leak and cause the oil pressure to drop.

The outer ring of the ball bearing 40 as a release bearing abuts against the axial side end of the piston 20, the inner ring of the ball bearing 40 is used to abut against the release finger (not shown) of the clutch, and the ball bearing 40 is used to The force from the piston 20 is transferred to the clutch release finger to complete the clutch disengagement/engagement work and is used to transfer the force from the clutch release finger to the piston 20 to reset the piston 20.

In the dual-clutch centering type slave cylinder with the above structure, due to the above-mentioned structural layout and the excessive size of the ball bearing 40 itself, the size of the entire dual-clutch centering type slave cylinder is too large, and it is difficult to integrate with the dual-clutch hybrid transmission. The internal dimensions match. In addition, the cost of the ball bearing 40 itself is also relatively high, resulting in a relatively high cost of the entire dual-clutch centering type slave cylinder.

Summary of the invention

The present invention is made in view of the above-mentioned shortcomings of the prior art. The object of the present invention is to provide a new centering type slave cylinder, which is smaller in size and cost-saving compared with the above-mentioned prior art centering type slave cylinder. Another object of the present invention is to provide a vehicle clutch including the above-mentioned centering type slave cylinder.

In order to achieve the above-mentioned purpose of the invention, the present invention adopts the following technical solutions.

The present invention provides a centering driven cylinder having an axial direction, a radial direction, and a circumferential direction. The centering driven cylinder includes a housing and at least one piston assembly. The housing is formed for mounting The piston assembly mounting groove of the piston assembly and the oil passage communicating with the piston assembly mounting groove, the piston assembly mounting groove is open to the outside in the axial direction and extends along the axial direction and the circumferential direction, so The piston assembly is located in the piston assembly mounting groove and is capable of reciprocating relative movement relative to the housing in the axial direction. The piston assembly includes a piston and a needle bearing, and the needle bearing is connected to the housing. The piston is connected so that the piston can abut against the release finger of the clutch via the needle bearing under the action of hydraulic oil from the oil passage.

Preferably, the piston is formed with a bearing mounting groove that is open toward the outside in the axial direction, the needle bearing is installed in the bearing mounting groove, and the piston assembly further includes a retaining ring and an elastic member, and the retaining ring is fixed Where the piston is at least partially located in the bearing mounting groove, the retaining ring is located on the radially inner side of the needle roller bearing and has a gap with at least part of the needle roller bearing in the radial direction to define The needle roller bearing can be displaced toward the radially inner side, and the elastic member abuts against the needle roller bearing and the retaining ring in the axial direction.

More preferably, the retaining ring has a bottom portion that continuously extends along the circumferential direction, the bottom portion is formed with a clamping portion protruding toward the radially inner side, and the piston is formed with a clamping portion that opens toward the radially outer side. A groove, the clamping part cooperates with the clamping groove so that the retaining ring is installed and fixed to the piston.

More preferably, the elastic member is a diaphragm spring, the retaining ring further has two side walls extending radially outward from both end edges of the bottom, and the diaphragm spring is in the axial direction. The first side wall abuts against the two side walls and the inner ring of the needle roller bearing, so that the inner ring abuts against the second side wall of the two side walls.

More preferably, in the radial direction, the second side wall is spaced apart from at least part of the structure of the needle bearing.

More preferably, the centering-type slave cylinder includes two piston assemblies, and the housing forms two piston assembly mounting grooves that cooperate with the two piston assemblies and face each other in the axial direction, so The two piston assemblies are installed in the corresponding piston assembly installation grooves in a line symmetrical manner with respect to the center line of the housing in the axial direction.

More preferably, oil passages respectively communicating with the axially inner ends of the piston assembly mounting grooves are formed in the housing, so that the hydraulic oil can be supplied to each of the piston assembly mounting grooves via the oil passages.内内。 In the groove.

More preferably, the piston assembly further includes a sealing ring installed on the piston for sealing between the piston and the piston assembly mounting groove during the relative movement; The piston has a large diameter portion, a small neck portion, and a flange portion formed as one body, the small neck portion is located between the large diameter portion and the flange portion, and the small neck portion provides the sealing ring Installed so that the sealing ring is clamped between the flange portion and the large diameter portion.

The present invention also provides a vehicle clutch as follows. The vehicle clutch includes the centering driven cylinder described in any one of the above technical solutions.

Preferably, the vehicle clutch is a dual clutch.

By adopting the above technical solution, the present invention provides a novel centering type slave cylinder and a vehicle clutch including the centering type slave cylinder. The center-type slave cylinder uses a needle bearing instead of a ball bearing as a release bearing, and the needle bearing is installed in the bearing installation groove of the piston. In this way, compared with the above-mentioned prior art centering-type slave cylinder, the overall size of the centering-type slave cylinder is greatly reduced and the cost is reduced. At the same time, the needle roller bearing has a centering function, which can well cope with and solve the problem of misalignment of the slave cylinder piston and the clutch under various complicated conditions.

Description of the drawings

Fig. 1 is a schematic cross-sectional view showing a partial structure of a dual-clutch centering type slave cylinder in the prior art.

2a is a schematic cross-sectional view showing a partial structure of a centering slave cylinder according to an embodiment of the present invention; FIG. 2b is an enlarged schematic diagram showing a local structure of the centering slave cylinder in FIG. 2a; 2c is a schematic diagram showing the specific structure of the needle roller bearing, the retaining ring and the diaphragm spring of the centering driven cylinder in FIG. 2a.

Description of Reference Signs

10 Housing 10c Mounting groove 20 Piston 30 Seal ring 40 Ball bearing

1 Housing 1c Piston assembly installation groove

2 Piston assembly 21 Piston 211 Large diameter part 211c Clamping groove 212 Small neck part 213 Flange part 21c Bearing mounting groove

22 sealing ring 22l sealing lip

23 Needle roller bearing 231 Inner ring 232 Outer ring 233 Needle roller 234 Cage

24 Retaining ring 241 Bottom 242 First side wall 243 Second side wall 241p Clamping part

25 diaphragm spring

O Centerline A axis R radial.

Detailed ways

Hereinafter, exemplary embodiments of the present invention will be described with reference to the drawings. It should be understood that these specific descriptions are only used to teach those skilled in the art how to implement the present invention, and are not used to exhaust all possible ways of the present invention, nor are they used to limit the scope of the present invention.

In the present invention, unless otherwise specified, the axial, radial and circumferential directions respectively refer to the axial, radial and circumferential directions of the centering driven cylinder according to the present invention; the center line O is the alignment according to the present invention. The middle line of the housing of the Chinese slave cylinder in the axial direction; the axial outer side refers to the side away from the center line O in Figure 2a, and the axial inner side refers to the side close to the center line O in Figure 2a; the radial direction The outer side refers to the side that is away from the center axis of the centering driven cylinder according to the present invention in the axial direction (for example, the upper side in FIGS. 2a to 2c) in the radial direction, and the radial inner side refers to the radial direction approaching The side of the center axis extending in the axial direction of the centering slave cylinder according to the present invention (for example, the lower side in FIGS. 2a to 2c).

Hereinafter, the structure and function of the centering type slave cylinder according to the first embodiment of the present invention will be described with reference to the accompanying drawings.

As shown in FIGS. 2a to 2c, the centering type slave cylinder according to an embodiment of the present invention includes a housing 1 and two piston assemblies 2. In the overall structure, the two piston assemblies 2 are installed in the corresponding piston assembly installation grooves 1c of the housing 1 in a line-symmetrical manner with respect to the center line O of the housing 1.

Specifically, in this embodiment, as shown in FIGS. 2a and 2b, the housing 1 is formed with two piston assembly mounting grooves 1c for mounting each piston assembly 2. Each piston assembly mounting groove 1c has a substantially circular ring shape, and each piston assembly mounting groove 1c extends a predetermined length along the axial direction A, and the axial outer end is open toward the axial outer side.

The housing 1 is also formed with oil passages (not shown) respectively communicating with the axially inner ends of the piston assembly mounting grooves 1c, so that hydraulic oil can be supplied to each piston assembly installation via the oil passages under the action of the hydraulic mechanism. The axially inner end of the groove 1c.

In this embodiment, the piston assembly 2 is located in the piston assembly installation groove 1c and is capable of reciprocating relative movement relative to the housing 1 in the axial direction A as a whole. The piston assembly 2 includes a piston 21, a sealing ring 22, a needle bearing 23, a retaining ring 24 and a diaphragm spring 25 assembled together.

Specifically, in this embodiment, as shown in FIGS. 2a and 2b, the piston 21 has an annular shape continuously extending along the circumferential direction and includes a large diameter portion 211 and a small neck portion formed integrally in the axial direction A. 212 and flange 213. The large-diameter portion 211 is located on the axially outer side of the small neck portion 212, and the flange portion 213 is located on the axially inner side of the small neck portion 212, so that the small neck portion 212 is located between the large-diameter portion 211 and the flange portion 213. The outer diameter of the large diameter portion 211 is larger than the outer diameter of the flange portion 213, and the outer diameter of the flange portion 213 is larger than the outer diameter of the small neck portion 212. The outer diameter of the large-diameter portion 211 matches the large diameter of the piston assembly mounting groove 1c. The large-diameter portion 211 is also formed with a bearing mounting groove 21 c that opens toward the outside in the axial direction and a clamping groove 211 c for clamping the clamping portion 241 p of the retaining ring 24. The small neck portion 212 is for mounting the seal ring 22 so that the seal ring 22 is clamped between the flange portion 213 and the large diameter portion 211. The flange portion 213 is used to stop the sealing ring 22 and prevent the sealing ring 22 from falling off the small neck 212.

2a and 2b, at the position of the small diameter portion 212, a seal ring mounting groove recessed radially inward is formed on the outer circumferential surface of the piston 21 for installing a seal ring 22, and a seal ring 22 is formed on the inner circumferential surface of the piston 21 The sealing ring mounting groove recessed toward the radially outer side is used for mounting another sealing ring 22. The flange portion 213 protrudes toward both the radially inner side and the radially outer side, so as to stop the two seal rings 22 in the axial direction A.

Further, in the present embodiment, as shown in FIGS. 2a and 2b, the sealing ring 22 is made of elastic material such as rubber and is mounted on the small neck 212 of the piston 21, and can also be vulcanized on the small neck 212. The sealing ring 22 is used to achieve a seal between the piston 21 and the piston assembly mounting groove 1c during the movement of the piston assembly 2 relative to the housing 1. The sealing ring 22 is formed with a sealing lip 221 protruding toward the side wall of the piston assembly mounting groove 1c. The sealing lip 221 is in contact with the side wall of the piston assembly mounting groove 1c, so that a contact seal between the piston assembly 2 and the piston assembly mounting groove 1c is achieved, and the hydraulic oil is prevented from leaking and the oil pressure is reduced.

Further, in this embodiment, as shown in FIGS. 2a to 2c, the needle bearing 23 is installed in the bearing mounting groove 21c, so that the piston 21 can be pressed by the needle bearing 23 under the action of the hydraulic oil from the oil circuit. Connected to the release finger of the clutch, and the needle bearing 23 can also transmit the force from the release finger to the piston 21.

The needle bearing 23 is a thrust bearing and includes an inner ring 231, an outer ring 232, a cage 234, and a plurality of needle rollers 233 assembled together. The inner ring 231 includes an inner ring axial portion extending along the axial direction A and an inner ring radial portion extending from the axially inner end of the inner ring axial portion along the radial direction R toward the radially outer side. The outer ring 232 includes an outer ring axial portion extending along the axial direction A and an outer ring radial portion extending from the axially outer end of the outer ring axial portion along the radial direction R toward the radial inner side. The axial part of the inner ring is opposite to the axial part of the outer ring in the radial direction R, and the radial part of the inner ring is opposite to the radial part of the outer ring in the axial direction A. The cage 234 is located in the space enclosed by the inner ring 231 and the outer ring 232, and is used to hold a plurality of needle rollers 233 evenly distributed in the circumferential direction. Each needle roller 233 has a cylindrical shape, and the center line axis of each of the plurality of needle rollers 233 is along the radial direction R. All the needle rollers 233 can roll in the raceway defined by the inner ring 231 and the outer ring 232.

Further, in this embodiment, as shown in FIGS. 2a to 2c, the retaining ring 24 is fixed to the piston 21 and is at least partially located in the bearing installation groove 21c. The retaining ring 24 is located on the radially inner side of the needle roller bearing 23 and is used to limit the range within which the needle roller bearing 23 can be displaced toward the radially inner side. Due to the centering performance of the centering driven cylinder according to the present invention, the needle roller bearing 23 will produce a centering offset movement in the radial direction R under the reaction force of the clutch release finger, and the retaining ring 24 defines the needle roller bearing 23 The maximum offset in the radial direction R.

The retaining ring 24 has a bottom 241 continuously extending in the circumferential direction and two

side walls

242, 243 extending from both side ends of the bottom 241 toward the radially outer side. The two

side walls

242, 243 include The first side wall 242 extending from the axially inner end and the second side wall 243 extending from the axially outer end of the bottom 241. In addition, for example, by pressing, the bottom 241 is formed with a plurality of engaging portions 241p protruding toward the radially inner side. The plurality of engaging portions 241p and the large-diameter portion 211 of the piston 21 are formed in the bearing mounting groove 21c. The clamping groove 211 c that opens toward the radially outer side is clamped and fitted, so that the retaining ring 24 is installed and fixed to the piston 21.

Furthermore, in this embodiment, as shown in FIGS. 2 a to 2 c, the diaphragm spring 25 is located between the needle bearing 23 and the retaining ring 24. The outer circumferential portion of the diaphragm spring 25 abuts against the radial portion of the inner ring 231 of the inner ring 231 of the needle roller bearing 23, and the inner circumferential portion of the diaphragm spring 25 abuts against the first side wall 242 of the retaining ring 24, so that the needle roller bearing The inner ring axial portion of the inner ring 231 of the 23 abuts against the second side wall 243 of the retaining ring 24. In this way, on the one hand, the needle roller bearing 23 can be limited in the axial direction A; on the other hand, the diaphragm spring 25 makes the inner ring axial part of the inner ring 231 of the needle roller bearing 23 and the second side wall 243 A predetermined frictional force is generated between them, and only when the centering force generated by the force from the clutch release finger is greater than the frictional force, the needle roller bearing 23 generates an offset movement in the radial direction R.

2c, in the case where the needle bearing 23 is centrally mounted on the retaining ring 24, in the axial direction A, the second side wall 243 abuts against the inner ring axial portion of the inner ring 231, and in the radial direction R , The second side wall 243 is spaced apart from the needle bearing 23 (more specifically, the portion of the needle bearing 23 that is radially opposite to the second side wall 243, that is, the needle 233 or the outer ring 232), so as to The radial offset of the needle bearing 23 relative to the retaining ring 24 provides space.

In addition to providing the centering driven cylinder with the above structure, the present invention also provides a vehicle clutch, which includes the centering driven cylinder with the above structure. In the case of the centering slave cylinder with the above structure, the vehicle clutch may be a dual clutch, and the two clutch units of the dual clutch and other structures corresponding to the two piston assemblies 2 are respectively arranged on the shafts of the corresponding piston assemblies 2. To the outside.

It should be understood that the above-mentioned embodiments are only exemplary and are not used to limit the present invention. Those skilled in the art can make various modifications and changes to the above-mentioned embodiments under the teaching of the present invention without departing from the scope of the present invention. In addition, the following description will be given.

(i) Although the centering type slave cylinder using two bearing assemblies 2 is described in the above specific embodiments, the present invention is not limited to this. The centering driven cylinder according to the present invention may include a bearing assembly 2.

(ii) In the prior art centering slave cylinder technical solution shown in FIG. 1, the size of the ball bearing 40 in the axial direction A is approximately 16.95 mm, and the load from the housing 10 in the axial direction A The size of the axial portion of the inner ring facing the inner ring of the ball bearing 40 is 56.15 mm. In contrast, in the technical solution of the centering driven cylinder according to the present invention as shown in FIGS. 2a to 2c, the needle bearing 23 has a size of approximately 4.8 mm in the axial direction A, and the centering driven cylinder is The overall size in the axial direction A is reduced to 32.5mm. It can be seen that the size of the centering slave cylinder according to the present invention is greatly reduced compared to the size of the centering slave cylinder of the prior art, thereby saving installation space.

(iii) In the prior art centering slave cylinder technical solution shown in FIG. 1, due to the requirement for neutrality, the sealing lip of the sealing ring 30 will be severely worn, so the centering type according to the present invention is adopted. The structure of the slave cylinder (including the retaining ring 24 and the diaphragm spring 25) can then effectively reduce the wear of the sealing lip 221 of the sealing ring 22 due to the requirement for neutrality.

Claims

A centering driven cylinder has an axial direction (A), a radial direction (R) and a circumferential direction. The centering driven cylinder includes a housing (1) and at least one piston assembly (2). The housing The body (1) is formed with a piston assembly installation groove (1c) for installing the piston assembly (2) and an oil passage communicating with the piston assembly installation groove (1c), the piston assembly installation groove (1c) ) Open toward the outside of the axial direction and extend along the axial direction (A) and the circumferential direction, and the piston assembly (2) is located in the piston assembly installation groove (1c) and can be in the axial direction ( A) reciprocating relative movement relative to the housing (1), the piston assembly (2) includes a piston (21) and a needle bearing (23), the needle bearing (23) and the piston (21) Connection so that the piston (21) can abut against the release finger of the clutch via the needle bearing (23) under the action of the hydraulic oil from the oil passage.
The centering type slave cylinder according to claim 1, wherein the piston (21) is formed with a bearing mounting groove (21c) that opens toward the outside in the axial direction, and the needle bearing (23) is mounted on the The bearing installation groove (21c), the piston assembly (2) further includes a retaining ring (24) and an elastic member, the retaining ring (24) is fixed to the piston (21) and at least partially located in the bearing installation In the groove (21c), the retaining ring (24) is located on the radial inner side of the needle roller bearing (23) and has a gap with at least part of the needle roller bearing (23) in the radial direction (R) , Used to limit the range within which the needle roller bearing (23) can be shifted toward the radially inner side, and the elastic member abuts against the needle roller bearing (23) and the retaining ring ( twenty four).
The centering driven cylinder according to claim 2, wherein the retaining ring (24) has a bottom portion (241) continuously extending along the circumferential direction, and the bottom portion (241) is formed with a facing diameter A clamping portion (241p) protruding inward and the piston (21) are formed with a clamping groove (211c) that opens toward the radially outer side, and the clamping portion (241p) is connected to the clamping groove ( 211c) fits so that the retaining ring (24) is installed and fixed to the piston (21).
The centering driven cylinder according to claim 3, wherein the elastic member is a diaphragm spring (25), and the retaining ring (24) also has end edges from both sides of the bottom (241). Two side walls extending toward the radially outer side, the diaphragm spring (25) abuts against the first side wall (242) of the two side walls and the roller in the axial direction (A) The inner ring (231) of the needle bearing (23) makes the inner ring (231) abut against the second side wall (243) of the two side walls.
The centering driven cylinder according to claim 4, characterized in that, in the radial direction (R), the second side wall (243) is spaced from at least part of the needle bearing (23). open.
The centering slave cylinder according to any one of claims 1 to 5, wherein the centering slave cylinder includes two piston assemblies (2), and the housing (1) is formed with the The two piston assembly mounting grooves (1c) that are opposite to each other in the axial direction (A) are matched by the two piston assemblies (2), and the two piston assemblies (2) are opposed to the housing ( The center line of 1) in the axial direction (A) is installed in the corresponding piston assembly installation groove (1c) in a line-symmetric manner.
The centering type slave cylinder according to claim 6, characterized in that the housing (1) is formed with oil passages respectively communicating with the axially inner ends of the piston assembly mounting grooves (1c) , So that the hydraulic oil can be supplied into each of the piston assembly installation grooves (1c) via the oil passage.
The centering driven cylinder according to any one of claims 1 to 7, wherein the piston assembly further comprises a sealing ring (22), and the sealing ring (22) is mounted on the piston (21) , Used for sealing between the piston and the piston assembly mounting groove during the relative movement; the piston (21) has a large diameter portion (211) and a small neck portion ( 212) and a flange portion (213), the small neck portion (212) is located between the large diameter portion (211) and the flange portion (213), and the small neck portion (212) is provided for the The sealing ring (22) is installed so that the sealing ring (22) is clamped between the flange portion (213) and the large diameter portion (211).
A vehicle clutch, the vehicle clutch comprising the centering type driven cylinder according to any one of claims 1 to 8.
The vehicle clutch according to claim 9, wherein the vehicle clutch is a dual clutch.