GB2219830A - Hydraulic cylinder assembly for clutch control - Google Patents

Hydraulic cylinder assembly for clutch control Download PDF

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Publication number
GB2219830A
GB2219830A GB8820572A GB8820572A GB2219830A GB 2219830 A GB2219830 A GB 2219830A GB 8820572 A GB8820572 A GB 8820572A GB 8820572 A GB8820572 A GB 8820572A GB 2219830 A GB2219830 A GB 2219830A
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GB
United Kingdom
Prior art keywords
bore
rearward
annular
cylinder body
piston
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
GB8820572A
Other versions
GB8820572D0 (en
Inventor
David Curtis Barker
Mark Rei
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Automotive Products PLC
Original Assignee
Automotive Products PLC
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Automotive Products PLC filed Critical Automotive Products PLC
Publication of GB8820572D0 publication Critical patent/GB8820572D0/en
Publication of GB2219830A publication Critical patent/GB2219830A/en
Withdrawn legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
    • F16D25/00—Fluid-actuated clutches
    • F16D25/12—Details not specific to one of the before-mentioned types
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T11/00—Transmitting braking action from initiating means to ultimate brake actuator without power assistance or drive or where such assistance or drive is irrelevant
    • B60T11/10—Transmitting braking action from initiating means to ultimate brake actuator without power assistance or drive or where such assistance or drive is irrelevant transmitting by fluid means, e.g. hydraulic
    • B60T11/26—Reservoirs
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B7/00—Systems in which the movement produced is definitely related to the output of a volumetric pump; Telemotors
    • F15B7/06—Details
    • F15B7/08—Input units; Master units
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
    • F16D25/00—Fluid-actuated clutches
    • F16D25/08—Fluid-actuated clutches with fluid-actuated member not rotating with a clutching member
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
    • F16D25/00—Fluid-actuated clutches
    • F16D25/08—Fluid-actuated clutches with fluid-actuated member not rotating with a clutching member
    • F16D25/088—Fluid-actuated clutches with fluid-actuated member not rotating with a clutching member the line of action of the fluid-actuated members being distinctly separate from the axis of rotation
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
    • F16D25/00—Fluid-actuated clutches
    • F16D25/08—Fluid-actuated clutches with fluid-actuated member not rotating with a clutching member
    • F16D2025/081—Hydraulic devices that initiate movement of pistons in slave cylinders for actuating clutches, i.e. master cylinders

Landscapes

  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Transportation (AREA)
  • Hydraulic Clutches, Magnetic Clutches, Fluid Clutches, And Fluid Joints (AREA)

Abstract

A hydraulic cylinder assembly (12) includes a plastic cylinder body (32) open at its forward end (32a) and having an end wall (32b) at its rearward end and defining a cylindrical bore (32c) extending from the open forward end to the end wall; a piston (34) mounted for reciprocal sliding movement in the bore; a push rod (36) coupled to the piston and extending out of the open forward end of the cylinder body; and spring means (38) interposed between the end wall of the cylinder body and the piston. The spring means comprises metallic front and rear coil springs (48,46) having adjacent ends seated in an annular plastic coupler member (50). As the spring assembly expands and contracts in response to actuation of the cylinder assembly, the plastic coupler member maintains the springs in precise axial alignment and precludes buckling and consequent scouring of the plastic surface of the cylinder bore by the high carbon steel of the springs and minimizes the stresses developed within the springs during the cycling of the apparatus. <IMAGE>

Description

HYDRAULIC CYLINDER ASSEMBLY Background of the Invention This invention relates to hydraulic cylinder assemblies.
The present invention has general application to a wide variety of hydraulic cylinder assemblies and has particular application in a clutch hydraulic control system for a motor vehicle. A typical hydraulic cylinder assembly includes a cylinder body defining a cylinder bore, a piston mounted for reciprocal sliding movement in the bore, and spring means extending between an end wall of the cylinder body and the piston to selectively bias and control the movement of the piston and the associated push rod.It is important that the spring not undergo any significant extent of buckling during its compression and expansion during the course of operation of the cylinder assembly since such buckling particularly in the case of a relatively long metal spring operating in a plastic cylinder body, can have the effect of scuffing or scouring the wall of the cylinder body and this scuffing or scouring can ultimately result in derogation of the elastomeric seal mounted on the piston with consequent leakage in the cylinder assembly and derogation of the performance of the cylinder assembly.
Summary of the Invention This invention is directed at the provision of an improved hydraulic cylinder assembly.
More specifically, this invention is directed to the provision of a hydraulic cylinder assembly in which buckling of the spring and consequent scouring of the cylinder bore is substantially eliminated.
The hydraulic cylinder assembly of the invention is of the type including a cylinder body open at its forward end and having an end wall at its rearward end and defining a cylindrical bore extending from the open forward end to the end wall; a piston mounted for reciprocal sliding movement in the bore; a push rod connected to the piston and extending out of the forward end of the cylinder body; and spring means positioned within the cylinder bore for coaction with the piston.According to the invention, the spring means includes a rearward coil spring positioned in the bore with its rearward end seated against the end wall of the cylinder body, a forward coil spring positioned in the bore with its forward bore seated against the rearward end of the piston, and an annular coupler mounted for reciprocal sliding movement in the bore between the springs and defining a rearward annular seat seating the forward end of the rearward spring and a forward annular seat seating the rearward end of the forward spring. This arrangement, replacing a single long spring, substantially eliminates buckling of the spring and thereby substantially eliminates scuffing or scouring of the cylinder wall and the consequent damage to the seal and derogation of the performance of the cylinder assembly.
According to a further feature of the invention1 the cylinder body is formed of a plastic material, the springs are formed of a metallic material, and the coupler is formed of a plastic material. This arrangement allows the superior performance characteristics of a metal spring to be utilized in a plastic cylinder body without danger of scuff ing or scouring of the bore of the cylinder body.
According to a further feature of the invention, the coupler includes an annular axially extending main body portion and an annular rib portion extending radially outwardly from the main body portion at a central axial location spaced axially from the forward and rearward ends of the main body portion, and the forward and rearward annular seats are defined at the forward and rearward annular side faces of the rib portion. This coupler construction provides a convenient and inexpensive means of providing the required annular seats for the adjacent ends of the forward and rearward springs.
According to a further feature of the invention, the cylinder body defines a central fluid opening in the end wall communicating with the bore and the rearward spring is positioned at its rearward end on an annular seat defined on the end wall in concentric surrounding relation to the fluid opening. This specific arrangement provides a convenient, compact, and efficient package for the hydraulic cylinder assembly.
In one embodiment of the invention, the rib portion of the coupler defining the forward and rearward annular seats for the springs guides slidably at its radially outer annular periphery on the inner surface of the bore, and in another embodiment of the invention the coupler further includes a radially outer annular portion joined to the radially outer annular periphery of the rib portion and extending axially forwardly and rearwardly from the rib portion with the outer periphery of this outer annular portion guiding on the inner surface of the bore.
Brief Description of the Drawings FIGURE 1 is a somewhat schematic partially cross-sectional view of a hydraulic master and slave cylinder assembly embodying a spring assembly according to the invention; FIGURE 2 is a top view of the slave cylinder of Figure 1; FIGURE 3 is an end view of the slave cylinder; FIGURE 4 is a detail view taken within the circle 4 of Figure 1; and FIGURE 5 is a detail view showing a modified form of invention spring assembly.
Detailed Description of the Preferred Embodiments The invention hydraulic cylinder assembly is seen in Figure 1 as part of a master and slave cylinder assembly for control of the clutch of a manual transmission motor vehicle. The master and slave cylinder assembly seen in Figure 1 includes a master cylinder assembly 10, a slave cylinder assembly 12, and a conduit 14.
Master cylinder assembly 10 includes a master cylinder body 16 formed of a suitable plastic material and including an integral reservoir 18. Master cylinder body 16 is open at one end 16a and has an end wall 16b at its other end and defines a cylindrical master cylinder bore 16c extending from the open end 16a to the end wall 16b. A plastic piston 20 is mounted for reciprocal sliding movement in bore 16c and carries an annular elastomeric seal 22 for sealing coaction with the bore 16c as the piston moves reciprocally within the bore. A coil spring 24, formed of a high carbon steel, seats at one end on an annular seat defined on end wall 16b in concentric surrounding relation to a central discharge port 16d and seats at its other end on an annular seat defined by the piston. Master cylinder body 16 further defines flange means 16e and 16f for mounting the master cylinder in the firewall 26 of the vehicle with the master cylinder push rod 28 extending out of the open end 16a of the master cylinder body for connection at its free end 28a to the clutch pedal arm 30 of the motor vehicle.
Slave cylinder assembly 12 includes a slave cylinder body 32, a piston 34, a push rod 36 and a spring assembly 38. Slave cylinder body 36 is formed of a suitable plastic material and is open at its forward end 32a and includes an end wall 32b at its rearward end. Cylinder body 32 defines a cylindrical bore 32c extending from the open forward end 32a to end wall 32b and further includes an inlet port 32d formed centrally in end wall 32b. Cylinder body 32 further includes flange means 32e and 32f for mounting the cylinder body in a suitable bulk head or mounting plate 40 of the vehicle adjacent the vehicle clutch.
Piston 34 is mounted for reciprocal sliding movement in bore 32c and is preferably formed of a suitable plastic material. Piston 34 includes a forward portion 34a defining a forwardly opening socket 34b, a land portion 34c, and a rearward nose portion 34d coacting with land portion 34c to define an annular seal groove 34e. An annular elastomeric seal 42 is positioned in seal groove 34e for sealing, sliding coaction with bore 32c. Push rod 36 includes a spherical rearward end 36a pivotally received in socket 34b of piston 34 and is received at its forward free end 36b in a suitable socket portion defined at the free end of a clutch release lever 43. Slave cylinder assembly 12 further includes an annular insert 44 embedded in the open free end of the cylinder body and carrying a snap ring 45 defining the extreme forward position of piston 34.
Spring assembly 38 includes a rearward spring 46, a forward spring 48 and a coupler member 50.
Springs 46 and 48 are of a coil configuration and are formed of a high carbon steel. Coupler member 50 is formed of a suitable plastic material and includes an annular axially extending main body portion 50a and an annular rib portion 50b extending radially outwardly from the main body portion 50a at a central axial location spaced axially from the forward and rearward ends of the main body portion 50a. Rib portion 50b defines a rearward annular seat 50c and a forward annular seat SOd and the outer annular periphery 50e of the rib portion guides slidably on the inner surface of bore 32c. Rearward spring 46 seats at its rearward end on an annular seat 32g defined on end wall 32b in concentric surrounding relation to inlet port 32d and seats at its forward end against the annular seat 50e defined by coupler member rib portion 50b.Forward spring 48 seats at its forward end on an annular seat 34f defined on the rearward nose portion 34d of piston 34 and seats at its rearward end on the annular seat 50d defined by the rib portion 50b of coupler member 50.
Conduit 14 extends between the discharge port ltd of master cylinder 10 and the inlet port 32d of slave cylinder 12 so that hydraulic fluid under pressure is delivered from master cylinder 10 to slave cylinder 12 in response to pivotal movement of clutch pedal arm 30. As the pressure fluid enters the bore of the slave cylinder the slave cylinder piston is moved forwardly to move push rod 36 forwardly to pivot clutch control lever 44 and disengage the clutch in known manner. Following shifting of the manual transmission of the vehicle, the clutch pedal is released and push rod 36 is moved rearwardly under the force of the clutch diaphragm spring to move slave cylinder piston 34 rearwardly and compress coil springs 46 and 48.
During the expanding and contracting movement of the coil springs 46 and 48, coupler member 50 guides at its outer periphery along the inner surface of the cylinder bore and maintains the springs 46 and 48 in precise alignment within the bore and out of contact with the bore. Since the only contact between the spring assembly and the bore is as between the plastic material of rib portion 50b of coupler member 50 and the inner surface of the bore, there is no scouring or scuffing of the bore such as might otherwise occur in the case of a single long spring interposed between the piston and the end wall of the slave cylinder.
Specifically, a single long spring interposed between the piston and the end wall of the cylinder has a tendency of buckling with the result that the single long spring may scour or scuff the cylinder bore and ultimately cut the seal 42 with consequent derogation of the function of the cylinder assembly. The invention spring assembly is especially efficacious with cylinder assemblies requiring a relatively long stroke since long stroke cylinder assemblies require a long spring and this long spring exacerbates the wall scuffing problem associated with buckling of the spring.
As disclosed in Patent No. 4,599,860 assigned to the assignee of this invention, the master cylinder, slave cylinder and interconnecting conduit - are preferably filled with hydraulic fluid and the prefilled assembly is thereafter shipped to the motor vehicle manufacturer for installation on the motor vehicle during the vehicle assembly process to provide a master and slave cylinder assembly for control of the clutch of the vehicle.
An alternate form of invention spring assembly is seen in Figure 5. In the Figure 5 embodiment, the plastic coupler member 60 includes an annular inner axially extending main body portion 60a, an annular rib portion. 60b extending radially outwardly from main body portion 60a at a central. axial location spaced axially from the forward and rearward ends of main body portion 60a, and a radially outer annular portion 60c joined to the radially outer annular periphery of rib portion 6Ob and extending axially forwardly and rearwardly from the rib portion.The front end of spring 46 seats on an annular seat 60d defined on the rear annular face of rib portion 60b, the rear end of spring 48 seats on an annular seat 60e defined on the front face of rib portion 60b, and the outer periphery of outer annular portion 60c guides slidably on slave cylinder bore 32c.
As with the embodiment of Figures 1 through 4, the coupler member 60 serves to maintain the springs 46 and 48 in precise alignment within the bore and out of contact with the walls of the bore and the only contact between the spring assembly and the bore is between the plastic material of outer annular coupler member portion 60c and the inner surface of the bore so that no scouring or scuffing of the bore occurs as the springs undergo expansion and contraction in response to actuation of the master and slave cylinder assembly.
The invention hydraulic cylinder assembly will be seen to have many advantages. Specifically, the invention spring assembly precludes scouring or scuffing of the plastic surface of the cylinder bore by the metal spring, thereby avoiding derogation of the seal and consequent derogation of the performance of the cylinder assembly; the invention spring assembly maintains the coil springs in precise axial alignment during the operation of the cylinder assembly so as to maximize the effectiveness of the springs and minimize the stresses developed within the springs; and the invention spring assembly, by allowing two small springs to be utilized in place of one long spring, provides economies of scale by allowing a higher quantity of small springs to be produced at a low price reflecting the high volume or springs being utilized.
Whereas preferred bodLments of the invention have been illustrated and described in detail it will be apparent that various changes may be made in the disclosed embodiments without departing from the scope or spirit of the invention4

Claims (11)

Claims
1. A hydraulic cylinder assembly comprising: A) a cylinder body open at its forward end, having an end wall at its rearward end, and defining a cylindrical bore extending from said open forward end to said end wall; B) a piston mounted for reciprocal sliding movement in said bore; C) a push rod connected to said piston and extending out of said open forward end of said cylinder body; D) a rearward coil spring positioned in said bore with its rearward end seated against said end wall; E) a forward coil spring positioned in said bore with its forward end seated against the rearward end of said piston; and F) an annular coupler mounted for reciprocal sliding movement in said bore between said springs and defining a rearward annular seat seating the forward end of said rearward spring and a forward annular seat seating the rearward end of said forward spring.
2. A hydraulic cylinder assembly according to claim 1 wherein: G) said cylinder body is formed of a plastic material; H) said springs are formed of a metallic material; and I) said coupler is formed of a plastic material.
3. A hydraulic cylinder assembly according to claim 1 wherein: G) said coupler includes an annular axially extending main body portion and an annular rib portion extending radially outwardly from said main body portion at a central axial location spaced axially from the forward and rearward ends of said main body portion; and H) said forward and rearward axial seats are defined at the forward and rearward annular side faces of said rib portion.
4. A hydraulic cylinder assembly according to claim 3 wherein: I) said rib portion guides at its radially outer annular periphery on the inner surface of said bore.
5. A hydraulic cylinder assembly according to claim 3 wherein: I) said coupler further includes a radially outer annular portion joined to the radially outer annular periphery of said rib portion and extending axially forwardly and rearwardly from said rib portion; and J) the outer periphery of said outer annular portion guides on the inner surface of said bore.
6. A hydraulic cylinder assembly according to claim 1 wherein: G) said cylinder body defines a central fluid opening in said end wall communicating with said bore; and B) said rearward spring is positioned at its rearward end on an annular seat defined on said end wall in concentric surrounding relation to said fluid opening.
7. A hydraulic master and slave cylinder assembly comprising: A) a master cylinder including a master cylinder body open at one end and having an end wall at its other end and defining a cylindrical master bore extending from said open end to said end wall, a master piston mounted for reciprocal sliding movement in said master bore, and a push rod extending into said open end of said master cylinder body for connection to said master piston; B) a slave cylinder including a slave cylinder body open at one end and having an end wall at its other end and defining a cylindrical slave -bore extending from said open end to said end wall, a slave piston mounted for reciprocal sliding movement in said slave bore, and a push rod extending into said open end of said slave cylinder body for connection to said slave piston;; C) a conduit for connection between a discharge port in said master cylinder body and an inlet port in said slave cylinder body; and D) spring means in one of said bores and including a first coil spring positioned in said one bore and seated at one end against the cylinder body end wall, a second coil spring positioned in said one bore and seated at one end against the corresponding piston, and an annular coupler member slidably mounted in said one bore between said springs and defining a first annular seat for seating the other end of said first coil spring and a second annular seat for seating the other end of said second coil spring.
8. A hydraulic master and slave cylinder assembly according to claim 7 wherein: E) said one bore is said slave bore.
9. A hydraulic master and slave cylinder assembly according to claim 7 wherein: E) said cylinder body is formed of a plastic material; F) said springs are formed of a metallic material; and I) said coupler member is formed of a plastic material.
10. A clutch control mechanism comprising: A) a clutch release lever adapted for actuation of the clutch release mechanism; and B) a slave cylinder adapted to receive pressure fluid from an associated master cylinder and including; 1) a cylinder body open at its forward end and having an end wall at its rearward end and defining a cylindrical bore extending from said open forward end to said end wall, 2) a piston mounted for reciprocal sliding movement in said bore, 3) a push rod connected to said piston and extending out of said open forward end of said cylinder body for connection to said clutch release lever, 4) a rearward coil spring positioned in said bore with its rearward end seated against said end wall, 5) a forward coil spring positioned in said bore with its forward end seated against the rearward end of said piston, and 6) an annular coupler mounted for reciprocal sliding movement in said bore between said spring and defining a rearward annular seat seating the forward end of said rearward spring and a forward annular seat seating the forward end of said forward spring.
11. A clutch control mechanism according to claim 10 wherein: C) said coupler includes an annular axially extending main body portion and an annular rib portion extending radially outwardly from said main body portion at a central axial location spaced axially from the forward and rearward end of said main body portion; and D) said forward and rearward annular seats are defined at the forward and rearward annular side faces of said rib portion.
GB8820572A 1988-06-16 1988-08-31 Hydraulic cylinder assembly for clutch control Withdrawn GB2219830A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US20670188A 1988-06-16 1988-06-16

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Publication Number Publication Date
GB8820572D0 GB8820572D0 (en) 1988-09-28
GB2219830A true GB2219830A (en) 1989-12-20

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GB8820572A Withdrawn GB2219830A (en) 1988-06-16 1988-08-31 Hydraulic cylinder assembly for clutch control

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102004045100A1 (en) * 2004-09-17 2006-03-23 Audi Ag Damper for damping pressure vibrations in hydraulic system, has single piece housing with working chamber and piston positionable in working chamber using spring units that axially support itself at cover wall and base wall
CN105465220A (en) * 2014-07-14 2016-04-06 舍弗勒技术股份两合公司 Clutch hydraulic cylinder and shell structure thereof

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB405660A (en) * 1932-08-09 1934-02-09 George Herbert Dowty Improvements relating to shock absorber struts for aircraft
GB690459A (en) * 1950-08-14 1953-04-22 Kronprinz Ag Fur Metallindustr Improvements in and relating to hydraulic shock absorbers
US3686866A (en) * 1967-12-11 1972-08-29 Midland Ross Corp Bleeding seal
EP0095403A1 (en) * 1982-05-20 1983-11-30 Allied Corporation Tandem master cylinder

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB405660A (en) * 1932-08-09 1934-02-09 George Herbert Dowty Improvements relating to shock absorber struts for aircraft
GB690459A (en) * 1950-08-14 1953-04-22 Kronprinz Ag Fur Metallindustr Improvements in and relating to hydraulic shock absorbers
US3686866A (en) * 1967-12-11 1972-08-29 Midland Ross Corp Bleeding seal
EP0095403A1 (en) * 1982-05-20 1983-11-30 Allied Corporation Tandem master cylinder

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102004045100A1 (en) * 2004-09-17 2006-03-23 Audi Ag Damper for damping pressure vibrations in hydraulic system, has single piece housing with working chamber and piston positionable in working chamber using spring units that axially support itself at cover wall and base wall
CN105465220A (en) * 2014-07-14 2016-04-06 舍弗勒技术股份两合公司 Clutch hydraulic cylinder and shell structure thereof
CN105465220B (en) * 2014-07-14 2020-07-31 舍弗勒技术股份两合公司 Clutch hydraulic cylinder and shell structure thereof

Also Published As

Publication number Publication date
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