WO1991011626A1

WO1991011626A1 - A mounting for a member such as a hydraulic cylinder

Info

Publication number: WO1991011626A1
Application number: PCT/EP1990/001779
Authority: WO
Inventors: Boris Kopacin
Original assignee: Automotive Products France S.A.
Priority date: 1990-01-25
Filing date: 1990-10-16
Publication date: 1991-08-08
Also published as: FR2657401A1; FR2657401B1

Abstract

The mounting couples a hydraulic cylinder (10) to a dished sheet metal mounting element (17) on a vehicle bulkhead. The mounting comprises a retaining element (16) on the cylinder (10), an aperture (49) in the mounting element (17) through which part of the cylinder passes and a surface (29) on the cylinder (10) which, after relative rotary movement between the cylinder and mounting element causes the cylinder, mounting element and retaining element to be held firmly together with the retaining element (16) inhibiting separation thereof. The retaining element (16) and mounting element (17) are initially relatively rotatable to inhibit axial separation of the retaining element and mounting element. Also the cylinder (10) and retaining element (16) have surfaces (29, 38) thereon which co-operate during subsequent relative rotational movement between the cylinder (10) and the retaining element (16).

Description

A MOUNTING FOR A MEMBER SUCH AS A HYDRAULIC CYLINDER

The invention relates to a mounting for a member such as a hydraulic cylinder and is particularly, but not exclusively concerned with the mounting of a

hydraulic master cylinder onto a sheet or plate-like part comprising or associated with a bulkhead or firewall of a vehicle.

A mounting structure for coupling a hydraulic

cylinder of a motor vehicle to a bulkhead is

described m our US Patent No. (Ref. A.1964). The mounting involves the use of a resilient gasket to provide frictional resistance to the removal of the installed master cylinder from an aperture in the bulkhead and the use of small pyramidal protuberances which provide an interference fit against an edge of the aperture. Whilst such a mounting is generally satisfactory, it is necessary to apply a manual axial load to the master cylinder during assembly to compress the resilient gasket. Whilst the pyramidal protuberances assist in resisting rotation of the master cylinder once assembled on the bulkhead, they also resist rotation of the master cylinder during assembly. An object of the present invention is to provide a m ounting which provides both easier

assembly and also a more positive resistance to relative rotation between the cylinder and the bulkhead once assembly is complete.

According to one aspect of the invention there is provided a mounting which, in use, couples a first member in the form of a hydraulic cylinder to a sheet or plate-like second member forming part of a

vehicle, the mounting comprising a retaining element on one of or between the first and second members, an aperture in the second member through which the first member passes and a surface on the first member which, after relative rotary movement between the first and second members, causes the first and second members and retaining element to be held firmly together with the retaining element inhibiting separation of the first and second members, the retaining element and second member being initially relatively rotatable to inhibit axial separation of the retaining element and second member and said first member and retaining element having surface portions thereon which co-operate during subsequent relative rotational movement between the first member and the retaining element.

Such an arrangement provides a very positive form of retention of the hydraulic cylinder in the sheet or plate-like second member, typically a bulkhead, as well as providing relatively easy assembly. It is envisaged that the mounting may be used in alternative applications and, in accordance with a further aspect of the invention there is provided a mounting for coupling the first member to a sheet or plate-like second member, the mounting comprising a retσ.ining element on the first member, an aperture in the second member through which the first member passes and a surface on the first member which, aftearelative rotary movement between the first and second members causes the first and second members and retaining element to be held firmly together with the retaining element inhibiting separation of the first and second members, the retaining element and second member being initially relatively rotatable to inhibit axial separation of the retaining element and second member, and said first member and retaining element having surface portions thereon which cooperate during subsequent relative rotational

movement between the first member and the retaining element.

The following preferred features are applicable to either of the aforesaid aspects of the invention.

Preferably, the retaining element and first member are rotatably fast in one direction during the initial relative rotational movement between the retaining element and the second member. The

relative rotation between the retaining element and second member is preferably effected by rotating the first member and retaining element in unison relative to the second member. In that way, the retaining element can be assembled initially onto the first member, the assembly introduced into the aperture on the second member and by simple rotational movement the first member and retaini ng e l ement can be ax i al l y ret a ined in the second member.

The subsequent relative rotation between the first member and retaining element is preferably effected by rotating the first member relative to the

retaining element, e.g., in the same direction of rotation as the first rotational movement.

The retaining element and the second member

preferably incorporate co-operable stop surfaces which limit the initial relative rotation between the retaining element and the second member. Preferably the stop surface of the second member is an edge section of the aperture. The interengagement of the stop surfaces preferably causes first anti-rotation means on the retaining element to align with second anti-rotation means on the second member. The anti- rotation means may comprise a step on the retaining element and a cut-out formed in an edge of the aperture. Preferably co-operation of the surface portions on the first member and retaining element causes the aligned anti-rotation means to move together thereby inhibiting further relative movement between the second member and retaining element.

Such an arrangement provides a very positive

mechanical resistance to rotation between the

retaining element independent of friction.

The surface on the first member which co-operates with the surface of the retaining element is

preferably a ramp-like surface. Similarly, the surface on the retaining element which co-operates with the surface on the first member may be a ramplike surface. The co-operation of the two ramp-like surfaces produces a cam-like effect causing relative axial movement to take place between the retaining element and the first member. The axial movement is preferably arranged to urge or compress the retaining element firmly against the second member which may be disposed between the retaining element and a flange or the like on the first member.

Preferably, the co-operable surfaces of the first member and the retaining element are circumferentially aligned initially whereby initial relative rotation between the retaining element and the second member can be achieved by effecting relative rotation between the first member and the second member with the co-operable surfaces in interengagement. Means such as axially extending fingers may be provided for initially locating the retaining element circumferentially on the first member with the co-operable surfaces of the first member and retaining element in circumferential alignment.

Co-operable lock means may be provided on the first member and retaining element to lock the two together rotationally at a limit of relative rotational movement between the first member and the retaining element. The lock means may include a protrusion on one of the retaining element and first member and a recess on the other of the retaining element and first member. Preferably, the protrusion is formed on the retaining element. Preferably, two

substantially diametrically opposed recesses may be provided for receiving respective protrusions at the limit of relative rotational movement. The or each recess may include an inclined face which will permit the protrusion to be moved out of the recess at such time as the first member is to be disassembled from the second member.

The surface on the first member which co-operates with the surface on the retaining element may be formed on a projecting part of the first member.

Preferably, the retaining element is annular and may be formed with a radial slit to enable it to be assembled onto the first member. Preferably, the retaining element is moulded from a plastics

material. A plurality of circumferentially spaced surface portions may be provided on the retaining element so as to be co-operable with respective or one or more selected surface portions on the first member. The spaced surface portions are preferably formed on radial projections on the retaining

element. One radial projection may be different from the remaining projection or projections so as to match with a complementary shaped part of the

aperture in the same member. The radial projections are preferably of complementary shape to radial cutouts in the aperture to enable the retaining element to pass through the aperture and then, following initial rotary movement relative to the second member, to be retained behind the second member to prevent axial withdrawal of the retaining element from the aperture. A master cylinder mounting in accordance with the invention will now be described by way of example with reference to the accompanying drawings in which:-

Fig.1 is an elevation shown partly in cross-section of a master cylinder connected to the bulkhead of a vehicle by a mounting in accordance with the

invention,

Fig.2 is a view of part of the cylinder of Fig.1 looking in the direction of arrow II in Fig.1 and detached from the bulkhead,

Fig.3 is an elevation of a retaining element,

Fig.4 is an end view of the retaining element of Fig.3 looking in the direction of arrow IV in Fig.3,

Fig.5 is a view of a mounting end of the master cylinder of Figs.1 and 2 with the retaining element in position,

Fig.6 is an end view of part of a mounting element on the bulkhead showing the contour of an aperture therein, Fig.7 is a cross-section through part of the master cylinder shown in Fig.5 on the line VII - VII showing the retaining element located initially in the aperture illustrated in Fig.6,

Fig.8 is a view similar to Fig.7 but showing the retaining element rotated clockwise to a position in which it is located behind the mounting element defining the aperture,

Fig.9 is an end view of the master cylinder shown in Fig.5 looking in the direction of arrow IX in Fig.5 with the retaining element and master cylinder in the Fig.8 position, the mounting element being shown partly broken away,

Fig.10 is a view of part of the arrangement shown in Fig.9 looking in the direction of arrow X in Fig.9, the mounting element being shown partly in cross- section,

Fig.11 is a view similar to Fig.9 but showing the master cylinder rotated anti-clockwise as viewed in Fig.9 relative to the retaining element and Fig.12 is a view of part of the arrangement shown in Fig.11 looking in the direction of arrow XII in

Fig.11.

A master cylinder 10 (constituting the aforesaid first member) has a body 12 defining a bore 13 for a piston (not shown). The components of the master cylinder are similar to that shown in our co-pending French Patent Application No. (Ref.A2340) and will not be described herein.

The body 12 has a mounting flange 14 and projections

15 which co-operate with an annular retaining element

16 and a dished sheet metal mounting element 17 to enable the master cylinder to be supported by a vehicle bulkhead or firewall 18. An annular seal 19 sealingly locates on the bulkhead and has internal sealing edges 20, 22 which respectively sealingly engage the mounting flange 14 and an annular wall 23 of the body 12.

The flange 14 is formed with two locking recesses 24, 25 (see Figs.2, 9 and 12). Each recess 24, 25 comprises a vertical face 26 inclined to a diametral line D, a flat bottomed section 27 and an inclined section 28. As shown in Fig.9, the locking recesses 24, 25 lie on opposite sides of the diametral line D. The projections 15 each include a ramp surface 29 leading from a circumferential flat surface 30 and terminating at a lip 32. The surface 30 and lip 32 are parallel with the flange 14.

The retaining element 16 comprises a ring preferably of plastics material. The ring has four radial projections, three projections 33 of which are identical and a fourth projection 34 of which extends further radially than the projections 33. The left- hand edge of the retaining element 16 as viewed in Fig.3 is formed with four equi-spaced protrusions 35 which lie midway between the projections 33, 34.

Stop surfaces 36 are formed by V-shaped formations 37 extending axially to the right from the left-hand edge of the retaining element. The V-shaped

formations are formed at corresponding ends of the projections 33, 34. Each of the projections 33, 34 extends axially for part of the axial length of the retaining element and defines a ramp surface 38 extending from its associated V-shaped formation 37. The ramp surface 38 terminates at a circumferentially extending flat surface 39. Each projection has a circumferential outer surface 40 and has a part frusto-conical surface 42 extending between the outer surface 40 and the ramp and flat surfaces 38, 39. Each projection also has a part-annular surface 43 formed with a part-cylindrical anti-rotation step 44. Four axially extending fingers 45 are provided on the right-hand edge of the retaining element as viewed in Fig.3 opposite the respective protrusions 35. The retaining element is formed with a slit 46 which passes through one of the protrusions 35 and its opposed finger 45.

The retaining element 16 is located on a cylindrical section 21 of the cylinder 10 between the flange 14 and the projections 15. The ring is opened out to enable it to slip over the projections 15 and it then snaps into position on the cylindrical section 21 as shown in Fig.5. In the position shown in Fig.5, the larger projection 34 on the retaining element 16 is aligned with an outlet connection 47 of the master cylinder 10. In the position shown in Fig.5, the ramp surfaces 29 of the projections 15

circumferentially align with and overlie the ramp surfaces 38 of the projections 33, 34 and the lips 32 of the projections 15 overlie parts of the flat surfaces 39 of the projections 33, 34. The fingers 45 extend alongside axially extending edges 48 of the projections 15. In that way, the retaining ring is initially held substantially in circumferentially fixed relation with the master cylinder 10. As shown in Fig.6, the dished mounting element 17 is formed with an aperture 49 which is of substantially complementary shape to the outer periphery of the retaining element 16. The aperture includes three cut-out sections 50 which correspond generally to the radial projections 33 and a larger cut out section 52 which corresponds to the radial projection 34.

Midway between the sections 50, 52 are four semicircular cut-outs 53.

With the retaining element in position on the master cylinder as shown in Fig.5, the assembly is

introduced axially into the aperture 49 as shown in Fig.7. In Fig.7, the clearance between the aperture 49 and the retaining element 16 is shown slightly larger than it would be in practice for the purposes of illustration. It will be noted that the radial projections 33, 34 will pass freely through the sections 50, 52 of the aperture and the axial

movement of the assembly into the aperture is

continued until the flange 14 abuts the dished mounting element 17 as shown in Fig.10. The

assembled retaining element and master cylinder are then rotated clockwise as viewed in Figs.7 and 8 until the stop surfaces 36 abut inclined stop edges 54 of the sections 50, 52 as shown in Fig.8. Rotational force is transmitted from the master cylinder 10 to the retaining element 16 through ramp surfaces 29, 38. In the Fig.8 position, the anti- iotation steps 44 align axially with the semi- circular cut-outs 53. The interengagement of the stop surfaces 36 and the stop edges 54 prevent any further clockwise rotation of the retaining element 1 6 . In the pos i t i on shown in Fi gs . 8 to 1 2 , the rad i al projections 33, 34 lie behind the dished mounting eiement 17 and prevent axial withdrawal of the master cylinder 10 and retaining element 16 from the aperture 49.

To couple the master cylinder 10 firmly to the dished mounting eiement 17, the master cylinder is turned further clockwise as viewed in Fig.8 (anti-clockwise as viewed in Fig.9) so that the ramp surfaces 29 of the projections 15 ride along the ramp surfaces 38 of the radial projections 33, 34 in cam-like manner thereby causing the retaining element to move axially towards the dished mounting element 17. Such rotary movement of the master cylinder is continued relative to the retaining eiement 16 until the anti-rotation steps 44 enter the semi-circular cut-outs 53 as shown in Figs.11 and 12, (the dished mounting element 17 being shown in broken lines and in part cross- section), the fiat surfaces 30 of the radial projections 15 lie on the flat surfaces 39 of the radial projections 33, 34 and two of the protrusions 35 enter the respective locking recesses 24, 25. The axial distance D (Fig.10) between the part annular surfaces 43 of the projections 33, 34 and the dished mounting element 17 is slightly less than the axial distance that the retaining element 16 tries to move during movement of the projections 15 onto the flat surfaces 39 as shown in Fig.12. That arrangement causes a certain amount of compression of the

retaining eiement 16 and a very firm fixing of the master cylinder to the dished mounting element 17 . The two protrusions 35 which do not enter the locking recesses 24, 25 are compressed into a substantially flat condition against the flange 14. The entry of the protrusions 35 into the locking recesses 24, 25 inhibit further rotational movement of the master cylinder from the Figs.11 and 12 position. Also the location of the anti-rotation steps 44 in the semicircular cutouts 53 mechanically inhibits rotation of the retaining element and the master cylinder

relative to the dished mounting element 17.

The master cylinder 10 can be disassembled from the dished mounting element 17 by manual rotation of the master cylinder in the clockwise direction as viewedin Fig.12. The location of the anti-rotation step 44 in the semi-circular cut-outs 53 mechanically inhibit rotation of the retaining element during such

disassembly rotation until the projections 15 take up the position shown in Fig.10. Thereafter, the antirotation steps 44 can be freed from the semi-circular cutouts 53 and the assembly withdrawn from the aperture.

Although specific reference is made to the use of the dished mounting element 17, the aperture 49 could be formed directly in the sheet or plate material forming the firewall bulkhead 18.

Although specific reference has been made to the use of a mounting in accordance with the invention with master cylinders, the invention could be equally applicable to slave cylinders. Also, it is envisaged that the invention may be used for the mounting of devices other than hydraulic cylinders on a sheet or plate-like support.

Claims

1. A mounting which, in use., couples a first member (10) in the form of a hydraulic cylinder to a sheet or plate-like second member (17) forming part of a vehicle, the mounting comprising a retaining element (16) on one of or between the first and second members, an aperture (49) in the second member ( 17 ) through which the first member passes and a surface (29) on the first member (10) which, after relative rotary movement between the first and second members (10, 17) causes the first and second members and retaining element to be held firmly together with the retaining element (16) inhibiting separation of the first and second members (10, 17) characterised m that the retaining element (16) and second member (17) are initially relatively rotatable to inhibit axial separation of the retaining element and second member, and said first member (10) and retaining element (16) have surfaces (29, 38) thereon which cooperate during subsequent relative rotational

movement between the first member (10) and the retaining element (16).

2. A mounting for coupling a first member to a sheet or plate-like second member (17), the mounting comprising a retaining element (16) on one of or between the first and second members, an aperture (49) in the second member through which the first member passes and a surface on the first member (10) which, after relative rotary movement between the first and second members (10,17) causes the first and second members and retaining element to be held firmly together with the retaining element (16) inhibiting separation of the first and second members (10, 17), characterised in that the retaining element ( 16) and second member (17) are initially relatively rotatable to inhibit axial separation of the

retaining eiement and second member, and said first member (10) and retaining eiement (16) have surfaces (29) 38) thereon which co-operate during subsequent relative rotational movement between the first member (10) and the retaining element (16).

3. A mounting according to Claim 1 or 2

characterised in that the retaining element (16) and first member (10) are rotatably fast in one direction during the initial relative rotational movement between the retaining element (16) and second member

4. A mounting according to Claim 3

characterised in that the relative rotation between the retaining element (15) is effected by rotating the first member (10 ) and retaining element (16) in unison relative to the second member (17).

5. A mounting according to any preceding claim characterised in that the subsequent relative

rotation between the first member (10) and retaining eiement (16) is effected by rotating the first member (10) relative to the retaining element (16).

6. A mounting according to any preceding Claim characterised in that the retaining element (16) and second member (17) incorporate stop surfaces (36, 54) which co-operate to limit the initial relative rotation therebetween.

7. A mounting according to Claim 6

characterised in that the stop surface of the second member (17) is an edge section (54) of the aperture (49) therein.

8. A mounting according to Claim 6 or 7

characterised in that interengagement of the stop surfaces (36, 54) causes first anti-rotation means (44) on the retaining element (16) to align with second anti-rotation means (53) on the second member (17).

9. A mounting according to Claim 8

characterised in that the co-operation of the

surfaces (29, 38 ) on the first member (10) and retaining element (16) causes the aligned antirotation means to move together thereby inhibiting further relative movement between the second member (17) and retaining element (16).

10. A mounting according to any preceding Claim characterised in that the surface (29) on the first member (10) which co-operates with the surface (38) of the retaining eiement is a ramp like surface.

11. A mounting according to any preceding Claim characterised in that the surface (38) on the

retaining element (16) which co-operates with the surface (29) on the first member (10) is a ramp-like surface.

12. A mounting according to any preceding Claim characterised in that the co-operable surfaces (29, 38) of the first member (10) and retaining element (16) are initially circumferentially aligned whereby initial relative rotation between the retaining eiement (16) and the second member (17) can be achieved by effecting relative rotation between the first member (10) and second member (17) with the co operable surfaces (29, 38) in interengagement.

13. A mounting according tc any preceding Claim characterised in that co-operable lock means (24, 25, 35) are provided on the first member (10) and

retaining element (16) to lock together rotationally the first member and retaining element at a limit of relative rotational movement between the first member (10) and retaining element (16).

14. A mounting according to Claim 13

characterised in that the lock means comprises a protrusion (35) on one of the retaining element (16) and first member (10) and a recess (24, 25) on the other of the retaining element (16) and first member

15. A mounting according to any preceding Claim characterised in that the surface (29) on the first member (10) which co-operates with the surface (38) on the retaining element (16) is formed on a

projecting part (15) of the first member (10).

16. A mounting according to Claim 15

characterised in that the projecting part (15) of the first member (10) lies between the co-operable

surface (38) of the retaining element (16) and a projection (45) on the retaining element to hold the retaining element (16) initially at a predetermined circumferential position on the first member (10).

17. A mounting according to any preceding Claim characterised in that the retaining element (16) is

18. A mounting according to Claim 17

characterised in that a plurality of

circumferentially spaced surfaces (38) is provided thereon co-operabie with respective or one or more selected surfaces (29) on the first member (10).

19. A mounting according to Claim 18 or 17 in which the spaced surfaces (38) are formed on radial projections (33, 34) on the retaining element (16).

20. A mounting according to Claim 19 in which one radial projection (34) is different from the remaining projection or projections (33) to match with a complementary shaped part (52) of the aperture (49) in the second member (17).