GB2024368A

GB2024368A - Clutch plate assembly

Info

Publication number: GB2024368A
Application number: GB7911454A
Authority: GB
Original assignee: Societa Applicazioni Gomma Antivibranti SAGA SpA
Current assignee: Societa Applicazioni Gomma Antivibranti SAGA SpA
Priority date: 1978-07-03
Filing date: 1979-04-02
Publication date: 1980-01-09
Also published as: IT7825266A0; JPH0115728B2; GB2024368B; DE2916254C2; FR2430541A1; FR2430541B1; DE2916254A1; IT1096956B; ES479010A1; JPS5514395A

Abstract

A clutch plate assembly (1) for motor vehicles comprises a hub (2) having a collar (3, 4) which is rotatable with the hub, an intermediate annular body (7) having a plurality of hollow portions (8) on its surface facing the collar (3, 4), in which hollow portions there are vulcanised blocks (11) of an elastomer material, each one being fixed by a pin (13) to the collar (3,4). The assembly includes stops (10) for limiting relative rotation between the intermediate body (7) and the collar (3,4), and a clutch plate (19) torsionally connected by resilient rings (15) and pins (17) to the intermediate body (7). <IMAGE>

Description

SPECIFICATION Clutch plate assembly The invention relates to plate-type clutches for motor vehicles of the type having a clutch plate assembly comprising a hub provided with a collar which is rotatable with the hub, an intermediate annular body which is torsionally connected to the collar by means of interposed resilient means, means for keeping the relative rotation between the intermediate body and the collar within predetermined limits, and a clutch plate which is torsionally connected by elastic means to the intermediate body.

The present invention has the aim of providing a clutch of the specified type which takes up little space in the axial direction, is of simple construction, is easy to assemble and has a long life.

According to the invention a clutch plate assembly comprises a hub having a collar for rotation with the hub; an intermediate annular body which is limitedly rotatable relative and torsionally connected to the collar by interposed resilient means; means for keeping the relative rotation between the intermediate body and the collar within predetermined limits; and a clutch plate torsionally connected by resilient means to the intermediate body; the intermediate annular body having a plurality of hollow portions on its surface facing the collar, and the interposed resilient means comprising a plurality of bodies of an elastomer material, each of which is housed in a corresponding hollow portion and is fixed on one side to the collar and on the other side to the facing wall of the respective hollow portion in the intermediate annular body.

The presence of the bodies of elastomer material, which are housed inside the hollow portions formed in the intermediate annular body, makes it possible to obtain the further advantage of making available resilient means having very good damping properties which leads to a reduction in the transmission of vibrations from the collar to the intermediate body and vice versa and reduces undesirable effects such as, for example, noise.

One example of an assembly according to the invention will now be described with reference to the attached drawings in which: Figure 1 is a cross-section through the clutch plate assembly; Figure 2 is an exploded view of the assembly of Figure 1; and, Figure 3 is a view in the direction of arrow Ill in Figure 1.

The clutch plate assembly 1 comprises a hub 2 provided with two axially spaced annular flanges 3 and 4. Flange 3 is rigidly fixed to hub 2 whilst flange 4 is fixed for rotation with the hub but is able to slide in the axial direction with respect to it. The connection between the flange 4 and the hub 2 is obtained by making use of a bush 5 which is rigidly fixed to the inner part of the flange 4 and is able to slide on the outer surface of hub 2 by means of a splined coupling 6. A circlip 20 prevents the bush 5 from sliding off the hub 2. The space between the two flanges 3 and 4 houses the radially inner portion of a sheet metal disc 7. This inner portion of disc 7 has depressed regions 8, on either side of its central plane, formed by plastically deforming the disc.Regions of depression 8 on one face of the disc 7 alternate with the regions of depression 8 on the other face of the disc 7. This leads to the formation, on each face of the disc, of alternating hollow regions formed by the depressed regions 8 and the raised regions 9 corresponding to the reverse side of the hollow regions 8 formed on the other face of the disc 7.

The flange 3 is provided with two openings 3a which are diametrically opposed. In an identical manner, flange 4 has a pair of openings 4a which are also diametrically opposed. Each one of these openings houses a shaped block 10 which is rigidly fixed to the adjacent face of the disc 7. Each block 10 is fixed to a raised portion 9 on the respective face of the disc. Each hollow region 8 houses a rubber block 11 which extends in the axial direction and is fixed by vulcanization to the bottom wall of the respective hollow region 8. The opposite end of each block 11 has a small metal plate 12 attached to it by vulcanization, the metal plate having a stud 13 rigidly attached to it which extends outwardly in the axial direction. Each stud 13 engages inside a corresponding hole 14 formed in the adjacent annular flange 3 or 4.

The intermediate sheet metal disc 7 has an undeformed outer radial portion, the opposing lateral faces of which each carry an annular ring 1 5 of rubber and which are fixed in place by vulcanization. Each ring 1 5 carries, on its face remote from the sheet metal disc 7, an annular frusto-conical plate 1 6 having a plurality of raised cylindricai projections 1 7. These projections 1 7 engage with two shaped annular parts 18 having a radial annular edge 1 8a on their periphery. The clutch plate 1 9 of the assembly 1 is interposed and fixed between the two radial edges 1 8a of the two parts 1 8.

Between each block 10 and the adjacent circumferential edges of the respective opening 3a or 4a, circumferential play is provided for at each side, as shown by the gap G. The presence of this play makes possible predetermined relative rotation between hub 2 and the intermediate body 7. Connection between the hub and the intermediate body is provided for by the rubber blocks 11.

The special shape of the blocks 11 and the corresponding shape of the radially internal part of the body 7 makes it possible to provide a clutch assembly which has relatively restricted axial dimensions. Furthermore, the rubber blocks 11 have relatively low rigidity characteristics as they operate mainly under shear conditions. This rigidity is, very much lower than that of the rubber annular rings 15 arranged externally of the blocks 11. This arrangement prevents vibrations from being transmitted from the hub 2 to the intermediate body 7 when, for example, the gearbox of the vehicle on which the clutch is mounted is in the neutral position. The rubber blocks 11 are particularly suitable for carrying out this function, in view of the high damping characteristics of the material constituting them.

Furthermore, as a plurality of blocks 11 which are separate from each other are used in place of one single annular ring of rubber material, it is possible to prevent any possible breakage from rapidly spreading to the whole ring, thus leading to rapid failure of the clutch. Flange 4 is arranged in the axial sense in such a way that it exercises a predetermined axial precompression on the adjacent blocks 11: flange 4 is maintained in this axial position by means of a snap ring 20.

Claims

1. A clutch plate assembly comprising a hub having a collar for rotation with the hub; an intermediate annular body which is limitedly rotatable relative and torsionally connected to the collar by interposed resilient means; means for keeping the relative rotation between the intermediate body and the collar within predetermined limits; and a clutch plate torsionally connected by resilient means to the intermediate body; the intermediate annular body having a plurality of hollow portions on its surface facing the collar, and the interposed resilient means comprising a plurality of bodies of an elastomer material, each of which is housed in a corresponding hollow portion and is fixed on one side to the collar and on the other side to the facing wall of the respective hollow portion in the intermediate annular body.

2. An assembly according to claim 1, in which the wall of each hollow portion to which the corresponding end of the respective body of elastomer material is fixed and the facing wall of the collar, to which the other end of the respective body is fixed, are arranged substantially perpendicular to the axis of the assembly.

3. An assembly according to claim 1 or claim 2, in which the collar comprises a pair of axially spaced apart annularflanges and wherein the radially inner part of the intermediate body is interposed between the flanges and has, in each of its faces which face the flanges, a plurality of hollow portions in which the bodies of elastomer material are housed, each body of elastomer material being fixed on one side to the base wall of the respective hollow portion and on the other side to the facing surface of the respective adjacent flange.

4. An assembly according to claim 3, in which the hollow portions which are formed on one face of the intermediate body are arranged circumferentially alternately with the hollow portions formed on the other face, the hollow portions in the one face thus always being arranged axially non-aligned with the hollow portions in the other face.

5. An assembly according to claim 3 or claim 4, in which at least one of the two annular flanges which constitute the collar is retained on the hub by means of a releasable fastener.

6. An assembly according to claim 5, in which the annular flange is fixed by the releasable fastener such that the bodies of elastomer material are subject to a predetermined axial precompression between the two flanges.

7. An assembly according to any one of claims 3 to 6, in which the intermediate annular body comprises a sheet metal disc whose radially inner part has alternating raised regions and depressed regions formed by means of plastic deformation of the disc and constituting two series of alternating hollow regions arranged on the opposing faces of the disc.

8. An assembly according to any one of claims 3 to 7, in which each body of elastomer material has one of its ends fixed to the base wall of the respective hollow region by vulcanization and has a plate fixed to its opposing end also by vulcanization, the plate being provided with a stud which is directed towards the facing surface of the adjacent flange, the adjacent flange having a plurality of holes into each one of which a corresponding stud projects.

9. An assembly according to any one of claims 3 to 8, in which the means for keeping the relative rotation between the intermediate body and the collar within predetermined limits consist of a plurality of stops each one of which is fixed to one face of the intermediate annular body and is arranged in a position which is in axial alignment with one of the bodies of elastomer material fixed on the other face of the disc, each of the-flanges which constitute the collar being provided with a plurality of slots, each one of which houses, with a predetermined amount of circumferential play, a corresponding one of the stops.

1 0. An assembly according to claim 1, substantially as described with reference to the accompanying drawings.