GB2165322A

GB2165322A - Clutch cover

Info

Publication number: GB2165322A
Application number: GB08523468A
Authority: GB
Inventors: Yoshinari Yoshimura; Nobutoshi Fujito
Original assignee: Exedy Corp; Daikin Manufacturing Co Ltd
Current assignee: Exedy Corp
Priority date: 1984-10-04
Filing date: 1985-09-23
Publication date: 1986-04-09
Also published as: GB2165322B; KR860003450A; JPS6188026A; GB8523468D0

Abstract

A clutch cover 1, of the type in which generally U-shaped projecting parts 5 having cross sections opening radially outwardly are formed at an inner peripheral portion of the clutch cover 1 in a circumferential direction with spaces provided therebetween, and a pair of wire rings 6 and a diaphragm spring 7 are held by the projecting parts 5, is provided with an annular reinforced part 11 which is formed integrally with the clutch cover 1 at a peripheral portion located further inwardly than the projecting parts 5. <IMAGE>

Description

SPECIFICATION Clutch cover This invention relates to a clutch cover of a type wherein wire rings and a diaphragm spring are held by a projecting part integral with the clutch cover in place of a stud pin.

The above mentioned type of clutch cover is generally called a DST (Diaphragm Spring Turnover) type, and has a plurality of tags (projections) 5 in place of or instead of the usual stud pins, as shown in Figs. 3 and 4.

The tags 5, generally u-shaped and having radial outward cross sections, are formed at an inner peripheral end portion of a clutch cover 1 in a circular direction with spaces provided therebetween, and a pair of wire rings 6 and a diaphragm spring 7 are held by circular faces of the tags 5.

In the conventional clutch cover construction as shown in Figs. 3 and 4, however, the rigidity of the clutch cover 1 is comparatively low. The clutch cover 1 bends when releasing a clutch, and therefore an initial loss of release operation length becomes large.

Futhermore, when the rigidity of clutch cover is low, lever sections 7a of the diaphragm spring 7 do not align on the same face and this causes mechanical noise at the time of clutch release operation.

An object of the invention is to solve the above disadvantages by improving the rigidity of clutch cover.

In order to accomplish the above object this invention provides a clutch cover of a type wherein generally U-shaped plural projecting parts having cross sections opening radially outwardly are formed at an inner peripheral end portion of the clutch cover in a circumferential direction with spaces provided therebetween, and a pair of wire rings and a diaphragm spring are held by the projecting parts, characterised in that an annular reinforced part is formed integrally with the clutch cover at an inner peripheral portion located further inwardly than the projectioning parts.

The invention will be described further, by way of example, with reference to the accompanying drawing in which: Figure 1 is a part-sectional oblique view of part of a preferred embodiment of the clutch cover of the invention; Figure 2 is a view in the direction of arrow 11 of Fig. 1; Figure 3 is a view comparable to that of Fig. 1 but of a conventional clutch cover; Figure 4 is a view in the direction of arrow IV of Fig. 3; and Figure 5 is a diagram comparing the release characteristics of the clutch of Figs. 1 and 2 against the clutch of Figs. 3 and 4.

The preferred clutch illustrated Figs. 1 and 2 comprises a clutch cover 1 fastened at its outer peripheral flange 1a to, for example, an engine flywheel 2 so that it rotates integrally with the flywheel 2. Inside the clutch cover 1 is a clutch disc 3 and a pressure plate 4 disposed in that order from the flywheel side.

On an inner peripheral end side portion of the clutch cover 1, a plurality of tags or projecting parts 5 are formed integrally with the cover 1 with spaces provided therebetween in a circumstantial direction. Each tag 5 projects toward the flywheel side and at the same time its cross section is formed into a generally Ushape opening radially outwardly. A pair of wire rings 6 are laid across radial outer peripheral side circular faces of the tags 5, and a diaphragm spring 7 is held between the wire rings 6. The diaphragm spring 7 engages by its oval shape hole 8 part with the tag 5.

A connecting part 10 extending to an inner peripheral side is further formed integrally with the clutch cover 1 in between the neighboring tags 5, and an annular reinforced part 11 is formed integrally with the cover 1 at an inner peripheral end portion of the connecting part 10. The annular reinforced part 11 is stepped shape in cross-section so as to have bent sections at an outer peripheral end and an inner peripheral end respectively.

An outer peripheral end portion of the diaphragm spring 7 contacts with a lateral projecting part 12 of the pressure plate 4. A radially separated lever section 7a is formed on an inner peripheral side portion of the diaphragm spring 7, and a release bearing 14 contacts with an inner peripheral end of the lever section 7a.

As can be seen more clearly in Fig. 2, the pressure plate 4 is connected at its outer peripheral end projecting part 4a to the clutch cover 1 by means of a strap plate 15, and rotates integrally with the clutch cover 1. Furthermore, the pressure plate 4 is urged in the direction of arrow R of Fig. 1 by means of a spring force of the strap plate 15.

Incidentally, in manufacturing the clutch cover 1, the tags 5 are formed by shearing and raising up a wall section of the clutch cover 1 toward the flywheel 2 side. Furthermore, a tip bent section 5a of the tag 5 is subjected to a bending work by a press machine after assembling the wire rings 6 and the diagragm spring 7 into the tags 5.

When the clutch is engaged, the outer peripheral end portion of the diaphragm spring 7 pushes the pressure plate 4 to the arrow F side against a spring force of the strap plate 15 and presses on a facing 3a of the clutch disc 3.

When the clutch is released by a clutch pedal etc., the release bearing 14 pushes an inner peripheral end portion of the diagragm spring lever section 7a to the arrow F side.

Thereby, the outer peripheral end portion of the diaphragm spring 7 moves toward an arrow R side. At this time the contacting portion of the wire ring 6 act as a supporting point. With the movement of the outer peripheral end portion of the diaphragm spring 7, the pressure plate 4 moves toward the arrow R side and leaves the facing 3a of the clutch 3 due to the spring force of the strap plate is, thus the clutch is disengaged.

The graph of Fig. 5 is comparison of the release characteristic curve of the preferred embodiment of the present invention as compared with a conventional embodiment. Curves X1, & X2, shown by solid lines, indicate release characteristics for the clutch provided with the annular reinforced part 11 according to the present invention, and curves Y1 & Y2, shown by dash lines, indicate release characteristics of the conventional embodiment. The curves X1 & Y1 indicate a relation between a stroke of the release bearing 14 and a movement of the pressure plate 4, and the curves X2 & Y2 indicate a relation between the stroke of the release bearing 14 and its release load.As seen from a comparison of the curves X1 and Y1, in the present invention an axial bending of the clutch cover 1 can be aboided owing to the annular reinforced part 11, so that a stroke S1 until the pressure plate 4 starts moving becomes shorter than a stroke S2 of the conventional embodiment.

Namely, an initial loss of stroke decreases when releasing the clutch to allow the clutch to be disengaged sharply.

Moreover, the reinforced part 11 serves also as a radiator fin to cool the clutch cover 1 during rotation of the clutch cover 1.

As explained above, in the clutch cover of the type wherein the generally U-shaped plural projecting parts having cross sections opening radially outwardly are formed at an inner peripheral end portion of the clutch cover in the circumferential direction with spaces provided therebetween, and the pair of wire rings and the diagragm spring are held by the circular face of the projecting part; the annular reinforced part is formed integrally with the clutch cover at the inner peripheral portion located inner than the projecting parts so that the following advantages become obtainable.

(1) Since the rigidity of the clutch cover 1 is improved by the annular reinforced part 11, the axial bending of the clutch cover 1 at the time of releasing can be decreased, and the initial loss of the stroke of the release bearing 14 decreases.

Thereby, a better clutch disengagement (responsibility) can be accomplished.

(2) Since the rigidity of the clutch 1 is improved, the axial bending of the clutch cover 1 at the time of releasing can be decreased, the lever sections 7a of the diaphragm spring 7 can be roughly aligned on the same plane even when releasing the clutch.

Thus, mechanical noise due to unevenness of the lever sections 7a can be reduced.

(3) Since the annular reinforced part 11 serves as the radiator fin of the clutch cover 1, a temperature rise of the clutch cover 1 due to friction of the pressure plate 4 can be avoided.

Claims

1. A clutch cover, in which generally Ushaped plural projecting parts having cross sections opening radially outwardly are formed at an inner peripheral end portion of the clutch cover in a circumferential direction with spaces provided therebetween, and a pair of wire rings and a diaphragm spring are held by the projecting parts, characterized in that an annular reinforced part is formed integrally with the clutch cover at an inner peripheral portion located further inwardly than the projecting parts.

2. A clutch cover as claimed in claim 1, in which a cross section of the annular reinforced part is stepped so as to have bent sections at an outer peripheral end and an inner peripheral end respectively.

3. A clutch cover as claimed in claim 1 or 2, in which a connecting part extending to an inner peripheral side is formed integrally with the clutch cover in between neighboring tags, and the annular reinforced part is formed integrally with the clutch cover through the connecting part.

4. A clutch cover as claimed in claim 3, in which the tags are formed by shearing and raising up a wall section of the clutch cover toward a flywheel side, and the remaining clutch section the of the clutch cover is utilized as the connecting part.

5. A clutch cover substantially as hereinbefore described with reference to and as illustrated in Figs. 1 and 2 of the accompanying drawings.