GB2075618A

GB2075618A - Pulled diaphragm spring clutch

Info

Publication number: GB2075618A
Application number: GB8114154A
Authority: GB
Original assignee: Fichtel and Sachs AG
Current assignee: ZF Friedrichshafen AG
Priority date: 1980-05-08
Filing date: 1981-05-08
Publication date: 1981-11-18
Also published as: GB2075618B; DE3017563C2; FR2482225A1; JPH0152609B2; FR2482225B1; JPS571827A; DE3017563A1; BR8102827A

Abstract

In the region of the radially outer edge of a friction disc a diaphragm spring (11) is arranged on the side of a first clutch part (5) remote from a second clutch part (1). The diaphragm spring (11) bears with intermediate region (15) on the first clutch part (5) and releases the first clutch part and the friction disc on traction loading of tongues (17) extending to the inner edge. From the outer edge of the diaphragm spring (11) tongues (21) protrude, which are secured directly to the second clutch part (1). Between the tongues (21) recesses (23) are provided so that the diaphragm spring (11) can be deformed elastically over an adequate distance despite rigid securing. In a second embodiment (Figs. 5 and 6 (not shown)) the tongues (21) are cupped to extend axially towards the second clutch part (1) and in a third embodiment (Fig. 7 (not shown)) the recesses have an arcuate form. The invention is said to achieve a clutch having no need for the usual cover or housing. <IMAGE>

Description

SPECIFICATION Pulled diaphragm spring clutch The invention relates to a membrane spring clutch with two clutch parts rotatable about a common axis of rotation, of which the first clutch part is held axially movably on the second clutch part, an axially movably ar ranged friction disc arranged between the clutch parts, and a membrane spring on the side of the second clutch part remote from the first clutch part, which spring is held on the second clutch part in the region of its radially outer periphery, on its inner periphery is pro vided with operating members for an axial movement away from the clutch parts, and in the region of the middle diameter between the inner and outer peripheries is spring-loaded on the first clutch part.

A pulled diaphragm spring clutch of this type of construction is known for example from German published specification 2121920.

The two clutch parts, which are relatively non-rotatable, are formed by the flywheel and the usual presser plate. The flywheel is mounted on the drive shaft of the engine while the friction plate is attached to the gearbox. The membrane spring is mounted in a special housing which engages behind the side of the membrane spring remote from the clutch parts. The special housing increases the construction requirement and the mounting requirement of the known clutch.

The object of the present invention is to provide a way which constructionally simpli fies the pulled spring clutch of the known type and thereby reduces manufacturing costs.

This object is achieved according to the present invention in that the membrane spring in the region of its outer periphery is directly fixed to the second clutch part. In this manner the additional housing of the known pulled clutches can be omitted.

The fixing of the membrane spring to the second clutch part must be effected in a flexible manner so that during operation of the clutch the membrane spring may deform. This can be most easily achieved in that the mem brane springs along their outer peripheries are provided with fixing members spaced apart from each other and rigidly fixing the outer periphery to the second clutch and are pro vided with recesses between the fixing points.

The recesses form between them individuai tongues formed on the membrane spring. The free ends of said springs can be screwed or riveted to the second clutch part; that is to the flywheel. The flexibility of the membrane spring is thereby not impaired. Especially not if the tongues in the circumferential direction of the membrane spring are smaller than the opposite spacing and/or if the spacing of the fixing positions in the circumferential direction is approximately equal to half the diameter of a circle through the fixing positions.

The recesses can be formed as cutouts with closed periphery but can also be open to the membrane spring at their outer periphery.

Because the second clutch part is potshaped the membrane spring including the tongues can run substantially flat. Alternatively, the membrane spring can be formed pot-shaped in a clutch having a substantially planar flywheel.

The invention will next be explained in greater detail by reference to the forms of embodiment illustrated in the drawings, wherein in detail: Figure 1 is a front elevation of a first embodiment of a pulled membrane spring clutch, Figure 2 is a cross section taken along the line ll-ll of Fig. 1, Figure 3 is a partial view of the membrane spring clutch according to Fig. 1 in the direction of arrow Ill, Figure 4 is a front elevation of another embodiment of a membrane spring clutch, Figure 5 is a cross section along the line V-V of Fig. 4, Figure 6 is a partial view of the membrane spring clutch according to Fig. 4 in the direction of arrow VI, and Figure 7 shows another embodiment of a membrane spring which can be used in the membrane spring clutch of Fig. 1.

The pulled diaphragm spring clutch according to Figs. 1 to 3 comprises a pot-shaped flywheel 1 which encloses the clutch disc 3 and the presser plate 5. The presser plate 5 is here connected fast in rotation but axially displaceably with the flywheel 1 through tangential straps 7. In the present case the tangential straps 7 are for the one part screwed directly to the flywheel 1 and for the other fastened through noses 9 to the presser plate 5. However it is readily possible to screw the tangential straps 7 fast to the common component 11, instead of to the flywheel 3.In the present case this common component 11 is of disc form and made approximately flat, is secured at its outer circumference through screws 1 3 firmly with the flywheel 1, lies under initial stress with its middle diameter 1 5 on the presser plate 5, and is provided radially inwards with spring tongues 1 7. These spring tongues 1 7 are formed by corresponding radial slots 1 9. The common component 11 unites in itself both the housing and the diaphragm spring. It has securing parts 21 for the passage of the screws 13, while recesses 23 are provided between the individual securing parts 21. The fixing tongues 21 form flexible linking bands which despite their firm fixing on the flywheel 1 allow a deformation of the membrane spring 11.Furthermore the starter gear wheel 24 is arranged externally on the flywheel 1.

Alternatively it is of course possible to fix the tangential straps to the membrane spring 11 instead of the flywheel 1.

The function of this pulled clutch is as follows: In the coupled condition the clutch disc 3 is clamped in between the presser plate 5 and the flywheel 1 by the initial stress of the common component 11. Thus the force transmission takes place from the internal combustion engine (not shown) by way of the flywheel 1 and the presser plate 5, the clutch disc 3 and the drive-output shaft (likewise not shown). To release the clutch the spring tongues 1 7 are drawn by a disengager mechanism (not shown) away from the clutch, so that the common component 11 is conically deformed and its middle diameter 15, together with the presser plate 5, carries out a release movement by moving axially. Thus the clutch disc 3 is guided loosely between presser plate 5 and flywheel 1.

In Figs. 4 to 6 a variant of embodiment according to Figs. 1 to 3 is illustrated. In this case the flywheel 25 is of flat formation, but on the other hand the common component 27 is of pot form. Thus the latter embraces the presser plate 29 and the clutch disc 31. At the fastening parts 33 it is screwed by screws 35 to the flywheel 25. Considered in the circumferential direction, between these fastening parts 33 in each case a recess 37 is formed which extends substantially over the whole axial extent of the common component 27. The other components of this pulled clutch correspond to those of Figs. 1 to 3.

The function is also the same. In the present case the presser plate 29 is connected fast in rotation through the known tangential strips 39 directly with lugs 41 on the common component 27. It is however readily possible to secure the tangential strips 39 directly on the flywheel 25.

Fig. 7 shows a common component 43 which, in contrast to.those in Figs. 1 to 3, comprises recesses 47, which are made arcuate with centre point arranged externally, between the fastening parts 45 lying one behind the other in the circumference. The radius of these recesses 47 is here preferably made in an order of magnitude which corresponds to half the external diameter of the common component 43. Moreover from Fig. 7 there may be seen the middle diameter 49, the radial slots 51 and the spring tongues 53.

The form of the recesses 47 according to Fig.

7 can naturally readily be transferred to the pot-shaped common component 27 according to Figs. 4 to 6.

Claims

1. A diaphragm spring clutch having two clutch parts (1, 5; 25, 29) rotatable about a common axis of rotation, of which the first clutch part (5; 29) is held axially displaceably on the second clutch part (1; 25), a friction disc (31) arranged axially displaceably between the clutch parts (1, 5; 25, 29), and having a diaphragm spring (11; 27; 43) arranged on the side of the first clutch part (5; 29) axially remote from the second clutch part (1; 25), which spring is held in the region of its radially outer edge on the second clutch part (1; 25), is provided on its inner edge with actuating elements (17, 53) for a movement pulling axially away from the clutch parts (1, 5; 25, 29) and is supported in the region of a diameter between the inner and the outer edges under resilient initial stress'on the first clutch part (5; 29), said diaphragm spring (11, 27, 43) being secured in the region of its outer edge directly on the second clutch part (1; 25).

2. A diaphragm spring clutch as claimed in claim 1, wherein the diaphragm spring (11; 27; 43) is secured along its outer edge rigidly at a plurality of fastening points arranged with spacing from one another to the second clutch part (1; 25) and comprises recesses (23; 37; 47) extending through between the fastening points.

3. A diaphragm spring clutch as claimed in claim 2, wherein the fastening points are placed radially outside the radially innermost edges of the recesses (23; 37; 47).

4. A diaphragm spring clutch as claimed in claim 2, wherein the recesses (23; 37; 47) are open towards the outer edge of the diaphragm spring (11; 27; 43) and the fastening points are provided on tongues (21; 33).

5. A diaphragm spring clutch as claimed in claim 4, wherein the tongues (21) protrude radially.

6. A diaphragm spring clutch as claimed in claim 4, wherein the tongues (33) protrude axially from the outer edge of the diaphragm spring (27) and are secured at an axial distance from the outer edge to the second clutch part (25).

7. A diaphragm spring clutch as claimed in claim 4, wherein the tongues (21, 33) are narrower in the circumferential direction ofthe diaphragm spring (11, 27) than their mutual spacing.

8. A diaphragm spring clutch as claimed in claim 7, wherein the spacing of the fastening points in the circumferential direction is approximately equal to half the diameter of a circle through the fastening points.

9. A diaphragm spring clutch as claimed in claim 4, wherein the recesses (47) have a substantially concave arcuate form.

10. A diaphragm spring clutch as claimed in claim 9, wherein the radius of the recesses (47) is approximately equal to half the diameter of a circle through the fastening points.

11. A diaphragm spring clutch as claimed in claim 2, wherein the diaphragm spring (11, 27, 43) is screwed by means of screws (13, 35) to the second clutch part (1; 25).

1 2. A diaphragm spring clutch as claimed in claim 1, wherein the second cluch part (1) carries a flange readhing radially outwardly axially past the friction disc (3) and the first clutch part (5) and the diaphragm spring (11) being substantially flat and secured in the region of its outer edge to the axially facing face of the flange.

1 3. A diaphragm spring clutch as claimed in claim 1, wherein the diaphragm spring (27) is made as a part shaped by bending which at its radially outer edge reaches at least in zones radially outwardly axially-past the first clutch part (29) and the friction disc (31) and is secured to the second clutch part (25), and wherein the recesses (37) extending substantially over the whole axial length of the axially proceeding zones of the diaphragm spring (27).

14. A diaphragm spring clutch as claimed in claim 13, wherein the side of the second clutch part (25) axially facing the diaphragm spring (27) is substantially flat.

1 5. A diaphragm spring clutch substantially as described herein with reference to the accompanying drawings.