GB2273757A

GB2273757A - Clutch plate with double-row torsion damper

Info

Publication number: GB2273757A
Application number: GB9325143A
Authority: GB
Inventors: Alfred Schraut; Helmuth Weissenberger; Gunther Fuchsenberger
Original assignee: Fichtel and Sachs AG
Current assignee: ZF Friedrichshafen AG
Priority date: 1992-12-22
Filing date: 1993-12-08
Publication date: 1994-06-29
Anticipated expiration: 2013-12-08
Also published as: FR2699625A1; SE9304160L; DE4243545C2; BR9305183A; DE4243545A1; FR2699625B1; SE9304160D0; IT1266638B1; GB2273757B; SE509251C2; GB9325143D0; ITMI932308A0; ITMI932308A1

Description

2273757 CLUTCH PLATE WITH DOUBLE-ROW TORSION DAMPER The invention relates

to clutch plates for a f riction clutch. In particular, it relates to clutch plates for a friction clutch comprising a lining carrier with friction linings as an input component, a hub with internal splines as the output component, both arranged concentrically on an axis of rotation, two torsion spring devices acting in parallel between the two, coil springs which are arranged in each of the torsion spring devices on a common mean diameter in one plane and circumferentially distributed, control elements in the torsion device with windows for receiving and controlling the coil springs, which are made of substantially disc f orm and are connected on the one hand to the hub and on the other hand to the lining carrier.

A clutch plate with a double-row torsion damper is known for example from EP-PS -0 200 633. In this known clutch plate two completely separately constructed torsion dampers were connected to the lining carrier and the friction linings through a common carrier element and they were supported on the gear box shaft through a common intermediate hub. Such a construction is expensive in view of the multitude of individual components required (for example three splined hubs altogether), and furthermore the axial amount of space taken up is particularly high and the axial guiding of the two torsion dampers in relation to one another gives rise to problems.

Accordingly it is the aim of the present invention to improve significantly a clutch plate of the kind referred to above so that the drawbacks of the state of 2 the art are overcome and a simpler and more space-saving construction is obtained.

According to the invention this problem is solved by providing a clutch plate for a friction clutch comprising a lining carrier with friction linings as an input component, a hub with internal splines as the output component, both arranged concentrically on an axis of rotation, two torsion spring devices acting in parallel between the two, coil springs which are arranged in each of the torsion spring devices on a common mean diameter in one plane and circumferentially distributed, control elements in the torsion spring devices with windows for receiving and controlling the coil springs, which are made of substantially disc form and are connected on the one hand to the hub and on the other hand to the lining carrier, in which the coil springs of each spring device are controlled by respectively two disc-like control elements,_ which are arranged axially closely together in the region of planes perpendicular to the axis of rotation and each being rigidly secured respectively, one to the lining carrier and one to the hub.

By controlling each of the two torsion spring devices by respectively only two disc-shaped control elements it is possible, as compared with the state of the art, to save at least two disc-shaped components, whereby the outlay on manufacture is reduced and the space taken up axially can be cut down.

According to a further feature of the invention it is of advantage to allow the respective conc.entric toruses formed by the end faces of the helical springs of the torsion spring devices to extend immediately next to one another without any significant 3 spacing. In this way a particularly compact construction in the axial direction can be obtained as the two sets of helical springs can be arranged in a row directly axially adjacent.

As a further important feature with regard to saving space axially it is proposed that one of the two toruses should have a smaller mean diameter than the other and accordingly the two planes have a smaller axial spacing than the sum of the radii of the two toruses. In this way the axial space taken up can be further significantly reduced.

According to a further feature of the invention the individual helical springs of the one torsion spring device are arranged circumferentially staggered or offset in relation to the individual helical springs of the other torsion spring device. In this way it is possible to achieve a favourable construction of the individual control elements and - their associated control edges from the strength point of view.

It is furthermore proposed that the two axially innermost control elements should be rigidly secured to the lining carrier and the two outermost ones to the hub. In this way automatically an axial securing of the two innermost control elements is achieved in that they can abut directly on the outer ones without additional components being needed.

In this construction both the outer control elements have bulges in the neighbourhood of the helical springs f or guiding the springs. In this way the individual helical springs are secured at least in an outward direction.

4 The two inner control elements are, according to the invention, combined into one structural unit in the f orm of a cage. The individual parts of this cage can accordingly easily be manufactured according to requirements and the resulting structural unit is not only easy to handle - e.g. during assembly - but it is also particularly stable in shape with regard to the transmission of large torques.

According to a further feature of the - invention the one control element is made of substantially disc-like shape and accordingly is easy to produce and at the same time it is extended radially outwards to receive the friction linings and the other is provided substantially with axially extending regions which serve to bridge the axial spacing between the two planes perpendicular to the axis of rotation [E 1 and E 21.

In this connection the other control element is made from a concentrically enclosing ring which is of conical f orm and in f act widens out f rom the plane E 2 to the plane E 1 - corresponding to the difference in the diameters [D 1 to D 2] of the two torsion spring devices, this ring locating the torsion springs of the torus D 1 in an axial direction.

In addition flaps extend outwards from the ring parallel to the plain E 2' these rings extending radially inwards tightly adjacent to the corresponding outer control element and being provided with peripheral control edges for the helical springs. These flaps extend radially inwards parallel to the associated outer control element and are accordingly easy to produce.

The f laps are furthermore bent back in their end regions axially towards the substantially likewise f lat control element and are arranged with noses in corresponding openings in this control element for mutual location and attachment. To enhance the cage thus formed the noses could be welded into the corresponding openings.

In this arrangement the bent back regions of the flaps form in a particularly advantageous manner a central locating diameter which is located on an outside diameter of the hub. In this way the cage is accurately located on an outside diameter of the hub as a whole in a radial direction using components which are already present.

In this arrangement the flaps extend approximately in the circumferential regions of the helical springs of the opposing torsion spring device, i.e. , they extend into the gaps of the individual helical springs which they are designed to control.

At points circumferentially offset from these flaps there are further flaps formed out of the ring, extending inwards and in fact axially spaced from the plane E 2 for axially guiding the helical springs which are controlled by the other flaps. In this way the cage made up of the two components not only serves to control the two sets of helical springs but also guides them in an axial direction.

Further noses are formed from the ring in the region of its outer periphery and extending in a direction towards the other control element in such a way that they extend circumferentially offset in relation to the torsion springs of this torsion spring 6 device and engage without play in openings in the control element at least circumferentially for locating and securing both parts together. By virtue of this support a further enhancement of the strength of the cage is achieved, the mutual attachment preferably being formed by a welded seam.

Furthermore the control element has in its radially inner region radially within the window for controlling the helical springs of the larger mean diameter - a region which is axially extended in the direction towards the ring for receiving a friction device. The arrangement of the friction device, of advantage for damping the torsional vibrations, in this region is particularly advantageous as it involves so to speak the helical springs of the torsion spring device of larger mean diameter and this space can be well utilised in this way.

The invention is further explained in the following in conjunction with an embodiment by way of example. In the drawings:

Fig. 1 is a partial view of a clutch plate; Fig. 2 shows the upper half of a section on II-II in Fig. 1; Fig. 3 shows the upper half of a further section III-III in Fig.1; Fig. 4 shows a partial view "B" in Fig.2.

Fig.1 shows a partial view of a clutch plate 1 having a hub 4 and a sheet metal cover plate 12 on which the friction linings 5 are secured radially outwards, as well as helical springs 8 and 9 which each belong to a complete set and are arranged axially offset and also at different diameters. All the 7 components are concentric with the axis of rotation 2 and can rotate about it.

The inner construction of the clutch plate 1 is best further seen in conjunction with Figures 2 to 4.

Figures 2 and 3 show respectively sections II-II and III-III in Fig.l. In this connection Fig.1 represents the view "A" in Figs.2 and 3. The clutch plate 1 comprises on the one hand friction linings 5 on a lining carrier 3 which is to be regarded as the input component of the clutch plate 1. on the other hand the hub 4 is known as the output component to the extent that it is arranged in a rotationally secure manner, through internal splines, on a gearbox shaft, not shown, concentric with the axis of rotation 2.

Arranged between the lining carrier 3 and the hub 4 is a torsional vibration damper comprising two torsion spring devices 6 and 7 which are connected in parallel and accordingly operate simultaneously. In this connection the helical springs 8 of the torsion spring device 6 form with their end faces a first torus T 1 having a mean diameter D 1 and the helical springs 9 - see in particular Fig.3 - form a torus T 2 having a mean diameter D 2 Both torsion spring devices 6 and 7 are arranged with their toruses T 1 and T 2 in the planes E 1 and E 2 perpendicular to the axis 2. The torsion springs 8 and 9 in this arrangement are arranged circumferentially offset in relation to one another, as can be seem in particular in Fig.l. To achieve a particularly space-saving layout in the axial direction the diameters D 1 and D 2 are made dif f erent so that the two planes E 1 and E 2 can have a smaller mutual axial spacing than the sum of the radii R 1 + R 2 corresponding to the diameters of the springs 8 and 9. All the torsion springs 8 and 9 of the two torsion spring devices 6 8 and 7 are controlled directly by control elements 10 and 11 on the one hand as well as by the cover pressings 12 and 13 on the other hand. In this layout the control regions of the components 10 to 13 in the range of extent of the torsion springs 8 and 9 are arranged to extend substantially radially, and in fact respectively close to the two sides of the two planes E 1 and E 2 In this way it is possible to act on the springs 8,9 with torque with respectively only two control elements in the region of the planes E 1 and E 2 The two pressings 12 and 13 are secured directly to the hub 4 by rivets 34 and - held at a corresponding axial spacing - form the axial limits of movement for the torsion spring devices 6 and 7 and thereby also for the lining carrier 3 carrying the friction linings 5. For this purpose the pressings 12 and 13 have bulges 14 and 15 which are provided in the region of the individual helical springs 8 and 9 in order to locate the latter in an outward direction. On the other hand the inner control elements 10 and 11 are located in both axial directions by appropriate shaping, in that circumferentially outside the spaces occupied by the springs 8 and 9 opposed engaging faces are provided opposite the pressings 12 and 13 in the region of the planes E 1 and E 2 The components 10 and 11 which are secured against rotation to the lining carrier 3 are combined and secured together to form a cage 33. In this arrangement the control element 11 comprises a ring 16 extending concentric to the axis 2 and of cone-like cross-section and it widens out from the plane E 2 in the direction towards the plane E 1 Its inner prof ile is of such a f orm that it axially secures the coil springs 8 of the torsion spring device 6 in opposition to the bulges 14. Flaps 17 extending radially inwards from the ring 16 are arranged in one piece, which extend radially inwards 9 and in fact parallel to the plane E 2 and close to it. These flaps 17 form an axial location for the cage 33 in the direction of the torsion spring device 7 and in fact opposite the pressing 13. Furthermore the flaps 17 have in a circumferential direction control edges 18 which control the coil springs 9. In their radially inner region the flaps 17 are extended axially in the direction towards the control element 10 through bent-back regions 22, these bent-back regions 22 terminating in noses 20 which project into corresponding openings 19 in the region of the radial inside diameter of the control element 10, in order to produce a connection preventing relative rotation. In this arrangement the noses 20 are advantageously securely connected to the control element 10 in the region of the openings 9 by a seam weld 21 (see in particular Fig.4). The bent-back regions 22 of the flaps 17, which are arranged distributed circumferentially, define a locating diameter 24 which is seated on a corresponding outside diameter 23 of the hub 4 - for radially locating the cage 33 and the friction linings 5. Further flaps 28 are formed projecting radially inwards from the ring 16 and are arranged circumferentially offset - with respect to the flaps 17 - and locate the coil springs 9 of the torsion spring device 7 in a direction towards the torsion spring device 6. They project into the torus T 1 at the points at which none of the coil springs 8 are present. Moreover noses 29 are formed from the ring 16 in the region of its greatest diameter and project into corresponding openings 30 in the control element 10 in a manner which, at least circumferentially, is without any play, and there they are preferably secured by a seam weld 31. These noses 29 are arranged at the same radial region as the flaps 28 and the openings 30 in the control element 10 - see Fig.4 - in a circumferential region outside the window 25 for the coil springs 9. As is evident particularly in Figs 2 and 3, the coil springs 8 of the torsion spring device 6 are arranged in windows 27 of the pressing 12 and in windows 25 of the control element 10 and the coil springs 9 in windows 26 of the pressing 13 and they are controlled by the control edges 18 of the flaps 17 on the ring 16. Control element 10 and lining carrier 3 could be made as a single component, but it is advantageous to make the two components separate and weld them together, e.g. by means of a circumferential seam weld. This allows the material thickness to be better matched to its function. The friction device 32 present for torsional damping is arranged in the radially inner region of the control element 10, and in fact radially within the torus T 1 which has a greater mean diameter D 1 than the torus T 2 In this region the control element 10 is axially extended in the direction towards the torsion spring device 7 so that there arises in the resulting gap in relation to the pressing 12 a space in which the friction device 32 can be mounted. In the usual way it can comprise at least one abutment ring and one spring.

The clutch plate described in Figs 1 to 4 has a very compact construction and by the construction of the cage 33 it is a very rigid form. In this connection the individual helical springs 8 and 9 can naturally also come into action in stages one after the other. In this way a progressive spring characteristic can be obtained. The space taken up by the two torsion spring devices 6 and 7 is kept within limits in that the two toruses T 1 and T 2 formed by the coil springs 8 and 9 are of different diameters and are packed closely together in an axially direction. The torus T 1 formed by the larger mean diameter D 1 11 allows the mounting of the friction device in its radial inner region.

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Claims

1 A clutch plate for a friction clutch comprising a lining carrier with friction linings as an input component, a hub with internal splines as the output component, both arranged concentrically on an axis of rotation, two torsion' spring devices acting in parallel between the two, coil springs which are arranged in each of the torsion spring devices on a common mean diameter in one plane and circumferentially distributed, control elements in the torsion spring devices with windows for receiving and controlling the coil springs, which are made of substantially disc form and are connected on the one hand to the hub and on the other hand to the lining carrier, in which the coil springs of each torsion spring device are controlled by respectively two disc-like control elements, which are arranged axially closely together in the region of first and second planes perpendicular to the axis of rotation and each being rigidly secured, one to the lining carrier and one to the hub.

2. A clutch plate according to claim 1, in which concentric toruses formed respectively by the end faces of the coil springs of the torsion spring devices extend directly adjacent to one another without any significant spacing.

3. A clutch plate according to claim 2, in which one of two toruses has a smaller mean diameter than the other and accordingly the two planes perpendicular to the axis of rotation have a smaller mutual spacing than the sum of the radii of the two toruses.

4. A clutch plate according to claim 3, in which the individual coil springs of the one torsion spring 13 device are arranged circumferentially offset in relation to the individual coil springs of the other torsion spring device.

5. A clutch plate according to claim 4, in which the two axially innermost control elements are rigidly secured to the lining carrier and the two outer ones to the hub.

6. A clutch plate according to claim 5, in which both outer control elements have bulges in the region of the coil springs for locating the springs in an outward direction.

7. A clutch plate according to claim 5, in which both inner control elements are combined together to form a structural unit in the form of a cage.

8. A clutch plate according to claim 7, in which one, preferably that associated with the coil springs of the larger diameter torus, control element is of substantially disc shape and is made directly radially outwardly extended, for receiving the friction linings, and the other control element is provided with substantially axially extending regions for bridging across the axial spacing between the two planes perpendicular to the axis of rotation.

9. A clutch plate according to claim 8, in which the other control element comprises a concentrically extending ring which is made conical in cross-section and in fact diverging outwards from the second plane perpendicular to the axis of rotation to the other, extending substantially tangentially and at a small spacing from the larger diameter torus and axially locating the coil springs of the torsion spring device.

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10. A clutch plate according to claim 9, in which f laps extend from the ring parallel to the second plane perpendicular to the axis of rotation, these flaps extending radially inwards directly adjacent the corresponding outer control element and being provided with peripheral control edges for the coil springs of the torsion spring device.

11. A clutch plate according to claim 10, in which the flaps are bent back axially towards the control element in their end regions and are arranged with noses in corresponding openings of the latter for mutual location and attachment.

12. A clutch plate according to claim 11, in which the bent-back regions of the flaps define a central locating diameter which is located on an outs-ide diameter of the hub.

13. A clutch plate according to claim 12, in which the flaps extend approximately in the circumferential region of the coil springs of the torsion spring device.

14. A clutch plate according to claim 10, in which further flaps are formed from the ring, circumferentially offset from the flaps, extending inwards and in fact axially spaced from the second plane perpendicular to the axis of rotation for axially guiding the coil springs of the torsion spring device.

15. A clutch plate according the claim 14, in which noses are formed in the direction towards the control element from the ring in the region of its outer periphery so that they extend peripherally offset in relation to the torsion springs of the torsion spring device and engage in openings of the control element in a manner which is free from play at least circumferentially, for locating and securing the two components together.

16. A clutch plate according to claim 15, in which the control element having the larger mean diameter of its torus has in its radially inner region, radially within the window for controlling the coil springs, axially in the direction towards the ring an offset portion for receiving a friction device comprising at least one abutment ring and one spring.

17. A clutch plate substantially as described herein with reference to and as illustrated in the accompanying drawings.