GB2030242A

GB2030242A - Friction lining

Info

Publication number: GB2030242A
Application number: GB7931512A
Authority: GB
Original assignee: Fichtel and Sachs AG
Current assignee: ZF Sachs AG
Priority date: 1978-09-15
Filing date: 1979-09-11
Publication date: 1980-04-02
Also published as: IT1193706B; IT7953563V0; DE7827426U1; FR2436290B1; NL7906799A; IT7968812A0; ES484195A1; FR2436290A1

Abstract

A friction lining 3, preferably for clutch discs of motor vehicle clutches, which is connected by rivets 5 with a lining carrier 2 and comprises a wear zone extending from the friction surface to the rivet head, and a remainder zone from the rivet head to the surface of support on the friction lining carrier. The friction lining 3 comprises lightening spaces 8, 10 in its remainder zone y. The two zones may be produced as separate layers joined by adhesive. Thus on the one hand the weight of the friction linings can be reduced, which especially involves a marked reduction of the inertia movement of a corresponding clutch disc, since the friction linings as is known are arranged in the radially outer region, and furthermore these lightening spaces can save friction material, which clearly reduces the purchase costs of a clutch disc. <IMAGE>

Description

SPECIFICATION Friction lining This invention relates to a friction lining, preferably for clutch discs of motor vehicle clutches, which is connected by rivets with a lining carrier and comprises a wear zone extending from the friction surface to the rivet head, and a remainder zone from the rivet head to the support surface on the friction lining carrier.

A friction lining of the above-stated construction type is known for example from German Publication Specification No. 1,750,376. In this case the lining carrier is made in two parts and resilient and a friction lining is connected with the lining carrier by rivets on each of the two outer sides. In this case the two friction linings are formed as closed rings and riveted on alternate sides, that is to say in alternation, with the one lining carrier and with the other lining carrier.

It is the problem of the present invention to produce a friction lining, preferably for clutch discs of motor vehicle clutches, which in comparison with the conventional friction linings possesses a lower weight, thus reduces the inertia moment of the clutch disc, and also has lower purchase costs.

This problem is solved in accordance with the invention in that the friction lining comprises lightening spaces in its remainder zone. This remainder zone of a friction lining, which remains after the wear zone is worn away, is advantageously provided with lightening spaces according to the invention.

Thus on the one hand the weight of the friction linings can be reduced, which especially involves a marked reduction of the inertia moment of a corresponding clutch disc, since the friction linings as is known are arranged in the radially outer region, and furthermore these lightening spaces can save friction material, which clearly reduces the purchase costs of a clutch disc.

It is further provided that the lightening spaces are made open in the direction towards the surface of support on the friction lining carrier. Such lightening spaces of open formation are especially simple to produce.

It is provided that support webs are formed out of the friction lining material between the individual lightening spaces. These support webs effect a uniform supporting of the friction lining on its lining carrier and prevent the material from sinking in at these points.

The invention provides that the lightening spaces are made approximately hemispherical. Lightening spaces of such formation combine a relatively high saving of weight and saving of material with an especially good force transmission between friction lining and lining carrier.

It is further proposed that the wear zone and the remainder zone be produced separately and connected for example by adhesion after production, and the lightening spaces be arranged in the remainderzone. By the separate production ofthewear zone and the remainder zone of a friction lining it is better possible to be able especially easily to influence the specific properties of each of these two zones. Moreover by way of example it is possible to produce the two zones from different materials.

It is quite especially advantageous that the lightening spaces in the remainder zone are formed in the form of piercings and the support webs have substantially constant material cross-section perpendicularly of the friction lining carrier. In this way it is possible to achieve a maximum of material saving and lightening of weight, without detriment to the supporting capacity. Thus the lightening spaces have approximately the same cross-section over the entire axial extent of the friction lining.

The invention will be explained in greater detail below with reference to the examples of embodimentwhich are illustrated in the accompanying drawings, wherein: Figure 1 shows the section through a clutch disc with friction lining according to the invention; Figure 2 shows the section through a lining carrier with a friction lining according to the invention fitted on one side; Figures 3 to 5 show various forms of embodiment of friction linings in accordance with the invention.

In the drawings, in Figure 1 the simplestform of a clutch disc for a motor vehicle clutch is reproduced.

In the present case it consists of a hub 1 which is displaceably arranged with a corresponding internal toothing on a gear shaft (not shown). The hub is firmly connected through an appropriate flange with a lining carrier 2 of disc form. This lining carrier 2 of disc form possesses a friction lining 3, made for example as a closed ring, on each of the two sides in its radially outer zone. The two friction linings 3 are firmly connected with the lining carrier 2 through rivets 5. Each friction lining 3 comprises in alternation a rivet hole 7 for the accommodation of a corresponding rivet head of a rivet 5 and a free hole 6.

This free hole 6 serves for the accommodation of the rivet head on the lining carrier 2 of an opposite friction lining 3. Admittedly it is also possible for each rivet 5 to connect both opposite friction linings 3 with the lining carrier 2. In both friction linings 3 there are formed lightening spaces 8 which will be explained in greater detail especially with reference to Figures 2 to 5.

Figure 2 shows the section through a friction lining 3 in enlarged representation, with the corresponding lining carrier 2. In the radially inner region a rivet hole 7 is arranged in which the head of a rivet 5 is situated, the other head of which is arranged on the side of the lining carrier 2 opposite to the friction lining. In the radially outer region a free hole 6 is arranged which serves for the introduction of that rivet which is to connect the opposite friction lining (not shown) likewise with the lining carrier 2. The wear zone of the friction lining 3, cooperating with the mating friction surface, has a heightx which in the new condition of the friction lining extends from its outermost limit down to the head of the rivet 5. A rivet lining can be worn away at maximum as far as an imaginary line parallel with this head.The remainder zone of the friction lining 3 with the extent y is worthless when the wear zone is worn away. The rivet hole bottom 12 in the friction lining 3 thus has a depth correspondingtothewearzonex plus the rivet head height. On the side facing the lining carrier 2 the friction lining 3 has lightening spaces 8 which have a maximum height corresponding to the remainder zone y of the friction lining. Between these lightening spaces 8 in each case support webs 11 are arranged. The lightening spaces 8 are made open to the surface 9 of support on the lining carrier 2. These lightening spaces serve to lighten the weight of the friction linings and thus to reduce the inertia moment of a complete clutch disc.Furthermore they serve to reduce costs in the production of the friction linings, this reduction of costs being effective especially due to the fact that the material of the friction linings is especially expensive.

In Figure 3 a friction lining 3 is illustrated which possesses lightening spaces 8 having a special form.

These lightening spaces 8 are made approximately cylindrical and have substantially the same crosssection over the entire remainder zone y. Thus the support webs 11 arranged between the individual lightening openings 8 are substantially of the same thickness. The remainder of the formation and the other references are in conformity with those of Figure 2.

Figure 4 shows a special configuration of the friction lining. This is divided into two zones 3 and 4 which are separate in production. The zone 3 of the friction lining has a heightx corresponding to the wear zone and the part 4 of the friction lining has a height corresponding to the remainder zone. In the zone 4 of the friction lining the lightening spaces 10 are formed extending through, that is to say they are arranged in the form of piercings. Practically con stant material cross-sections then resu It for the support webs 11 over the entire extent. The support surface 9 is provided for support on the lining carrier (not shown). The rivet hole bottom 12 as in the preceding figures is placed deeper by the head heighth of the rivet to be used than the wear zone x.Here again the rivet hole 7 for securing the friction lining to the lining carrier 2 is arranged radially inwards and the free hole 6 is provided radially outwards.

Figure 5 shows a modification of Figure 4. In this case the plane of separation between the zone 3 of the friction lining and the zone 4 of the friction lining is drawn down as far as the bottom 12 of the rivet hole 7. The zone 3 of the friction lining thus has a thickness z which corresponds to the sum of the two dimensionsx and h according to Figures 2 to 4. Thus while the height of the lightening spaces 10 is made less by the amounts, advantages in manufacturing technique result however since the rivet hole bottom 12 coincides with the plane of separation of the two friction lining parts. The other features of this friction lining correspond to those of Figure 4.

The formation of the lightening spaces can corres pond in plan view to all conceivable geometrical forms. It is advantageous to make these spaces round, rectangular or square. Irregular forms are also conceivable and by way of example it would be possible to go so far as to provide webs 11 in appropriate number only at the especially heavily stressed positions.

Claims

1. Afriction lining, preferablyforclutch discs of motor vehicle clutches, which is connected by rivets with a lining carrier and comprises a wear zone extending from the friction surface to the rivet head, and a remainder zone from the rivet head to the surface of support on the friction lining carrier, wherein the friction lining comprises lightening spaces in its remainder zone.

2. Afriction lining as claimed in claim 1,wherein the lightening spaces are made open in the direction towards the support surface.

3. Afriction lining as claimed in claim 1 or 2, wherein support webs are formed from the friction lining material between the individual lightening spaces.

4. A friction lining as claimed in claim 1,2 or 3, wherein the lightening spaces are made approximately hemispherical or cylindrical, possibly with rounded-out bottoms.

5. A friction lining as claimed in any one of claims 1 to 4, wherein the wear zone and the remainder zone are produced separately and connected for example by adhesion after production, and the lightening spaces are arranged in the remainder zone.

6. Afriction lining as claimed in claim 5, wherein the lightening spaces are formed in the remainder zone in the form of piercings and the support webs comprise substantially constant material crosssections perpendicular to the lining carrier or to the support surface.

7. A friction lining as claimed in claim 6, wherein the piercings extend substantially perpendicularly to the support surface.

8. Afriction lining substantially as described with reference to the accompanying drawings.