FR2694795A1 - Clutch disc with spring for lining. - Google Patents

Abstract

In this disc, the bearing zone (11, 12) of each lining spring (6) is disposed radially outside its flat bearing zone (10), reaches the other friction lining ring (5), by means of a connecting zone (11) extending obliquely with respect to the axis of rotation, and has an end zone (12), projecting substantially radially, on which the further friction lining ring (5), and in that the lining springs (6) are individually arranged one behind the other in the peripheral direction, with their alternating curvatures.

Description

i Clutch disc with spring for lining The invention relates to a

  clutch disc intended to be mounted in a friction clutch for a motor vehicle with a hub for rotationally fixed mounting on a gearbox shaft, a disc part arranged concentrically with respect to the hub, which has in the area of its outer periphery at least one spring for gasket with elasticity oriented in the axial direction, as well as two rings of friction gasket, fixed back-to-back on the gasket spring, with interposition of the latter, and the gasket spring having, in the radial direction, a flat area for the support of the friction lining rings, as well as at least one area provided with a curvature or inflection, connecting to the flat area, which corresponds substantially to the radially outer area, respectively radially inner, rings of

friction lining.

  Clutch discs of the aforementioned type are known for example from US-PS-2 309 950 In this clutch disc, however, pairs have been constructed, formed of two lining springs, and both having both a flat area , for the support of the friction lining rings, that also each time a curved zone, the first lining spring having its curved zone oriented radially towards the outside and the other oriented radially towards the inside By the DE- OS 2920 095, a clutch disc is known in which also the lining springs are arranged in pairs, having both a curved region radially outward and also radially inward. The curved zones serve in both cases to create an axial elasticity between the two rings of friction lining, this axial elasticity contributing essentially to the comfort at start-up and to the regularity of the contact, by friction, of the rings of

friction lining.

  The object of the present invention is to provide an elastic packing assembly, for friction packing rings, having in the region radially

  greater elastic rigidity than in the radially inner zone and with which it is possible to obtain a torque as low as possible.

  To this end, the clutch disc according to the invention, of the type comprising: a hub (2), centered relative to the axis of rotation (4), for mounting on a gearbox shaft, a part disc (3), concentric with the hub (2), an arrangement of springs for a gasket, with an axially oriented elastic effect, connected to the disc part (3), in the region of the outer periphery of the latter, two friction lining rings (5), arranged axially back-to-back, on both sides of the packing spring arrangement, fixed to the packing spring arrangement, the packing spring arrangement having several springs for gasket (6) distributed in the peripheral direction, each of which has with respect to the axis of rotation (4) a flat bearing area (10), located radially outside a foot area (13) connected to the disc part (3), intended to carry and fix one of the two rings of friction lining (5), and has a support zone (11, 12), folded in the direction of the other of the two rings of friction lining (5), is characterized in that the zone of support (11, 12) of each lining spring (6) is arranged radially outside its flat bearing region (10), reaches the other friction lining ring (5), by the intermediate a connection zone (11) extending obliquely to the axis of rotation, and has an end zone (12), projecting substantially radially, on which the other ring of friction lining rests (5), and in that the packing springs (6) are arranged individually one behind the other in a peripheral direction, with their

alternating curvatures.

  By means of the configuration according to the invention, it is possible to avoid double-sided friction linings, so that in this way the moment of inertia can be considerably reduced, since, precisely in the area Radially outer, a significant saving in weight can be made. On the other hand, the configuration of the packing spring used is such that the connection zone located radially on the outside offers a significantly greater elastic stroke than that which is located radially at inside, so

  that the elastic resistance increases with the diameter.

  Thanks to this arrangement, it is obtained that, during the starting process, the mean effective friction radius is displaced in the radially outer zone of the friction lining rings, so that the transmission torque that can be transmitted effectively for a category of diameter determined clutch disc is maximum In doing so, a clutch equipped with such a clutch disc tends to slip less and

  lining wear during the clutch process.

  Advantageously, the flat bearing zone (10) of each lining spring (6) is connected to the foot zone (13), by means of an additional connection zone (14), located radially inside. and extending obliquely to the axis of rotation, and in that the connection region (11) radially outside is longer in the axial direction than the connection region (14) extending radially to the inside. According to another characteristic of the invention, the gasket spring is arranged, in the relaxed state, in its foot region midway between the friction lining rings, and is connected to the flat zone by means of of obliquely extending connecting zones In the region radially on the inside, this also provides a homogeneity of the distribution of the elastic force, for the bends, oriented in both directions, of the spring for

garnish.

  It is proposed to connect the springs for the lining to form a single ring, in which the separation of the two alternating individual curvatures is effected by means of slots extending substantially radially, traveling radially internally up to the foot area On achieves very simple handling during assembly, using a single spring to

  trim, making the entire circumference.

  However, it is also possible, without problem, to provide pairs of springs for packing distributed on the periphery, which are distributed by two at the periphery, by means of a slot extending radially, the slot running radially inwards up to to reach the foot area, and the parts which go around the periphery, from the slit, being provided with curvatures oriented in opposite directions These springs for linings can be produced with very little fall during the blurring and can be assembled entirely as precisely as other packing springs

individual.

  It may however also be advantageous, without posing any problem, to use springs for individual linings, distributed around the periphery, alternately provided with a curvature oriented axially in both directions. In this type of lining spring, the greatest peripheral division is made so as to constitute springs for individual linings, this construction giving very great insensitivity to the delay obtained in the event of

temperature spikes.

  In addition, the flat bearing area (10) of each lining spring (6) is connected to the foot area (13), via an additional connecting area (14), extending radially to inside and obliquely with respect to the axis of rotation, and in that the radially outer connection zone (11) is of dimension allowing greater elastic resistance

  as the radially inner connection zone (14).

  Advantageously, each friction lining ring is fixed approximately halfway between its radial extent, by means of a lining rivet, on a corresponding curvature, in a flat area of the lining spring. way very few rivets to achieve a low moment of inertia, everything

by having a perfect fixation.

  The invention is explained in more detail below with the aid of an exemplary embodiment. In the drawing: FIG. 1 represents the upper half of a longitudinal section of a clutch disc, observed along a line II of FIG. 2, and FIG. 2 represents a packing spring according to the

figure 1.

  The clutch disc 1 according to FIG. 1 has a basic structure comprising a hub 2, subjected in rotation to a gearbox shaft, not shown. On the hub 2 is fixed, by rivets 9, a disc part 3 bearing springs for its outer diameter 6 A torsional vibration damper can be arranged in the area of

the disc part 3.

  In the drawing, several packing springs 6 are provided which, mounted on the periphery of the disc part 3, by means of fixing rivets 8, packing springs 6, are shown in elevation in FIG. 2 The packing springs 6 are produced, in pairs, in the form of individual pieces and are fixed by being distributed at the periphery on the disc part 3 Each pair of these springs for packing 6 has, at the periphery, two zones separated from each other at by means of a radially extending slot 15 This slot 15 extends radially from the outside, to a common foot area 13 Each part of the packing spring, which is connected in a peripheral direction to the slot 15, is of a different curvature, in particular, according to FIG. 1, a curved zone in the direction of a friction lining ring 5 and the other zone is curved in the direction of the other friction lining ring 5 Each of these zones s has a flat area 10, serving as a bearing surface, with a large area, for the corresponding friction lining ring 5 Simultaneously, is provided inside the flat area 10, on an average diameter, the fixing facing the friction lining rings 5, which is in the form of a lining rivet 7 Between the flat zones 10 of the lining springs 6 and the foot zone 13 are provided internal connection zones 14, extending obliquely by

  relative to a radial plane passing through the axis of rotation 4.

  By means of an identical configuration of the two zones of each lining spring 6, a symmetrical arrangement is obtained between the flat zones 10 and the foot zone 13. Thus, in the relaxed state, the foot zone 13 is distant at equal distance from the two friction lining rings 5 Radially outside the flat area are also arranged connecting areas 11 extending obliquely, going from the inner wall, that is to say from the back of a first friction lining ring 5, up to the interior wall of the other friction lining ring 5 and bearing on the face, opposite the flat area 10, of an end area 12 connecting to the area link 11, which also presses, with a large area, on the ring of

friction lining 5.

  Thanks to the arrangement of the packing springs according to FIGS. 1 and 2, it is ensured that the elastic resistance of the set of packing springs 6 in the axial direction increases by going radially from the inside towards the outside, this on the radial extent of the friction lining rings 5 This can be influenced by the configuration of the connection zones 14, by being able to modify their radial extent, that is to say the value of their axial projection In addition, we obtain, thanks to this configuration of the lining springs 6, a reduction in the inertia of the clutch disc due to the fact that when observing at the periphery it is each time provided in the area of each lining spring

  only one of these packing springs.

  According to a variant to the springs for lining shown in FIGS. 1 and 2, it is also however possible to connect the springs for lining, to form a single ring of spring for lining, making the entire circumference, the foot areas being closed per se. and a number of corresponding slots oriented, radially outward, ensuring a subdivision into individual spring zones, coming to marry each time, at the periphery, alternately one or the other of the spring rings for packing. According to another variant, as shown in principle in FIGS. 1 and 2, springs for individual linings, however separated from each other, can be provided at the periphery, each spring 10 for individual linings having only one curvature,

  oriented in one direction or the other.

  Thanks to the possibilities of realization described below

  above, it can be ensured that, for example, during "energetic starting processes", the mean effective radius is displaced in the radially outer zone of the friction lining rings, so that the rotational torque that can be transmitted is particularly high Thus, the torque transmission capacity during the starting process is significantly increased and the clutch tends to slip less, which also has a positive influence on the wear of the linings Simultaneously it is ensured that the disc clutch fitted with these lining springs has a very low inertia, which increases the capacity for maneuvering and the life of the gearbox

speed upstream.

Claims (9)

  1 clutch disc for a friction clutch for a motor vehicle, comprising: a hub (2), centered with respect to the axis of rotation (4), for mounting on a gearbox shaft, a disc part ( 3), concentric with respect to the hub (2), an arrangement of springs for packing, with an axially oriented elastic effect, connected to the disc part (3), in the region of the outer periphery of the latter, two packing rings friction (5), arranged axially back-to-back, on both sides of the packing spring arrangement, fixed to the packing spring arrangement, the packing spring arrangement having several packing springs (6 ) distributed in the peripheral direction, each of which has with respect to the axis of rotation (4) a flat bearing area (10), located radially outside a foot area (13) connected to the part of disc (3), intended to carry and f attach one of the two friction lining rings (5), and has a bearing zone (11, 12), folded in the direction of the other of the two friction lining rings (5), characterized in that the support zone (11, 12) of each lining spring (6) is arranged radially outside its plane bearing zone (10), reaches the other friction lining ring (5) , by means of a connection zone (11) extending obliquely to the axis of rotation, and has an end zone (12), projecting substantially radially, on which the other ring bears friction lining (5), and in that the lining springs (6) are arranged one behind the other individually in the direction   peripheral, with their alternating curvatures.   2 clutch disc according to claim 1, characterized in that the flat bearing zone (10) of each lining spring (6) is connected to the foot zone (13), by means of a zone of additional connection (14), located radially inside and extending obliquely to the axis of rotation, and in that the connection area (11) radially outside is longer in the axial direction than the connecting zone (14) extending radially inside. 3 clutch disc according to claim 2, characterized in that the connection zone (13) situated inside is configured so that the foot zone (13) extends at least approximately at mid-distance between the two friction lining rings (5), when the   gasket spring (6) is relaxed.   4 Clutch disc according to one of   Claims 1 to 3, characterized in that the springs   for trim (6) are separated from each other and have foot areas (13) separated from each other. 5 Clutch disc according to one of   claims 1 to 3, characterized in that several   lining springs (6) which are adjacent in the peripheral direction have foot zones (13) connected together in one piece and separated from each other by at least one slot (15) extending substantially radially, reaching radially internally up to to the foot area (13). 6 clutch disc according to one of claim 5, characterized in that each of the pairs of springs for lining (6) with opposite curvature is connected together in one piece by these foot areas (13).   7 clutch disc according to claim, characterized in that the foot areas of the set of springs for lining (6) are connected in one holding on to form a ring.   8 clutch disc according to claim 1 to 7, characterized in that the flat bearing area (10) of each lining spring (6) is connected to the foot area (13), by means of a additional connection zone (14), extending radially inside and obliquely to the axis of rotation, and in that the radially external connection zone (11) is of dimension allowing greater elastic resistance   as the radially inner connection zone (14).   9 Clutch disc according to one of   Claims 1 to 8, characterized in that each ring   of friction lining (5) is fixed, approximately in the middle of its radial extent, each time by means of a lining rivet (7), on the flat bearing zones (10), being axially adjacent thereto, springs for gasket (6).