Abstract: A clutch for a motor vehicle having an annular diaphragm (54) with a concave clutch characteristic curve and a pneumatic actuator (76) acting on the diaphragm (54) for clutch release. A mechanism (86, 88) is provided to generate a supplemental resistant force during clutch release to that developed by the diaphragm (54). The invention is particularly applicable to industrial vehicles equipped with a pressurized gas source.

Abstract: A friction clutch comprising a pressure plate (12) consisting of tow half-plates (12A, 12B) integral in rotation with the input shaft but axially mobile, relative to each other, under the action of the device compensating play due to wear. The wear compensating device comprises a pair of complementary ramps (17, 18) circumferentially arranged, axially associated respectively with each of the half-plates (12A, 12B), one support ramp (17) being integral in rotation to one (12B) of the half-plates, the other adjustment ramp (18) being adapted to move circumferentially relative to the support ramp (17) in the compensating direction increasing the global thickness of the first plate (12) and prevented form moving in the other direction by one-way means (24). The circumferential movement is controlled by a tripping element (22) sensitive to wear condition, the adjusting ramp (18) being arranged at the periphery of an inertial piece (12A).

Abstract: The invention concerns a clutch, in particular for a motor vehicle, comprising an annular diaphragm (54) with concave clutch characteristic curve and a pneumatic actuator (76) acting on the diaphragm (54) for clutch release, means (86, 88) being provided to generate during clutch release a resistant force which supplements that developed by the diaphragm (54). The invention is particularly applicable to industrial vehicles equipped with a pressurized gas source.

Abstract: The invention concerns a friction clutch for a heat engine motor vehicle, comprising a reaction plate (13), a friction disc (14), a pressure plate (12), a cover (11), the pressure plate (12) consisting of two half-plates (12A, 12B) integral in rotation with the input shaft but axially mobile, relative to each other, under the action of a device compensating play due to wear which comprises a pair of complementary ramps (17, 18) circumferentially arranged, axially associated respectively with each of the half-plates (12A, 12B), one of the ramps (17) called support ramp being integral in rotation to one (12B) of the half-plates, the other ramp (18) called adjustment ramp, being adapted to move circumferentially relative to the support ramp (17) in the direction increasing the global thickness of the first plate (12), called compensating direction, and prevented from moving in the other direction by one way means (24), said circumferential movement being controlled by a tripping element (22) sensitive to wear co

Abstract: A motor vehicle friction clutch, including a reaction plate, a friction disc with friction liners at its outer periphery, a pressure plate, a cover plate, axial clutch engaging mechanism controlled by declutching and acting between the cover plate and the pressure plate through respective primary and secondary abutments, the pressure plate being fixed to the cover plate that is axially displaceable for rotation with the latter, also includes a wear compensating device. One of the abutments when the clutch is engaged is displaceable axially and the compensating device is brought into operation to effect the displacement. The actuating device is controlled by a displacement in association with a detection responsive to wear in the liners and acting on at least one of the elements consisting of the actuating, compensating and displacement means. Adjustment of the nominal position of the clutch when engaged defined by the axial distance between the primary and secondary abutments when the clutch is engaged.

Abstract: The invention concerns a clutch friction, comprising a reaction plate (202) designed to be locked in rotation on an input shaft a friction disk (200), bearing at its external periphery at least one friction lining (201), designed to be locked in rotation on an output shaft, a pressure plate (1), a cover (2) fixed on the reaction plate (202), clutch means with axial action (3) controlled by releasing means and which operate between the cover (2) and the pressure plate (1) via support means (14), the pressure plate (1) being interlocked in rotation with the cover (2) while being capable of moving axially relative thereto and subjected to the action of elastic return means returning the pressure plate (1) axially towards the cover (2).

Abstract: A motor vehicle friction clutch, comprising a reaction plate, a friction disc with friction liners at its outer periphery, a pressure plate, a cover plate fixed on the reaction plate, axial clutch engaging means controlled by declutching means and acting between the cover plate and the pressure plate through respective primary and secondary abutments, with the pressure plate being fixed to the cover plate for rotation with the latter while being axially displaceable with respect to it, also includes a wear compensating device. One of the abutments of the clutch engaging means is displaceable axially and the compensating device includes a compensating means brought into operation by an actuating means which is arranged to effect this displacement. The actuating means is controlled by a displacement means in association with a detection means responsive to wear in the liners and acting on at least one of the elements consisting of the actuating, compensating and displacement means.

Abstract: The clutch mechanism for friction clutch comprises a reaction plate, a friction disk (7), a pressure plate (1), a cover (2), clutching means (3), operating axially and controlled by declutching means, operating between the cover (2) and the pressure plate (1) through support means (14), the pressure plate (1) being integral in rotation with the cover (2) while being capable of moving axially relative to it. Said clutch also comprises a wear take-up device comprising ramp means (11), with ramps (15) axially set between the support means (14) and the pressure plate (1), said ramps (15) being adapted to co-operate with counter-ramp means (4) while stop means (20) borne by the cover (2) are provided and adapted to limit the travel of the clutching means (3), in a position for storing the mechanism in the proximity of their operative position.

Abstract: The friction clutch comprises a friction disc, a pressure plate (1), a cover plate (2), a diaphragm (3) working between, firstly, the cover plate (2) and secondly the pressure plate (1), the said clutch also including a wear compensating device comprising ramps (11) disposed circumferentially and adapted so as to be driven in rotation by means of a set of teeth (18) which they carry at their periphery and with which a tangentially disposed worm (13) cooperates, a ratchet wheel (20) for driving the worm (13) in rotation being provided and rendered operational by wear in the friction liners when the clutch is engaged, together with non-return catches (36) for preventing the worm (13) from turning in the direction opposite to that in which it is driven in rotation by the ratchet wheel when it is operational, the worm (13), the non-return catches (36) and the ratchet wheel (20) being carried by a support (12) fixed to the cover plate (2): the ratchet wheel (20) of the worm (13) is controlled by the diaphragm (3).

Abstract: The invention concerns a friction clutch comprising a reaction plate, a friction disk, bearing at its external periphery friction linings, a pressure plate (1), a cover (2) fixed on the reaction plate, elastic means operating axially (3) between the cover and the pressure plate (1) through support means (14), a wear take-up device including ramp means (11) axially set between the support means (14) and the pressure plate (1), said ramps (15) being adapted to co-operate with counter-ramp means (4). Said wear take-up device further comprises a toothing (18) with which a worm (13) co-operates, the counter-ramp means (4) being integral with said toothing (18) and means (20) driving the worm (13) in rotation being provided, the worm (13) and the means (20) driving the worm (13) in rotation being borne by a support (12) integral with the ramp means (11).

Abstract: The friction clutch comprises a friction disc, a pressure plate (1), a cover plate (2), and an axially acting spring (3) working between the cover plate (2) and the pressure plate (1), the pressure plate (1) being fixed in rotation to the cover plate (2) while being able to be displaced axially with respect thereto, the said clutch also including a wear compensating device comprising ramps disposed circumferentially and located and adapted so as to be driven in rotation by means of a set of teeth (18) which they carry at their periphery and with which a worm (13) cooperates, a ratchet wheel (20), fixed in rotation to the worm (13), being provided, together with a non-return catch (36) for preventing the worm (13) turning in the direction opposite to that in which it is driven in rotation by the ratchet wheel (20): the non-return catch (36) is part of a resilient member (31) which also carries a control tongue (35) for actuating the ratchet wheel (20) in rotation.

Abstract: A declutching device, especially for a motor vehicle clutch of the pull-off type, comprises an hydraulic actuator. The latter comprises a fixed member and a movable member in piston and cylinder relationship, defining a control chamber between them, together with preloading force for biassing the movable member of the hydraulic actuator permanently towards one of its end positions with respect to the fixed member of the actuator. The supply of hydraulic fluid to the control chamber is under the control of a valve, which is for example incorporated in a boss which is part of the fixed member of the hydraulic actuator. The valve has a movable valve member which is in communication with the control chamber on one side, and which is biassed by a spring on the opposite side of the valve member.

Abstract: A declutching device comprises an hydraulic actuator, a preloading spring which permanently bias the movable member of the hydraulic actuator towards its retracted position with respect to the fixed member of the actuator, and a retaining element for retaining the movable member in its extended position with respect to the fixed member. The retaining element comprises a locking ring which is held under precompression in a groove formed in the movable member of the actuator, while another groove, with a stepped base, is formed in the fixed member of the actuator. The base of this latter groove comprises at least two steps, offset axially from each other and having different diameters, namely a first step for holding the locking ring at least partially engaged in the groove of the movable member, and a step which is adapted to enable it to escape automatically from this groove.

Abstract: A declutching device for a clutch of the pull-off type, especially for a motor vehicle, comprises an hydraulic actuator, a preloading coil spring which permanently biasses the movable member of the hydraulic actuator towards its retracted position into the fixed member of the actuator with which the movable member is in piston and cylinder relationship, and a retaining element for holding the movable member in its extended position with respect to the fixed member until the declutching device has been properly snap-fitted on to the clutch. The preloading spring is indexed angularly on the fixed member and on the movable member, and the retaining element comprise a lug, which is fixed to one of the two actuator members and engages with an angle element fixed to the other actuator element, so as to provide axial and circumferential abutment between the two actuator members in a predetermined relative angular position of these latter, and such as to put the spring into torsional prestress.