Provided are a wet friction plate and a wet multiplate clutch device capable of reduction drag torque while suppressing a decrease in the area of a friction member. The wet friction plate includes multiple friction members through oil grooves on a flat plate annular core metal. The friction member has first fine grooves opening at an inner peripheral edge of the friction member and extending to an outer peripheral edge side and second fine grooves opening at an outer peripheral edge of the friction member and extending to an inner peripheral edge side. The first fine groove and the second fine groove are formed to have a groove width of equal to or greater than 0.1 mm and equal to or less than 0.8 mm, and overlap portions overlapping with each other in a circumferential direction at the same position in a radial direction of the core metal.

A vehicle transmission includes a first rotating element, second rotating element, first retainer ring, and second retainer ring. The first rotating element has an exterior surface that defines a first ring groove. The second rotating element is configured to limit movement of friction plates during clutch engagement. The second rotating element is disposed about the exterior surface and has an interior surface that defines a second ring groove. The first retainer ring is disposed in the first ring groove. The second retainer ring is disposed in the second ring groove and thereby restricts movement of the first retainer ring in a radially outward direction.

The invention comprehends friction plates, typically fabricated of metal, having friction material that is disposed in multiple concentric bands disposed in interrupted or discontinuous segments or a combination of both. In a first embodiment, the friction material is arranged in two concentric bands on each face, an inner band having a smaller radial width and an outer band having a larger radial width. In a second embodiment, the inner band is replaced with a plurality of discontinuous sections or segments wherein their circumferential separation is greater than their circumferential length. A third embodiment is similar to the second embodiment except that the inner, discontinuous segments have a circumferential length greater than their circumferential separation.

A Torsion damper wherein a first group of friction rings is supported in circumferential direction so as to be stationary with respect to the torque output part, and a second group of friction rings is supported in circumferential direction in the first swivel angle range so as to be moveable relative to the torque input disk and torque output disk, and in the second swivel angle range the second group of friction rings is supported in circumferential direction in a driving connection with respect to the torque input disk and executes a synchronous rotational movement with the torque input disk, wherein in the second swivel angle range a relative movement in circumferential direction takes place between the torque output disk and the second friction ring group, and a relative movement in circumferential direction takes place between the torque input disk and the first friction ring group.

A Torsion damper wherein a first group of friction rings is supported in circumferential direction so as to be stationary with respect to the torque output part, and a second group of friction rings is supported in circumferential direction in the first swivel angle range so as to be moveable relative to the torque input disk and torque output disk, and in the second swivel angle range the second group of friction rings is supported in circumferential direction in a driving connection with respect to the torque input disk and executes a synchronous rotational movement with the torque input disk, wherein in the second swivel angle range a relative movement in circumferential direction takes place between the torque output disk and the second friction ring group, and a relative movement in circumferential direction takes place between the torque input disk and the first friction ring group.

A torsion damper with at least one torque input disk and at least one torque output disk, wherein the torque input disk can move in circumferential direction relative to the torque output disk against the force of at least one spring storage, wherein the relative movement is damped by a friction device which generates a smaller friction torque in a first swivel angle range than in a second swivel angle range in that the friction device has at least two friction ring pairs which are rotatable opposite one another and which are activated depending on the swivel angle via a driving connection of at least one friction ring with the torque input disk. The driving connection has a spring element which is arranged functionally in series with the friction device and functionally in parallel with the spring storage.

A vehicle transmission includes a transmission shaft, a friction element assembly mounted on the transmission shaft, a piston assembly for actuating the friction element assembly, a snap ring for retaining the friction element assembly and a mounting groove formed in the transmission shaft. The snap ring is installed into the mounting groove by expanding the snap ring and then allowing the snap to contract and enter the mounting groove. The mounting groove is located such that the snap ring could exit the mounting groove upon expansion of the snap ring due to a centrifugal force. Accordingly, various arrangements are provided to prevent the snap ring from leaving the mounting groove after installation.

There is provided a method for producing a wet friction plate that can improve the retention property of lubricating oils in a fine groove formed by laser light. In a method for producing a wet friction plate (200), a friction material (210) is produced by sheet making processing in a first step. Thereafter, in a second step, a fine groove (211) is formed on the friction material (210). The friction material (210) is produced such that thermosetting resin therein is in a semi-cured state. The cross-sectional shape of the fine groove (211) is formed into a V shape by laser light. Subsequently, in a third step, the friction material (210) is disposed on a core metal (201) via an adhesive agent including thermosetting resin. Subsequently, in a fourth step, the friction material (210) is pressed while heated to crush the fine groove (211). In this manner, unevenness is formed on an intra-groove surface (212), and the thermosetting resin is completely cured.

The invention relates to a coupling device for a drive train of a motorcycle or other motor vehicle, in particular for suppressing a so-called hopping. According to the invention, the coupling device has an output rotation part, a switchable friction coupling, which has an energy storage device for closing thereof and which is closed in an unactuated state, and at least one freewheel coupling for forming a torque transmission path for torque transmission from the input rotating part to the output rotating part, wherein the freewheel coupling includes the following components: an inner rotating element, the outer circumference of which forms a sawtooth-shaped circumferential structure having a plurality of circumferentially extending ramps; a substantially annular plate structure having an individual plate element or a stack of a plurality of plate elements, the inner circumference of which forms a sawtooth-shaped circumferential structure having a plurality of circumferentially extending counter-ramps to form an interlock and/or a friction lock together with the ramps of the inner rotating element in a rotation direction; and an outer rotating element surrounding the plate structure. The invention further relates to a corresponding drive train having such a coupling device.

The invention relates to a coupling device for a drive train of a motorcycle or other motor vehicle, in particular for suppressing a so-called hopping. According to the invention, the coupling device has an output rotation part, a switchable friction coupling, which has an energy storage device for closing thereof and which is closed in an unactuated state, and at least one freewheel coupling for forming a torque transmission path for torque transmission from the input rotating part to the output rotating part, wherein the freewheel coupling includes the following components: an inner rotating element, the outer circumference of which forms a sawtooth-shaped circumferential structure having a plurality of circumferentially extending ramps; a substantially annular plate structure having an individual plate element or a stack of a plurality of plate elements, the inner circumference of which forms a sawtooth-shaped circumferential structure having a plurality of circumferentially extending counter-ramps to form an interlock and/or a friction lock together with the ramps of the inner rotating element in a rotation direction; and an outer rotating element surrounding the plate structure. The invention further relates to a corresponding drive train having such a coupling device.