A hysteresis torque generating mechanism includes a first rotor having a slide surface, and a second rotor opposed to the first rotor. The second rotor is configured to slide against the slide surface of the first rotor so as to generate a hysteresis torque. The second rotor includes an initial contact portion and a main friction surface. The initial contact portion is provided to protrude toward the first rotor. The initial contact portion is configured to slide in contact with the slide surface of the first rotor. The main friction surface is configured to slide in contact with the slide surface of the first rotor after abrasion of the initial contact portion.

A ring gear that, together with a sun gear and a pinion gear that is disposed radially outward of the sun gear and meshes with the sun gear, forms a planetary gear unit, the ring gear includes: a body, internal teeth that are configured to mesh with the pinion gear and that are formed in at least a part of an inner peripheral surface of the body, and external teeth that have a lower hardness than the internal teeth and that are formed in at least a part of an outer peripheral surface of the body, wherein a surface nitrogen concentration in the internal teeth is higher than that in at least tooth surfaces of the external teeth.

Assembly for synchronization unit of gear-changing transmission includes a friction ring and synchronizer ring. Friction ring has a conical friction ring body with friction surface and an installation surface that respectively bound friction ring body in a radial peripheral direction extending perpendicular to an axial friction ring axis. Friction surface extends at a predefinable friction angle and installation surface extends at a predefinable installation angle, in each case conically. Synchronizer ring has a contact surface corresponding to installation surface of friction ring. Synchronizer ring and friction ring are adapted so that contact surface of synchronizer ring contacts installation surface of friction ring, and friction surface of friction ring is in rubbing contact with a gear wheel during a synchronization process where synchronizer ring is displaced in a direction of a gear wheel to be synchronized. Installation surface of friction ring and/or contact surface of synchronizer ring has/have adhesion-reducing surface structure.

A number of variations may include a product including a single clutch pack having a plurality of clutch plates, and a first friction material on a first plate of the plurality of clutch plates, and a second friction material on a second plate of the plurality of plates, the first friction material being different than the second friction material, and constructed and arranged to provide a tailored combination of torque capacity and response time that would be produced by a clutch pack having solely the first friction material on plates thereof or the second friction material on plates thereof.

One exemplary aspect of the present disclosure relates to a method of forming a friction material. The method includes depositing a plurality of particles on a substrate such that the particles provide a plurality of projections and channels between adjacent projections. This disclosure also relates to the friction material itself, and a system including a mechanical component and the friction material.

A device that employs shear forces to transmit energy includes an outer housing assembly, a disk, and a reservoir with a working fluid. The disk is received in and rotatable relative to the outer housing assembly. A working cavity is formed between a rotor portion of the disk and the outer housing assembly into which the working fluid is received to create shear forces. A plurality of flow altering structures are disposed on the outer housing assembly and are configured to reduce a thickness of a boundary layer of the working fluid in the working cavity in areas that are local to the flow altering structures.

A method of making a wet friction material includes providing an outer layer on a base layer to form the wet friction material. The base layer includes a first proportion of fiber material and a first proportion of filler material. The outer layer includes a second proportion of fiber material and a second proportion of filler material. The second fiber proportion is less than the first fiber proportion and the second filler proportion is greater than the first filler proportion. The method further includes forming a modified outer layer by burning off the fiber material of the outer layer.

A device that employs shear forces to transmit energy includes an outer housing assembly, a disk, and a reservoir with a working fluid. The disk is received in and rotatable relative to the outer housing assembly. A working cavity is formed between a rotor portion of the disk and the outer housing assembly into which the working fluid is received to create shear forces. A plurality of flow altering structures are disposed on the outer housing assembly and are configured to reduce a thickness of a boundary layer of the working fluid in the working cavity in areas that are local to the flow altering structures.

In a locking type reverse input blocking clutch, smooth finished surfaces having no directionality are formed, by barrel polishing, on surfaces brought into contact with rollers while rotation is being transmitted from the input side to the output side, i.e. an inner peripheral cylindrical surface of an outer ring and a surface of a lid portion opposed to the rollers. With this arrangement, it is possible to reduce the sliding resistance between the rollers and the outer ring and between the rollers and the lid portion, without the need to reduce the forces of springs for pushing the rollers into narrow portions of wedge-shaped spaces. This in turn makes it possible to reduce the torque necessary to transmit rotation from the input side to the output side, while maintaining high locking performance.

A shaft structure installed in a shaft capable of making a power-transmission, the shaft structure including: a male component having a plurality of male splines formed on an outer peripheral part thereof; and a female component having a plurality of female splines formed on an inner peripheral part thereof, the inner peripheral part configured to allow the outer peripheral part of the male component to be engaged therein so that the male component and the female component can be slidably fitted with respect to each other in an axial direction thereby making up said shaft structure, wherein the outer peripheral part of the male component and the inner peripheral part of the female component have a fabric impregnated with rubber or resin interposed therebetween.