In a power transmission apparatus, an auxiliary clutch plate different in diameter from driving and driven clutch plates located in a clutch housing. When the driving and driven clutch plates are pressed against each other, the auxiliary clutch plate is pressed to enable transmission of a driving force of an engine to a driving wheel. When a pressing force exerted on the driving and driven clutch plates is released, a pressing force exerted on the auxiliary clutch plate is released to cut off transmission of the driving force of the engine to the driving wheel.

Some embodiments of a fan clutch system for use in a vehicle can provide efficient access to one or more components for inspection and service even after the fan clutch system is installed in the vehicle. In particular embodiments, the fan clutch system can include a fan clutch device and a coil retainer assembly that are removably mounted to a right-angle gear box assembly in a manner that permits a technician to accessing at least one component for inspection, repair, or replacement. The coil retainer assembly may at least partially house an electromagnetic coil for selective activation. The system may further include a fan clutch device removably mounted to the drive member of the gear box assembly.

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.

Methods of repairing a torque converter that enable the continued use of a torque converter and result in a repaired torque converter with a higher-strength and more durable construction. In some examples, a backing ring can be replaced with a replacement backing ring that includes a spline ring for replacing the function of a cover spline ring. In some examples, a method of repairing a torque converter can be improved by providing a replacement backing ring with a radial protrusion for locating the backing ring on the cover, and a method of determining an axial location of the radial protrusion.

Provided are a method for manufacturing a wet friction plate, whereby efficiency of the work of forming a fine groove on a friction material can be improved, the wet friction plate, and a wet multiple-plate clutch device having the wet friction plate. In the method for manufacturing a wet friction plate 200, a core metal 201 and a friction material 210 are prepared, a resin layer 203 is formed on the core metal, the friction material is attached onto the resin layer, and a fine groove 211 is formed in the friction material. Specifically, irradiation of a laser beam L is started on an exposed portion 205 of the core metal. A laser head 301 is displaced in an annular shape while continuously emitting the laser beam. Thus, annular fine grooves 204 and 211 are formed in the exposed portion of the core metal and the friction material.

A transmission of an internal combustion engine in which the shaft length of a main shaft can be shortened to eliminate a supporting wall around a reduction gear while a thrust load is received. Around a main shaft of a transmission of an internal combustion engine, a primary bearing is fastened to an inside of a primary driven gear, and is disposed between the primary driven gear and the main shaft. A collar member is disposed between the primary bearing and a main bearing. A step portion, in contact with the main bearing, is formed on the main shaft on an opposite side of the main bearing from the collar member. A cylindrical portion, an inner race of the primary bearing, the collar member, and an inner race of the main bearing are fastened to the side of the step portion.

A torque disc comprising a fixing surface and at least one restraining element. The fixing surface defines an area of the torque disc for attachment to a fastener in use, and the at least one restraining element extends from the fixing surface so as to engage in use with at least one portion of the fastener to restrain rotational movement of the fastener during attachment to or detachment from the torque disc.

A method is provided for manufacturing an outer ring of a constant velocity joint including an outer ring, an inner rotational member, a torque-transmitting rolling element, and a defining member. The outer ring includes: a first inner peripheral surface to which the defining member is attached; a second inner peripheral surface; and protrusions protruding radially inward of the first inner surface and the second inner peripheral surface so as to restrict axial movement of the inner rotational member and the rolling element. The manufacturing method includes: a plastic working step involving providing a base member; and a bottom removing step involving partially removing a bottom of the base member so as to form a through hole. The plastic working step further involves providing the second inner peripheral surface. The bottom removing step further involves providing the protrusions.

A shaft-hub connection with a shaft that includes a section with external splines, and a hub that includes internal. The hub with its internal splines is assembled in a positively joined manner with play on the section of the shaft including the external splines. The shaft in the section includes the external splines has a recess regularly inside of the external splines, in which a clamping body is inserted neutralizing the play between shaft and hub.

A constant velocity joint boot assembly includes a boot that may be positioned around a constant velocity joint on a vehicle. The boot has a longitudinal cut. Thus, the boot may be selectively placed around the constant velocity joint when the constant velocity joint is mounted to the vehicle. A zipper is coupled to the boot. The zipper closes the boot around the constant velocity joint. The zipper extends beyond the first end of the boot and the second end of the boot to define a pair of free ends of the zipper. Each of the free ends of the zipper is rolled up when the zipper is closed. Thus, the zipper may resist being contaminated thereby enhancing functionally of the zipper over time.