A transmission includes an input drive shaft, a drive gear, an idler gear, and a driven gear. The drive gear is rotationally fixed to the input drive shaft which, in turn, may but not necessarily, be powered by an engine. The idler gear may include a second set of gear teeth mounted to a bearing wherein the second set of gear teeth are formed from polymeric material. The second set of gear teeth for the idler gear may be in meshing engagement with the first set of gear teeth. The driven gear may include a third set of gear teeth in meshing engagement with the second set of gear teeth. The driven gear may be rotationally fixed to a pump shaft for a transmission pump. The input drive shaft, the drive gear, the idler gear, and the driven gear are configured to power a transmission pump.

Toothed belt drive with a toothed belt and at least two toothed pulleys, wherein the toothed belt has at least one drive side provided with a toothed profile, the toothed belt wraps around the toothed pulleys over a partial area of their circumference and the teeth of the toothed belt meshingly engage in the tooth gaps of the toothed pulleys, wherein at least one of the toothings on the belt or pulley is formed as a series of tooth pitches varying along the circumference, wherein the individual tooth pitches are designed to vary by up to a maximum of 5% relative to the mean tooth pitch on the belt or pulley, and the absolute deviation of a varied tooth pitch from the mean tooth pitch on the belt or pulley is limited by the backlash of the toothing,
wherein the backlash E.sub.S results from the difference of the width e.sub.S of the tooth gaps of the respective toothed pulley and the width e.sub.R of the teeth of the toothed belt in the middle of the tooth height of the teeth of the toothed belt.

The present device includes gears with bending compliance in the outer portion of the gear teeth to reduce gear noise. The present device reduces the variation in gear stiffness by introducing bending compliance in the outer portion of the gear tooth, by way of a cutout or relief area in the distal end of the tooth.

The present device includes gears with bending compliance in the outer portion of the gear teeth to reduce gear noise. The present device reduces the variation in gear stiffness by introducing bending compliance in the outer portion of the gear tooth, by way of a cutout or relief area in the distal end of the tooth.

A method for manufacturing a gear which effectively prevent a crack from occurring inside a tooth part when rolling processing is performed on a teeth part of a gear raw material is achieved. A method according to one embodiment for manufacturing a gear by performing rolling processing on a tooth part of a sintered gear raw material. The method includes, when the rolling processing is performed on the tooth part of the gear raw material, pressing the gear raw material toward a center of rotation of the gear raw material by a rolling machine and, when at least the rolling processing is performed on the tooth part of the gear raw material toward a center of a thickness thereof by a pressing machine, pressing a region where an internal density of the tooth part of the gear raw material decreases.

A method for manufacturing a gear which effectively prevent a crack from occurring inside a tooth part when rolling processing is performed on a teeth part of a gear raw material is achieved. A method according to one embodiment for manufacturing a gear by performing rolling processing on a tooth part of a sintered gear raw material. The method includes, when the rolling processing is performed on the tooth part of the gear raw material, pressing the gear raw material toward a center of rotation of the gear raw material by a rolling machine and, when at least the rolling processing is performed on the tooth part of the gear raw material toward a center of a thickness thereof by a pressing machine, pressing a region where an internal density of the tooth part of the gear raw material decreases.

A flat strain wave gearing (1) has a mechanism for preventing a flexible externally toothed gear (4) from moving in the direction of the device center axis (1a) with respect to a rigid internally toothed gears (2, 3). The mechanism has an inner-peripheral groove (11) formed on inner teeth (3a) of the internally toothed gear (3), an outer-peripheral groove (12) formed on outer teeth (4a) of the externally toothed gear (4), and a flexible ring (13) mounted between the inner-peripheral groove (11) and the outer-peripheral groove (12). The ring (13) is engageable with groove inner-peripheral surfaces (11a, 11b, 12a, 12b), from the direction of the device center axis (1a), at meshing positions of the both gears (2, 4).

A flat strain wave gearing (1) has a mechanism for preventing a flexible externally toothed gear (4) from moving in the direction of the device center axis (1a) with respect to a rigid internally toothed gears (2, 3). The mechanism has an inner-peripheral groove (11) formed on inner teeth (3a) of the internally toothed gear (3), an outer-peripheral groove (12) formed on outer teeth (4a) of the externally toothed gear (4), and a flexible ring (13) mounted between the inner-peripheral groove (11) and the outer-peripheral groove (12). The ring (13) is engageable with groove inner-peripheral surfaces (11a, 11b, 12a, 12b), from the direction of the device center axis (1a), at meshing positions of the both gears (2, 4).

This anti-backlash gear includes a gear wheel and gear teeth. Each gear tooth comprises first and second flanks, a top face and a bottom face, wherein for each gear tooth each flank extends from the top face to the bottom face, wherein the gear teeth comprise a polymeric material which comprises a repeat unit of form I wherein t1, and w1 independently represent 0 or 1 and v1 represents 0, 1 or 2. For each gear tooth, at least one of said flanks comprises two or more surfaces arranged to form a single protrusion extending along the at least one said flank such that a tooth thickness of each gear tooth varies between the top face and the bottom face of said gear tooth in a direction parallel to an axis of rotation of the gearwheel in operation. In use, the single protrusion is elastically deformable so as to absorb backlash.

This anti-backlash gear includes a gear wheel and gear teeth. Each gear tooth comprises first and second flanks, a top face and a bottom face, wherein for each gear tooth each flank extends from the top face to the bottom face, wherein the gear teeth comprise a polymeric material which comprises a repeat unit of form I wherein t1, and w1 independently represent 0 or 1 and v1 represents 0, 1 or 2. For each gear tooth, at least one of said flanks comprises two or more surfaces arranged to form a single protrusion extending along the at least one said flank such that a tooth thickness of each gear tooth varies between the top face and the bottom face of said gear tooth in a direction parallel to an axis of rotation of the gearwheel in operation. In use, the single protrusion is elastically deformable so as to absorb backlash.