A power train component such as a gearbox includes driving and driven, coaxially arranged cooperating gears which engage each other via teeth. The engaging end surfaces of the teeth are provided with a first chamfer and a second chamfer, in which the chamfer edge is offset from bisecting the tooth. Preferably the offset chamfer edges are provided on both a driving gear (shifter), axially positionable using a shifting fork on a shift drum, and a driven low gear. In one preferred driving gear (shifter) design, the offset chamfer edges are only provided for the side engaged when the shifting fork moves against a spring force. The invention facilitates smoother and less binding movement between the non-engaged and the engaged axial positions, such that the gear can be more easily shifted by the shifting fork in at least one direction.

A hollow reducer for high precision control includes a pin wheel housing and two-stage reduction components disposed in the pin wheel housing. A first-stage reduction component includes a driving wheel on a servo motor, a dual gear, and a planet wheel; and a second-stage reduction component includes 2-3 eccentric shafts distributed uniformly, cycloidal gears, a pin, rigid disks, and bearings, wherein two eccentric sections of the eccentric shaft support the cycloidal gears by means of the bearings, shaft extensions on two sides of the eccentric section of the eccentric shaft are supported on the left and right rigid disks by the bearings, and the rigid disks are supported on two sides of the pin wheel housing by the bearings.

A reducer for high precision control includes a pin gear housing and two-stage reduction components disposed therein: a first-stage reduction component including an input shaft, a sun gear and a planet gear; and a second-stage reduction component including 2-3 eccentric shafts distributed uniformly, cycloidal gears, a pin, a left rigid disk and a right rigid disk, and bearings, wherein the cycloidal gears are supported by bearings on two eccentric sections of the eccentric shaft, shaft extensions on two sides of the eccentric section of the eccentric shaft are supported by bearings on the left rigid disk and the right rigid disk, and the left rigid disk and the right rigid disk are supported by bearings in inner holes of two sides of the pin gear housing.

A bicycle sprocket includes a first sprocket body and a plurality of first sprocket teeth. The first sprocket teeth include a plurality of tooth tip portions and a plurality of tooth bottom portions. The tooth bottom portions include at least one first tooth bottom portion and at least one second tooth bottom portion. The at least one first tooth bottom portion has a first tooth bottom shape. The at least one second tooth bottom portion has a second tooth bottom shape. The first tooth bottom shape is different from the second tooth bottom shape.

A method of manufacturing a gear is provided. The method includes forming a plurality of gear teeth in a surface of a gear, the gear teeth having tooth faces defining tooth edges including tooth edge flanks and tooth edge top land and generating a convex contour at an edge break of at least one of the tooth edge flanks and tooth edge top land.

In a gear unit that includes a rotatably mounted toothed part and a method for manufacturing a gear unit that includes a toothed part, the toothed part has bearing seats and a toothing, and the toothed part, e.g., together with the toothing, is produced from sintered metal powder. The toothed part is, for example, arranged as one piece, e.g., in an integral fashion.

A reducer for high precision control includes a pin gear housing and two-stage reduction components disposed therein: a first-stage reduction component including an input shaft, a sun gear and a planet gear; and a second-stage reduction component including 2-3 eccentric shafts distributed uniformly, cycloidal gears, a pin, a left rigid disk and a right rigid disk, and bearings, wherein the cycloidal gears are supported by bearings on two eccentric sections of the eccentric shaft, shaft extensions on two sides of the eccentric section of the eccentric shaft are supported by bearings on the left rigid disk and the right rigid disk, and the left rigid disk and the right rigid disk are supported by bearings in inner holes of two sides of the pin gear housing.

A hollow reducer for high precision control includes a pin wheel housing and two-stage reduction components disposed in the pin wheel housing. A first-stage reduction component includes a driving wheel on a servo motor, a dual gear, and a planet wheel; and a second-stage reduction component includes 2-3 eccentric shafts distributed uniformly, cycloidal gears, a pin, rigid disks, and bearings, wherein two eccentric sections of the eccentric shaft support the cycloidal gears by means of the bearings, shaft extensions on two sides of the eccentric section of the eccentric shaft are supported on the left and right rigid disks by the bearings, and the rigid disks are supported on two sides of the pin wheel housing by the bearings.

A method of manufacturing a gear member formed into a cylindrical shape, the gear member having an internal gear disposed without overlapping the bearing holding portion in an axial direction, the method including: preparing a cylindrical material with a small-diameter cylindrical portion having an inner diameter corresponding to a tooth tip diameter of the internal gear in a tooth width region of the internal gear such that the small-diameter cylindrical portion is extended from the tooth width region toward the one end portion to reach the bearing holding portion; and inserting a skiving cutter from the other end portion side opposite to the one end portion of the cylindrical material to form the internal gear by skiving in the tooth width region of the small diameter cylindrical portion, and terminating the skiving at a halfway position before reaching the bearing holding portion and across the tooth width region.

A ratchet structure includes a body. The body is provided with a plurality of equally spaced ratchet teeth extending along the axial direction, and an annular groove is formed on the body to divide the body into a head portion and a body portion. The ratchet teeth are located on the body portion, and a predetermined groove is provided between the ratchet teeth and the annular groove. With the predetermined groove, when the milling cutter mills out the groove in the body portion and enters the predetermined groove, the waste chips connected to the annular groove bottom surface of the annular groove will be surely cut off, thereby solving the problem that it is difficult for the ratchet wheel to get rid of the waste chips.