A composite hybrid gear assembly includes a gear hub formed from a composite material and a gear head assembly. The gear hub includes a shaft region having an axially symmetrical external profile and a hub web region having a flared profile extending from the shaft region. The gear head assembly includes a head web region and a teeth region where the gear head assembly is fixed to the gear hub. Additionally, the composite hybrid gear assembly includes a first sleeve fixed to an external surface of the shaft region. An associated method of making a composite hybrid gear assembly is also provided.

This gear wheel mechanism includes a rotator, a first gear wheel, a second gear wheel, and a reinforcement member. The rotator is configured to be rotatable about a rotation shaft and has an elliptical shape as viewed in an axis direction of the rotation shaft. The first gear wheel includes a first base portion including a first outer circumferential surface and a first inner circumferential surface and having a hollow cylindrical shape configured to be deformable by the rotator being inserted in the axis direction of the rotation shaft and external teeth formed in the outer circumferential surface. The second gear wheel includes a second base portion including a second outer circumferential surface and a second inner circumferential surface and having a hollow cylindrical shape disposed to cover the external teeth and internal teeth which are formed at positions facing the external teeth of the second inner circumferential surface, with which the external teeth are partially engaged in accordance with deformation of the first base portion by rotation of the rotator. The reinforcement member is disposed in contact with a region of the second outer circumferential surface corresponding to a region in which the internal teeth of the second inner circumferential surface are formed.

A rotating component includes a metal plate fixed to an end portion of the metal shaft, and a resin valve gear integrally formed with the plate by insert molding. The plate is formed with a circular fitting hole that fits with the end portion of the shaft, and a positioning recess that is recessed from one side to the other side of the plate.

Provided is a method for producing a gear including an intermediate product forming process of solidifying a fluid material to form a gear intermediate product, and a tooth forming process of cutting the gear intermediate product to form teeth.

Provided is a method for manufacturing a rotary power transmission member including a ring-shaped main body part fixed to a rotating shaft, and a ring-shaped gear part formed on an outer circumference part of the main body part to transmit rotational force of the rotating shaft to other members. The method includes gear part molding for injecting a high melting point resin into a first mold to mold the gear part, and main body part molding for injecting a low melting point resin to mold the main body part while the gear part being inserted into a second mold. The first mold includes a runner defined on an inner circumference side of a ring-shaped cavity for molding the gear part, and a gate which communicates the runner with the cavity to supply a resin into the cavity.