A first shot body member includes a pair of side walls, a semi-circular sleeve positioned between the pair of side walls to define a portion of a longitudinal pocket, and a pair of deflecting wings. Each deflecting wing is coupled to one of the side walls at a corner. A second shot isolation member of an elastically resilient second material is bonded to portions of an interior surface of the longitudinal pocket defined by each of: the semi-circular sleeve, each of the pair of side walls, each of the pair of corners, and each of the pair of wings. Mold members can include supporting surfaces to support interior and exterior portions of the wing during the second shot molding operation, while leaving an exposed interior bonding surface that defines a portion of the second shot molding cavity. Related methods are further disclosed.

The present invention is intended to provide a method for manufacturing a resin gear with a core metal by which there is no reduction in strength even with gates allowing decrease in material costs such as pin gates in the molding die for injection molding.

The manufacturing method includes: gates at a primary molding step and gates at a secondary molding step are pin gates or the like. The number of the gates at the primary molding step and the number of the gates at the secondary molding step are plural and identical, and the gates are arranged circumferentially. Gate positions G21, . . . at the secondary molding step are circumferentially intermediate or nearly circumferentially intermediate between gate positions G11, . . . and weld positions W11, . . . adjacent to the gate positions G11, . . . in the primary molded article.

According to embodiments, provided is a support manufacturing method comprising the steps of: forming a first injection-molded product by using a first material; injecting a second material into at least a portion of the first injection-molded product; forming a second injection-molded product including a hollow by discharging the second material from the first injection-molded product; and forming a third injection-molded product by covering at least a portion of the outer surface of the second injection-molded product with a third material.

An injection molding apparatus for producing a plastics molding comprising a first component, a second component, and a third component comprises a first mold plate having at least 3 first mold nests, and a second mold plate having at least 3 second mold nests. In the closed state, the mold plates cooperate in the production of the plastics mold. In the opened state, the second mold plate is rotatable relative to the first mold plate. The at least 3 second mold nests comprise, in a case A), at least two second mold nests for injection molding the first component, and at least one second mold nest for injection molding the third component, or, in a case B), at least two second mold nests for injection molding the second component, and at least one second mold nest for injection molding the first component.