Plural ejector pins are made to project before a molten resin containing reinforcing fibers is injected into an inside of a cavity through pin point gates in a web forming portion in the inside of the cavity and at positions outside the pin point gates in a radial direction. The ejector pins are retracted from the inside of the cavity after a flow of the molten resin containing reinforcing fibers injected into the inside of the cavity through the pin point gates impinges on the ejector pins and is divided and before a tooth portion forming portion in the inside of the cavity is filled with the molten resin containing reinforcing fibers. Accordingly, weld lines which extend along the radial direction are formed at positions outside the ejector pins in the radial direction, and the molten resin is filled in portions formed after the ejector pins are retracted.

A case includes a first member and a second member configured in such a way that a closed space is formed between the first and second members in a state where the first and second members abut against each other. The first member includes a shaft portion extending toward the second member. The second member includes a shaft support portion including a circumferential wall portion that surrounds one end portion of the shaft portion. The shaft portion includes an enlarged-diameter portion that is the one end portion melted in such a way as to be enlarged in diameter.

A light-weight gear including: an annular tooth portion made of metal; a shaft extending along a central axis of the tooth portion and made of metal; and a coupling element configured to couple the shaft to the tooth portion and made of a resin, in which a joining part between the shaft and the coupling element and a joining part between the tooth portion and the coupling element are provided with irregularities configured to be engaged with one another in a circumferential direction, and corners of the irregularities are rounded to release a stress. Also, provided is a manufacturing method of a light-weight gear including: disposing the tooth portion and the shaft in a mold and injecting a molten resin into a cavity of the mold, thereby simultaneously performing injection molding of the coupling element and joining the coupling element to the tooth portion and the shaft.

A gear manufacturing method, the gear including an annular gear portion including teeth on an outer periphery, an annular support portion provided on an inner peripheral surface of the gear portion and supporting the gear portion, and a core portion provided inside the support portion, the method includes: a support portion molding step of molding the support portion by disposing the gear portion and the core portion in an annular mold and filling a resin between the gear portion and the core portion; and a support portion cooling step of cooling the support portion molded in the support portion molding step, a radial gap between the teeth of the gear portion and the mold before the support portion molding step is set to be smaller than a radial shrinkage amount of the support portion in the support portion cooling step.

An assembling apparatus that has a mold in which a second unit opposes a first unit and that is configured to assemble an assembled product from a plurality of parts. The first unit includes first, second, and third movable portions, which comprise, respectively, a plurality of first forming portions, a plurality of second forming portions, and a plurality of third forming. The second unit comprises a fourth movable portion, a fourth forming portion, a fifth forming portion, a sixth forming portion, and a plurality of assembling portions. The fourth movable portion is configured to move so as to switch at least one assembling portion opposed to at least one first forming portion, at least one other assembling portion opposed to the at least one second forming portion, and at least one remaining assembling portion opposed to at least one third forming portion.

An aspect of mold for producing an end plate of a planetary gear carrier includes a mold body and a cylindrical protrusion extending from a front surface of the mold body. The cylindrical protrusion defines a cylindrical interior space fluidly linked to an interior space of the mold body. The mold also includes an injection gate disposed on a rear surface of the mold body and aligned with a longitudinal axis of the cylindrical protrusion, wherein the injection gate is configured to allow an injection nozzle to inject a molding material into the interior space from an exterior of the mold body. In some aspects, the molding material includes additives that can improve the properties of the resulting molded part. Other aspects of the present disclosure include molded carriers for planetary gear devices, and related processes or methods for making similar molded parts.

A light-weight gear including: an annular tooth portion made of metal; a shaft extending along a central axis of the tooth portion and made of metal; and a coupling element configured to couple the shaft to the tooth portion and made of a resin, in which a joining part between the shaft and the coupling element and a joining part between the tooth portion and the coupling element are provided with irregularities configured to be engaged with one another in a circumferential direction, and corners of the irregularities are rounded to release a stress. Also, provided is a manufacturing method of a light-weight gear including: disposing the tooth portion and the shaft in a mold and injecting a molten resin into a cavity of the mold, thereby simultaneously performing injection molding of the coupling element and joining the coupling element to the tooth portion and the shaft.

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.

Over an outer peripheral surface of a sleeve, a primer layer is formed that is a thermoplastic resin-based adhesive thermally melted at a temperature lower than a melting point of a thermoplastic resin formed into a resin member to exhibit adhesiveness. With the sleeve preheated, a thermoplastic resin to be formed into the resin member is annularly injection-molded over an outer periphery of the sleeve.

The present invention is intended to provide a manufacturing method of an insert molded article that makes it possible to manufacture efficiently the insert molded article including a metallic insert, an inside member made of a synthetic resin and covering a portion of the insert, and an outside member made of a synthetic resin different from the material of the inside member and covering a portion of the inside member using general molding machines, not a dedicated two-color molding machine.

General molding machines are used to manufacture the insert molded article formed by injection molding of a resin part in twice. An insert core 7 is used in common in primary molding using a primary molding die C1 and in a secondary molding using a secondary molding die. A round shaft 7C of the insert core 7 is fitted into an internal hole 2C of an insert 2 to form a coupled body 10 in which the insert 2 and the insert core 7 are coupled together. The coupled body 10 is used in common at the primary molding step and the secondary molding step.