Provided is a method of manufacturing a resin retainer having two annular sections. A fixed-side cavity forming mold has a first axial mold surface that is in contact with an axial end surface of a first annular section of the annular sections of a resin retainer having two annular sections, and a first protruding portion protruding from the first axial mold surface. A movable-side cavity forming mold has a second axial mold surface that is in contact with an axial end surface of a second annular section of the annular sections of the resin retainer, and a second protruding portion protruding from the second axial mold surface. A slide core sliding step is performed in which slide cores are slid toward an outer diameter and pocket-forming protruding portions of the slide cores are extracted from a pocket of the retainer, and then a mold opening step is performed in which the movable-side cavity forming mold is opened relative to the fixed-side cavity forming mold.

Provided is a method of manufacturing a resin retainer having two annular sections. A fixed-side cavity forming mold has a first axial mold surface that is in contact with an axial end surface of a first annular section of the annular sections of a resin retainer having two annular sections, and a first protruding portion protruding from the first axial mold surface. A movable-side cavity forming mold has a second axial mold surface that is in contact with an axial end surface of a second annular section of the annular sections of the resin retainer, and a second protruding portion protruding from the second axial mold surface. A slide core sliding step is performed in which slide cores are slid toward an outer diameter and pocket-forming protruding portions of the slide cores are extracted from a pocket of the retainer, and then a mold opening step is performed in which the movable-side cavity forming mold is opened relative to the fixed-side cavity forming mold.

Two molded articles having a cylindrical two-piece split shape is formed by forming two primary cavities in a desired shape with molds assembled together and injecting a molten primary resin into the two primary cavities. An assist material is injected into a secondary cavity into which a molten secondary resin is injected in a state where the two molded articles are located opposed to each other via a space therebetween and internally fitted into one secondary cavity formed by the molds that are assembled together by shifting the positions. A flange portion having any desired shape is disposed on an outer circumferential surface of a resin pipe in a two-layer structure in which an inner surface layer formed of the cured secondary resin is integrated with an outer surface layer formed of the two molded articles. Thus, a portion having any desired shape is easily manufactured on the resin pipe.

Two molded articles having a cylindrical two-piece split shape is formed by forming two primary cavities in a desired shape with molds assembled together and injecting a molten primary resin into the two primary cavities. An assist material is injected into a secondary cavity into which a molten secondary resin is injected in a state where the two molded articles are located opposed to each other via a space therebetween and internally fitted into one secondary cavity formed by the molds that are assembled together by shifting the positions. A flange portion having any desired shape is disposed on an outer circumferential surface of a resin pipe in a two-layer structure in which an inner surface layer formed of the cured secondary resin is integrated with an outer surface layer formed of the two molded articles. Thus, a portion having any desired shape is easily manufactured on the resin pipe.

A toothed shaft can be installed in a hollow shaft that has an internal toothing such that the toothed shaft is coupled in a positively locking fashion so as to be telescopic in a direction of a longitudinal axis. The toothed shaft may include a toothing region with teeth on an outer circumference and extending in an axial direction. In the toothing region a shaft core may be overmolded by way of an injection molding process with a sliding coating comprised of thermoplastic material. The sliding coating may have at least three impressions, with each of the at least three impressions featuring an aperture that extends through the sliding coating to a surface of the shaft core.

A toothed shaft can be installed in a hollow shaft that has an internal toothing such that the toothed shaft is coupled in a positively locking fashion so as to be telescopic in a direction of a longitudinal axis. The toothed shaft may include a toothing region with teeth on an outer circumference and extending in an axial direction. In the toothing region a shaft core may be overmolded by way of an injection molding process with a sliding coating comprised of thermoplastic material. The sliding coating may have at least three impressions, with each of the at least three impressions featuring an aperture that extends through the sliding coating to a surface of the shaft core.

A tool for driving a threaded fastener includes a driver head, a motor, and an injector. The driver head includes a spindle rotatable about an axis. A distal end of the spindle defines a plurality of drive surfaces configured to engage mating drive surfaces on the fastener to rotate the fastener about the axis. The driver head defines a fluid passage having an outlet proximate to the distal end of the spindle. The motor is drivingly coupled to the spindle to rotate the spindle about the axis. The injector is coupled to an inlet of the fluid passage and configured to feed a liquid insulator through the fluid passage.

A manufacturing method of a polygonal mirror using a metal mold including a first mold, a second mold, a third mold, and a fourth mold includes a step of forming the molded member by providing the third mold and the fourth mold between the first mold and the second mold in a state in which the third mold and the fourth mold are in contact with each other and then by injecting a resin material into the metal mold, and a step of separating the third mold from the first crossing surface of the molded member in a direction crossing the first crossing surface.

An injection molding die includes a fixed die and a movable die that move in a die opening/closing direction relatively to each other. A cavity that is formed between the fixed die and the movable die in a die clamping state includes a lateral cavity portion that extends along the die opening/closing direction and a first orthogonal direction. The injection molding die includes a demolding core and a following core that define an end portion of the lateral cavity portion across the fixed die and the movable die in a second orthogonal direction. The demolding core and the following core are configured to be movable in the second orthogonal direction while defining the end portion of the lateral cavity portion across the fixed die and the movable die in the die clamping state, and to be engaged with the fixed die with substantially no play in the second orthogonal direction.

The disclosed embodiment is related to a manufacturing method of a die-formed 3-dimensional plastic impeller of a centrifugal pump and the impeller manufactured thereby, including a mold for twisted blade and a mold for impeller outlet, the mold for twisted blade is configured to form a twisted blade portion of each blade of the impeller, the mold for impeller outlet is configured to form a rear portion of each blade, a hub rim part of the impeller, and a shroud rim part of the impeller so that the hub rim part, the shroud rim part, and the blades are formed in a single piece at the same molding process.