Abstract: The present invention provides a method for manufacturing a closed impeller that has a simple configuration and enables fusion in a very accurate position. The method includes: forming a frustum-shaped front plate and a disk-shaped base plate formed therebelow, upper surfaces of a plurality of unit impeller blade plates made from a synthetic resin extending in radial directions which are formed as impeller blade tip surfaces, with sharp-pointed ridge-like protrusions having an acute upper end and a width less than a width of the impeller blade tip surface being integrally formed on the impeller blade tip surfaces. In the method, an inner surface of the front plate and the plurality of impeller blade tip surfaces are formed as parts of conical surfaces and formed so that the cone apex angles of the two conical surfaces are equal to each other.

Abstract: The present invention provides an impeller in which a metallic bush can be inserted correctly into a synthetic resin impeller main body manufactured by resin molding using a die, and a determination as to whether or not the impeller has been manufactured correctly can be made easily. The impeller comprises: a metallic bush comprising a circumferential boss portion having a substantially truncated cone-shaped throttle portion positioned on a front surface axial end side, a periaxial support boss portion positioned in an axial center, and a circumferential protruding portion positioned on a back surface axial end side; and an impeller main body made of synthetic resin and formed with a V-shaped bulging portion that bulges axially in the center of a front surface side of a disk-shaped vane portion fulcrum, in which a plurality of vanes are formed integrally on the periphery of the V-shaped bulging portion.

Abstract: The present invention provides a manufacturing method for an impeller with which molding and high-quality finishing can be performed extremely easily and quickly through resin molding using a die, and an impeller manufactured by the impeller manufacturing method. A metallic bush is disposed in a die, whereupon a resin material is injected through a gate in the die. A connecting portion between an unnecessary resin portion formed from residual resin material in the gate and a resin impeller main body molded around the bush is formed to be thin, and the unnecessary resin portion is removed from the impeller main body using pushing or withdrawing means.

Abstract: The present invention provides a method for manufacturing a closed impeller that has a simple configuration and enables fusion in a very accurate position. The method includes: forming a frustum-shaped front plate and a disk-shaped base plate formed therebelow, upper surfaces of a plurality of unit impeller blade plates made from a synthetic resin extending in radial directions which are formed as impeller blade tip surfaces, with sharp-pointed ridge-like protrusions having an acute upper end and a width less than a width of the impeller blade tip surface being integrally formed on the impeller blade tip surfaces. In the method, an inner surface of the front plate and the plurality of impeller blade tip surfaces are formed as parts of conical surfaces and formed so that the cone apex angles of the two conical surfaces are equal to each other.

Abstract: The present invention provides an impeller in which a metallic bush can be inserted correctly into a synthetic resin impeller main body manufactured by resin molding using a die, and a determination as to whether or not the impeller has been manufactured correctly can be made easily. The impeller comprises: a metallic bush comprising a circumferential boss portion having a substantially truncated cone-shaped throttle portion positioned on a front surface axial end side, a periaxial support boss portion positioned in an axial center, and a circumferential protruding portion positioned on a back surface axial end side; and an impeller main body made of synthetic resin and formed with a V-shaped bulging portion that bulges axially in the center of a front surface side of a disk-shaped vane portion fulcrum, in which a plurality of vanes are formed integrally on the periphery of the V-shaped bulging portion.

Abstract: The present invention provides a manufacturing method for an impeller with which molding and high-quality finishing can be performed extremely easily and quickly through resin molding using a die, and an impeller manufactured by the impeller manufacturing method. A metallic bush is disposed in a die, whereupon a resin material is injected through a gate in the die. A connecting portion between an unnecessary resin portion formed from residual resin material in the gate and a resin impeller main body molded around the bush is formed to be thin, and the unnecessary resin portion is removed from the impeller main body using pushing or withdrawing means.

Abstract: An impeller for a water pump includes an impeller main body composed of a synthetic resin and having a vane member formed around a rotating center portion; and a metal boss in which a circular boss member positioned on the forward side of the rotating center portion and provided with a gradually narrowing portion at the axial end thereof, and a periaxial support boss member positioned on the rearward side of the rotating center portion are consecutively formed in the axial direction, and in which an axial support surface is formed between the circular boss member and periaxial support boss member, the metal boss being insert-fitted into said rotating center portion.

Abstract: An impeller for a water pump in which a metal boss is insert-fitted into the rotating center portion of the impeller main body, and the area of the rotating center portion facing the impeller main body is fashioned to an adequate thickness, with the metal boss securely fitting into the impeller main body.

Abstract: A front fender for an automobile molded of a synthetic resin in a manner to provide an even flow of the resin to all portions of the fender in order to avoid points of weakness within the fender. The flow starts from numerous points along the fender arched wheel opening and eventually flows through a groove extending to the most radically remote portion of the fender to ensure flow thereto. Thickened cross-sections are formed along the arched wheel opening and the vertical rear edge of the fender for strength and impact resistance.

Abstract: An automobile door with an inner plate and an outer plate wherein the outer plate has a panel formed from a synthetic resin. The panel is attached to a rigid metallic plate, such as steel, through a plurality of fastening holes formed in the longitudinal direction of the synthetic panel. One of the fastening holes near the forward end of the panel has a diameter substantially that of the fastening means. The remaining fastening holes are formed so as to allow longitudinal expansion and contraction of the synthetic panel. A lip portion is formed near the lower edge of the synthetic panel to engage with the inner plate of the door.