Patent ID: 6117380
Filing Date: 2000-09-12
Classification: B29C,B29L,F02M,F05C

Abstract:
A method of manufacturing a synthetic resin tubular member having differently oriented inlet tube portion and outlet tube portion wherein separate halves of the tubular member are molded in a pair of molding dies, the molded separate halves in the molding dies being brought into abutment with each other, a melted resin mass being filled into an interior passage defined along a peripheral edge of the abutted portions to thereby join the separate halves, the method comprising:using a pair of molding dies for die rotary injection molding adapted to be opened and closed relative to each other and rotatable in relation to each other over a predetermined angular range, the molding dies having a molding section consisting of at least one male molding portion and two female molding portions in a repetitive sequence of male/female/female in the direction of rotation for each rotational run over the predetermined angular range, the molding dies further having a slide core adapted to be fitted to a tube end portion of one of the inlet and outlet tube portions and slidable in a direction different from the direction in which die opening and closing is made; and carrying out:the step of core insertion for inserting the slide core into a molding portion of the molding die pair corresponding to the tube end portion of one of the inlet and outlet tube portions;the step of die clamping for closing and clamping the molding die pair;the step of injection for injecting a melted resin mass into a molding cavity defined by closing the molding die pair;the step of die opening for opening the molding die pair;the step of core removal for removing the slide core from the tube end portion;the step of ejection for ejecting a molded tubular member from the molding die pair; andthe step of die rotation for rotating the dies over a predetermined angle,wherein each time when one rotational movement of the molding die pair is made, a primary molding operation for molding separate halves through a combination of the male molding portion and one female molding portion, and a secondary molding operation for joining a pair of separate halves through a combination of the female molding portions are performed so that a finished tubular member will be obtained for each rotational movement of the molding dies.