Patent ID: 7534382

Claim:
An insert injection molding method in which an insert having an angled portion formed by first and second plane portions thereof intersecting and integral with each other is overmolded by molding material at outer peripheral sides of the first and second plane portions so that said insert and the molding material are integrally formed with each other, the insert injection molding method comprising the steps of: preparing said insert and a jig comprising a core insertable into and drawable out of said insert and an outwardly pressing member insertable into and drawable out of said core, said core comprising a plurality of core members with a plane surface, said plurality of core members including first and second core members divided at the angled portion of said insert when said core members are built according to said insert in advance of a molten molding material injection into a mold; inserting said core into said insert so that the plane surfaces of said first and second core members respectively face to inner sides of the first and second plane portions of said insert; inserting and locating said insert with said core into the mold; inserting the outwardly pressing member into said core to press said first and second core members outwardly and bring the plane portions of said first and second core members in contact with the inner sides of the first and second plane portions of said insert respectively; injecting the molten molding material under pressure into a cavity of the mold in which said insert with the core and the outwardly pressing member is located; cooling the molten molding material in the mold to be a molded part; drawing said outwardly pressing member out of said core; drawing said core out of the mold; and removing the molded part from the mold.