JPS6471716A - Two-material molding - Google Patents

Abstract

PURPOSE:To permit a second molded form to be molded with a predetermined thickness, by a method wherein a plate-type projection, positioned between a second molded form and a projected part from the end rim of a first molded form, is engaged with a recessed groove at the end rim of the first molded form when injected material flows from one surface of the first molded form into the other surface of the same through penetrating boles. CONSTITUTION:The main body 1 of the suction port of an electric cleaner is constituted of a lower case 2 and a plate-type first molded form or an upper case 3, which are combined through a second molded form or a bumper 4. Upon molding, molten resin, injected from a gate 44 into a cavity 43, flows from a part, which becomes a plate piece 36 of the bumper 4, into another part, which becomes the inside bumber part 32 of the upper case 3, and, further, flows into the other part, which becomes the outside bumper the part 31 of the upper case 3, through a notch 24 and penetrating holes 25. In this case, the plate-type projection 45 of a core 42, separating the part, which becomes the plate piece 36 of the bumper 4 and is faced to the gate 44, from the other part, which becomes a projected rim 35, is engaged with a recessed groove 28 before the lower rim of the upper case 3, therefore, the deformation of the upper case 3 from the inner surface side toward the outer surface side thereof may be prevented against an injection pressure from the gate 44.