Patent ID: 7531119
Filing Date: 2009-05-12
Classification: B29C,B29L,F16D

Abstract:
1. A method of manufacturing a boot for a constant-velocity universal joint, the boot having a plurality of thick portions adapted to concave portions of a casing of a tripod joint and formed to protrude toward a center direction and a plurality of thin portions formed between adjacent thick portions, the method comprising the steps of: preparing a primary molded member having a large-diameter side end portion, a small-diameter side end portion, a bellows portion formed between the large-diameter side end portion and the small-diameter side end portion and constituted of repeatedly arranged large-diameter portions and small-diameter portions, and a tapered portion formed between the large-diameter side end portion and the small-diameter portion in a vicinity of the large-diameter side end portion in the bellows portion, holding the small-diameter portion in the vicinity of the large-diameter side end portion between an inner peripheral surface of a mold disposed in an outer peripheral side of the primary molded member and an outer peripheral surface of a core mold disposed in the large-diameter side end portion, forming a secondary molding space constituted of a thick portion molding space molding the thick portion and a thin portion molding space molding the thin portion between a large-diameter side end portion inner peripheral surface of the primary molded member and a core mold outer peripheral surface, injecting a molten material to the secondary molding space; and molding a secondary molded portion constituting the plural thick portions and the plural thin portions on the large-diameter side end portion of the primary molded member, the step of injecting the molten material to the secondary molded portion including the steps of: