METHOD FOR MANUFACTURING A BOOT OF A CONSTANT VELOCITY JOINT, A MANUFACTURING DEVICE THEREBY, AND THE CONSTANT VELOCITY JOINT BOOT WITH A THICK PART FORMED IN THE END OF A LARGE BORE

摘要

PURPOSE: A manufacturing method of a boot for a constant velocity joint, a manufacturing device thereby and the constant velocity joint boot are provided to prevent leak of material during the secondary forming process by forming the secondary molding part with the thick part in the inner periphery of the large bore formed by the primary forming process. CONSTITUTION: A secondary forming space is produced between the inner periphery of an end(3) of a large bore of the first formed product and the outer periphery of a core mold, and molten material is injected to the secondary forming space to form the secondary forming portion. A tapered surface(27) is extended from a small bore part(7b) near the end of the large bore to the large bore end by applying pressure of molten material injection-molded in the secondary forming space. The tapered surface is extended to the small bore part, and the small bore part between the inner periphery of a partition mold(51) and the outer periphery of the core mold is pressed and contacted to the outer periphery of the core mold.