MOLDING METHOD OF OPTICAL PART, MOLDER USING HOT-RUNNER TYPE MOLD AND OPTICAL PART

摘要

PROBLEM TO BE SOLVED: To prevent members, ejector pins and a lens from being damaged by a method wherein an optical part is injection-molded in a hot runner type mold and, after being cooled down, ejected from the mold with ejector pins and unloaded by pinching the side surfaces of the part with pinching members, which actuate through loci not intersecting with the ejecting loci of the ejector pins. ;SOLUTION: An object lens 1 is molded by directing its flat lens surface to a fixed mold side and its concave lens surface to a movable mold side under the condition that the flat lens surface acts as a parting line. A molding is formed between the fixed mold and the movable mold by pouring a molten resin through the gate 1d of a nozzle and, after being cooled, the movable mold is separated from the fixed mold, four corners of small side surfaces at the periphery of the concave lens surface of the object lens 1 are ejected with four ejector pins 71 from the movable mold side direction. By pinching the side faces of the object lens 1 with the extended arm parts, at the tip of each of which a pinching member 12 is provided, of an unloading device, the molding is removed from the side of the movable mold. Since the ejector pins 71 and the pinching members 12 do not about against each other, no breakage occurs in the pins and members and the lens surfaces can be prevented from being damaged.;COPYRIGHT: (C)1999,JPO