MANUFACTURING METHOD OF A WORKPIECE HAVING AN UNDERCUT AND A CORE REMOVING DEVICE FOR PRODUCING INTEGRALLY THE WORKPIECE WITHOUT WELDING, SCREW-COMBINATION, OR COMPLEX POST-PROCESS

• Main Authors: KIM, JONG HA, NISHIHARA, FUMIO
• Format: Patent
• Language: English; Korean
• Published: 27.01.2005
• Edition: 7
• Subjects: AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; PERFORMING OPERATIONS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDEDFOR; SHAPING OR JOINING OF PLASTICS; TECHNICAL SUBJECTS COVERED BY FORMER USPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ARTCOLLECTIONS [XRACs] AND DIGESTS; TRANSPORTING; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL

PURPOSE: A manufacturing method of a workpiece having an undercut and a core removing device are provided to increase the freedom degree of a design by producing integrally components by using a core and to widen an industrial application filed. CONSTITUTION: A manufacturing method of a workpiece having an undercut is composed of steps for positioning an undercut forming core in a mold; producing a preliminary workpiece(100) by filling the mold with a molding mixture; and removing the core from the preliminary workpiece. The core is made from thermoplastic resin. The core is eliminated by immersing the preliminary workpiece in an organic solvent(222) or heating the preliminary workpiece. The preliminary workpiece is made by an injection molding method. The molding mixture contains metal powders and a bonding agent. The bonding agent is removed by sintering the workpiece in a sintering furnace.