METHOD AND DEVICE FOR PRODUCING INTERNAL RELIEF BEARING

PROBLEM TO BE SOLVED: To control the oil hole state in the inside diameter face of an internal relief bearing in a sizing stage without requiring the addition of an another stage. SOLUTION: Raw material powder is compacted, so as to form a green compact. The green compact is sintered, so as to form a sintered compact. Then, the sintered compact is subjected to sizing treatment. In this way, an internal relief bearing having relatively small-diameter parts on both the sides in the axial direction and a relatively large-diameter part on the central part in the axial direction is produced. Regarding the sizing treatment for the sintered compact formed into a cylindrical shape, in a state where a core rod is inserted into the sintered compact, compression molding treatment is performed. As the compressed state is retained, the core rod in which a projecting part or a recessed part is formed at the tip part is drawn from the sintered compact, thus it acts so as to slide the inner circumferential face, and an oil hole state is changed. COPYRIGHT: (C)2007,JPO&INPIT