Patent ID: 8402658
Filing Date: 2013-03-26
Classification: B21K,Y10T

Abstract:
1. A method of manufacturing a compressor pulley which comprises a plate-shaped base portion, and an internal ring portion and an external ring portion that are each integrally formed with the base portion and protrude in a length direction of the compressor pulley, said method comprising: heating a metallic material to at least a predetermined temperature; hot-forging the metallic material into a pulley shape having the base portion, the internal ring portion and the external ring portion; piercing a center portion of the metallic material to form a through-hole at a connecting portion connecting with an inner surface of the internal ring portion; cooling the heated metallic material to a room temperature; grinding inner and outer surfaces of the cooled metallic material; partially cold-forging the base portion at the room temperature; forming slots at the base portion; and performing groove working and grinding on a surface of the pulley-shaped metallic material, wherein a thickness of a bridge portion that is formed between the slots after the grinding is larger than a standard thickness of the base portion, and the partial cold-forging is performed only on the bridge portion that has the thickness larger than the standard thickness of the base portion.