| 摘要 |
PURPOSE:To equalize a thickness of a multi-grooved V-pulley, and to obtain a multi-grooved V-pulley made of sheet metal without strength deterioration by forming preliminarily a lug part and the first groove in a curved part formed on the peripheral wall of a cup-shaped stock, also making said wall thick, and subsequently, multi-forming a V-shaped groove. CONSTITUTION:A curved part 11a is formed on the peripheral wall of a cupshaped stock 1 by using a plunger punch, etc. It is inserted and held, and fixed in a rotary inner die, compressed by using an auxiliary forming roller, a lug part 13 and the first groove 12 are formed preliminarily, and the peripheral wall is made thick 14. It is placed in other rotary inner die, and plural V-shaped grooves 2 holding a prescribed interval are formed in a multiple shape by using a V-groove forming roller. Also, plural V-shaped grooves 2 are rolled deeply by using a finishing roller in other rotary inner die, and a multi-grooved V-groove 3 of a prescribed shape having a projecting part is formed. According to this method, a multi-grooved V-pulley made of sheet metal can be manufactured in a high mass-production. |
