| 摘要 |
PURPOSE:To obtain the cost down preventing a belt from its slip by forming irregularity on surface of many grooves, formed by rolling, in a direction not in parallel with the direction of these grooves, when a pulley is manufactured by forging. CONSTITUTION:A column-shaped material 4 is forged and molded into shapes 5a, 5b before grooving work. A recessed part 6 is formed in a large quantity along the periphery in parallel with the axial direction of a pulley 7, that is, in a direction crossing at a right angle with the direction of many grooves. Thereafter forming a grooved part 7a by rolling, the pulley 7, having the many grooves, is obtained. The pulley 7 forms its grooved part 7a into an irregular surface. Thus increasing a coefficient of friction of the surface in the grooved part 7a, a bridge mounting poly V belt is prevented from slipping. |
