| 摘要 |
<p>A flat metal piece is deep drawn to form a cup constituted by a base and a hollow cylindrical side wall perpendicular thereto; the cup wall is thickened by cold working by subjecting the wall to the action of a press all around its profile, the thickening being completely finished by this pressing operation; thereafter, the pulley is shaped by the action of a transverse roller 7 which flattens the wall in the direction towards the pulley axis. The side wall is grooved-in by the action of a multiple circular thread type roller 10, so that this wall can receive a corresponding poly-V belt, such that in this rolling operation, the metal portion forming the crests comes from the metal displaced in the forming of the grooves. whereby there is no loss of metal having regard to the prior thickening of the cup wall. <IMAGE></p> |
