| 摘要 |
PURPOSE:To machine a distance between both centers of a work to a fixed length even if the work is provided with unevenness in its length while machine at least one of the center holes in a fixed depth. CONSTITUTION:A work W is movably supported in the axial direction between a primary side punch 1 and a secondary side punch 2. Under this condition, an oil hydraulic cylinder is operated to adapt the punch 1 to an end face S1 of the work W, if the hydraulic cylinder is further operated, the face S1 is adapted to a stopper face 12 of an aligning ring 13 to form a center hole of required size l1 to the face S1. An advance limit position of the punch 2 is determined by a mechanical stopper, and advancing motion of the punch 2 is continued by a distance l2 for a length L of the work W to form a center hole of required size to a face S2, in this way, unevenness of the distance l2 between the center holes can be reduced. |
