| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an apparatus for manufacturing an unequal thickness rim that can shorten a working time while surely preventing a hollow cylindrical material ring from moving along an axis direction during plastic working. <P>SOLUTION: The respective outer peripheral surfaces on the insertion tip side of a first mandrel 1 and a second mandrel 2 are formed with annular recesses A comprising a first annular recess 1A and a second annular recess 2A reduced in diameter to the inner diameter side. In a position corresponding to the annular recesses A in the direction of an axis X1 of the rotated hollow cylindrical material ring W, a control means moves a pressing roller 3A from the outer diameter side to the inner diameter side to press the outer peripheral surface Ws of the hollow cylindrical material ring W so that a pressed portion Wp is plastically deformed into shape conformed to the annular recesses A and placed in a held state between the pressing roller 3A and the annular recesses A. The control means moves spinning rollers 3B from the outer diameter side to the inner diameter side while maintaining the held state, and moves the spinning rollers 3B in a direction to approach the end from the position corresponding to the annular recesses A in the direction of the axis X1 of the hollow cylindrical material ring W while pressing the outer peripheral surface Ws of the hollow cylindrical material ring W, thus adjusting the thickness of the hollow cylindrical material ring W of straight pipe shape. <P>COPYRIGHT: (C)2013,JPO&INPIT |
