| 摘要 |
PURPOSE:To eliminate the unbalance of formation regardlessly of the presence of a wall-thickness deviation in a hollow blank material, by floatably holding at least one of a pump engaging with the inner peripheral surface of a hollow blank material or a die engaging with the outer surface thereof, in the direction intersecting perpendicularly to the pressing direction. CONSTITUTION:A hollow material W is first cut to a proper length and is positioned at its lower end after inserting it to a punch 11. Next, an ejector 18 is lowered to insert a projecting part 11a of the punch 11 into a fitting hole 18a of the ejector 18. Thereafter the material W is gradually drawn from its front end by a die 15 by lowering an upper die 2. At that time, because of the presence of a wall-thickness deviation in the material W, the punch 11 is laterally slidden on a lower die 1 while deforming an elastic member 14 to follow up the wall-thickness deviation and is balanced, and the ejector 18 is also moved laterally while following up the movement of punch 11. That is, the material is successively processed without entirely causing an unreasonable force acting on the punch 11 and the die 15. |
