TWIST WORKING METHOD OF METAL USING ROTARY DIE

摘要

PURPOSE:To obtain a twisted plate having an optional twist angle from a flat plate with decreased loss of force by stacking dies which have working holes and are mutually rotatable into plural stages, inserting a member to be worked into the working holes and rotating respectively the dies. CONSTITUTION:The top end of the flat plate which is inserted in the dies comes to the position (a) and the bottom end to the position (b). The die A and the die B1 do not rotate each other but the die Bn and the die C are rotatable like the dies B with each other. The flat plate which is inserted into such dies is directly heated by high-frequency induction of a high-frequency coil 9. The dies rotate successively when the die A is rotated clockwise when viewed from the upper part in the axial direction in this state and rotate by (n+1)a deg. between the die B1 and the die C. (a deg. is the rotating angle of the two adjacent dies with each other). The flat plate is consequently twisted by (n+1)a deg. at the top and bottom ends. The twisted plate is thus worked from the flat plate.