METHOD FOR MACHINING RECESS OF HEAD REST STAY

摘要

PROBLEM TO BE SOLVED: To provide a simple method for machining the sharp recess of head rest stay at a low cost. SOLUTION: A method is presented for machining a recess 2 which is prepared in the stay 32 part of a head rest stay 3 made of a pipe material. A punch 4 is rotated and abutted against the stay part 32 with pressure for preliminary forming of the recess 2, and then, the recess 2 is formed by press working using a press punch 8.