PURPOSE: To draw into sufficient depth without reducing the thickness of the middle part, by preliminarily forming the part to be drawn of specified width and height between the draw forming corresponding parts to which a blank adjoins, placing the blank on the die, and pushing in the punches in the draw forming corresponding parts to supply the material from the part to be drawn into the middle part.
CONSTITUTION: A blank 19 preliminarily bent and formed to width l and height h is placed on a die 10, and is held by a holder 16. At this time, draw forming corresponding parts 20A, 20B correspond to pressure chambers 12A, 12B and punches 15A, 15B. A middle lower position holder 11 is pressed into the part to be drawn 21, and a middle upper position holder 17 is contacting with the upper surface of the part to be drawn 21. An elevating body 14 is lowered, and the both punches are lowered to draw deeply. When drawing, the material is supplied from the part to be drawn 21 into the middle part. As the drawing further continues, the both holders 11, 17 also move, so that crease is not caused in the middle part. When drawing process is over, the part to be drawn 21 is pulled into the middle part of the product to be flush with the original blank surface, so that a product 23 having two drawn parts 22 may be obtained.
SAKAI YOSHIHITO
NISHIKAWA TOSHIHARU
| JPS5170178A | 1976-06-17 |