| 摘要 |
PURPOSE:To execute all forming processes only by press work by a method wherein concavo-convexes for prevention of disengagement of a packing, etc. are formed by press work on a blank which is in the state of a flat plate before forming. CONSTITUTION:The outline of a blank 1 having a necessary volume for a back in died out (a) 1, and a groove 2 is formed (b) by press work on the blank 1 which is in the state of a plane. At this time, the groove 2 is preferably formed to be opened at a half angle of 10-30 deg.C on the surface side of a plate as shown in the figure (e). Subsequently, a cup 3 is formed (c) by drawing, and further the back 4 is formed (d) in a complete shape by forming. The cost for manufacturing the case can be reduced by applying the pressing to all the processes in this way. |
