Method and apparatus for press forming sheet material

Abstract

[Problem to be Solved] An object of the present invention is to obtain a component, such as an end plate of a silencer by one cycle of pressing operation for a sheet material. [Solution] A press forming apparatus comprises an upper die 10 provided with an upper drawing die 13, a punch 12, an upper movable blank holder 14, and a trimming member 15 and a lower die 20 provided with a lower drawing die 23, a die 22, an outer periphery drawing die 24, and a lower movable blank holder 25. The upper die is lowered with respect to the lower die, and the outer periphery portion of a blank B is held by the trimming member and the upper blank holder. Then, the central portion of the blank is drawn by the upper and lower drawing dies. Next, the outer periphery portion of the blank is trimmed by the trimming member and the outer periphery drawing die, and then drawing of the outer periphery portion of the blank is started by the upper drawing die and the outer periphery drawing die. Next, the blank is pierced by the punch and the die, and burring around the pierced hole is started. Next, the outermost periphery portion of the blank is bent by the trimming member and the outer periphery drawing die, thereby obtaining an end plate.

Dependencies are inferred from the claim text.