| 摘要 |
PURPOSE:To form a projection efficiently and surely and prevent wear of forming tools by providing a rolling contact roller eccentrically at the tip of a tool that confronts a tool that pushed out to the position of forming of a bottomed cylindrical projection made of metallic sheet. CONSTITUTION:For instance, to form a bottomed cylindrical projection 23 on the side of the body of a bayonet type bottomed cylindrical base, a jig 22 is lowered, a punch holder 3 is raised and inserted into the body 1, and the bottom face 2 is clipped. A die 17 is moved to the body 1 while rotating it at high speed in axial direction, and the peripheral part 21 of an eccentrically positioned roller 19 is brought into contact with the outer face of planned forming. As the roller 19 rotates around a punch head 8 while rotating on its own axis, the part clipped by the roller 19 of planned part and a punch guide 11 are heated in a short time by frictional heat caused by rolling contact of the roller 19. When the die 17 is advanced further, the head 8 is protruded from a through-hole 14, and the planned part is plastic deformed to a shape corresponding to the head 8, and a pin 23 is formed. |
