| 摘要 |
PURPOSE:To elevate the intensity of a hook by performing the bend work of a hook shape with providing a rooler metal die together with a pressuer metal die, then, by performing a press work of the hook part to approx. trapezoidal shape. CONSTITUTION:A pressing die 6 is provided in opposition to the vertical wall 5 of a die device E and the roller metal die 7 which is movable to the direction of the pressing metal die 6 is arranged on the side of the vertical wall 5a. Bending work of hook shape is performed on a base material 1 with driving the roller die 7 so as to perform the movement in the peripheral direction as well as moving the pressing die 6 to the direction of the vertical wall 5a. The press work of trapezoidal shape is then performed with a press forming machine on the part where the load of the main body A of the hook is placed on. With this cold work, the intensity property of a tensile strength, etc. is elevated. |
