| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a sheet metal punching device, which can secure the strength of a projection without causing deterioration of durability, which can secure restriction of movement of the sheet metal by the projection even after forming a breakthrough hole and can position the sheet metal, and also which can prevent the diameter expansion of the breakthrough hole by a punch body and can reliably break the sheet metal by tensile in circumference of an annular edge of a cylindrical inner surface of a die where the one end of a die hole is defined in corporation with the punch body, thereby forming a through hole to the sheet metal. <P>SOLUTION: The sheet metal punching device 1 includes an upper die holder 2 lifted up and down by a hydraulic ram etc., a pressing plate 3 fixed to the upper die holder 2, a pressing pad 5 hung on the upper die holder 2 through an elastic member 4, a punch holder 7 fixed to the pressing pad 5, a lower die 9 where the sheet metal 8 to be punched is placed, and the die 10 embedded in the lower die 9. <P>COPYRIGHT: (C)2013,JPO&INPIT</p> |
