| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a knockout punch to improve the present difficulty in matching the punch, for example, in checking a matching mark. <P>SOLUTION: This knockout punch is provided with one member. This member on the knockout punch locates the punch assembly in a pilot hole when the knockout punch and the die are drawn together by a draw stud to make a hole in a workpiece. In three embodiments of the present invention, the member is formed integrally with the punch, and extends from the punch proximate to a bore in the punch. This bore is used to connect the punch to the draw stud. In another embodiment of the present invention, the member is provided as an insert which is connected to the punch within a counter bore. The punch is also provided with a pair of piercing portions for piercing through the workpiece after the member has centered the punch assembly with the pilot hole and a pair of cutting portions for shearing the workpiece after the piercing portions have pierced the workpiece. <P>COPYRIGHT: (C)2003,JPO</p> |
