| 摘要 |
PURPOSE:To drill only the first sheet of two sheets of steel plates, in which a spot welded part is required to be stripped, by a drill and strip the spot welded part without drilling a hole in the second sheet. CONSTITUTION:A drilling depth can be correctly determined by a distance between the left end face of a flange 3e of a rotary shaft 3 and the right end face of a cylindrical body 50. Air is conducted to rotate an air motor 4, then an end mill 48 is rotated to start drilling work to an exfoliated plate held by the end mill 48. However, a sliding distance of the shaft 3 is specified by the distance between the flange 3e and the body 50 as described in the above, and the end mill 48 is never advanced exceeding a thickness of the outside steel plate to be exfoliated. |
