Sheet-met′al punch.
A machine for perforating sheet-metal. In Seifurth's punchingma-chine the die a, fixed in the block b by a screw, is caused to reciprocate by means of a pitman c and eccentric d. The punch n is stationary and adjustable in hight by a screw f beneath. The cam g and rod h operate the lifter i, which has two prongs, one on each side of the punch-holder k; these rise after the blow is given, and immediately fall back, allowing the workman time to adjust the sheet of metal before the die returns; the die and block have openings l through which the punchings escape. A gage m, secured by clamps o to the sheet, serves to guide the punch; the holes in these are larger than the diameter of the face of the punch n, which has a convex shoulder; this arrangement permits holes of various shapes to be punched without using special gages. By employing different gages any description of holes may also be punched without the necessity of previously laying off and marking their positions. By varying the hight of the punch, impressions of any desired depth may be made in the metal. See also punch. |
| Sheet-metal scourer. |
