US939324A - Metal-punch. - Google Patents

Description

W. G. ROBINSON.

METAL PUNCH.

4 APPLICATION FILED MAY 29' 1909.

939,324 I Y I Patented Nov. 9, 1909.

WILLIAM G. ROBINSON, OF PITTSBURG, PENNSYLVANIA.

METAL-PUNCH.

Specification of Letters Patent.

Patented Nov. 9, 1909.

Application filed May 29, 1909. Serial No. 499,227.

To all whom it may concern:

Be it known that I, WILLIAM C. RoBINsoN, residing at Pittsburg, in the county of Allegheny and State of Pennsylvania,a citizen of the United States, have invented or discovered certain new and useful Improvements in Metal-Punches, of which improvements the following is a specification.

In attaching metal strips, plates, etc., to a supporting structure by nails or screws, it is frequently desirable that a counter sink should be provided for the head of the screw or nail. Unless the nails or screws'are so spaced as to render it possible to do the work in a shop, it is necessary for the workman to have not only a drill for making the holes but also a tool for making the counter sink, and these tools must be changed from the operating handle back and forth for every hole.

The object of the invention described herein is to provide a punching device so constructed that the hole and counter sink may be formed by one movement of the tool, which can be operated by a blow of the hammer.

The invention is hereinafter more fully described and claimed.

In the accompanying drawings forming a part of this specification is shown a sectional elevation of my improved punching device showing a strip in position to be operated on.

My improved tool consists of a heavy base 1 adapted to be secured by screws or bolts on any suitable foundation. This base is provided with upwardly projecting standard 2 provided at or near its upper end with an overhanging projection 3 having an opening therethrough adapting the same to act as a guide socket for the punching tool 4. This tool consists of a steel rod of a uniform diameter, except at its lower end, where it is reduced to form a punch 5. The

' displacement o shoulder 6 resulting from the reduction of the end of the rod in forming the punch portion 5, is beveled or inclined as shown, such inclination extending from the punch outward and upward. In the base plate 1 is formed an opening 7 slightly larger than the punch for the reception of the latter, and the walls of this opening at the upper end thereof are given a bevel or inclination as shown at 8 similar to that of the bevel of the shoulder 6. The rod is normally held in raised position by means of a spring 9 interposed between the upper end of the guide socket and a projection on the rod which may be formed by transverse pin 10.

In using this tool the metal strip, such for example as the case piece of a metal molding is placed on the supporting block with the point where the hole is to be formed in line with the punch and the hole in the block. The operator strikes the upper end of the rod a blow forcing the punch through the strip and also forcing the beveled shoulder down so as to produce a bevel or counter sink at the edges of the hole in the strip. The bevel at the upper end of the hole in the sup orting block permits of the f the metal necessary to the formation of the counter-sink in the strip.

I claim herein as my invention:

A hand operative punching tool having in combination a bar having one end reduced to form a perforating point and having a beveled or inclined shoulder at the base of said point and an anvil block having an opening therein for the reception of the point the end wall of the opening being beveled or outwardly inclined.

In testimony whereof, I have hereunto set my hand.

WILLIAM C. ROBINSON. Witnesses:

FRIEDA E. WOLFE, CHARLES BARNETT.

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