US2212886A

US2212886A - Cutting tool

Info

Publication number: US2212886A
Application number: US216896A
Authority: US
Inventors: Fred F Ruland
Original assignee: Individual
Current assignee: Individual
Priority date: 1938-07-01
Filing date: 1938-07-01
Publication date: 1940-08-27
Anticipated expiration: 1957-08-27

Description

Patented Aug. 27, 1940 UNITED STATES PATENT OFFICE 7 Claims.

This invention relates to a cutting tool consisting of a metal punch and die.

One object of my invention is to provide a tool to punch holes in sheet metal by hand which is simpler to use and more certain in attaining desired results than those heretofore known. I am aware that punches and dies to make holes in sheet metal by hand are well known; but they are in several respects unsatisfactory, and it has been my principal object to substantially improve them by having only-two separate parts, and soconstructing these parts that they interfit and operate in such a manner that the desired holes will correctly be cut out, even though the initial positioning of the punch and die together is not done accurately or the hammering done unevenly.

Another object is to provide such a tool that will shrink or lessen the width of the piece it cuts out so that it will not bind when it is being removed. Still another object is to accomplish the foregoing and other objects with a tool of such construction that is economical and simple to manufacture, and practically certain to attain the desired results even when faultily used.

The foregoing and other objects which will appear as the nature of the invention is better understood, may be accomplished by a construction, combination and arrangement of parts such as is disclosed by the drawing and specification. The nature of the invention is such as to render it susceptible to various changes and modifica tions, and, therefore, I am not to be limited'to said disclosures; but am entitled to all such changes therefrom as fall within the scope of my claims.

In the drawing:

Figure 1 is a front elevational view of my punch and die separated.

Figure 2 is a plan view of my die.

Figure 3 is a plan view, broken away, showing a piece of metal between my punch and die, ready to have a hole cut in it.

Figure 4 is a front elevational view, partly in section, showing a piece of metal resting on top of the die with the punch directly overhead ready to be placed in position with respect to said die to cut a hole in said piece of metal.

Figure 5 is a sectional view, broken away, showing the punch and die and a piece of metal with a piece cut out of it, leaving a hole, at the completion of the cutting operation.

My punch P consists of a main body portion Ill preferably having a fiat level bottom surface extending from the outer edge inwardly a short distance. A pilot or centering pin II is fixed in said body portion l and projects beyond the end a short distance, terminating in a tapered portion l2. A recess I3 is formed in the lower portion of said body l0, extending inwardly and upwardly into the interior and being preferably of greater depth than the die recess l6 later described.

My die consists of a main body I4 at the top of which is formed a top face outer rim l5,'having inner and outer sides which extend straight downwardly therefrom. Extending inwardly 10 from the inner edge of said top face outer rim I5 is a bore or recess l6, adapted to receive the cutting or end portion of said punch P, the bottom of which recess slants downwardly towards the outside as at H, terminating at its outside and is lowest point, as shown in Figures 4 and 5 of the drawing. Surrounding a hole formed in said body M at the center thereof is a boss or raised portion l8 which preferably'is substantially level with said top face outer rim l5. Said pilot pin 20 ll fits into said hole 20 and thereby assists in accurately positioning the punch P in said die D. Said boss or raised portion l8' makes it possible to use a short pilot pin I l which need extend beyond the body of said punch P only a short distance, this extending portion being the tapered part l2 which is thereby enabled to more easily enter said hole 20 should it be mistakenly positioned a little off to one side of said hole 20. Because this extending part of the said pilot pin II is so short and tapered it is unlikely to be broken or bent should the punch P be struck unevenly or not enter the recess IS in said die in the position it should during the cutting operation.

As will be noted in Figure 5 of the drawing said boss l8 extends into said punch recess l3 during the cutting operation which forms the hole 2|, and part of the severed part 22 of the metal sheet M also extends therein because it bends upwardly, which shrinks it in width. As shown in Figure 3 of the drawing, before the punching operation is begun, it is desirable to drill or otherwise make a small hole 23 in the piece of metal M through which said pilot pin ll may extend and enter said die hole 20.

My tool is used by laying a piece of metal M over the top of said die D with the hole-23, that is previously made in said piece of metal M, directly over the hole 20 in said die D, and inserting the said pilot pin l I through said hole 23 and into said die hole 20. Hammering on said punch P cuts out a hole 2|, the middle portion of the out part 22 being bent so that it slants upwardly towards the center thereof, thereby shrinking its 5 diameter so that it will be slightly smaller than said hole 2| and not bind when being removed back through the hole punched.

By forming said die recess l6 so that its lowest point is outermost, the outside or shearing edge of said punch P will not touch said die at this point, as illustrated in Figure of the drawing, thereby avoiding any likelihood of damaging my tool or locking said punch and severed piece of metal 22 in the said recess 16.

What I claim is:

l. A cutting tool comprising a punch having a recess and having a flat bottom surface of narrow extent adlacent the outer edge of said punch and outside of said recess, and having a pilot pin extending beyond the end thereof, and a die having a hole therein adapted to receive said pilot pin end, and having a recess outside of said hole into which a portion of said punch may enter during the cutting operation, said die having a boss portion outside of said hole, said recess commencing at the termination of said boss portion and slanting downwardly and outwardly evenly to its outermost point.

2. A cutting tool comprising a punch having a flat bottom surface commencing at and extending inwardly from the outside edge and having a pilot pin extending beyond the end of said punch, and a die having a hole therein adapted to receive said pilot pin end, and having a recess outside of said hole into which a portion of said punch may enter during the cutting operation, said die having a boss portion outside of said hole, said'recess commencing outside of said boss portion and extending diagonally downwardly and outwardly.

3. A cutting tool comprising a punch having a pilot pin extending beyond the end thereof and having a recess therein extending inwardly from said end, a die having a hole therein adapted to receive said pilot pin end, and having a boss portion outside of said hole and a recess outside of said boss portion into which a portion of said punch may enter during the cutting operation, the maximum depth of said punch recess being greater than the maximum depth of said die recess.

4. A cutting tool comprising a punch having a pilot pin embodying a straight shank portion and a reduced end portion extending beyond the end thereof and having a recess therein extending inwardly from said end, the distance said straight shank. portion extends beyond said end being less than the length of said reduced end portion, and a die having a hole therein adapted to receive said pilot pin end, and having a boss portion outside of said hole and a recess outside of said boss portion into which a portion of said punch may enter during the cutting operation, the distance said pilot pin straight outside of said boss portion into which a portion.

of said punch may enter during the cutting operation, the outside end of said pilot pin being tapered, said tapered portion commencing substantially opposite the deepest point of said die recess when said punch is in cutting position in said die.

6. A cutting tool comprising a punch and a die, said punch; having a flat, bottom surface extending inwardly from its outside edge and a recess extending from the inner edge of said surface interiorly into the body of said punch, a pilot pin fixed in the body of said punch having a tapering outer end which extends beyond said surface outwardly, said die having a hole therein adapted to receive said pilot pin, a boss portion adjacent to and surrounding said hole, a recess extending from and around said boss portion into the interior of said die adapted to receive the whole end portion of said punch during the cutting operation, the bottom of said recess slanting downwardly and outwardly in the same angular direction continuously to its terminating point, and a top face outer rim extending inwardly from the outside edge of said die the top surface of which is in a horizontal plane and substantially even with the top surface of said boss portion.

'7. A cutting tool comprising a punch and 9. 40

die, said punch having a flat, bottom surface extending inwardly from its outside edge and a recess extending from the inner edge of said surface interiorly into the .body of said punch, a pilot pin mounted in said punch having a straight shank portion that extends beyond the end of said punch a distance less than twice the maximum depth of said punch recess and havin a tapering outer end which extends beyond said shank portion, said die having a hole therein adapted to receive said pilot pin, a boss portion adjacent to and surrounding said hole, a recess extending from and around said boss portion into the interior of said die adapted to receive the whole end portion of said punch during the cutting operation, and a top face outer rim extending inwardly from the outside edge of said die having a top surface substantially level with the top surface of said boss portion.

FRED F. RULAND.