US1812350A - Punching or cutting pliers - Google Patents

Description

June 30, 1931, Q F D LlNGWOQD 1,812,350

PUNCHING OR CUTTING PLIERS Filed Oct. 25, 1930 F011;; wow.

Patented June 30, 1931 UNITED, STATES PATENT OFFICE FREDERICK DONALD LINGWOOID, OF LONDON, ENGLAND, ASSIGNOR TO MANUFAX LIMITED, OF LONDON, ENGLAND, A COMPANY OF GREAT BRITAIN PUNCHING OR CUTTING PLIERS Application filed October 25, 1930, Serial No. 491,258, and in Great Britain November 8, 1929.

This invention relates to punching or cutting pliers or gimpers for use in cutting sheet material and has for its object to provide a convenient form of hand tool by which sheet material can be cut without causing its distortion and without forming aburr.

A tool according to the invention comprises a slotted jaw forming a work-supporting table or anvil adapted to cooperate with a cutting aw which at each cutting operation removes a portion of sheet material of an area which does not exceed that of the jaw itself, the pivot by which the cutting jaw is connected to the anvil jaw being disposed wholly below the level of the work supporting anvil,

The surface of the anvil is inclined relatively to the arm on which it is formed and not only does the forward end of the anvil project beyond the forward edge of the cutter, but its sides extend rearwards on each side of the cutting arm.

Further, the neck of the cutter preferably is of such reduced cross-section that after a slot has been cut, the cutter can be turned in the slot so as to execute the next cut in any desired direction. If rectangular portions of sheet material are to be removed at each cut, the cutting jaw is of rectangular shape or if desired the head or nose of the 39 cutter may be of parabolic form thus enabling curved slots with substantially smooth edges to be cut of any radius greater than the smallest radius of the cutting jaw.

I The work-supporting anvil may be provided with a stop to limit the extent to which the sheet material can be inserted between the jaws and fixed or removable fences or stops may be provided to determine the rela t-ive position of successive cuts.

Various constructional forms according to the invention are illustrated in the accompanying drawings, in which I Figure 1 is a perspective View of one construction,

Figure 2 is a view showing how the construction shown in Figure 1 can be used,

Figure 3 is an enlarged plan view of the operative port-ion of an alternative construc- ,tion,

Figure 4 is a view showing how the alternative construction shown in Figure 3 can be used to cut out curved slots,

Figure 5 is a sectional side elevation of a modification applicable to either of the constructions shown in Figures 1 to 4L,

Figure 6 is a perspective view of a modified construction having movable side spacing fences or stops with one of these stops shown detached from the tool,

Figure 7 illustrates the manner in which the tool shown in Figure 6 can be employed to form a series of equally spaced tongues along the edge of a piece of sheet material,

Figure 8 is a side elevation of a further modified construction having movable side spacing fences, and

Figure 9 is a plan of the construction shown in Figure 8.

In the construction illustrated in Figures 1 and 2 the tool is adapted to remove a small rectangle of sheet metal at each cut and comprises two arms A, B, pivotally connected together at C. The arm A, which is of channel section, carries a jaw slotted at A and forming a work-supporting anvil having side portions A connected by an end portion A which closes the end of the slot A the pivot C being disposed wholly below the level of the actual work-supporting anvil. The surface of the anvil is inclined to the main portion of the arm A as shown so that when a cut is being made at some distance from the edge of a piece of sheet metal the arm A will lie wholly below the sheet metal so that the workers hand can grasp this arm without de fleeting the sheet metal or other work. The end of the arm 13 is formed as a projecting cutting head B which cooperates with the sides and end of the slot A in the work-supporting anvil to cut out a small rectangle of sheet metal. The cutting head B is connected to the arm by a narrow neck 13 of such dimensions that it can be rotated in a slot cut by the cutting head so that the next cut can be made in any desired direction as indicated in Figure 2. Thus the back of the neck B is cutaway or rounded as shown so that the largest cross-sectional dimension of this neck is smaller than the width of the slot cut by the cutting head. The depth of the cutting slot A may be of some other convenient head B measured in'a plane at right angles to that in which the cutting edges lie is, further, less than the width of the cut so that this head can readilybe inserted into a slot already cut.

The depth ofthe cut, i. e. the distance between the free end of the cutting head B and the edge of the work, islimited by the surface 13 so that the overhanging portion of the cutter BPcoincides with the dimensions of the piece ofsheet metal of maximum size which can be removed by a single out.

In the alternativeconstruction illustrated in Figures 3 and i the general arrangement is similar to that illustrated in Figure 1 except that the cutting head or nose B is formed with thecutting edges parabolic as shown, these edges cooperating with a similar parabolie sloth in the anvil jaw A Alternative'ly,'the cutting head or nose B and the curvedfform. /Vith this construction also the back of the neck-connecting the cutting head to the arm is rounded as shown at B so that thelargest cross-sectional dimension of "this neck is smaller than the width of the slot out, With this construction of cutting head it will be seen that curves of any radius larger than the minimum radius of the cutting edge can-be executed as indicated in Figure 4, these curves being smooth and not requiringfiling out. I

In the modification'illustrated in Figure 5 which may beapplied to the construction of Figures 1 and 201 that shown in Figures 3 i and 4, the anvil A on the anvil arm A is pro.-

vided with a step A which limits the extent to which the sheet material A can be inserted between thejawsjand hence the depth of the ,cut which canbemade at one cutting operation by'the cut-ting head B 7 7 In an alternative construction illustrated in Figure 6 the tool comprises: ajaw D constituting a work supporting anvil andhaving a'slot therein through'which passes a cutting j aw E pivoted to the anvil awat F, the cutting jaw E and the work-supportinganvil D with which the cutting edges cooperate being so formedrespectivelywith a slot E anda projectionl) that at each cutting operation they will remove a substantially U,-

shaped piece of sheet material so as to leave atongue' ofthe dimensions of. the projection DY. w 7 7 Pivoted at G? to each side ofthe anvil jaw is a movable side fence or stop G only one of whichis intended to be moved into its operativelposition at a time as shown in Figure 6, the other being rocked about its pivot so as to be in an inoperative position. In Figure 6Lone of thestops G is shown as removed from the anvil for the sake of clearness. The operative end G of each of these stops whenin its operative position rests on i the anvil D and is so disposed that if after a cutting operation the edge of the tongue which has thus been formed is placed against the stop, the adjacent cutting edge of the cutting jaw will just overlap the edge of the slot already cut whereby on the next cutting operation, in addition to forming a second tongue, the tool will complete the formation of the space between the two tongues as clearly shown in Figure 7. Further the width of each of the two portions 7 E of the cutter whichforms a side of the U is slightly greater than half the width of the tongue which is formed at each cut so that when used as above described to cut out two or more tongues with a gap between them this gap will be equal to or slightly greater than the width of each tongue. p i r The purpose of this is to enable a series of evenly spaced tongues to be formed on the edge of a piece of sheet material with spaces between them such that tongues similarly formed on a second piece of sheet material can be, brought into engagement with these spaces and the tongues on both pieces of sheet material then bent over so as to join the two pieces of sheet material together for example at right angles or at some other angle relatively to one another.

It will be seen that by employing one or other of the movable side fences or stops G a series of tongues can be formed in succession along the edge of a piece of sheet material, the first tongue being formed at either end of the series. a 7 iv In the modified construction shown in Figures 8 and 9 the tool comprises a porting arm H having a part H acting as a work-supporting anvil, and a cutting arm J pivoted thereto at K and having a cutting head J which, in the construction shown, is adapted to remove a rectangular piece of sheet material. Other forms of cutting head may, however, be employed. Rotatably mounted on the pivot K on each side of the work-supporting anvil H are two side fences or spacing stops L each provided'with an eX- tending lug L having a projection L formed on its inner face and adapted to cooperate with small recesses in the side of the anvil arm Hso as to hold thespacing stop L. either p in its operative position as shownin full lines in Figure 8 or in its inoperative position as shown in dotted lines in Figure 8. .In Figure 9 one of the spacing stops is shown in its operative position and the other in its inoperative position. 7

In operation, after the tool shown in Fig ures 8 and 9 has been used to cutone slot, it i the slot cut, as indicated. If desired, however, the laterally projecting part of the head may be omitted.

hat I claim as my invention and desire to secure by Letters Patent is 1. A tool for cutting sheet material including in combination two arms, a slotted jaw carried by one arm forming a work-supporting anvil,'a cutting jaw in the form of a head carried by the other arm and adapted to pass through the slot, a neck portion connecting the head to its arm and having its cross-sectional dimensions reduced so that the cutter can be turned in a slot already cut and the cut continued in any other desired direction, and a pivot connecting the arms disposed wholly below the work-supporting surface of the anvil.

2. A tool for cutting sheet material including in combination two arms, a slotted jaw carried by one of the arms and forming a work-supporting anvil, a cutting jaw in the form of a head carried by the other arm and adapted to pass through the slot, a neck portion connecting the head to its arm and having its cross-sectional dimensions reduced so that the cutter can be turned in a slot already cut and the cut continued in any other desired direction, and a pivot connecting the two arms disposed wholly below the level of the work-supporting anvil, the work-supporting surface of said anvil being inclined relatively to the arm which carries it and extending rearwardly on either side of the cutting jaw.

3. A tool for cutting sheet material including in combination two arms, a jaw carried by one arm forming a work-supporting anvil and having a curved slot therein, a cutting jaw in the form of a head carried by the other arm and curved to correspond to the slot in the anvil and adapted to cooperate therewith, a neck portion connecting the head of the cutting aw to its arm and having its cross-sectional dimensions reduced so that the cutter can be turned in a slot already cut to form a cut of any radius greater than the least radius of the cutter, and a pivot connecting the arms disposed wholly below the level of the work-supporting surface of the anvil. I

4. A tool for cutting sheet material including in combination two arms, a jaw carried by one of the arms forming a work-supporting anvil having a curved slot therein, a cutting jaw in the form of a head carried by the other arm and curved to correspond to the slot in the anvil so as to be capable of passing through the slot, a neck portion connecting the head to its arm and having its cross-sectional dimensions reduced so that the cutter can be turned in a slot already cut, and a pivot connecting the two arms disposed wholly below the work-supporting surface of the anvil, said surface being inclined relatively to the arm which carries it and extending rearwardly on either side of the cutting jaw.

5. A tool for cutting sheet material including in combination two arms, a slotted jaw carried by one of the arms forming a worksupporting anvil, the slotted jaw comprising similar side portions connected at their outer ends by a transverse part which closes the outer end of the slot, a cutting jaw carried by the other arm and adapted to cooperate with both the said side portions and also the said transverse end portion of the slotted jaw in the cutting of the material, and apivot connecting the arms disposed wholly below the level of the work-supporting anvil.

6. A tool for cutting sheet material including in combination two arms, a slotted jaw carried by one arm forming a work-supporting anvil, the slotted jaw comprising similar side portions connected at their outer ends by a transverse part which closes the outer end of the slot, a cutting jaw carried by the other arm and adapted to cooperate with both the said side portions and also the said transverse end portion of the slotted jaw in the cutting of the material, and a pivot connecting the arms disposed Wholly below the level of the work-supporting anvil, the work-supporting surface of said anvil lying in a plane which is raised above the arm which carries it and extending rearwardly to said arm on either side of the cutting aw so as to support the work around the cutting jaw above the level of the pivot and the hands of an operator.

7. A tool for cutting sheet material including in combination two arms, a slotted jaw carried by one of the arms forming a worksupporting anvil, the slotted jaw comprising similar side portions connected at their outer ends by a transverse part which closes the outer end of the slot, a cutting jaw carried by the other arm and adapted to cooperate with both the said side portions and also the said transverse end portion of the slotted jaw in the cutting of the material, a pivot connecting the arms disposed wholly below the level of the work-supporting anvil, and a movable fence adapted when moved into its operative position to determine the position in which the next slot is out.

In testimony whereof I have signed my name to this specification.

FREDERICK DONALD LINGWOOD.

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