US2490414A - Pinking scissors - Google Patents

Description

Dec. 6, 1949 J. J. CARNEY 2,490,414

PIIQKING SCISSORS Filed Sept. 27, 1946 I N VEN TOR. JHMES J CHRNE 4 a& u 3%A6 'a Patented Dec. 6, 1949 PINKING SCISSORS James J. Carney, Wethersfleld, Conn., assignor to The United Tool & Die Company, Elmwood, Conn., a corporation of Connecticut Application September 27, 1946, Serial No. 699,613

12 Claims.

This invention relates to pinking scissors and more particularly to such scissors as are intended for cutting sheet material such as cloth, or the like, and providing a pinked or staggered edge thereon which is especially suited for preventing unraveling of said material.

An object of this invention is to provide a. pinking scissors of a novel construction whereby it is rendered durable, economical to manufacture, and highly eiflcient in its operation.

A further object of the present invention is to provide a pinking scissors having novel means associated with the cutting edge of the scissors for retaining the sheet material in proper position relatively thereto to be cut with a pinked edge having a series of sharply defined points.

Further objects and advantages of this invention will be more clearly understood from the following description and from the accompanying drawings, in which- Fig. 1 is an elevational side view of a pinking scissors embodying my invention.

Fig. 2 is an elevational edge view of said scissors.

Fig. 3 is an enlarged view in vertical section on line 33 of Fig. 1.

Fig. 4 is an enlarged sectional view of a portion of said scissors on line 44 of Fig. 1.

Fig. 5 is an enlarged sectional view of a portion of the end of one of the blades of said scissors on line 5-5 of Fig. 1.

Fig. 6 is an enlarged fragmentary elevational view of opposite blade portions showing the formation of the cutting teeth therein.

Fig. 7 is a fragmentary elevational view of a piece of sheet material showing a cut made with my improved scissors.

Fig. 8 is a fragmentary elevational view of a portion of a scissors blade showing a piece of sheet material being cut therewith.

As shown in the drawings, my improved pinking scissors may comprise a pair of blades 5--5 having thereon suitable handles 66, the said blades being pivotally connected at 'l by means of a pivot screw 8 having a suitable nut 9 thereon with a spring washer In between said nut and the blades.

Each of the blades 55 has a flat side, which substantially normal to the axis of the pivotal connection, and a transverse edge with a series of teeth II which are formed crosswise in the said edge of the blade to provide a serrated cutting edge and are positioned in the blades so that the high points of the teeth on one blade and the low points of those on the opposite blade will be respectively on arcs having their centers substantially on the said axis of the pivotal connection and in register as clearly illustrated in Fig. 1 of the drawings. As shown in Fig. 3 of the drawings, it will be noted that the opposed sides of said blades are disposed parallel to each other on opposite sides of a central line indicated at A--A and that the notches forming the points of the teeth l2 are cut across the transverse edge of each blade as indicated at l3. It will also be noted that, during the operation of the scissors, the opposite rows of teeth move past each other and that the cutting edge on each blade runs along the sides of said teeth.

In order to retain the cloth, or sheet of mate rial, which is to be cut, in position so that the salad teeth will cut to leave sharply defined pinked edges, I provide a supporting surface by means of'a flange M which preferably extends from a cover IS on each blade and is disposed over and in front of the teeth l2 when the teeth on the opposite blades are moved relatively to each other during a cutting operation. The surfaces of the said flanges M will engage the sheet material, during the cutting operation and support it so that the scissors may be held perpendicularly to the plane of the cloth, in the conventional manner, and the portion of the sheet of material which is being cut will be disposed parallel to the sides of the teeth with the cutting edges thereon and the cut edge will thereby take the form of said teeth, as clearly shown in Fig. 7.

In order to prevent the accumulation of lint under the supporting flanges l4 and increase the efliciency of said scissors for cutting a pinked edge, I provide a series of notches in said flanges which are in register with the teeth l2 and form a row of teeth l8 that serve to engage the flexible material which is to be out by said scissors and support the said material, as clearly illustrated in Fig. 3, so as to ensure the cutting of a pinked edge with uniform teeth therein.

Means other than the flange l4 may be provided for retaining the sheet material in position relatively to the teeth in the same manner as above described. Such means may be in the form of a guard secured to the front edge of the blades and running along said edge over the teeth l2, or such guard or flange may be provided in other forms 50 long as a supporting surface is pro vided adjacent to and running overthe points of the teeth l2, as clearly described herein and illustrated in the drawings, for supporting the portion of the sheet material being cut so as to permit portions of said material to extend from the edge of the supporting surface to the cutting edge portion at the bottom of a tooth on one blade, while the supporting surface on the opposite blade supports the material so as to permit the cloth to be cut with the cutting edge portion at the top of said teeth.

If desired, the cover plates l5 may be secured as illustrated by mounting them between the head 8 or the nut 9' and their respective blade 5 for securing the plates thereon with supporting flanges I 4 extending inwardly across the tops of the teeth I: for a portion of the distance across the edges of the blades. The front ends of said cover plates may be bent backwardly, as at It in Fig. 5, to engage a beveled edge I! so as to lock the end of the plate to the blade against displacement thereon and prevent said plate from moving away during cutting operations.

During the operation of cutting a piece of sheet material, such as cloth or the like, the material is supported by means of the flanges ll, as clearly shown in Figs. 3 and 8, so that, as the blades are moved together, the portion of the material being cut is carried over the edges of the flanges l4 and between the cutting edges at the sides of the teeth [2, and a pinked edge will be cut as clearly illustrated in Fig. 7. While the illustration in Fig. 8 does not show the actual position of the material as it is being out between the two blades, it illustrates the relation of the sheet with the cutting edge of the teeth which results in the formation of the points or pinked edges illustrated in Fig. 7.

It has also been found that in order to provide for efllcient cutting operation of said scissors, it is of primary importance that the cooperating cutting edge portions on the opposite teeth be so formed that they will be relatively at an angle generally divergent in a direction away from the pivotal connection, so that the cutting point between the cutting edges of the blades will close progressively along the toothed formations of the opposite blades, and in a direction away from the pivotal point. To accomplish this purpose, the teeth on one of the blades 5 are preferably formed as clearly illustrated at 20 in Fig. 6 so that their movement, relatively to the teeth of the opposite blade, will bring the cutting edges past each other progressively along the toothed formation and without chopping action or jumps in the cutting as it is done by said scissors. In other words, the actual cutting of the material will take place up the rear edge of one tooth, down the front edge of said tooth, up the rear edge of the next tooth, down the front edge of that tooth, and so on for the full length of the blades. trated at II which shows the tapered relation between the cutting edges of the opposite teeth whereby the said cutting edges will open forwardly from the point of contact between them and continue in this relation for the full length I of the blades to provide maximum efliciency and prevent the points of the teeth on one blade from overriding the cutting edge of the opposite blade during a cutting operation.

While the teeth may be irregular, in order to properly register with those of the opposite blade, it will be noted from the illustration in Fig. 7 that the cut edges of the material will have uniform teeth therein. This isdue to the fact that,

This is particularly illus-' during the relative movement between the blades,

4 flanges ll are spaced from the actual cutting edge of the blades so as to permit clearance between the said free edges and the inner surfaces of the opposite blades for accommodating the thickness of the material being cut, as clearly illustrated in Fig. 3.

The said plates II also provide an additional advantage since they cover the shear blades completely and thereby eliminate the necessity of a high polish on said blades which is more expensive in manufacture than a polished or finished surface directly on the blades.

I claim:

1. A pinking scissors comprising a pair of pivotally connected blades, each blade having a side substantially normal to the axis of the pivotal connection and an edge transverse to said side, and a series of teeth cut crosswise in the said transverse edge for providing a serratedcutting edge along the side of the blade; the said teeth having high points and low points, each high point of one blade and the corresponding low point of the other blade being substantially in register and on an are having a center substantially at the axis of the said pivotal connection.

2. A pinking scissors comprising a pair of pivotally connected blades, each blade having a side substantially normal to the axis of the pivotal connection and an edge transverse to said side, and a series of teeth out crosswise in the said transverse edge and having high points and low points with cutting edge portions therebetween providing a serrated cutting edge along said blade; each high point of one blade and the corresponding low point of the other blade being substantially in register and the said cutting edge portions of one blade cooperating with corresponding portions of the other blade and forming therewith angles generally divergent away from the said pivotal connection.

3. A pinking scissors comprising a pair of pivotally connected blades, each blade having a side substantially normal to the axis of the pivotal connection and an edge transverse to said side, and a series of teeth out crosswise in the said transverse edge and having high points and low points with'straight cutting edge portions therebetween forming the sides of said teeth and providing a serrated cutting edge along the said blade; each high point of one blade and the corresponding low point of the other blade being substantially in register and on an are having its center substantially at the axis of the pivotal connection and each of said cutting edge portions of one blade cooperating with the corresponding cutting edge portion of the other blade and generally divergingtherefrom in a direction away from the said pivotal connection.

4. A pinking scissors comprising a pair of pivotally connected blades each having a side substantially normal to the axis of the pivotal connection and an edge transverse to said side, a series of teeth cut crosswise and providing a serrated cutting edge along the side of the blade, the said teeth having high points and low points, the high points of one blade and the corresponding blade of the other being in register and on an arc having a center substantially at the center of said pivotal connection, and means extending over the said transverse edge for supporting a sheet of material while being cut in said scissors.

5. A pinking scissors comprising a pair of pivotally connected blades each having a side substantially normal to the axis of the pivotal connection and an edge transverse to said side, a series of said teeth out crosswise in the said transverse edge and having high and low points with cutting edge portions therebetween providing a serrated cutting edge along said blade, each high point of one blade and the corresponding low point of the other blade being substantially in register and the said cutting edge portions of one blade corresponding with the said portions of the other blade and forming therewith angles generally divergent in a direction away from the said pivotal connection, a plate mounted to said blade, and a portion on said plate running along and over the said teeth'for supporting a sheet of material relative to said cutting edge while being cut in said scissors.

6. A pinking scissors comprising a pair of pivotally connected blades each having an inner and an outer side substantially normal to the axis of the pivotal connection and an edge transverse to said inner side, a series of teeth out crosswise in the said transverse edge and having high points and low point with cutting edge portions therebetween providing a serrated cutting edge along said inner side of the blade; each high point of one blade and the corresponding low points of the other being in register; the said cutting edge portions of one blade cooperating with the corresponding cutting edge portions of the other blade and generally diverging therefrom in a direction away from the said pivotal connection, and means on said blades providing a supporting surface extending over the said teeth forsupporting a sheet of material perpendicular to the inner sides of the blades and causing the portion of said material being cut to be disposed parallel to said inner sides for producing a pinked edge along the line of cut made by said serrated cutting edge.

7. A pinking scissors of the character described comprising a pair of pivotally connected blades each having an inner side and an outer side substantially normal to the pivotal connection and an edge transverse to the said sides, a series of teeth out crosswise in the said transverse edge and having high points and low points with straight cutting edge portions therebetween i'orming the sides of the teeth and providing a serrated cutting edge along the inner side of said blade; the corresponding low points of one .blade and the high points of the other blade being means extending across the tops of said teeth for supporting a material relatively to said teeth as it is being cut in said scissors.

9. A pinking scissors comprising a pair of pivotally connected blades each blade having a side substantially normal to the axis of the pivotal connection and an edge transverse to said side, a series of teeth out crosswise in the said transverse edge for providing a serrated cutting edge along the side of the blade, and means providing a support running along each of said blades and over the tops of said teeth for supporting a sheet of material relatively'to said teeth while beingv cut in said scissors.-

10. A pinking scissors of the character described comprising a pair of pivotally connected blades, each blade having a side substantially normal to the axis of the pivotal connection and an edge transverse to said side, a series of teeth out crosswise in the said transverse edge and providing a serrated cutting edge along the side of the blade, a cover secured to the outside of the blade, and a portion projecting from said cover from the said pivotal connection, a cover plate mounted upon the outer side of said blade, and a portion on said cover plate extending over the said teeth for supporting a sheet of material perpendicular to saidinner sides of the blades and causing the portion of said sheet being cut to be disposed parallel to the said inner sides for producing a pinked edge along a line of cut made by said serrated cutting edges.

8. A pinking scissors comprising a pair of pivotally connected blades, each blade having a side substantially normal to the axis of the pivoted connection and an edge transverse to said side, a. series of teeth out crosswise in said transverse edge for providing a serrated cutting edge along the side of the blade, and material supporting and running over the tops of said teeth for supporting a sheet of material relatively to said teethwhile it is being cut in said scissors.

11. A pinking scissors of the character described comprising a pair of pivotally connected blades each having a side substantially normal to the axis of the pivotal connection and an edge transverse to said side and running along the blade, a series of teeth out crosswise in the said transverse edge and providing a serrated cutting edge along the said side of the blade, a flange projecting inwardly over the said transverse edge and running along the tops of said teeth, said flange having a series of notches therein to permit the egress of lint and forming teeth in said flanges in register with the teeth in the said transverse edge and disposed perpendicularly thereto for supporting a sheet or material relatively to the said cutting edge while it is being cut in said scissors.

-12. A pinking scissors of the character described comprising a pair of pivotally connected blades each having an inner and an outer side substantially normal to the axis of said blade and an edge transverse to said sides, a series of teeth cut crosswise in the said transverse edge for providing a serrated cutting edge along the REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS

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