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Publication numberUS1305513 A
Publication typeGrant
Publication dateJun 3, 1919
Filing dateOct 29, 1915
Publication numberUS 1305513 A, US 1305513A, US-A-1305513, US1305513 A, US1305513A
InventorsWilliam A. Bernard
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
US 1305513 A
Abstract  available in
Previous page
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Claims  available in
Description  (OCR text may contain errors)



1,305,513. Patented June 3,1919.


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Specification of Letters Patent.

Patented June 3, 1919.

Application filed October 29, 1915. Serial No. 58,716.

To all whom it may concern:

Be it known that I, WILLIAM A. BERNARD,

'a citizen of the United States, residing in the city and county of New Haven, State of Connecticut, have invented certain new and useful Improvements in HandTools, of which the following is a full, clear, and eX- act description. 7 This invention relates to hand tools, and more particularly to a tool of the plier type which is especially adapted for use by electricians in manipulating insulated wire. There is at present on the market a certain type of insulated wire or conductor, in which the ordinary insulation is inclosed in a metal sheath formed of layers of thin metal wrapped around the wire and soldered to gether. One of the primary objects of my invention is to provide an eficient tool for removing this metal sheath from any desired portion of the wire. It is also aimed to provide a tool having provision for cutting this sheathed insulated wire, and for clamping orgripping the same in an effective manner without Inutilating or deforming it.

To these and other ends, the invention consists in the novel features and combinations of parts to be hereinafter described and claimed.

In the accompanying drawing, Figure l is a side elevation of a hand tool embodying my improvements, showing the jaws open; 7

'Fig. 2 is'a similar view with the jaws closed; 7

Fig. 3 is a front end view of the tool with the jaws open, the handles being omitted;

Fig. 4 is an enlarged plan view of a portion of one of the jaws;

Fig. 5 is a section on line 55 of Fig. 4:; and i F i 6 is a detail (on a somewhat smaller scalefi hereinafter described.

I have shown my improvements applied to a tool of the plier type having the socalled parallel jaws 7, 8, actuated by pivoted sheet-metal handles 9, 10; but in certain aspects of the invention these features are not material. In the form illustrated, the forked portions of the levers 9, 10 cross each other, and are pivoted together at 11. The jaw 7 is pivoted in the well-known manner jaw 8 is pivoted to the forward extremity 7 14 of lever 9, and slides on a pin 15 oarried by the lever 10. The jaws 7, 8 have at their forward or nose portions the usual gripping surfaces 7*, 8 which are serrated, as shown in Fig. 4. In the embodiment illustrated, a cutter for removing the metal protective sheath from the insulated wire is located immediately at the rear of the serrated gripping surfaces 7 8 Inconstructing this cutter, the jaws 7, 8 are provided with opposing semi-cylindrical depressions 7 8", each of which extends transversely across the corresponding jaw. When'the jaws are brought together, these depressionsf7", 8 form in conjunction a round opening adaptedto completely inclose the wire. Adjacent one of the side faces of the tool, the depressed portions or seats 7 8 are provided with cutting teeth which, when the jaws are closed together, as shown in Fig. 2, form a ring-like toothed cutter to cut through the metal sheath surrounding the insulated wire. In the form shown, each semi-cylindrical seat is provided at one'side of the tool with three sharp teeth 16 formed integral with the jaw and arranged in-a series which is directed longitudinally of. the jaw and trans versely of the two-part cylindrical seat for the wire. 7 V

In the embodiment illustrated, a cut-o1f device for severing the wire is located at the rear of the cutter just, described. The jaws are provided with opposing semi-cylindrical depressions 17, 18, which extend transversely of said jaws, and are generally similar to the depressions 7 8 One of the jaws, for instance jaw 7, is provided at one side with a detachable cutting blade 19 secured to the side face thereof by small screws 20. As

beveled edge of the cutting blade 19 substantially semi-circular in shape.

At the top of the cutting blade 19, the same is provided with a smaller semi-circular cutting edge 22, which is in substantial registry with a transverse groove 23 eX tending across the outer surface of the jaw 7 for the purpose hereinafter described.

The pins 24, 25 which connect the forward extremities of the levers 10, 9 respectively with the jaws 7, 8 respectively are formed with heads 26, 27 adapted to clamp or grip the sheathed wire. For this purpose, these heads 26, 27 are made in the form of rounded studs having annular grooves 28, 29. When the jaws are brought together, as shown in Fig. 2, the opposing portions of the grooves 28, 29 are brought into close proximity so that a wire placed alongside the tool in a lengthwise direction may be gripped between the studs 26, 27 in an obvious manner.

In using the improved tool for the manipulation of insulated electric wire having a metal protective sheath, the procedure is as follows: Supposing that it is desired to remove the sheath from a portion of the wire, the wire is clamped in the seat formed by the depression 7*, S so that the teeth 16 bite into the metal sheath at different points in the periphery of the same. The teeth 16 are not forced into the sheath under great pressure, but are caused to bite into the same slightly. The operator then oscillates the too-1 on the wire by moving the handles to and fro so that the teeth 16 traverse the entire periphery of the sheath, and gradually cut through the same. By the time the teeth have completely penetrated the metal sheath, the opposing portions 7*, 8 of the jaws will have come into contact with each other, so that the teeth will not cut into the insulation material which is disposed between the sheath and the wire proper. Thus when the tool is properly designed with respect to the wire which it is desired to manipulate, the jaws form a gage for limiting the out made by the teeth 16. As soon as the sheath has been completely severed along a transverse line, that portion which is to be removed is flattened by compressing it between the serrated portions 7, 8 of the jaws, so as to break the soldered connection between the several layers of the metal wrapping, after which the free end of the wrapping may be grasped between the forward ends of the jaws so as to unwrap and remove the metal covering. This operation of severing the sheath and removing the same can be carried out with the greatest ease and despatch.

The operation of the cutter 19 in cutting the sheathed insulated wire to length will be obvious from the foregoing description, since when a length is to be cut from the sheathed insulated wire, the wire is simply laid in the depression 18 and the handles 9 and 10 are grasped to force the cutter blade 19 through the metal sheath and the insulated wire inclosed therein.

Supposing that the insulation is removed from a portion of the wire in order to make an electrical connection, the naked wire can be readily cleaned and brightened so as to make a good electrical contact by running it through the groove 23 on the jaw 7 so that the surface of the wire is scraped off clean by the sharp edge 22.

The studs 26, 27 are of particular advantage in gripping the sheathed insulated wire when it is desired to pull or straighten the same, because the annular grooved portions of the studs conform to the contour of the wire and prevent the protective sheath from being deformed or mutilated. Of course, the jaws serve as a sort of gage for these studs, the arrangement being such that when the jaws are brought into contact with each other, the studs will be so spaced from each other as to grip the wire very firmly without, however, giving it any appreciable dent or mutilation. The advantage of these gripping studs will be understood when it is stated that if it were attempted to pull the wire by gripping it between the gripping surfaces 7 8 it would be flattened out and the protective sheath would probably be broken, all of which is avoided by using the studs 26, 27 for this purpose. The studs are also of advantage in holding the wire while it is being bent.

In order to insure the proper alinement of the jawsas the same approach each other,

I prefer to'employ a guide pin 30 carried by one of the jaws (for example, the jaw 7 and working in a comparatively tight socket 31 in the other jaw.

Various changes in the details of the construction may be adoptedwithoutdeparting from the scope of the invention as defined in the claims.

l/Vhat I claim is 1. A tool such as described, comprising a pair of pivoted handles, parallel jaws operated thereby, said jaws provided with transversely directed complemental seats, each of semi-cylindrical form,'and a transverse row of cutting teeth projecting from the cylindrical surface of each seat; substantially as described.

2. A. tool for stripping the metallic sheath from an insulated electric wire provided with such a sheath, comprising a pair of jaws having transverse substantially semi-cylindrical complemental seats at the inner opposing portions thereof, and a cutting device the cutting edge of which pro trudes slightly beyond the curvature of one of said seats adjacent one side face only of the corresponding jaw, said cutter proj ecting inward with respect to the substantially cylindrical seat formed by the two seats in conjunction, to such an extent as to out completely through the sheath at ap proximately the same time that the jaws come into contact with each other; substantially as described.

8. A tool for operating on electric wire having a sheath, comprising a pair of parallel jaws having plier portions on the working faces thereof at the nose portion of the tool, said jaws provided behind said plier portions with transverse semi-cylindrical complemental seats vextending throughout the width thereof, and a cutting device with a curved cutting edge associated with one of said seats at one side face of the tool, said cutterprojecting inward with respect to the substantially cylindrical seat formed by the two seats in conjunction, to such an extent as to cut through the sheath of the wire without severing the wire, said seats having smooth cylindrical surfaces through- Gopies of this patent may be obtained for five cents each, by addressing the out the major portion of their length which will not injure the wire; substantially as described.

4:. A tool for operating on sheathed electric wire, comprising a pair of parallel jaws having transverse substantially semicylindrical complemental seats extending across the respective jaw faces and adapted to register with each other, and a cutting device comprising a curved series of cutting teeth located in each of said seats adjacent one side face only of the tool, said teeth projecting inwardly with respect to the substantially cylindrical seat formed by the two seats in conjunction, to such an extent as to sever the sheath of the wire without severing the wire itself; substantially as described. 7

In witness whereof, I have hereunto set my hand on the 28th day of October, 1915.


Commissioner of Patents,

Washington, D. G.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2902894 *Jan 11, 1957Sep 8, 1959Koos Jr MiltonWire stripper
US3125909 *Mar 14, 1961Mar 24, 1964 figure
US3237300 *Mar 25, 1963Mar 1, 1966Dorothy Townsend MaryInsulation cutting pliers having parallel longitudinal and transverse cutting edges
US3707041 *Mar 18, 1971Dec 26, 1972Bendix CorpShield termination apparatus
US4630406 *Sep 20, 1984Dec 23, 1986Mechtrix CorporationMethod of using an elliptical form to generate a perfect radius in an insulated electrical conductor stripping blade
US6324712May 16, 2000Dec 4, 2001Victorinox AgPlier jaws having a wire cutting structure
US6473925Sep 27, 2000Nov 5, 2002Ideal Industries, Inc.Hand-held wire cutter with enlarged gripping surface
US20070006389 *Jul 8, 2005Jan 11, 2007Cotter Timothy JElectrician's tool having multiple capabilities
U.S. Classification81/9.44, 30/90.1, 30/91.1
Cooperative ClassificationH02G1/1224