US3532011A - Cut-off type wire stripper - Google Patents

Description

970 M. w. BRADLEY 3,532,011

CUT-OFF TYPE WIRE STRIPPER Filed Feb. 8, 1968 I N VENTOR MAR/0N 14/. BRADLEY ATraQA/E y ice Patented Oct. 6, 1970 3,532,011 CUT-OFF TYPE WIRE'STRIPPER Marion W. Bradley, Box 502, 6159 Berkshire Way, Paradise, Calif. 95969 Filed Feb. 8, 1968, Ser. No. 703,998 Int. Cl. H02g 1/12 U.S. Cl. 81-95 6 Claims ABSTRACT OF THE DISCLOSURE A lightweight, portable device that may be held in a hand of a user to sever a wire and strip a section of insulation of predetermined length from an end portion of the cut wire.

BACKGROUND OF THE INVENTION Field of the invention The present invention relates to the field of insulation strippers and wire cutters.

Description of the prior art In the past, numerous devices have been involved and used in stripping insulation from a wire to expose a bared end portion of wire that is connected to a terminal or spliced to another bared end portion of wire. The length of the insulation so stripped from a wire is left to the judgment of the user of the stripper or measurements the user may make.

During the past few years, devices have been developed and come into extensive use by which a bared end portion of wire of a precise length may be tension wrapped about a connector or terminal to effect an electrical connection therewith without the use of solder. A bared wire end portion of either too little or too great length impairs the forming of such a tension wrapped connection.

The present invention when used permits a length of insulated wire to be cut from a coil, and a section of insulation of a predetermined length stripped from an end portion of the cut wire Without relying on the judgment of the user of the device or measurements he may make.

SUMMARY OF THE INVENTION A portable lightweight device that may be held in the hand of a user to sever a length of insulated wire, and strip a section of insulation of a desired length from one end of the cut wire portion.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of the combined wire cutter and insulation stripper;

FIG. 2 is a side elevational view of the device with a length of insulated wire extending longitudinally therethrough;

FIG. 3 is the same view as FIG. 2, but after the Wire has been cut;

FIG. 4 is a side elevational view of the device after it has stripped a section of insulation of a predetermined length from an end of a cut portion of the wire; and

FIG. 5 is a longitudinal cross-sectional view of the wire cutter, taken on the line 5-5 of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawing, it will be seen thatthe combined wire cutter and insulation stripper tool A is shown in perspective in FIG. 1.

Tool A includes an elongate rigid body that has a first upwardly and rearwardly curved end 12 and a second downwardly and forwardly curved end 14. Curved ends 12 and 14 are longitudinally spaced a suflicient distance to permit the body 10 to be gripped in the hand of a user (not shown).

A groove 16 having cutting edges 18 is formed in the first curved end 12, and is used for stripping insulation 20 from a wire 22. When edges 18 are in engagement with insulation 20, and the wire 22 is pulled forwardly relative to the tool A, the section of insulation rearwardly of first end 12 is stripped from the wire. The shape of the groove 16 is shown and described in detail in my Pat. No. 3,180,184 entitled Wire Insulation Stripper that issued Apr. 27, 1965. Second curved end 14 is preferably covered with a layer of plastic or other inert material. When the body 10 is gripped in the palm of the hand of a user (not shown) the second curved end 14 prevents the body inadvertently slipping therefrom.

Body 10, in addition to defining the cutting edges 18 for stripping insulation 20 from a wire 22, also serves as a mounting for a wire cutting assembly B, as may best be seen in FIG. 1.

The assembly B includes a rigid rectangular base 24 that is secured to the upper side 10a of body 10 by a screw 27 or other suitable fastening means. Base 24 is disposed at an intermediate position between curved ends 12 and 14. A clevis 26 extends upwardly from one longitudinal side portion of base 24. The clevis 26 supports a transverse pin 28 that has a lug 30 pivotally mounted thereon.

Lug 30 is afiixed to the underside of an elongate pressure plate 32. The pressure plate 32 has a cutting member 34 extending downwardly therefrom. The forward edge portion 24a of base 24 tapers downwardly and rearwardly as does a rearward transverse edge surface 34a of cutting member 34. Edge portion 24:: and edge surface 34a have substantially the same radius of curvature 36 that originates at the center of pin 28, as may best be seen in FIG. 5. The edge surface 34a and a lower surface 34b of member 34 cooperate to define a transverse cutting edge 34:: where they intersect.

The edge surface 34a slides downwardly over edge portion 24a when wire 22 is severed as shown in FIGS. 3 and 4. The upper extremity of edge portion 24a is spaced a distance C from the part of the cutting edges 18 that engage the insulation 20 when the wire 22 is disposed in tool A as shown in FIG. 2. Upon the cutting member 34 being pivoted downwardly relative to base 24, as shown in FIG. 3, the wire 22 is severed, and insulation 20 stripped from a section 22a of the wire 22, when the wire is drawn forwardly relative to tool A as shown in FIG. 4. The stripped section 22a of the wire 22 shown in FIG. 4 is of length C.

To prevent the cutting edge 34c being dulled by pressure contact with surface 10a of member 10, the forward, upper edge portions 26a of clevises 26 are formed flat to act as stops when cutting member 34 has pivoted to the position shown in FIG. 3. Pressure plate 32 is normally disposed in the upwardly and forwardly extending position shown in FIG. 2 due to a compressed helical spring 38 or other resilient means being disposed between base 24 and plate 32. The ends of spring 38 are preferably positioned in cavities 32a and 24b formed in plate 32 and bore 24 as shown in FIG. 5.

The use and operation of the tool A has been previously described in detail and need not be repeated.

What is claimed is:

1. A portable tool capable of being held in the hand of a user to cut an insulated wire and strip a section of insulation of a predetermined length from the cut portion of said wire, said device including:

(a) an elongate rigid member having a first forwardly disposed curved end that extends upwardly and rearwardly, said first curved end having a groove formed therein that is bounded by sharpened edges that sever insulation from said wire when in engagement with said insulation and when said wire is moved forwardly relative to said member;

(b) a base rigidly afiixed to the surface of said member from which said first curved end extends upwardly, said base having a forward end surface that has at least a portion thereof longitudinally spaced from the part of said sharpened edges that engage said insulation at said predetermined length;

(c) a pressure plate;

(d) first means for pivotally supporting said pressure plate from said base;

(e) a cutting member supported from said plate and extending towards said rigid member, said cutting member having a transverse cutting edge that severs said wire when the insulation thereof is engaged by said sharpened edges and said pressure plate and cutting member are moved from a first position in which said cutting member is outwardly spaced from said base to a second position where said cutting member at least partially overlaps said forward end surface of said base;

(f) stop means for preventing said cutting edge contacting said rigid member; and

(g) resilient means that at all times tend to maintain said pressure plate and cutting member in said first position.

2. A portable tool as defined in claim 1 in which said first means includes:

(f) a clevis secured to said rigid member;

(g) a transverse pin supported by said clevis; and

(h) a lug aifixed to said pressure plate, with said lug having a transverse opening therein that pivotally engages said pin.

3. A portable tool as defined in claim 2 in which said forward end surface of said base and at least a part of the rearward surface of said cutting member are angularly disposed relative to said rigid member and slidably contact one another when said cutting member moves to said second position.

4. A portable tool as defined in claim 3 in which said forward end surface and said part of the rearward surface have substantially the same radius of curvature.

5. A portable tool as defined in claim 3 in which said stop means are defined by forward outer edge portions of 15 said clevis.

6. A portable tool as defined in claim 3 in which said resilient means is a compressed, helical spring that extends between said base and pressure plate.

References Cited ROBERT C. RIORDON, Primary Examiner 30 R. V. PARKER, 1a., Assistant Examiner

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