US2695537A - Coaxial cable stripper - Google Patents

Description

1954 w. D. IMMAN ETAL COAXIAL CABLE STRIPPER Filed April 8, 1952 IN V EN TORS.

[1/4/11 0 Mid/HIV United States Patent Ofifice 2,695,537 Patented Nov. 30, 1954 COAXIA-L CABLE STRIPPER William D. Imman, (Iarmichael, and Myron E. J. Fuller, Sacramento, Calif.

Application April 8, 1952, Serial No. 281,256

2 Claims. (Cl. 819.5)

(Granted under Title 35, U. S. Code (1952), see. 266) The invention described herein may be manufactured and used by or for the Government for governmental purposes without payment to us of any royalty thereon.

This invention relates to a cable stripper especially adapted for use with coaxial cable, but which may also be used with other kinds.

One object of the invention is to provide a tool capable of producing at one operation, a cable end having two stripped shoulders, one at the junction of the projecting bare wire with the rubber jacket and tubular conductor and the second one at the junction of the tubular conductor with the outer covering of the cable, which may be covered with metallic braid.

Another object is to produce a tool of the above character, the tool being of small dimensions and being readily portable in an electricians tool box.

Another object is to produce a tool of the above nature in which the amount of wire to be uncovered by the cut is readily adjustable, but which will stay constant for many cuts until purposely changed.

A still further object of this invention is to provide a cable stripper which has a limiting means and cutter means located at predetermined positions so as to remove in one operation a predetermined amount of insulation from the cable to be stripped.

Referring now to the drawings, Fig. l is a side elevation of the stripped cable end to be produced by the tool, the original dimensions being indicated by dashed lines and the knife positions by dotted lines.

Fig. 2 is a perspective view of the tool, together with a length of cable which is to be worked upon. The cable holding means (a vise and semi-cylindrical block therein) is shown in dashed line.

Fig. 3 is a side elevation of the tool and cable shown in Fig. 2.

Fig. 4 is a vertical section taken on the line 4-4 of Fig. 3.

Referring now more particularly to Figs. 2 and 3, 1% is a cylindrical hollow body, the forward end of which is partially cut away to form a shouldered portion 11. The portion 11 is adapted to act as a rest for the cable 12 which is to be stripped. The free end of the cable 12 is fitted into the body until it meets a cylindrical stop 13 (see Fig. 3) which is slidable with a fairly close fit in the bore 14 of the body 10. A screw 15, which has a large knurled head 16, is threadedly engaged in the stop 13 and is adapted to engage the interior wall of the body 10 at its highest points. The screw 15 projects through a slot 17 which is preferably slightly shorter than the length of the stop 13. The knurled head 16 is preferably at such a distance from the bottom of the body 10 so that whenthe screw engages the interior wall of the body the knurled head 16 can act as a support for the entire tool on a bench surface (not shown), but the relation of which. to head 16 and to a vise 18, may readily be adjusted. The vise 18 is provided with a pair of mated semi-cylindrical blocks 19a and 1917, which are hollowed just sufiiciently to hold the cable 12 tightly between them when the vise 18 is tightened, without crushing the cable.

Attached to the top of the cylindrical body 10 at the rear thereof, by screw 20, there is a long spring 21 on the extreme outer end of which is a short triangular knife 22 and further in from the end is a longer knife 23 of the same kind. The possible depth of insertion of the knife 22 should correspond to the height of the shoulder 24. This shoulder is shown in Fig. 1. The length of possible insertion of the knife 23 shouldbe that of the height of the shoulder 25, shown in Fig. 1, plus the height of the shoulder 24. For other kinds of cable requiring different dimensions of cuts, the entire knife assembly, i. e. 21, 22, 23 may readily be removed from the body 10 by loosening the screws 20, and a different knife assembly of different dimensions affixed to the body by again tightening these screws.

As will be seen in Figs. 2 and 3, the knife assembly may be subjected to pressure from a pad 26 to which is loosely attached the screw 27, which is: also provided with an upwardly projecting. knurled head 28. The screw 27 threadedly engages the boss 29, which is preferably integral with an oblong collar 30, the lower end 31 of vhich is curved to fit the body 10. A hole 32 through .vhich the knife 23 may pass as it is forced into the cable 12 under the urging of the screw 27, is provided in the body 10 at the top thereof just behind the shoulder 11. The short cutter 22 will enter the cable :in front of the shoulder 11, while the long cutter 23 will enter the cable a predetermined fixed distance behind the short cutter 22. Therefore no time will be lost in fixing the distance between the cuts since this will be predetermined once and for all when the knives are afiixed to the spring 21, preferably by the process of silver-soldering.

Referring to Fig. 4, the positions of the knives 22 and 23 may be readily seen. The knife 23 extends through the embedded hollow conductor 33 of the cable 12 while the shorter one 22 extends only to the surface of the hollow conductor 33. The cutter 23 extends all the way to the inner wire 34 but only to the surface thereof; the conductor 22 will extend only to the top surface of the conductor 33 when the screw 27 is tightened down so fully that that part of the spring 21 between the two cutters rests on the surface of the body 10.

After the cutting knives 22 and 23 have been thus forced into-the cable under the action of the screw 27 through manual rotation of its head 28, the tool is rotated m nually by means of a T handle 35 whichis fitted through the body 10 at right angles thereto near that end of the body which is furthest from the shoulder 11. The entire assembly is rotated around the cable about three times, more or less, while the cable is held motionless in the vise 18 and blocks 19a and 19b. Two clean cuts will be produced under these conditions. The tool is no removed from the cable by grasping the T ha dle 35 and pulling the entire tool away from the cable end. This action strips the two layers of covering and will leave the cable in condition shown in Fig. 1. After the screw 27 is loosened to allow the spring 21 to lift the knives. the severed ends of the cable insulation can and sho ld be shaken out of the tool preparatory to the next cut. The stop 13 may, of course, be set to obtain v rious lengths of bare central conductor wire by sliding it and the associated screw 15 forward or backward in the slot 17 and ti htening the screw at the selected position.

We claim as our invention:

1. In a device for stripping cable ends to make a pluralitv of shoulders thereon, a hollow cylindrical bodv, adjustable stop means within said body, a spring strip attached to said body near one end thereof. a pluralitv of spaced triangular knives of ditferent lengths attached at an angle to the non-attached end of said spring strip, manually-actuable pressure-applying means mounted substantially on the other end of said body engaging said spring strip to exert pressure downwardly on the end of said spring strip from a point above said knives to embed said knives in said cable jackets and lever means mounted substantially at that end of said body furthest from said knives whereby all of said foregoing elements mav be r tated with said cable end as an axis to separate portions of said iackets from the conductor portions of said cable.

2. In a device for strippin the end of a coaxial cable to form a plurality of shoulders thereon, a hollow cylindrical body having a partially cutaway portion proiecting lonqitudinallv therefrom for the support of a cable end. a m nuallv adiustable cvlindrical stop for the cable end within said cylindrical body, a spring strip mounted by one end thereof on said body to project normally at a low angle therefrom. a pair of triangular knives of different lengths attached at a spaced interval to the nonattached end of said spring strip, said body being provided with an opening for the rearward one of said knives to enter the body and penetrate the cable, the outer knife extending into said partially cutaway portion, means for exerting downward pressure on the end of said strip and said knives, said means comprising a strap attached to said body and arising therefrom to form a substantially rectangular structure, a 'manually rotatable screw threadedly mounted in the top of said structure and engaging the top of said strip through a pad, and a handle mounted crosswise of the body on that end to which the strip is attached whereby the entire assembly of the foregoing parts may be manually rotated with the cable as an axis to cut a length of tubular conductor and at least two lengths of associated insulation from said cable to form two spaced shoulders thereon.

References Cited in the file of this patent Number Number UNITED STATES PATENTS Name Date Williams Dec. 22, 1925 Wachstein Aug. 10, 1937 Edwards June 14, 1938 Hufi Dec. 20, 1938 FOREIGN PATENTS Country Date Denmark Mar. 16, 1908

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