US3484940A - Cutting device - Google Patents

Description

Filed NOV. 13, 1967 ELL, JR 3,484,940

CUTTING DEVICE 2 Sheets$heet l INVENTOR. CHARLES C. ZELLJD! AGENT Dec. 23, 1969 c. c. ZELL, JR 3,434,940

CUTTING DEVICE Filed Nov. 13, 1967 2 Sheets-Sheet 2 INVENTOR, -C//4R4 55 c. 2&2) J

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United States Patent 3,484,940 CUTTING DEVICE Charles C. Zell, Jr., Los Alamitos, Califi, assignor to North American Rockwell Corporation Filed Nov. 13, 1967, Ser. No. 682,488 Int. Cl. B261) 1/08, 4/48; A6lb 17/32 US. Cl. 30--162 1 Claim ABSTRACT OF THE DISCLOSURE The invention described herein was made in the performance of work under a NASA contract, and is subject to the provisions of the National Aeronautics and Space Act of 1958, Public Law 85-568 (72 Stat. 426; 42 U.S.C. 2451) as amended.

Background In the manufacture of large complex electronic equipment, numerous wires are used to interconnect various points of electronic circuitry; these wires traversing many tortuous paths in order to terminate at desired places. It had been the practice, in so-called in-place wiring, to affix one end of the wire at its desired point; route the wire over a selected path; and to then aifix the other end of the wire to its designated location. As wires were sequentially positioned in this way, it was found that various wires tended to have parallel adjacent paths; and it became the practice to cable these wires into a bundle; that is, to lace the wires together with suitable lacing-cord. This cabling provided a neater appearance, and-in many casesa more rigid arrangement wherein the wires would not move when subjected to vibration or shock.

It was soon discovered that economies could be achieved if these wires were sub-assembled; that is, cabled together externally of the apparatus, to form a wire-harnessand the wire-harness then just dropped into place in the apparatus. If the wire-harness had been properly made, the ends of the various wires were automatically positioned at, or near, their desired terminating points.

As wire-harnesses became evermore larger and complex, it became necessary to temporarily bundle some wires, in order to provide a compact arrangement that permitted additional wires to be added. Therefore, temporary ties were used to form temporary cables; the string forming the temporary ties being cut and replaced by new ties that encompass additional wires as the wire-harness increased in size. At other times, a series of ties had to be cut away in order to add, remove, or repair a wire.

It was soon found, that-regardless of the operators skill, experience, and care-the devices used for cutting the temporary ties frequently slipped; and nicked or actually cut one or more of the wires in the wire-harness. The nicked or cut wires required repair; or even worse, if not corrected, caused a malfunction of the equipment that showed up much laterafter virtual completion of the apparatus. In an attempt to minimize harming the wires, many cutting implements were tried; these included ordinary knives and scissors, surgical scissors having protected points, seam-rippers, and other devices. Unfortunately, none of these cutting devices proved completely satisfactory.

3,484,940 Patented Dec. 23, 1969 Objects and drawings;

It is therefore an object of the present invention to provide an improved cutting device. The attainment of this object and others will be realized from the following detailed description; taken in conjunction with the drawings of which FIGURE 1 illustrates one embodiment of the invention;

FIGURE 2 illustrates an opened-up view of said embodiment;

FIGURE 3 illustrates a second embodiment; and

FIGURE 4 illustrates still another embodiment.

Synopsis Broadly speaking, the present patent application discloses a cutting tool wherein the cutting-element is nor mally sheathed; so that the cutting-edge remains hidden until it is intentionally brought into contact with a material to be cut. The various embodiments disclose an external hook for properly positioning the cutter; slots and/or apertures for positioning the material to be cut; a finger-hole for holding the cutter in a convenient, yet non-interfering position during ordinary work; clips for supporting the tool during non-use intervals, etc.

Description FIGURE 1 shows an embodiment that is specifically designed for cutting the ties of a wire-harness. As shown, cutter 10 is a hand held manually-operated device, comprising a housing 12--a portion thereof acting as a sheath for a cutting-element 14 having a cutting-edge 16. FIG- URE 1 shows cutting-element 14 partially advanced so that cutting-edge 16 is unsheathed. Normally-during non-use intervals-cutting-element 14 is retracted, as by means of a biasing spring, so that its cutting-edge 16 is sheathed; and cannot accidentally cut any of the wires.

In use, an elongated partially tapered hook 18 is engaged with the tie 20 to be cut. Hook 18 and housing 12 are configurated to form a narrow inlet 22 that communicates with a reentrant formation of the hook-housing to produce a cutting-aperture 24. Thus, the tie 20 to be cut slides through narrow inlet 22 into a suitably-shaped cutting-aperture 24. In order to cut the tie, a thumb-button 26 which is attached to cutting-element 14, is manually moved forward. This operation advances cutting-element 14, so that its cutting-edge 16 is unsheathed, as shown, and makes contact with tie 20. Due to the shape of the cutting aperture 24 and the angle of the cutting-edge 16, the forward movement causes cutting-edge 16 to slice across tie 20; and to thus cut it in a smooth efficient manner.

It will be noted that during the cutting operation, only the tie 20 is in contact with the cutting-edge 16. The wires of the harness, being perpendicular to tie 20, are not engaged by the cutting-edge 16; and moreover, the inlet 22 between book 18 and the body of housing 12 is so small that only the tie, and not the wire can enter. In this way, the disclosed cutter safely cuts the tie, without endangering or cutting the wires themselvesand does not expose the tie to any strain or pull that might cause it to cut into the wires insulation. Moreover, a finger-hole permits the operator to hold the cutting-device in a convenient, and yet non-interfering manner duringand between--cutting operations.

Ordinarily the tie to be cut has been tied fairly snugly 3 tie 20, and the housing rocked upwards in such a manner that fulcrum-portion 25 causes the hook-tip to tens1on the tie, and thus permit the now-loosened tie to slide along inlet 22 into cutting-aperture 24.

The embodiment of FIGURE 1 is shown in a disassembled form in FIGURE 2. Housing 12 comprises two substantially mirror-image parts 12a and 12b; and cuttingelement 14 is positioned in a blade-holder 30, whose rearend has a spring-pin 31 engaged by one end of an extension-spring 32 having its other end afiixed to an anchoring pin 3-4. Thus, spring 32 normally retracts cuttingelement 14 so that its cutting-edge 16 is safely sheathedas illustrated.

Each housing-half, 12a and 1212 has suitable recesses to receive blade 14, blade-holder 30, spring 32, and anchoring pin 34; the forward portion 36 of the recess being suitably sized and shaped to act as a slide-guide for blade 14. In the embodiment shown, one housing portion- 12b in this casehas threaded holes 38 for accepting screws 40 that hold together the two parts of the housing; the other housing-portion, 12a, having countersunk clearance-holes for positioning the holding screws 40. Alternatively, a plastic housing may have threaded inserts; or may be permanently bonded together.

As shown, blade-holder 30 has a blade-pin 33 for accepting the hole of blade 16, and has a threaded hole 35 for receiving the threaded shaft of thumb-button 26; and each housing-half has a suitable slot 42 for clearing the shaft of thumb-button 26, which may therefore be screwed into the blade-holder 30 from either side. Thus, thumb-button 26 may project from either side of the housing, in order to facilitate use by either right-handed or left-handed operators.

In order to prevent the tip of the blade from pressing against the housing, its forward motion is stopped by the abutting of the end of the thumb-button shaft against the end of its clearance slot, 42, or by the abutting of bladeholder 30 against the end of its guide-slot.

The housing shown in FIGURES 1 and 2 has a hook portion 18 at an angle of about relative to the longitudinal axis of the housing; this angular relation permitting easy insertion of the hook-tip under the tie to be cut, and still permitting sufiicient clearance for the hand of the operator to be positioned above the wire-harness. It will be noted that hook 18 and housing 12 co-act to form the relatively narrow opening or inlet 22 between the hook 18 and the body of the housing; this inlet being suitably proportioned and narrow so that only the tie, and not the wire, will be admitted into the cutting-aperture 24. Where desired, the movement of the blade may be such as to close the inlet, and to thus prevent the introduction of additional material into the cuttingaperture.

It has been found that if cutting-aperture 24 has a suitable shape, the advancement of cutting-edge 16 traps the tie at a corner of the cutting-aperture; and then slices cleanly across the tiethus producing an efiicient, clean, cutting action.

Alternatively, a compression spring may be used to bias the knife-edge to a normally advanced and sheathed position. In this case, the cutting action is produced by (1) retracting the blade, (2) admitting the tie into the cutting aperture; and (3) then advancing the blade for the cutting operation. 7

A somewhat ditferent arrangement is shown in FIG- URE 3. Here a compression-spring 48 abuts one end of blade-holder 50; and a trigger 52 has a pin 54 that passes through a suitable guide-slot in the housing, and through a hole 59 in the blade 56. In operation, trigger 54 is pulled back to compress spring 48 and is then releasedwhereupon the compressed spring drives the blade forward for the desired cutting action. If desired, trigger 52 may be designed and mounted to project upwards, downwards, or to either side.

As discussed previously, in order to prevent blade-tip pressure on the housing, the end of the guide slot acts as a stop for the trigger-pin; or else the slide-recess acts as a stop for blade-holder 50.

FIGURE 4 shows another embodiment, this comprising a housing that takes the form of a tube 60; suitable endplugs 62 being used to close the tube. A cutting-blade 64, having a width substantially equal to the inside diameter of the tube, is positioned within the tubeso that the inner surface of the tube acts as the sliding-guide. Thumbbuttons 66, fitting through longitudinal slots 68 and a hole in blade 64, prevent the blade from turning; and provide means for advancing the cutting-edge past cutting-aperture 70. In this embodiment, no blade-holder is used. This particular embodiment is illustrated as being entirely manual, dispensing with the previously-used biassing springs; and, if desired, a pencil-type clip instead of a finger hole.

In production processes other than cabling wire, bundles of material are tied in a similar manner; except that due to their weight, a tie of wire-rather than string-may be used. The cutter described in connection with FIGURE 3 can be readily modified for cutting these tie-wires; the modification involving the following changes. In order to cut the tie-wire, a slicing action is not particularly desirable; and should be replaced by either a shearing or pinching arrangement. For shearing purposes, a flattened cutting-edge is forced to pass closely against a firmly-fixed shear edge, to produce a shearing action of the scissortype. For a pinching mode of operation, a tapered cutting edge is forced against a tapered die, in the manner of the well-known diagonal-cutter. In these embodiments, it is desirable to use a stored force, rather than thumb pressure; and the spring and trigger mechanism of FIGURE 3 may be advantageously used-the spring force driving the edge of the cutter against the wire and the backup shear or die.

It will be noted that the disclosed arrangements are such that the cutting-edge, the material to be cut, and the users fingers are always protectedboth while the cutting-edge is fully, or only partially sheathed.

Although the invention has been described and illustrated in detail, it is to be clearly understood that the same is by way of illustration and example only, and is not to be taken by way of limitation; the spirit and scope of this invention being limited only by the terms of the appended claim.

What is claimed is:

1. A cutting device for cutting a wire-tie surrounding a bundle of wires, without cutting any of the wires, comprising:

a housing having a hook, a cutting-aperture, shaped to trap said wire-tie for cutting said wire-tie, and sheath means for sheathing a cutting-element, said cuttingaperture communicating with said sheath means, and the free end of said hook overlying a portion of said housing to coact therewith to form a narrow inlet that is suitably sized to admit a tie to be cut, and to exclude wires to be protected from being cut, said narrow inlet communicating with said cutting-aperture;

a cutting-element having a slicing-edge movably positioned in said housing;

means for guiding said slicing-edge of said cutting-element into and out of said cutting aperture and said sheath means-whereby said sheathed slicing-edge is protected from contact with all materials except those wire-ties capable of passing into said cuttingaperture, and these wire-ties may be contacted and cut by forward movement of said slicing-edge of said cutting-element;

biassing means, positioned in said housing, for retracting the slicing-edge into a normally sheathed position; and

means, comprising a finger-button affixed to said cuttingelement, for overcoming said normally sheathed state, and manually advancing said slicing-edge into said cutting-aperture in a slicing manner.

References Cited UNITED STATES PATENTS 896,117 8/1908 Jones 30-13 X 2,198,111 4/1940 Gorbatenko et a1 30-162 2,541,063 2/1951 Hubbard 30-184 X 6 2,615,181 10/1952 McGaughey 30-182 X 2,674,083 4/1954 Lezzeni 30-182 X 2,722,740 11/1955 Hubbard 30-241 X GIL WEIDENFELD, Primary Examiner US. Cl. X.R.

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