US3599913A

US3599913A - Cable grip

Info

Publication number: US3599913A
Application number: US862895A
Authority: US
Inventors: Joseph Dipalma
Original assignee: Individual
Current assignee: Individual
Priority date: 1969-10-01
Filing date: 1969-10-01
Publication date: 1971-08-17
Anticipated expiration: 1988-08-17

Abstract

A contractable cable grip of the split or nonsplit type adapted to grip and support a cable in a conduit riser has an elongate body of diagonally interwoven wires depending from a loadsupporting annulus adapted to fit in and engage the vertical conduit riser to support a cable therein, each wire having a strand extending up through a hole in said annulus and a strand extending down through an adjacent hole when a loop portion engages the upper surface of the annulus, the pair of strands immediately below the annulus being secured tightly together to prevent the strands from pushing back through the holes when pressure is applied to the annulus while the cable grip is forced over the cable into the conduit riser. The annulus of the split grip consists of two semicircular pieces detachably held together by an aligning pin on each piece extending into a hole in the other piece, the annulus having depending lugs to locate it centralized in the conduit.

Description

United States Patent Joseph Dil alma [72] lnventor Merritt St., South Norwalk, Conn. 06854 [21] App]. No. 862,895 [22] Filed Oct. 1, 1969 [45] Patented Aug. 17, 1971 [54] CABLE GRIP 6 Claims, 5 Drawing Figs.

[52] US. Cl 248/60; 24/123 F, 248/309 [51] lnt.Cl. F161 3/00 [50] Field of Search "248/60,

[56] References Cited I UNITED STATES PATENTS 1,686,250 10/1928 Page 24/123 A 1,994,674 3/l935 Van lnwagen 24/123 A, 1 2,681,781 6/1954 Kellems 248/60 f 2,847,244 8/1958 DiPalma 24/123 A 3,399,853 9/1968 Lewis 2,740,178 4/1956 Kellems Primary ExaminerChancellor E. Harris Attorney-Johnson & Kline ABSTRACT: A contractablecable grip of the split or nonsplit type adapted to grip and support a cable in a conduit riser has an elongate body of diagonally interwoven-wires depending from a load-supporting annulus adapted to fit in and engage the vertical conduit riser to support a cable therein, each wire having a strand extending up through a hole in said annulus and a strand extending down through an adjacent hole when a 'IIIIIIIIII. 'II/IIIII/I 'IIIIIIII/IIl' PATENTEUAUGWEQH 3.599.913

INVIZNTOR.

I losep/L DU aZ/na,

HTTORA/E Y5 CABLE GRIP This invention relates to cable grips, and more particularly diagonally interwoven wires forming an open mesh tubular body adapted to be placed over or around the cable so that when force is applied to the load-bearing member and the end of the body in opposite directions, the elongation of the tubular body causes its diameter to be reduced and the cable 'to be gripped by the body.

The load-bearing body is in the fonn of an annulus having an annular series of pairs of holes through which the wires of the body are threaded, each pair forming a loop engaging the top surface of the annulus and depending strands which are interwoven.

The diameter of the outer marginal portion of the annulus is such that when the grip is in position on theriser, the outer marginal portion of the annulus engages the end of the riser or fitting attached thereto.

Heretofore when force was applied to the load-bearingannulus for the purpose of pushing the grip into the conduit riser, the portions of the wire strands adjacent the annuluscould be pushed upwardly through the holes in the annulus with the result that, after the annulus was seated in the riser conduit, force would have to be applied to the loops to push the strands down against the annulus; otherwise the load of the cable would not be taken by the annulus. In forcing the strands of wire down through the holes in .the annulus, the loop portions were liable to be crushed or bent or otherwise distortedso that the load on the wires would not be evenly distributed on the annulus.

An object of this invention is to prevent such upward movement of the strands through the annulus, andthis is accomplished in the forms of the invention herein illustrated by causing the portions of each pair of strands of wire between the annulus and the portions of the strandswhich are interwoven to be tightly secured together under the annulus and thus close the loop.

In one form of this invention, each pair of strands is secured together by twisting the wires for a substantial distance below the annulus; and, in another form of the invention, the wires are held together by an encircling band of metal. In either event, the portions of the wires brought together prevent the wires from moving upwardly through the holes of the annulus.

According to the present invention, the annulus is provided with depending lugs spaced inwardly from their peripheral margins and positioned to engage the inner surface of the conduit riser to centralize the annulus in the conduit. 1

According to the present invention, the annulus for the split cable grip is preferably made of two separable parts so that the cable can be received between them, and these parts are held together by an aligning pin on each part engaging a hole in the other part.

Other features and advantages will hereinafter appear.

In the accompanying drawings:

FIG. 1 is an elevation of the split cable grip applied to a cable showing in section a portion of the conduit riser and] annulus In common with cable grips as heretofore provided, the grip.

of the present invention comprises a load-bearingannulus having'a circular series of holes 11, and a body 12 comprising a plurality of interwoven wires 13 each extending from the lower cable-receiving end 14 continuously to the annulus 10 where it extends up through a hole 1 1 in the annulus and down through an adjacent hole 11 and having a flattened loop portion 15 engaging an upper surface 16 of the annulus. Below the annulus l0, strands 17 of wires 13 are diagonally woven to produce the body 12. When the grip isappliedto a cable C, the load of the cable which is applied to the annulus by the body'of the grip causes the body to elongate and the woven strands to constrict upon the cable and grip it.

One of the functions of the cable grip of the present invention is to absorb the load of a vertically extending cable at the top and/or at thedeterminate positions alongthe height of the cable, depending on the weight of the cable for a given size and length. In practice, the cable is contained in a vertically installed rigid metal conduit or riser 18, sections of which are connected by one or more couplings to provide the desired length, the riser being securedto the building against movement.

The load-supporting annulus 10 has a diameter to fit within the coupling 19, or other fitting attached to the riser, and engage the end surface of the riser and thereby transfer the load of'the'cable to the riser. According to the present invention, the annulus is centered in the riser by means of lugs 20 which have their outer surfaces 21 arcuate to engage the inside surface of the riser 18.

When the grip is intended for application to the end of a cable which is being initially installed, the strands 17 may be woven to form a tubular body 12a and the load-bearing member maybe an integral annulus 10a shown in FIG. 5. In this-situation, the end of the cable being installed is inserted through the receiving end 14 of the body and forced through the'body and the annulus 10a, and the annulus and body are forced downward so that the annulus engages the riser 18.

When the grip is to be used on an intermediate portion of the cable, i.'e., when the end of the cable is not available, the annulus 10, as shown in FIGS. l'to 4, is made to comprise two semicircular parts 22 and the wire strands 17 are interwoven to provide a split 23 which permits the annulus to be parted and the body to be spread to admit the cable. Three pairs of strands are attached to each part 22 so that when the parts 22 are separated, the space aligns with the split 23.

For the purpose of joining the edges of the split body 12, the wire strands 17 are shaped in being interwoven so as to provide loops 24 through which may be threaded rods 25 defining the sides of the split. After the two parts 22 of the annulus are separated, the. open body 12 is placed around the cable and the'rods25 are brought together and secured by hooks 26.

The parts 22 of the annulus 10 are, according to the present invention, aligned and frictionally held together by pins 27, one on each part 22 engaging a hole 28 on the other part.

7 In order that the bodies 12 and 12a maynormally engage the cable under resilient contracting pressure (when the sides of the split are connected by the hooks 26), the body 12 and the body 12a as manufactured have diameters which are somewhat less than that of the cables with which they are to be used. Therefore, it is necessary, in order to wrap the body 12 around the cable and fasten it by the hooks 26, to apply force to the end 14 of the body and to the annulus to shorten the length of the body 12 and, as a consequence, increase its diameter. In the case of the tubular body 12a, the bottom end and'the annulus must be pushed together in order to permit the'cable to enter and pass through the body 12a. This can be done of course as an incident to the insertion of the cable in the body.

In installing the cable with theattachedcable grip in a conduit, considerable force must be applied to the annulus. Heretofore, this caused the portions of the strands 17 between the woven portion and the annulus to be pushed back through the holes 11 in'the annulus so that the loop portions 15 no longer engage the surface l6'of the annulus. After the annulus is seated onthe end of the conduit 18, force had to be applied to the projecting loops to push them down on the annulus, and

in doing this frequently some of the loops are distorted with the result that the pressure on the strands applied to the annulus is not equalized.

To prevent the portions 29 of the strands 17 between the loop portion and the woven portion from being pushed upwardly through the holes 11 under pressure, each pair of strands 17 is, according to the present invention, tightly twisted together as shown in FIGS. 1, 2, 3 and 5. This causes the twisted strands 31 to come together close to the bottom side of the annulus, so that the loops 15 are prevented from being lifted off the surface of the annulus.

Instead of twisting the wire strands as shown in FIGS. 1, 2, 3 and 5, the portions 29 between the woven portion and the annulus may be held together by rigid metal bands 30 as shown in FIG. 4.

I claim:

1. A cable grip having a load-bearing annulus; and an elongate open mesh body formed of diagonally woven wires depending from said annulus, each wire comprising a strand extending from the bottom of the body upwardly through a hole in said annulus and having a loop portion extending across and lying flat on the upper surface of said annulus and a strand extending downwardly from said loop portion through an adjacent hole in said annulus to the bottom of said body, the portions of said strands of each wire adjacent the underside of said annulus being tightly secured together to engage the underside of said annulus and prevent the strands from being pushed up through said holes when force is applied to said annulus and said body which would tend to cause said loop portions to be raised from the upper surface of said annulus.

2. A cable grip as defined in claim 1 in which said strands are secured together under said annulus by the portions of the strands adjacent said annulus being twisted together to cause the twisted portions of the strands to bind against the underside of the annulus.

3. A cable grip as defined in claim 1 in which said strands of wire are secured together under said annulus by collars secured tightly around the portions of said strands above the collars to bind against the underside of the annulus.

4. A cable grip as defined in claim 1 in which the body is split lengthwise and the annulus comprises two physically separate matching semicircular parts, each having one half the wire strands attached to it with the spaces between the parts aligned with the split of the body, means for connecting the parts together, and means for closing the split in the body.

5. A cable grip as defined in claim 4 in which the two parts of the annulus are aligned and held together by a pin on each part engaging a hole in the other part.

6. A cable grip as defined in claim 4 in which each part of said annulus has lugs depending from its underside and spaced inwardly from the periphery of said annulus to center the latter and the body in the riser with the peripheral margin of said annulus resting on the end of the riser, the two parts of said annulus being aligned and held together by a pin extending through one of said lugs on each of said parts engaging a hole in one of said lugs on the other part.

UNITED STATES PATENT OFFICE CERTIFECATE OF CORRECTEQN 3,599,913 Dated August 17, 1971 Patent No.

Inventor-(S) Joseph Di Palma It is certified that error appears in the above-identified patent and that said Letters ?atent are hereby corrected as shown below:

Claim 3, line 3, after "strands" insert adjacent said annulus to cause the portions of the strands Signed and sealed this lath day of March 1972.

(SEAL) Attest:

ROBERT GOTTSCHALK EDWARD M.FLETCHER,JR.

Commissioner of Patents Attesting Officer