US3380693A

US3380693A - Cable clamp with means for distributing the cable load between the clamping jaw and the clamp body

Info

Publication number: US3380693A
Application number: US602999A
Authority: US
Inventors: L E Lindsey
Original assignee: L.E. Lindsey
Current assignee: L E LINDSEY
Priority date: 1966-12-19
Filing date: 1966-12-19
Publication date: 1968-04-30
Anticipated expiration: 1985-04-30

Description

April 30, 1968 3,380,693 FOR DISTRIBUTING THE; CABLE LOAD BETWEEN THE CLAMPING JAW THE CLAMP BODY Filed Dec. 19, 66

/Z 5;; Zfl "30 25 4/ F a 1X0 AZ 25 a5 I Z fa g} /41 Z4Z5 /a k A E. m Z0 /d United States Patent ABSTRACT OF THE DTSCLOSTURE This invention relates to cable clamps and more particularly to an improved cable clamp suitable for use in supporting one or more power transmission cables in suspension from the lower end of a high tension insulator. The clamping jaw for each cable and the main body of the clamp have interfitting complementary lug and recess means positioned to iaternest and effective to distribute the load stresses between the jaw and the main body of the clamp. The interfitting parts provided for this purpose are positioned adjacent the upper side of the cable and each clamping jaw is connected to the main body by a horizontally disposed hinge pin crosswise of the lower end of the jaw.

It is highly important that suspension clamps used in supporting power cables, as well as general duty cables, provide maximum strength with a minimum of material. Prior clamp designs have failed to meet this objective satisfactorily with the result that excessive quantities of material have been required to form the main body of the clamp in order to meet strength requirements with an acceptable safety factor. This is because the clamping member cooperating with the main body to secure the cables in position have been so designed as to be incapable of assuming a portion of the load with certainty and reliability. It follows that the main body must be de signed to carry the full load.

According to the present invention the foregoing and other shortcomings of prior clamp designs has been avoided with the result that there is provided a superior high strength low weight clamp assembly. These ends are achieved by designing the main body and the juxtaposed upper edge of the clamping jaw that these parts internest and interlock with one another to the requisite extent to enable the jaw member to carry its proportionate share of the load along with the main body of the clamp. Typically, the mating upper edge of the jaw and the main body have lugs and recesses aligned to mate as the jaw closes with the result that a major portion of the cable load is carried by the clamp itself and another portion by the main body. In this manner, full advantage is taken of the material present in the clamping jaw and the load imposed by the cable is distributed and shared equitably by the clamp and by the main body so long as the jaw is held closed by tightening of any suitbale fastener means associated with the free end of the clamping jaw. Upon loosening the fastener means, the intcrnesting parts of the jaw and main body separate from one another as the jaw swings open to a position for releasing or receiving a cable.

The principles of this invention can be employed in a clamp assembly having provision for either single or multiple cables. In the latter event, the number of clamping jaws is increased to provide a separate jaw for each cable all hingedly associated with a common main body and the cable seating recesses being suitably spaced to meet the needs of a particular operating environment.

It is therefore a primary object of the present invention to provide an improved single or multiple cable clamping assembly having maximum strength and mini- 3,380,6Q3 Patented Apr. 30, 1968 'ice mum weight and featuring a simple rugged arrangement wherein the main body and the individual clamping jaws cooperate in sharing the cable load equitably.

Another object of the invention is the provision of a bundling clamp assembly for use on high tension power lines featuring a unitary main body and a plurality of independent clamping jaws each designed upon being closed to share a proportionate share of the cable load along with the main body of the clamp assembly.

Another object of the invention is the provision of a high-efficiency, low weight, high strength bundling clamp for use on high tension power lines and utilizing separate downwardly opening cable clamping jaws having their free edges contoured to mate and interlock with complementally shaped portions of the main body in such manner as to distribute the load of the cable equitably between the main body and the clamp jaw itself.

These and other more specific objects will appear upon reading the following specification and claims and upon considering in connection therewith the attached drawing to which they relate.

Referring now to the drawing in which a preferred embodiment of the invention is illustrated.

FIGURE 1 is a side elevational view of a preferred embodiment of the invention shown assembled and in use to support a pair of power conductors by suspension from an insulator;

FIGURE 2 is a fragmentary cross-sectional view on an enlarged scale taken along line 22 on FIGURE 1; and

FIGURE 3 is a cross-sectional view taken along line 3--3 on FIGURE 2.

Referring more particularly to FIGURE 1, there is shown a bundling cable clamp, designated generally 10, made in accordance with the principles of the present invention and shown suspended from the lower end of a typical high tension insulator l1. Bundling clamp It is there illustrated as supporting two

power cables

12, 12 in vertical alignment with one another. However, it will be understood that numerous other arrangements including provision for three or more cables may be employed by suitable modifications in the contour of the main body of the clamp assembly.

As is more clearly illustrated in FIGURES 2 and 3, the bundling clamp assembly includes a main body 14. of an appropriate contour. This body is provided at its upper end with a clevis l5 straddling a connection sh ank 16 projecting downwardly from insulator 11 and pivotally connected thereto by :a bolt 17. The opposite or lower end of the main body includes a loop 18 useful for various purposes including the support of anti-sway weights, not shown, but well known to those skilled in the design and operation of power transmission lines.

As herein shown, bundling clamp 10' is formed with a pair of vertically spaced venturi shaped cable seating pass-ages 20 having the general configuration best shown in FIGURE 3. The throat 21 of these passages is preferably slightly smaller than the diameter of the cable being clamped in order to grip the cable firmly when its clamping jaw is substantially fully closed. The venturi shaped cable seating and clamping passages are formed partly within main body M and partly within the associated clamping jaw 23.

Jaws 23 have the general configuration shown in FIG- URES 1 and 2 and are pivotally connected to the main body at their lower end by a hinge pin 24. This pin is preferably held in its assembled position by one or more retainer pins 25 disposed, as shown in FIGURES 2 and 3, and passes through rib 26 projecting laterally transversely of the exterior of each clamping jaw as is clearly shown in the drawing. The laterally projecting and flaring opposite ends of each clamping jaw project beyond main body ribs 28 and their lower edges engage ribs 23 to limit the downward pivotal movement of the jaws 23 when open. he open position of the jaws is indicated in dotted line in FIGURE 2. It will therefore be appreciated that when the jaw is open the interior arcuate recess or surface 3t? faces upwardly so that the jaw provides a shelf on which the cable rests temporarily while being shifted into its final seating position. While so supported on the open jaw, the cable is readily shifted into its fully assembled position by upward pivotal movement of the jaw.

An important feature of the invention will now be described with the aid of FIGURES 2 and 3. As there shown, the inner edge of the free end of each clamping jaw is formed with one or more recesses 32 for receiving and snugly seating complementally shaped lugs 33 projecting thereinto from main body 14. These lugs telescope into the recesses as the clamping jaw 23 is pivoted to its closed position against the cable. Threaded cap screws 35 pass freely through bores 36 in the upper edges of the clamping jaws and engage with threaded bores 37 in the main body of the clamp. Split spring lock keepers 3v serve to hold the cap screws against loosening.

From the foregoing and particularly from a consideration of FIGURE 2, it will be apparent that a cable seated within either of the clamping recesses 24 will be sup ported in part by the main body and in part by the clamping jaw. The weight acting downwardly on the interior lower side 40 of the clamping jaw will be transmitted upwardly along the jaw and will be transferred to the main body of the clamp via the engaging surfaces of recess 32 and the juxtaposed upwardly facing surfaces of lugs 33. Other portions of the cable weight will be transferred to the lower interior surface 41 of the main body and will be transmitted to the insulator by the main body and clevis 15. A portion of the cable weight may also be transmitted to the main body through hinge pin 24. Another portion is transmitted between the parts by cap screw 35. It will be apparent that the cable load is equitably distributed throughout all portions of the clamping assembly '10 with the result that very substantial savings in the amount and weight of the material used in forming assembly may be realized without sacrificing the load carrying ability of the structure and the safety factor employed in its design and construction.

While the particular cable clamp herein shown and disclosed in detail is fully capable of attaining the objects and providing the advantages hereinbefore stated, it is to be understood that it is merely illustrative of the presently preferred embodiments of the invention and that no limitations are intended to the details of construction or design herein shown other than as defined in the appended claim.

I claim:

1. A clamp for use in suspending a cable below the lower end of a suspension type insulator, said clamp having a main body provided with means at its upper end for securing the same to the lower end of a suspension insulator for suspension therebelow, one transverse face of said main body having a semi-circular cable seating recess extending horizontally thereacross with the open face thereof lying generally vertically, a cable clamping jaw for said cable seating recess having a semi-circular cable seating recess facing toward and cooperating with said cable seating recess to clamp a cable in place therebetween, horizontally disposed hinge pin means extending through the lower edge of said clamping jaw and the adjacent portion of said main body to hold said jaw pivotally assembled to said main body for movement between a closed position and an open position generally degrees from said closed position, the upper edg of said clamping jaw being designed to lie parallel and substantially against the juxtaposed surfaces of said main body in the closed position of said jaw, clamping screw means extending through the upper edge of said clamping jaw and into said main body, pairs of lugs and complementally shaped recess means facing toward one another from said main body and from the upper edge of said claim:- ing jaw and disposed to either lateral side of said clamping screw means and positioned to mate as said jaw is closed, and each pair of said lugs and recesses having elongated upper surfaces of substantial horizontal width disposed to lie in load bearing contact with one another irrespective of whether said lugs and recesses are fully or only partially mated and cooperating to distribute the load of a cable seated in said cable seating passage equitably between the clamping jaw and the associated portion of said main body while avoiding placing excessive strain on the clamping screw means.

References Cited UNITED STATES PATENTS 471,096 3/1892 Briggs 248-63 X 824,544 6/1906 Hossege 24858 1,630,423 5/1927 Gothberg 174-169 X 2,122,988 7/1938 Nelson 24858 X 3,155,354 11/1964 Lindsey 24863 LARAMIE E. ASKIN, Primary Examiner.