US3070651A - Device for supporting or spacing cables - Google Patents

Description

1962 J. SEMPLE ETAL DEVICE FOR SUPPORTING OR SPACING CABLES Filed Aug. 24, 1961 fi/YD RoBERf GORDON Bnmn 22 BY: M1144,

United States Patetit C g I 3,070,651 DEVICE FOR SUPPORTING OR SPACING CABLES James Semple, Hamilton, Ontario, and Robert G. Baird,

Burlington, Ontario, Canada, assignors to N. Slater Company Limited, Hamilton, Ontario, Canada Filed Aug. 24, 1961, Ser. No. 133,657 Claims priority, application Canada June 12, 1961 2 Claims. (Cl. 174-128) This invention relates to an improved device for use in supporting or spacing a plurality of high tension cables in a predetermined parallel relationship to each other. When the power to be transmitted along any given transmission line is sufiiciently great to render it desirable to employ more than one conductor for each phase, it is customary to support these electrically common conductors from the towers ,or other fixed elevated structures by cradling such conductors in seats spaced apart from one another on a common suspension bracket, which bracket is then suspended from the lowermost insulator of a chain of insulators depending from the fixed structure.

Similarly, it is conventional to place cable spacers on the lines between the supporting towers of the transmission line to ensure maintenance. of substantially relative positioning of cables under all kinds of weather conditions. The basic considerations .of pre-determined spacing, of economies of time and etfort required in installation, of corona minimization and such aspects are common both to suspension brackets and cable spacers, so that whenever herein features are developed as applicable to suspension brackets by specific reference, the same is to be understood as equally applicable to cable spacers.

The object of the present invention is to provide an improved construction of devices of this type, and specifically to provide an improveddevice in which the need to position and then tighten individual bolt and nut assemblies to bring about the ultimate transmission cable gripping position is avoided. It is a further object that all involved manual manipulation is eliminated.

A further object is to provide a device having improved performance in respect to corona loss. The minimization of corona loss has become of increasing importance as the voltages of transmission have become higher and higher in recent years. It is known that corona loss can be reduced by designing the high tension parts with a minimum of sharp edges and corners, but nevertheless the design of suspension brackets and cable spacers has continued to include many such components as pins, bolts and nuts, all of which tend to provide sharp edges conducive to corona discharge. In contrast to this past practice, it is an object of the present invention to achieve a substantial reduction in the use of such parts.

Moreover, it is the further object of the present invention to achieve these improvements without sacrificing other performance features. In particular it is important to achieve and maintain a firm and uniform grip on each of the cables so that they cannot slide longitudinally within the support.

Moreover, it is the further object of the preferred form of the present invention to provide a device particularly suited for live line work through incorporating in the device the uniform and simultaneous movement of all transmission cable engaging surfaces, by coupling all of such surfaces by a linkage of the leverage type (that is one in which a mechanical advantage is obtained) that will, through one uncomplicated movement in a single straight line, bring all engaging surfaces uniformly into engagement and will, upon completion, ensure a substantial measure of pressure on the engaged surface of the cables, such pressure persisting upon completion of the engaging movement to ensure a firm and substantial hold on the cable. In the preferred construction this single 3,070,651 .Patented Dec. 25, 1962 movement of the device is a downward pull exerted at the centre of the linkage where a loop is provided. For live line work a long pole will enable manipulation of the device from below. This is believed to represent an improvement over suspension brackets and spacers that now exist, which call for a strong rotary movement of the components or a complex lifting and latching manipulation to bring the bracket or spacer into gripping position in engagement with the transmission cables, or the placing and tightening of a plurality of bolts and clamps or other time-absorbing practices.

' The manner in which these and related objects can be achieved is demonstrated by an embodiment of the invention that is illustrated in the accompanying drawings. This construction is shown by way of example and not by. way of limitation, since modifications and variations of the invention within the scope of the appended claims are. possible.

In the drawings:

FIGURE 1 is a front elevation view of a suspension bracket in open or cable-releasing position;

FIGURE 2 is a similar view of the bracket of FIGURE 1, but showing the parts in closed or cable-gripping position;

. FIGURE 3 is an enlarged fragmentary sectional view of a part of FIGURE 2; and I FIGURE 4 is a section on the line IV-IV of FIG- URE 2.

The figures show a suspension bracket composed of a base arm 10 which is of inverted U section and which serves to support pins 11 by which a pair of depending side arms 12 are pivotally connected to the base 'arm 10.

Near their lower ends the side arms 12 each carry a pin 13 mounting one end of a link 14, the other end of which is articulated by means of a pin 15 to a further link 16.

The two links 16 are pivotally connected together by a further pin 17, each such link including a semicircular segment 18 having an arcuate slot 19 described about the centre of the pin 17. The open end of the U-shaped structure defined by side arms 12 and upper arm 10 is thus closed by links 14, 16. The two segments 18 lie face-toface against one another and preferably at least one has serrations 20 formed on its face engaging the other segment to further inhibit relative movement between such segments when a bolt and nut clamping assembly 21 extending through the slots 19 is tightened. When the assembly 21 is loosened, the pin 17 allows sufficient freedom for the serrations 20 not to prevent the links 16 swinging about such pin. A ridge 29 acts as a nut keeper for the nut of assembly 21. This ridge prevents the nut turning when the bolt is rotated, and inasmuch as the bolt is reversible the ridge has been provided on both sides.

Four cable-clamping assemblies 22 are provided, each assembly being formed of two jaws. The respective jaws of each assembly are mounted on arms 10 and 12, and links 14, so as to be movable between the open, cablereleasing position of FIGURE 1 and the closed, cablegripping position of FIGURES 2 to 4, upon corresponding movement of the toggle mechanism constituted by the links 14 and 16 from the collapsed condition of FIGURE 1 to the extended condition of FIGURE 2. FIGURE 1 shows the bracket suspended from a pair of upper cables 23, while the lower cables 23 are supported in the lower parts of the lower assemblies 22. All four clamping assemblies are then simultaneously closed and adequate gripping pressure applied to the cables 23 by the toggle leverage action obtained when links 16 are pulled down. The linkage is then held firmly in place by the single bolt assembly 21 which can be readily tightened (or loosened) by live line tools. The convenience of assembly and disassembly will be readily apparent.

This single action cable gripping effect is obtained by virtue of the frame of the device with its cable clam-ping jaws integrated in a leverage system, in which a mechanical advantage is obtained as between the closing force and the forces exerted by the jaws on the cable. In this connection integrated carries the conception of an asasembly in which every component is subject to and part of a leverage system, .and in movement to the ultimate installation position every element or component part is controlled and dependent in any movement it may make by the co-ordinated movement of the body of the other elements or component parts that make up the frame of thedevice, as distinguished from a device in which only part or one of the elements making up the frame may be controlled in its course of installation to the ultimate gripping position by inter-dependent leverage action.

Cable supporting devices of a free linkage type, or of a cam and lever type, have been previously proposed, but in such construction they have failed to accomplish at one and the same time a simultaneous leverage action, directing and controlling the movement of each component to an ultimate installation position, where positive equalized leverage gripping action is exerted at the cable clamping jaws. They have also failed to simplify the movement of installation to a single downward pull action that can be readily accomplished with an extended live line tool.

FIGURE 3 shows one of the cable-clamping assemblies 22 on a larger scale, and in central section. The partially cylindrical members 24, 25 that form the jaws of the assembly are each provided with a corresponding semicylindrical insert 26, 27 made of rubber or other material having suitable resiliency. These inserts are designed to inhibit longitudinal slippage of the cables and are not intended as electrical insulation. In fact, like the remainder of the device, they will preferably be made of electrically conducting material or will include an electrical conductor, to minimize radio and television interference noise levels, since the four cables will be electrically common. When used as a suspension bracket, the entire device will be insulated from the other conductors by suitable means (not shown), such as a chain of depending insulators to which the bracket is connected by a bolt to pass through a hole 28 in the upper arm 10. When the device is em played as a spacer, the hole 28 may be omitted.

erally parallel to each other and both pivotally connected to a base arm to form a generally U-shaped structure, jaws disposed on said elements in a plurality of pairs so that each pair defines a cable-clamping assembly, said leverage system being movable from an open position in which the jaws of each cable-clamping assembly are open for insertion or removal of a cable to a closed position in which the jaws of each cable-clamping assembly are forced together to exert gripping pressure on a cable between said jaws, said leverage system including a toggle mechanism movable from a collapsed angular position to a closed linearly extended position to bring said linkage to said closed position and force said jaws together, said cable-clamping assembly being disposed at each corner of the structure formed by said arms and toggle mechanism, said toggle mechanism interconnecting the free ends of said arms for forcing said arms apart to an extended position of said mechanism, said toggle mechanism including a pair of pivotally connected links, and means for securing said toggle links together to prevent relative pivotal movement, the device being in a normally closed position when the toggle mechanism is in an extended straight condition, and in a normally open position when said mechanism is in a collapsed condition.

2. A device according to claim 1 wherein each of said jaws includes an insert of resilient material positioned for gripping engagement with a cable.

References Cited in the file of this patent UNITED STATES PATENTS 241,650 Hamilton May 17, 1881 496,104 Svensson Apr. 25, 1893 1,751,827 Marshall Mar. 25, 1930 1,918,486 Onos July 18, 1933 2,106,373 Garriott Jan. 25, 1938 2,912,482 Horrocks et al Nov. 10, 1959 2,928,636 Flower Mar. 15, 1960 2,976,344 Bethel Mar. 2 1, 1961

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