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Publication numberUS3761865 A
Publication typeGrant
Publication dateSep 25, 1973
Filing dateJun 8, 1972
Priority dateJun 8, 1972
Publication numberUS 3761865 A, US 3761865A, US-A-3761865, US3761865 A, US3761865A
InventorsBomgaars G
Original AssigneeVeldhuizen Arlo B Van
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Safety device for cables supporting electrical wires
US 3761865 A
Abstract
A breakaway connector is attached to a pole to release a cable supporting electrical wires extending to a building, upon excessive pull on the cable, caused by high winds, ice accumulation, accident or the like. A disconnect is provided in each of the electrical wires adjacent the pole, so that the wires will be disconnected, when the cable is released, thereby preventing charged electrical wires from lying on the ground. The breakaway connector includes a pivotal detent bar which is longitudinally shiftable towards the cable against the bias of a relatively heavy compression spring. The cable is connected to the detent bar by a ring looped over an upright portion of the bar. Cable tension on the ring tends to both rotate and longitudinally shift the bar. Under normal cable load conditions, the bar engages stop means to prevent its rotation; however, excessive pull on the cable longitudinally shifts the bar away from the stop means to allow its rotation which, in turn, releases the ring and cable from the detent bar. Each disconnect for a wire includes a female clip having a socket and a male clip having a stub which is split longitudinally and is provided with pipe threads, on the inside, while an Allen screw for adjustment along the threads adjusts the friction fit between the stub and the socket. A plastic cover which extends beyond each clip and protects the connection from weather is attached to the female clip, so that it will remain with the female clip, when the clips separate. This prevents a short between the female clips of several disconnected wires, after separation.
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Description  (OCR text may contain errors)

United States Patent 9 11 1 Bomgaars et a1. v

[ SAFETY DEVICE FOR CABLES SUPPORTING ELECTRICAL WIRES [76] Inventors: Galen D. Bomgaars, 1785 S. Bryant St., Denver, Colo. 80219; Arlo B. Van Veldhuizen, Rt; 1, Box 199, Hull, Iowa 51239 [22] Filed: June 8 1972 [21] Appl. No.1 260,889

Related [1.8. Application Data [63] Continuation-in-part of Ser. No. 61 ,877, Aug. 7, I970,

Primary Examiner-1oseph l-l. McGlynn Attorney-Horace B. Van Valkenburgh 1451 Sept. 25, 1973 [57] ABSTRACT A breakaway connector is attached to a pole to release a cable supporting electrical wires extending to a building, upon excessive pull on the cable, caused by high winds, ice accumulation, accident or the like. A disconnect is provided in each of the electrical wires adjacent the pole, so that the wires will be disconnected, when the cable is released, thereby preventing charged electrical wires from lying on the ground. The breakaway connector includes a pivotal detent bar which is longitudinally shiftable towards the cable against the bias of a relatively heavy compression spring. The cable is connected to the detent bar by a ring looped over an upright portion of the bar. Cable tension on the ring tends to both rotate and longitudinally shift the bar. Under normal cable load conditions, the bar engages stop means to prevent its rotation; however, excessive pull on the cable longitudinally shifts the bar away from the stop means to allow its rotation which, in turn, releases the ring and cable from the detent bar. Each disconnect for a wire includes a female clip having a socket and a male cliphaving a stub which is split longitudinally and is provided with pipe threads, on the inside, while an Allen screw for adjustment along the threads adjusts the friction fit between the stub and the socket. A plastic cover which extends beyond each clip and protects the connection from weather is attached to the female clip, so that it will remain with the female clip, when the clips separate. This prevents a short between the female clips of several disconnected wires, after separation.

18 Claims, 20 Drawing Figures Patented Sept. 25, 1973 3,761,865

3 Sheets-Sheet l INVENTORS Galen D. Bomgaars' Arlo B. Van Veldhuizen ATTORNEYS 'Patented Sept. 25, 1973 3 Sheets-Sheet 2 m m 0 w s mm N W .18 w 0% 3 G V FWM A V 5 O 5 M 0 H Q 0 5 l ATTORNEYS Patented Sept. 25, 1973 s Sheets-sheaf 5 Fig.

SAFETY DEVICE FOR CABLES SUPPORTING ELECTRICAL WIRES This application is a continuation-in-part of our copending application Ser. No. 61,877, filed Aug. 7, 1970, now abandoned.

The present invention relates to a safety device for cables for supporting electrical wires, which will release such a cable in case of an emergency. As such, the invention will be hereinafter referred to as a breakaway connector for a suspension cable, or simply as a breakaway connector.

The invention may be used for a number of different applications where a cable and other members supported by it are to be released when under excess tension. However, the most common use of the invention resides in providing a breakaway connector for a suspension cable which supports the electrical service wires extending from a power line pole to a building. Very often, the span between the utility pole and the building will be fifty feet or more, and a common practice is to wrap the insulated electrical service wires about a metal suspension cable which supports the wires in the span between the pole and the building. The metal cable is strong enough to support the load to which it is normally subjected, but occasionally, a strong wind will cause the cable to whip violently or an accumulation of sleet ice, or an accident, will pull the cable from its anchor point at the building, or perhaps break the cable nearer the building than the pole. Such an accident wll also break the electrical wires supported by the cable, and create a severe ground danger due to charged electrical wires on the ground, with attendant danger to anyone who may come in contact with them. Such .a danger may sometimes be diminished by the wires shorting out to the ground, but at the expense of creating an overload on the power supply lines and tripping circuit breakers at the next power sub-station.

There is a real and definite need for an improved safety device for suspension cables which support the electrical service wires extending between a pole and a building, and the present invention was conceived and developed with such a need in view. The invention comprises in essence: first, a breakaway connector which holds the suspension cable but which is adapted to release the cable at the pole whenever an excessive strain is applied to the cable; and secondly, a disconnect for each electrical wire supported by the cable, located on the wire adjacent to the breakaway connector to permit the electrical wires to separate at the pole whenever the connector releases the cable.

It follows that an object of the present invention is to provide a novel and improved breakaway connector for a suspension cable, which will normally hold the suspension cable, but which will disconnect at the pole or similar support, should an excessive pull on the cable occur.

Another object of the invention is to provide an improved combination of a breakaway connector for a suspension cable and disconnects for the electrical service wires supported by the cable, which are also located at the pole, to permit a simultaneous separation of the electrical wires whenever the breakaway connector releases the cable, thereby to eliminate the hazards of charged electrical wires on the ground and minimize damage to the operation of the system.

Another object of the invention is to provide a novel and improved breakaway connector for a suspension cable and disconnects for the wires supported by the cable which constitute a simple but reliable system for protecting the power leads extending from a pole to a building.

Another object of the invention is to provide a novel and improved breakaway connector for a suspension cable to which the cable is readily attached.

Another object of the invention is to provide a novel and improved breakaway connector for a suspension cable and disconnects for the service Wires supported by the cable which provide a quick and easy mode of removing the cable and wires from an electrical pole when construction activities, repairs, or the like neces' sitate such removal.

Another object of the invention is to provide a breakaway connector for a suspension cable and electrical wire disconnects which are simple, economical, easily installed, reliable and durable units.

Another object of the invention is to provide a novel and improved breakaway connector for a suspension cable which is adapted to be easily and economically manufactured by conventional methods for commercial purposes.

With the foregoing and other objects in view, our invention comprises certain constructions, combinations and arrangements of parts and elements as hereinafter described and illustrated in preferred embodiment in the accompanying drawings, in which:

FIG. l is a perspective view of the upper portion of a power-line pole having electrical service wires extending from one side thereof, as to a building or the like, with the service wires being supported upon a suspension cable, with one embodiment of the improved breakaway connector connecting this cable to the pole and with disconnects on the service wires adjacent to the pole, all in accordance with the present invention;

FIG. 2 is a fragmentary side elevation, on a larger scale, of the breakaway connector of FIG. l, as secured to the pole and holding the suspension cable;

FIG. 3 is a side elevation similar to FIG. 2, but showing the manner in which a breakaway action commences when the cable is subjected to an excessive pull and showing further, in broken lines, the movement of certain components of the breakaway connector as the cable is completely separated from the pole;

FIG. 4 is a side elevation similar to FIG. 2, but on a further enlarged scale and with portions of certain components being broken away or in longitudinal section to show parts otherwise hidden from view;

FIG. 5 is a fragmentary, top plan view, showing the front portion of the connector as in FIG. 4 and illustrating specifically the construction of a release link by which the cable is attached to the connector;

FIG. 6 is a fragmentary sectional detail, taken along line 6-6 of FIG. 5 but on an enlarged scale;

FIG/7 is a front end view of the connector, on the same scale as FIG. 6;

FIG. 8 is a fragmentary sectional detail of a detent bar of the connector, taken along line 8-8 of FIG. 6 but on an enlarged scale;

FIG. 9 is a side elevation of the upper portion of a modified detent bar;

FIG. 10 is a side view of the female portion of a disconnect for an electrical service wire, particularly 3 adapted for use in the present invention and showing the same as being crimped onto the wire.

FIG. 11 is a side view of the male portion of the disconnect for an electrical service wire and showing the same as being crimped onto the wire;

FIG. 12 is a longitudinal section of the female disconnect portion of FIG. 10, shown as prior to attachment to an electrical wire;

FIG. 13 is a longitudinal section of the'male disconnect portion of FIG. 11, shown as prior to attachment to an electrical wire;

FIG. 14 is a side view of the disconnect portions of FIGS. and 11 when interengaged and within a protective sheath, the latter being shown in section; 1

FIG. 15 is a side elevational view similar to FIG. 2, but showing another embodiment of the breakaway connector, and'showing further, in broken lines, the

movement of certain components as the cable is completely separated from the pole;

FIG. 16 is a top plan view of the connector of FIG. 15, but with portions of a link or ring which normally connects the cable to the connector, broken away to show underlying components otherwise hidden from view;

FIG. 17 is an offset longitudinal section of the connector, taken along line 17-17 of FIG. 16 but on an enlarged scale;

FIG. 18 is a transverse section of the connector, taken along line 18-18 of FIG. 17;

FIG. 19 is an isometric view of one of a spring retainer plate of the connector, but on a reduced scale; and

FIG. 20' is a side elevation of one of the L-shaped arms which pivotally carry a detent bar of the connector, but on a reduced scale.

Referring more particularly to the drawings, a typical environment for the present invention is illustrated in FIG. 1, in which a power line pole P supports electrical power lines 10 attached to insulators on a cross arm 11 in a conventional manner. Pigtails 12 from the power lines extend to a transformer 13, from which electrical service wires 15 normally extend laterally from the pole to an installation, such as a building, not shown. The electrical service wires 15 are ordinarily comparatively heavy copper wires with a heavy, weatherproof insulation and should the span from the pole to their remote connection at a building or the like be of any distance, these wires are carried by and wound upon a metal wire suspension cable C. The wire cable C is commonly anchored to the upper portion of the pole, as at an eyebolt l6, and secured to the remote building or other structure by a similar type of anchor. Sometimes, the load on the suspension cable becomes far greater than the dead weight of the electrical wires and even to'the point where the cable pulls out one of its anchors. This may occur by the whipping action of a strong wind, by accumulation of sleet ice or even by an accident, such as by the boom of a crane being unintensionally swung into the wire.

Referring first to FIGS. 1-14 of the drawings, one embodiment is a breakaway connector B connected between cable C'and the pole P, as by a short cable 17 connected to an eyebolt 16 on the pole, in order to separate the cable from the pole, should the cable be pulled with an excessive force. Also, disconnects D are installed between pigtails 18, leading from the transformer T, and the'service wires 15 adjacent to the breakaway connector, to permit the wires also to be separated adjacent the pole P, whenever the cable C is separated from the pole. By locating the breakaway connector B and the wire disconnects D adjacent to the power line pole, at a normally relatively high elevation from the ground, the cable and the wires will fall away from the pole and no electrical complications, such as hot wires lying upon the ground or short circuits, will be possible. Moreover, the cable C and the wires 15 can be subsequently reconnected in a quick, easy manner.

The breakaway connector B, as illustrated in FIGS. 2 through 5, includes an elongated, tubular body 20 having an end wall 21 and an axially centered rod 22 within it, the rod forming a shifting member. One end of rod 22 projects from the body, through a central hole in end wall 21, as in FIG. 4, and a detent bar 23 is pivotally mounted, as at its upper end, upon this projected end. The detent bar 23 normally engages but is disengageable from a preferably trapezoidally shaped link or ring 24 which, in turn, is secured to the cable C. A trigger pin 25 is carried by the opposite end of detent bar 23 and is normally restrained to longitudinal movemerit within a tubular sheath 26 which is connected to and parallels the body tube 20. Whenever the rod 22 is pulled, against the pressure of a spring 27, from the body a critical distance, such as that indicated as d in FIG. 3, the trigger pin will be released from its sheath to permit the detent bar 23 to swing about rod 22, as to the full and then the dotted position of FIG. 3, to separate from the link 24 and thereby disconnect the cable from the pole.

The inner end 28 of rod 22 is threaded to carry a washer 29 slidably fitted within the body tube 20 and adjustably secured to the end of the tube by a nut 30, for which a lock nut (not shown) may be provided. Compression spring 27, within body 20, bears between the end wall 21 and the washer 29 to bias and urge the rod 22 inwardly into the body. Preferably, spring 27 is comparatively stiff, having a stiffness such that it can withstand the normal pull of the suspension cable C, without any significant deflection until the pull on the cable approaches an excessive force. The end of the tube 20, opposite the closed end 21, is preferably open to permit a mechanic to easily reach the nut 30 and by turning the nut on the threads of rod end 28, easily adjust the force of the spring 27 to make the spring force strong enough to prevent any unintentional separation of the breakaway connector after it is installed.

The detent bar 23, as in FIGS. 4 and 6, has a forked upper end which forms a yoke 32 to embrace the end of rod 22, being held thereto by a pivot pin 33, as in FIG. 7. This detent bar is normally positioned perpendicularly to the rod 22 and is provided with a seat or notch 34 adjacent to the yoke wherein the link 24 is received. The opposite end of the detent bar has a threaded passage 35 to receive the threaded end 36 of trigger pin 25, which will lie parallel to the rod 22 when the detent bar 23 is perpendicular to the rod and is maintained in adjusted position by a nut 37. A flat 38 on opposite sides of the outer end of pin 25 facilitates tuming'with a wrench, for adjustment.

The link or ring 24, as in FIG. 5, is formed of wire or rod as, a trapezoidal, closed loop having a wider end provided with a-spreader 39 attached to the cable C and a narrower end 40 fitted in the seat or notch 34. The sides of the link are sufficiently long to permit the detent bar 23 and the trigger pin 25 to easily swing through the link whenever the trigger is released, as illustrated in FIG. 3, the spreader 39 holding the sides of the link apart to prevent the detent bar from accidentally fouling or hanging up on the link when the detent bar is pivoting for disengagement from the link. In FIGS. 6 and 8 is shown one form of the notch 34 for engaging the link, having a generally arcuate inner edge and corresponding in depth to the diameter of the wire or rod of link 24. Another form of notch 34', shown in FIG. 9, is elongated, but appears in central section as similar to notch 34 in FIG. 8, and may be used to permit the link to more easily slide away from the detent.

The portion of trigger pin 25 which extends into sheath 26 is formed as a smooth rod for movement in a central hole in the closed end 41 of the sheath, with the hole having a guide lip 42. The opposite end of the sheath preferably also is closed to prevent debris or the like from accumulating within the sheath. In this connection, it will be noted that movement of washer 29 in body 20 will tend to push debris therefrom. Sheath 26 may be attached, as by welding, directly to body 20 but is more conveniently attached thereto by a bar 44,

which is more readily welded to the sheath and body and also provides a location for a hole 45, by which cable 17 may be attached to the connector in a position which minimizes interference with access to nut 30 of FIG. 4, for adjusting the force of spring 27.

It follows that, in the operation of the breakaway connector B, the cable 17 is held by the closed connector to the pole P. The nut 30 may be used to increase the force of spring 27, after the cable and breakaway are positioned, so that the cable will be taut under normal conditions. The trigger pin 25 is of a length such that the inner end thereof will be pulled from sheath 26 when the detent bar, is subjected to a predetermined pull by the cable, so that the cablewill remain connected to the pole during normal adverse weather conditions, but the connector will release the cable before the anchor at the opposite end of the cable will be pulled out.

It is necessary that the electrical service wires 15, which are wrapped about and supported by the cable, be also separated whenever the cable separates from the pole, to prevent them from being pulled apart. Accordingly, a disconnect C is provided in each electrical wire supported by the cable and the disconnect must be adjacent to the breakaway connector, to achieve the desired results. Thus a conventional electrical plug may be provided for this purpose. However, conventional plugs are not always suitable for exposure such as encountered by the wires which are completely unprotected by the weather. A preferred type of disconnect D of this invention is shown in FIGS. through 14. The disconnect D consists essentially of two portions: a tubular, female clip F for a pigtail 18 extending from the transformer, and an opposing, tubular male clip M for the end of the wire extending away from the disconnect and to a building or the like.

Each clip F and M is formed of cylindrical stock, as of brass or other metal, sufficiently malleable as to be crimped onto the wire to remain tightly connected thereto, as by a crimp 50, and each has the same outside diameter. A hole 51 is drilled into the outer end of each clip and has a diameter sufficient to snugly receive the end of the wire from which the insulation 52 has been removed. However, other modes of connecting the wires, such as by soldering, are also possible.

The inner end of the female clip F is provided with a socket 53, as in FIG. 12, to receive a corresponding stub 54 on the inner end of the male clip, as in FIG. 13. A snug fit, such that the two clips will sustain a moderate amount of force before separating, is desirable. In order to attain such a fit, the stub 54 has opposed longitudinal slits'55, whie an while threaded longitudinal socket 56 within the stub receives an Allen screw 57. The threads in the socket 56 may be slightly tapered, as in the manner of pipe threads, with corresponding threads on the set screw, so that the cap screw 57 may be located in any selected position, but will spread the stub at each side of the slots a distance sufficient to attain the desirable tight, sliding fit in the socket.

After the male and female clips are attached to the respective wires, an insulating sheath may be placedabout the disconnect, in order to prevent it from being exposed to the elements and to prevent a clip of one wire from striking a clip of another wire, after disengagement of the three disconnects shown, causing a .short. A tubular sheath 60 of a weather resistant insulating plastic, such as polyurethane plastic or rubber, is accordingly fitted about the clips and is attached to the female clip, so that it will still cover the end of the female clip after the male clip separates therefrom. For this purpose, a groove 61 may be provided on the outside of the female clip, as in FIGS. 10 and 12, so that a small flame may be applied to the sheath, around its periphery at the groove, to cause the sheath to skrink into the groove, as at 62 in FIG. 14. This will hold the sheath in place, with one end overlying the wire extending from clip F and the other end overlying the wire extending from clip M. It follows that, since the female clip F of the disconnect is connected to the wire 18 extending from the transformer, should the disconnect be pulled apart, the sheath 60 will remain with the female clip to shield the same against accidentally striking the female clip of another wire, a piece of metal on the pole, or the like, to Cause a short circuit of the main wires of the system. This exposes the male clip M whenever the disconnects separate, but whenever separation occurs, there will no longer be a charge in the wire 15 and no danger of a short circuit or an exposed, charged electrical wire, will exist.

As indicated previously, the cable C is readily attached to the breakaway connector, as by loosening nut 30 of FIG. 4, so that the rod 22 may be more readily pulled outwardly from the body 20 and the pin 25 thus separated from the sheath 26. The detent bar 23 is then inserted in the ring 24, as to the full position of FIG. 3, and the pin 25 replaced in sheath 26. Then, the nut 30 may be tightened, to provide sufficient tension on the cable C to prevent release during normal conditions. For such attachment, the end of cable C may be pulled to a position adjacent the connector, as by attaching a rope, cable or corresponding part of a pulling device to the end of cable C adjacent ring 24, and the cable pulled into position by a rope and pulley, block and tackle, or any other suitable conventional device useful for that purpose. The opposite end of the pulling device is conveniently attached to the pole P, with the device being removed after the nut 30 has been tightened. The pin 25 may also be adjusted, as by loosening nut 37 and advancing or retracting the threaded portion 36 of rod 25 within the threaded hole in detent bar 23, so that the pin will be released from the sheath 26 only when the tension on the cable C is excessive, i.e., such that the anchor or anchors for the cable would be pulled out. A similar procedure is used in reattaching the cable C to the breakaway connector B, after the cable has been released, due to storm conditions, high winds, accident or the like, with any damage to the wires 15 carried by the cable being repaired prior to such installation. When it is desired to remove the cable C from the breakaway connector deliberately, as for one or more of the reasons hereinbefore specified, the nut 30 is loosened until the normal tension on the cable pulls the rod 22 outwardly a sufficient distance to release pin 25 from sheath 26. If desired, a tension device may be connected between the end of the cable C and the pole P, so as to lower the cable to the ground, rather than permitting the cable to be released suddenly from the connector, with the possibility of striking a workman in the immediate area. It will be understood, of course, that the cable may be installed or deliberately released in any other desired manner, such as by use ofa special clamp which pushes rod 22 out of the body until the pin 25 is released or may be used to compress the spring 27. Such a device may be loosened to release the pressure on the spring, after the pin 25 has been inserted in position, in originally installing or replacing the cable connection with the breakaway connector.

The embodiment illustrated in FIGS. 1520 is a simplified arrangement of components forming an improved breakaway connector B, designed to be easily and economically manufactured for commercial purposes, as well as to be a highly reliable and dependable cable safety release device. Connector B is suspended between a utility pole P and a cable C to connect the cable to the pole under normal conditions, but to release the cable from the pole when the cable is subjected to an excessive load, in a manner similar to connector 13, previously described. Connector B is essentially a box-like structure formed by two interlocking and opposing U-shaped yokes Y and Y of heavy gauge sheet metal, or the like. The side and rear walls of the box are formed, respectively, by arms 65 and base 66 of front, pole facing yoke Y, with base 66 being shown in FIG. 17, while the top, bottom and front walls of the box are formed by arms 67 and base 68, respectively, of cable facing yoke Y. The upper and lower arms 67 of cable facing yoke Y overlap base 66 of yoke Y, while side arms 65 of yoke Y overlap base 68 of yoke Y. The yokes slidably engage each other and the bases 66 and 68 thereof, as in FIG. 16, are separated by a compression spring 69. Thus, a pull on cable C tends to move rear yoke Y over from yoke Y, thereby compressing spring 69. Spring 69 may be a heavier or lighter spring, or may be greater or lesser in outer diameter, depending on the installation and the force to be resisted. As in FIG. 17, to maintain the spring in position, each opposite end of the spring surrounds a button 70 which is attached, as by spot welding, to a rectangular plate 71 which fits against base 66 and base 68, respectively. Each plate 71, as in FIG. 19, is proportioned to fit without turning within the inside of the box-shaped space formed by the opposed yokes Y and Y, but with sufficient clearance to permit plates with buttons 70 of different sizes, for different sized springs, to be placed in position or removed without difficulty.

Side arms 65 of yoke Y are correspondingly tapered at their pole ends and have aligned holes 73 therethrough. Yoke Y is pivotally connected to utility pole P, as by a short length of cable or a link 74 which extends through holes 73 in both yoke arms 65, as in FIG. 16, and through the eye of an eyebolt 16', which is attached to the pole. Either type of attachment allows the breakaway connector to follow the normal swaying movements of the suspended cable C and to remain longitudinally aligned therewith. As in FIGS. 16 and 18, the end of each arm 67 is tapered at each side and includes a central notch 75 and a pair of parallel, longitudinal slots 76 on opposite sides of the notch. Slots 76 of lower arm 65 are in alignment with slots 76 of upper arm 65, while notch 75 of the upper and lower arms are also in alignment.

A releasable connective means connects arms 67 of cable facing yoke Y to cable C. Such a connective means may include a matched pair of flat, L-shaped arms A, a detent bar E pivotally connected therebetween and a ring 78 looped over an upright portion of the detent bar and through an eye 79 at the adjacent end of the cable C. Each L-shaped arm A, as in FIG. 20, includes an upright leg 80, the upper and lower ends 81 and 82 of which extend through the upper and lower arms 67 of yoke Y and which is provided with upper and lower notches 83 and 84 adapted to be received in the respective slots 76, the notches being held in the slots by the force of spring 69, since the front of each leg abuts against base 66 of yoke Y. Each arm A, as in FIG. 20, also includes a rearwardly extending, lower leg 85 which is rounded at the rear end and has a transverse hole 86 therethrough for receiving a bolt 87, as in FIG. 18, which extends through both arms and on which a pivot bushing 88 for detent E is mounted. Bolt 87 may be headed at one end and threaded at the opposite end with a nut 89 and associated lock washer at the opposite end.

The detent bar E is essentially flat and normally upright, having an upper, normally horizontal leg 90 and a lower, normally horizontal leg 91, separated at the front by a notch 92 in which a guide bar 93 for ring 78 is installed. Guide bar 93 is provided with a concave slot 94 on the outside, as in FIGS. 17 and 18, for receiving ring 78. Guide bar 93 may be bent to a U-shape,

slipped into notch 92 until it abuts the inside of the notch and the rearwardly extending ends bent toward each other, as in FIG. 16,'to secure the guide bar to the detent bar. Detent bar E may be mounted on pivot bushing 88 by a press fit, while the front end 95 of upper leg 90 is rounded, as in FIGS. 15 and 17, for a purpose described later.

A rectangular trigger block 96 is attached, as by spot welding, to the rear face of base 66 of yoke Y, as in FIGS. 16 and 17, and the lower edge thereof is normally engaged by a normally horizontal trigger abutment 97 at the front edge of lower leg 91 of detent bar E. The front of the lower leg slopes downwardly and forwardly along a bevel 98, from notch 92 to abutment 97, while the front lower corner 99 is prefereably rounded, as in FIG. 17.

As will be noted, trigger block 96 is carried by yoke Y which is secured to pole P, while detent bar E is pivotally mounted on yoke Y and is normally connected to cable C through ring 78. Since the pull of cable C through ring 78 creates a torque on the detent bar E, tending to rotate it in a counterclockwise direction, as shown in FIG. 15, trigger abutment 97 will normally be held in engagement with the underside of trigger block 96, i.e. as long as the pull on cable C does not cause compression of spring 69 sufficient to move yoke Y a predetermined distance, depending on the compressive strength of the spring. However, an unusually heavy pull by the cable C will compress spring 69 so that yoke Y, along with arms A and detent bar E, will be moved to the dotted position of FIG. 17, so that detent abutment 97 will be moved to the dotted position shown and abutment 97 will clear the underside of block 96, thereby permitting detent bar E to pivot in a counterclockwise direction, as viewed in FIGS. and 17. As detent bar E so pivots, it will be pulled by cable C to the dotted position of FIG. 15, and, as it so pivots, ring 78 will separate from notch 92, riding around the curved end 95 of upper leg 90 of the detent bar E. As detent bar E pivots, lower leg 91 and particularly the front end of abutment 97 and the curved lower front corner 99 of lower leg 91 will move unobstructedly through notch 75 in upper arm 67 of yoke Y, with ring 78 moving to the dotted position of FIG. 15. As the cable C is released, the disconnects D for the electrical wires, such as of the type shown in FIG. 1, will also release, so that the cable and wires may fall harmlessly, at least from an electrical standpoint, to the ground.

To reattach the cable to detent bar E, the cable can be pulled by a suitable device and the detent bar further rotated in a counterclockwise direction until trigger abutment 97 again engages the lower edge of trigger block 96, with the front of lower leg 91 of the detent bar passing through notch 75 of lower arm 67 of yoke Y. Or, the detent bar E may be rotated in a clockwise direction until rounded corner 99 engages block 96, with corner 99 acting as a cam against the block to compress spring 69 until abutment 97 snaps past block 96.

Any size or strength of compression spring, or springs, may be used between the yokes to vary the cable pullrequired to release the cable. A spring strength should normally be used which will release the cable under overload conditions which approach the strength of the cable connections, as at eyebolt 16 or a similar connection at the opposite end of the cable, or the yield point of the cable, if less. A series of interchangeable springs may be provided to give the proper cable release depending on the size, strength, length and other characteristics of the particular support cable or the end connections therefor. To substitute one spring for another, a suitable clamping tool, such as a C-clamp, may be used to exert pressure against the block 69 and the front side of base 68 of yoke Y, in order to compress spring 69 and permit arms A to be moved against the rear edges of slots 76, which have a greater length than the width of upper leg 80 and lower end 82 of the arms. Then, the arms A may be moved upwardly into slots 76 until lower ends 82 of the arms clear the lower arm 67 of yoke Y and arms A then moved forwardly at the lower ends until the front edge of arm 67 is cleared, whereupon the arms A are slid downwardly, while inclined forwardly, for removal. The clamping tool is then released, the yokes Y and Y slid apart and the spring 69 and plates 71 removed, so that a different spring, along with plates 71 having appropriate buttons 70- thereon, replaced within the yokes. 'Ihe yokes are slid back together and the clamping tool is then reapplied, so that the arms A may be replaced, using operations similar to those described above but in reverse order. Of course, the operator makes sure that notches 83 and 84 engage the front edges of slots 76, as the clamping tool is released.

We have now described our invention in considerable detail. However, it is obvious that others skilled in the art can build and devise alternate and equivalent constructions which are nevertheless within the spirit and scope of this invention.

What is claimed is:

1. A safety cable breakaway connector interposed in the span of a suspended cable extending between anchors and comprising:

a. a body means connecting with the anchor at one side of the cable span;

b. a loop means connecting with the remainder of the cable span;

c. a pivot means carried upon the body means;

(1. a rotatable detent means mounted upon the pivot means including a seating arm and a trigger means;

e. a holding means on the body means normally engaging the trigger means with the seating arm rotated to a lateral position with respect to the cable, and with the seating arm being embraced by the loop means and thereby interconnecting the body means with the remainder of the cable; and

f. said body means including shifting means which is shiftable responsive to an excess pull on the cable span to shift said pivot means with respect to the holding means and thereby release said trigger means therefrom, thereby permitting said seating arm to rotate from the lateral holding position towards a longitudinal position, whereby said arm will swing out of the embrace of the loop means to separate the and-remainder of the cable from said anchor.

2. In the connector defined in claim 1, wherein:

said loop means forms a closed loop and both said detent and said trigger swing through said loop upon disengagement with said link.

3. In the connector defined in claim 1, wherein:

said body means includes opposed, interfitting U- shaped yoke members, with resilient means within said yoke members exerting a force against the respective inside ends thereof;

said detent means is pivotal on mounting means extending toward the cable from one of said yoke members;

said holding means is mounted on the outside of the base of the opposite yoke member; and

said detent means is pivotal in one direction for release of said cable and, after release of said cable, pivotal in either direction to its initial position.

4. In the connector defined in claim 3, wherein:

the sides of said one of said yoke members are provided with slots for clearance of the end of said detent member during its pivotal movement.

5. In the connector defined in claim 3, wherein:

said detent means is provided with a trigger abutment engageable with an edge of said holding means for release of said detent means when a pull on the cable produces a predetermined compression of said resilient means;

said detent means is pivotal for release of said cable means and then further pivotal in the same direction for engagement with said holding means; and said detent means is provided with a cam surface for engaging the base of said opposite yoke member to compress said resilient means when pivoted in an opposite direction, after release of said cable,

whereby said trigger abutment may snap past said holding means to said engaged position.

6. In the connector defined in claim 3, wherein:

said holding means comprises a block attached to the outside of said end of said opposite yoke member.

7. In the connector defined in claim 1, wherein:

said body means includes opposed, interfitting U- shaped yoke members, with a coil spring within said yoke members exerting a force against the respective inside base thereof; and

a plate disposed against the inside of the respective base of said yoke members, each said plate having means for centering the corresponding end of said coil spring. I

8. In the connector defined in claim 7, wherein:

said interfitting yoke members provide a rectangular box-like structure;

said plates are correspondingly rectangular; and

said spring engaging means comprise circular buttons mounted on the respective plates.

9. In the connector defined in claim 1, wherein:

said pivot means is mounted upon a rod extended into a tubular portion of said body means; and

i said shifting means includes:

a resilient means holding said rod within said tubular portion whenever the cable is under normal tension, but permitting said rod to extend from the body a predetermined distance responsive to the said excess pull on the cable.

10. In the connector defined in claim 9, wherein said resilient means comprises:

a compression spring, said rod extending therethrough; an adjusting means adapted to tighten the compression spring to any selected degree of compression;

11. In the connector defined in claim 9, wherein:

said trigger means comprises a trigger pin directed towards said body means; and

said holding means comprises:

a sheath means normally receiving said trigger pin to secure the detent means in position, but said trigger pin being pullable from said sheath means whenever the aforesaid rod is extended from said body to the said predetermined distance.

12. In the connector defined in claim 11, wherein: said trigger pin is mounted for adjustment to positions inwardly and outwardly within said sheath.

13. In the connector defined in claim 1, wherein:

said body means includes a tubular member;

a rod extends longitudinally into said tubular member;

said shifting means normally holds said rod within said tubular member, but permits said rod to extend therefrom in proportion to the pull on the cable;

said detent means seating arm is pivotally connected to the outer end of said rod and is normally disposed at right angles thereto to be embraced by said loop means;

said trigger means is a pin outstanding from the opposite end of said seating arm detent in a normal direction opposite said loop means; and

said body means includes a sheath for receiving the end of said trigger pin, whereby said trigger pin is within said sheath, said trigger pin means being released from said sheath whenever the rod is extended from said tubular member responsive to cable pull ofa predetermined extent, to permit the seating arm to swing about its pivotal connection with said rod and disengage said loop means. 14. In the connector means defined in claim 13,

wherein:

said loop means is formed substantially as a rectangular loop with the length of the sides of the loop and the spacing between these sides being such as to permit the seating arm to freely swing within the loop between engaged and disengaging position. 15. In the connector defined in claim 13, wherein: said tubular member is cylindrical and closed at the front end except for space for movement of said 15 rod; and

said sheath is hollow and cylindrical, disposed parallel to said tubular member and connected thereto by a bar attached along one edge of said sheath and along the opposite edge of said tubular member. 16. A safety device for an electrical system including a cable for supporting a series of electrical wires extending from a pole to a building, comprising:

a breakaway connector adjacent said pole and connected between siad pole and said cable, including:

body means connecting with one side of the cable span, link means connecting with the other side of the cable span, and releasable holding means associated with the body means normally engaging the link to hold the span of the cable together, but releasable responsive to a predetermined pull on the cable to permit the link to be disengaged from the holding means and thereby separate the cable,

disconnect means adjacent said pole in each said electrical wire for disconnecting said wires when said connector releases said cable, including:

a male portion and a female portion, each connected to a wire end and constructed and arranged to interfit to provide an electrical connection therebetween, but to be pulled apart on the imposition of a pull on said cable sufficient to produce release of said cable connector and the resulting pull on said disconnect by said wire;

said female portion being provided with a socket;

said male portion being provided with a stub receivable in said socket, said stub being interiorly threaded with tapered threads and provided with longitudinal slots; and

a threaded member engaging the interior threads of said stub for longitudinal adjustment, to adjust the friction fit between said male stub and said female socket.

17. In a safety device as defined in claim 16, wherein:

a sheath having the waterproof properties of plastic surrounds said male and female portions and overhangs the ends thereof, said sheath being attached to said female portion, so as to remain attached to said female portion when said male portion is pulled therefrom.

18. In a safety device as defined in claim 17, wherein:

said female portion, at its outer end, is provided with a hole receiving a wire end, said female portion being formed of material permitting crimping onto said wire end;

said male portion is provided, at its outer end, with a hole for receiving a wire end, said male portion being formed of a material permitting attachment to said wire end by crimping; and

said female portion is provided with an exterior circumferential groove for attachment of said cover.

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Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4184731 *Apr 3, 1978Jan 22, 1980Messerschmitt-Bolkow-Blohm GmbhElectrical connector for use inside a tube such as an ejector tube
US4195192 *Oct 2, 1978Mar 25, 1980Hackney-Glasscock, Inc.Safety disconnect switch for suspended cables
US5315064 *Nov 8, 1991May 24, 1994William D. PiperSuspended line breakaway device
US5623122 *Jul 1, 1994Apr 22, 1997Donald W. AndersonMethod and apparatus for service cable disconnection
US5789700 *Jan 19, 1996Aug 4, 1998Young; J. RonaldGrounding device with mounting brackets
US6303857Oct 19, 1999Oct 16, 2001D.O.T. Connectors, Inc.Mast lighting system
US6872883Aug 26, 2003Mar 29, 2005Thomas A. GinsburgMast lighting system
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US7368660Nov 24, 2006May 6, 2008Claude HardyAnti-cascading suspension clamps for overhead power transmission lines
US7973672Aug 25, 2008Jul 5, 2011The Southern CompanyFallen conductor warning system having a disruption assembly
US8054195May 19, 2011Nov 8, 2011The Southern CompanyFallen conductor warning system
USRE39093 *Feb 12, 2003May 9, 2006Duraline, A Division Of J.B. Nottingham Co., Inc.Mast-type outdoor lighting system
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Classifications
U.S. Classification439/451, 439/296, 248/64, 256/10, 439/271, 174/40.00R, 200/79, 174/40.0TD
International ClassificationH02G7/00, H01R13/58, H02G7/18
Cooperative ClassificationH02G7/18, H01R13/58
European ClassificationH02G7/18, H01R13/58