US3026368A - Conductor clamp assembly for use on pole top insulators - Google Patents

Description

March 20, 1962 E LINDSEY 3,026,368

CONDUCTOR CLAMP ASSEMBLY FOR USE ON POLE TOP INSULATORS Filed March 10, 1959 INVENTOR'.

L.E. LINDSEY United StatesPatentO 3,026,368 I CONDUCTOR CLAMP ASSEMBLY FOR USE ON POLE TOP INSULATORS L. E. Lindsey, 222 Vista Ave., Pasadena, Calif. Filed Mar. 10, 1959, Ser. No. 798,483 20 Claims. (Cl. 174-169) This invention relates to conductor clamps and more particularly to an improved and simplified conductor clamp assembly specially designed for use in detachably connecting a power conductor to a pole top type insulator and in such manner that the conductor can be serviced and replaced if necessary without interruptionof electrical service. There is a continuing need for power transmission lines of the type utilizing pole top type insulators for power conductors and utilizing conductor clamping means so provide an economical and effective method of anchor ing the conductors to the insulators'but unfortunately, these are not adapted for servicing while the conductor is hot; nor can the conductor clamping device be loosened and retightened easily and with the safety'desirable in the expeditious and low-cost servicing of power lines.

This problem has been recognized and there has been provided by prior designers various clamp assemblies useful in lieu of tie wires for anchoring the conductors to the tops of pole top insulators. However, these prior constructions are subject to numerous defects and shortcomings sought to be obviated by the present invention. Among these disadvantages is the fact that prior structures are excessively complex in design, costly to construct, and both difficult and costly to service in the field, as well as dangerous to service personnel. In particular, prior designs have been unsuitable for servicing while the conductor supported thereby is maintained in service.

By the present invention there is provided a simplified conductor clamping assembly characterized by the ease and speed with which it is securable to the insulator and particularly in that it is adapted to be serviced conveniently with simple and effective wrenches and gin poles Without discontinuing electrical service or hazard to service personnel. The conductor clamp utilizes a single movable jaw having a single threaded adjuster arranged to be tightened and loosened by simple wrenches. The movable clamp member is shiftable through a wide range between open and closed positions and includes interlocking stops and detents so arranged that it is impossible to remove the clamping jaw except by compound movement thereof upwardly away from the clamp body after the conductor has been removed, Another feature of the conductor clamping jaw is its suitability for clamping a wide range of conductors by the simple expedient of reversing the assembly position of the clamping jaw relative to the stationary side of the conductor clamp.

Another feature of the invention is the provision of a single through bolt in cooperation with a pair of insulator clamping jaws and operable when tightened to lock the latter jaws in rigid clamping relation to the top of the insulator. The insulator clamping jaws are so designed relative to the mounting through bolt that tightening of the bolt hows the latter in a direction to remove looseness between the threads thereof and the conductor supporting member carried in the midportion of this bolt.

5,025,353 Patented Mar. 20, 1952 The elimination of free play between the threads of the conductor support and the assembly mounting bolt avoids possibility for arcing and the resulting source of interference to radio and television receivers in the surrounding area. Additionally and importantly, the clamping jaws and through bolt are so designed that, on tightening, threads of the bolt are forced to bite into a wall of the insulator clamping jaws in such manner that the clamping nuts act' as lock nuts. Accordingly single nuts at the opposite ends of the through bolt sulfice without sacrifice in safety.

Accordingly, it is a primary object of the present invention to provide an improved conductor clamp for use on a pole top type insulator.

Another object of the invention is the provision of a conductor clamp for use with a pole top type insulator featuring means for servicing the line and the clamp without interrupting power service.

Another object of the invention is the provision of a simplified and improved conductor clamp for detachably securing a power conductor to the top of insulators originally designed for use with tie wires. Another object of the invention is the provision of a unitary clamping assembly having a minimum number of parts and including means for clamping the assembly detachably to a pole top type insulator as well as a second clamp designed for operation from ground level to releasably clamp a high tension conductor seatable therewithin.

Another object of the invention is the provision of a power conductor clamping assembly featuring a single threaded member controlling tightening and clamping of the conductor and cooperating with a single movable clamping member which is reversible to accommodate both large and small diameter conductors.

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 fragmentary view in side elevation of a pole top type insulator showing the conductor clamp of the present invention secured thereto;

FIGURE 2 is an enlarged fragmentary view with parts broken away and taken generally along the line indicated at 2-2 on FIGURE 1;

FIGURE 3 is a view of the conductor clamp taken along the broken line 33 on FIGURE 2, the conductor being removed; and

FIGURE 4 is a fragmentary view looking downwardly into the conductor supporting saddle as viewed in part along line 4-4 on FIGURE 3.

Referring to the drawings and more particularly to FIGURES l to 3, there is shown a conductor clamping assembly designated generally 10 embodying the features of the present invention. Assembly 10 is shown clamped to the usual tie wire seating groove 11 encircling the top of a pole top type insulator 12 mounted on a supporting pin 13 forming part of a pole structure not otherwise shown but understood to be of conventional construction.

The conductor supporting and clamping assembly 10 includes a main support comprising a headless through bolt 14 threaded throughout its length and adapted to be supported parallel to and spaced somewhat above the usual transverse conductor seating groove 15 across the top end of insulator 12. To this end there is provided a pair of identical rigid insulator clamping members 17, 17 of limited resiliency each having a pair of arcuate fingers 18, 18 cooperating to embrace and seat within tie wire groove 11 of the insulator. The upper or main body portion 20 of these clamps is provided with a bore on the opposite ends of through bolt 14.

21 through which through bolt 14 extends. A hood 22 projects toward the'verticalcenterline of the insulator and closely overlies the upper side of through bolt 14 and tends to limit pivoting of jaws 18 away from one another as these jaws are forced into the groove by the tightening of independently operablenuts 24-supported In counteracting this tendency of the clamps to rotate away from one another skirts or hoods 22 tend to force the centralpor tion of the through bolt toward the top of the insulator bowing it downwardly through an appreciable distance, this bowing having a purpose which will be described more fully presently.

"Another feature of the insulator clamping jaws 17 is the provision of inwardly extending tangs or bosses 26 which are positioned and shaped to seat in the opposite ends'of the transverse groove 15 across the'to-p of the insulator. Accordingly, it will be apparent that tangs 26 cooperate with jaws 18 in the proper positioning of clamp- 1 ing assembly on the insulator and particularly in holding the same against rotation or the sidewise shifting of the assembly relative to the top of the insulator.

The means for supporting and clamping electrical power conductor 30'comprises an elongated main body or saddle member 31 preferably having the configuration illustrated and including an elongated open top slot or v conductor seating groove 32 extending lengthwise of its main body. A supporting bracket or boss 33 integral with the underside of this body has a transverse threaded bore 34 mating snugly with the'threads of throughfbolt 14. e The longitudinal axis of main body 31 and conductor seating groove 32 lie at right angles to the axis. of

threaded bore 34 with the result that,-in its assembled position, saddle 31 extends crosswise of through bolt 14 and can be pivoted through a small arc about the axis thereof. Owing to the snug mating fit between the threads of bore 34 and the threads of through bolt 14 augmented by the downward bowing of this bolt upon the tightening of nuts 34, a tight frictional fit is provided between saddle member 31 and the threads of the through bolt. Accordingly, there is no opportunity for arcing of leakage currents between these threads with the result that the described assembly is notable for its freedom from tendencies to produce interference on radio and television receivers in the area of the transmission line.

Additionally and of particular importance is the fact the lower inner "side wall 19 of receiving bore 21 for through bolt 14in clamping members 17 is forced to bite into the threads of the through bolt. This action causing the threads to bite into Wall 19 is readily apparent in FIGURE 2, it'being noted that the tensioning of the through bolt causes clamping members 17, 17 to pivot toward one another about fulcrums provided at the points of contact of tangs 26 with the adjacent portions of insulator 12.- For clarity the left hand clamping member 17 has been shown in FIGURE 2 in the position occupied when the through bolt has been fully tightened, whereas the showing of the right hand clamping member 17' is that occupied before the first tightening of this clamping member against the insulator. From the foregoing it will be understood that nuts 24 function in cooperation with the screw thread engagement of clamp wall 19 with the through bolt to obviate the need for an additional pair of lock nuts bearing against the remote end faces of nuts 24, 24; In other words, the described threaded engagement between wall 19 and bolt 14, taken with the action of nuts 24, provides a complete and highly satisfactory lock nut action.

The conductor clamping member comprises. a generally T-shaped clamping element 38 having an elongated head 39 and a downwardly extending boss or stem 40 provided with a threaded bore 41 for the reception of clamping bolt 42. Head 39 of clamping member 38 is slidable along a short guide channel 44 extending transversely of conductor "saddle 31 and opening through one side wall 4 of the saddle in the manner made clear by FIGURES 3 and 4. It will be noted from FIGURE 3 that stem 40 of the clamping member extends downwardly into a dovetail groove 45 to the end that retainer ears 46 integral with stem 40 will have interlocking engagement with the enlargement 48 at the inner. end of the dove-tail slot '45,

for reasons readily apparent from FIGURE 4. g

The conductor engaging portion of clamping member 38 includes a large hook 49 for use in clamping large,

diameter conductors such as'that shown at 30 in FIG- URE 2. When using clamping member 38 to grip smaller size conductors, clamping member 38 is removed, fromits assembled position and turned degrees be-' fore reassembly through entrance 48 in order that the smaller clamping lug 50 will overlie groove 32 of the saddle.

In use, the described clamping assembly is first secured to the top of an insulator 12 by loosening clampingnuts 24 to permit clamping jaws 18, 18 to be inserted into insulator groove 11, care being taken that tangs 26 are seated in the opposite ends of insulator groove 15. Nuts 24 are then tightened causing the midportion of the clamping bolt 14 to be bowed downwardly in the manner described above. The conductor supporting saddle 31 is pivotable about bolt 14 with difiiculty owing to the gripping action of the bowed midportion of bol-t 14. Clamping jaw 38 is then opened widely by loosening the clamping bolt 42 thereby allowing the clamping member to be shifted to the outer end of guideway 44. In this position clamping jaw 49 is disposed entirely outside conductor receiving groove 32. Gin poles'or other conductor handling devices are then employed to handle the conductor as required to seat it within groove 32. Thereafter, long handled wrench devices well known in the art are engaged over the head of bolt 42 and the latter is rotated in a direction to draw clamping member 38 tightly against the conductor to anchor it rigidly in place in saddle 31.

Servicing of the conductor while hot is accomplished by loosening nut 42, the bolt being loosened until the clamping member is shifted outwardly along guideway 44. Gin poles are then used to remove the conductor from the saddle permitting any necessary repair or inspection work to be done upon the clamping member, the pole or upon the insulator and attached conductor clamp. Even should clamping bolt 42 become accidental- 1y detached from the clamping member, it is impossible for the clamping member to become displaced from its assembled position since it is necessary for the member to be removed to its innermost position along channel 44 and thereafter elevated vertically. This operation can be performed only after the conductor has been removed from saddle groove 32. So long as the clamping member is supported along the guideway its threaded bore 41 is in alignment with the bolt hole 51 for fastener bolt 42 and no difiiculty is experienced in re-threading the bolt into threaded bore 41.

Should it be desired to replace a large diameter cable conductor with a smaller one, this can be done by unscrewing fastener bolt 42, moving the clamp to its innermost position and then removing it upwardly from the saddle member. The clamp is rotated 180 degrees to bring the smaller clamping lug 50 into a position overlying conductor groove 32.. While in this position, the

clamp is lowered downwardly through entrance 48 to key hole slot 45, following which bolt 42 is reassembled. While the particular pole top insulator clamping assembly 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 7 details of construction or design herein shown other than as defined in the appended claims.

I claim:

l. A high tension conductor clamping assembly for attachment to the upper end of upright power trans mission line insulators of the type having a transverse groove and an underlying annular groove for seating a conductor tie wire, said assembly including an elongated main support adapted to overlie the transverse groove of an insulator in closely spaced relation to the surfaces of said groove, means including a pair of clamping jaws each adjustably supported on the opposite ends of said main support and shaped to engage within the annular groove of an insulator in a manner anchoring said assembly rigidly thereto as said jaws are forcibly urged toward one another, means operatively carried by said main support for supporting and releasably clamping a high tension electrical conductor extending transversely of and overlying said main body, said last named means being adjustable lengthwise of said main support to permit centering of the conductor directly above the vertical axis of said assembly and of the upright insulator to which the same is clamped in use.

2. A clamping assembly as defined in claim 1 characterized in that said main support comprises an elongated rod threaded substantially throughout the length thereof and having snug threaded engagement with a threaded opening extending transversely through said conductor supporting means.

3. A clamping assembly as defined in claim 1 characterized in that said clamping jaws include bosses projecting toward one another and shaped to extend into the opposite ends of the transverse groove of an insulator and cooperable therewith to prevent relative rotation of said assembly and of an insulator to which the same is clamped.

4. A clamping assembly as defined in claim 1 characterized in that said clamping jaws each include a pair of arcuately arranged fingers positioned to seat in the tie wire groove of an insulator, and additional rigid means projecting from said jaws for seating in one end of the transverse groove of an insulator to prevent rotation of the assembly in either direction about the vertical axis of the insulator.

5. A clamping assembly as defined in claim 1 characterized in the provision of independently operable means at the opposite ends of said main support to permit the tightening of said clamping jaws toward said conductor supporting means by substantially equal increments thereby avoiding the possibility of shifting said conductor supporting means laterally away from its desired position on the vertical axis of the insulator.

6. A clamping assembly as defined in claim 1 characterized in that said conductor supporting means comprises an elongated saddle member having a threaded transverse bore having a snug fit about the threaded midportion of said main support, said saddle member being pivotable through a limited are about the axis of said main support when sufficient force is applied to overcome the friction between said snugly fitting threads.

7. A clamping assembly as defined in claim 6 characterized in the provision of conductor clamping means mounted on said saddle member.

8. A clamping assembly as defined in claim 7 characterized in the provision of a single threaded fastener cooperable with said saddle member and with said conductor clamping means to lock a conductor releasably assembled within said saddle member, said threaded fastener having a non-circular wrench-engaging portion projecting laterally from one lateral side of said saddle member whereby a wrenching tool may be applied'thereto and manipulated from a remote location to loosen and to tighten said fastener.

9. A conductor clamping assembly adapted to be rigidly clamped across the top of a high tension line electrical insulator, said assembly including an elongated threaded main body, a conductor saddle member having a downwardly projecting threaded boss snugly engaging the threaded midportion of said main body and having limited pivotal movement about the axis of said main body, adjustable clamp jaws mounted on the opposite ends of said main body each independently adjustable toward one another along said threaded main body to secure said assembly rigidly to the upper end of an electrical insulator, said saddle member including conductor clamping means adjustable from a remote point in a manner to releasably grip a conductor seated in said memher, the adjustment of said clamping jaws against the top of an insulator acting to bow said main body in a direction to bind the threaded engagement of said threaded boss with said main body thereby minimizing the likeli hood of leakage currents arcing between said saddle member and said main body thereby eliminating radio and the like interference caused by arcing of leakage currents.

10. A clamping assembly as defined in claim 9 characterized in that said conductor clamping means includes cooperating detent means effective to prevent detachment of said clamping means from said saddle member except by compound relative movement of said clamping means and of said saddle member through a predetermined path.

11. A clamping assembly as defined in claim 9 characterized in that said conductor clamping means is reversible and shaped to clamp different size conductors depending in which of two interchangeable positions said clamping means is positioned.

12. A conductor clamping assembly adapted for mounting on the top of a high tension line electrical insulator, said assembly including a conductor-supporting saddle member having adjustable means thereon for releasably gripping a conductor seated in said saddle member,-means pivotably mounting said saddle member on a main support member and including relatively movable surfaces held assembled in snug fitting wiping contact with one another, and adjustable clamping means carried by said support member for rigidly anchoring said clamping assembly to the top of high tension line insulators of a wide range of diameters, said conductor gripping means including a jaw slidably supported for movement toward and away from one lateral side of said saddle member, mterengaging means between said gripping means and said saddle member for preventing accidental disas sembly of said gripping means unless the latter is moved through a predetermined path while the conductor is absent from said saddle member.

13. A clamping assembly as defined in claim 12 characterized in the provision of a single threaded member cooperable with said saddle member and with said condu-ctor gripping means and operable to release or tighten said gripping means relative to a conductor seated in said saddle member.

14. A conductor clamping assembly adapted to be detachably mounted at the top of a pole line insulator of the type having a transverse conductor seating groove across the top thereof and an underlying annular tie wire seating groove, said assembly including a pair of clamping members having arcuate fingers positioned to seat in said annular groove at the opposite ends of said transverse groove, a common threaded member extending through aligned openings at the upper ends of said clamping members, and threaded means mating with the threads esame 7 of said threaded member operable when. rotated in one direction to fo'rce said clamping members toward one another from the opposite sides of an insulator as said in locking said clamping members against. retrograde movement away frorn'said'insulator and is effective to cause the said clamping members to bite into 'andmate with juxtaposed portions of the threads on said threaded member.

15. A conductor clamping assembly as defined in claim 14 characterized in that said common threaded member has a single nut on each end thereof, said nuts being cooperable with the portions of said clamping members having threaded engagement with said threaded member to provide a lock nut action therewith eifective in pre: venting the loosening of said nuts from their tightened positions. V

16. An insulator clamping assembly adapted to be detachably secured to one end of an insulator for a high tension power line wherein the components are subjected.

to severe vibration as an incident to the flow of electrical current therealong, said assembly comprising an elongated main body threaded at its opposite endsand adapted to be supported crosswise of one end of a high tension insulator having an annular clamp-seating groove adjacent one end thereof, a pair of clamping members each having a bore fitting loosely over a threaded end of said main body and each including rigid means shaped to seat firmly in said annular groove, a pair of threaded nut means mating with the threaded'ends of said main body effective as the sameare tightened against the adjacent one of said clamping members to force the latter into tight clamping engagement with said insulator while causing said clamping members to pivot inwardly toward the end of said insulator, said pivoting movement causing portions of the bore walls of said clamping members to be deformed into mating engagement with the threads ofsaid main body in a manner effective to hold said clamps tightly assembled to said insulator despite loosening of said nuts by the severe vibrations to which said assembly issubjected in use.

17. In combination with one end of a high tension power conductor insulator, that improvement which comprises a conductor mounting assembly for use in supporting high tension power conductors from high tension insulators and adapted to accommodate limited sway and .movement'of such conductors without generating radio interference by reason of relative movement between the parts of said mounting assembly, said assembly including means for securing the assembly to one -end of a high tension electrical insulator, conductor clamping means,-

and means movably interconnecting said securing means and said conductor clamping means through a. snug frictional'fit effective to prevent the flow of small arcing currents therebetween which currents cause radio interference.

, 118. The combination defined in claim 17 wherein said snug frictional fit between said securing means and said conductor clamping means comprises mating threads: the juxtaposed facesof which are insnug Wiping surface engagement with one another.

clamping a conductor thereto, means for pivotally connecting said saddle to 'a high tension insulator and including a pair of clamping members engageable with diametrically opposed rim areas of the end of the insulator, a long threaded member extending through said clamping members across the end of the insulator including nut members threadable over the unobstructed opposite ends of said threaded member, the midportion of said threaded member passing through a threaded bore passing trans: versely through said conductor saddle, and the tightening of said nut members to clamp said clamping assembly to an insulator beingelfective to increase the frictional contact between said threaded member and said conductor saddle to avoid possibility of arcing currents between said saddle and threaded member during use of said clamping assembly in a high tension power line, the tightening of said'nut members along said threaded member to clamp the latter to an insulator end being effective to bow the midportion of said threaded member away from a normal straight condition thereof, said bowing being effective to increase the pressure between mating thread surfaces of said elongated threaded member and the threaded bore through said saddle to provide a positive metal-tometal electrically conductive path for leakage currents.

References Cited in the file of this patent UNITED STATES PATENTS

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