US2695391A

US2695391A - Electric conductor saddle

Info

Publication number: US2695391A
Application number: US316734A
Authority: US
Inventors: Ralph R Pittman; Paul G Whitmore
Original assignee: PITTMAN
Current assignee: PITTMAN
Priority date: 1952-10-24
Filing date: 1952-10-24
Publication date: 1954-11-23
Anticipated expiration: 1971-11-23

Description

Nov. 23, 1954 R. R. PlTTMAN Em 2,695,391

ELECTRIC CONDUCTOR SADDLE Filed Oct. 24, 1952 INVENTORS. '1

'duc'tor and a tap clamp,- da'mage to the line conductor either by (1) arcingat- "tendingthe connection or disconnection of the tap conductor; (2) excessive clampingpressure; or'(3) vibration United States Patent 0 ELECTRIC CONDUCTOR SADDLE Ralph R. Pittman, North Little Rock, Ark.,.andPaul G. Whitmore, New York, N. Y.; said Whitmore assignor to. said Pittman Application-October 24, 1952, Serial No. 316,734

4'Claims. (or. 339-409 v This invention relates to electric conductor saddles adapted to be interposedbetween .an electric line .con-

for the purpose of preventing at a point of concentrated mechanical'loading.

Because of desirable electrical conductivitydnherent in substantially pure copper and aluminum wires, electric conductors of one or the other of thesemetals are -more commonly used in electric distribution systems than any other materials. Both copper and aluminum, andparticularly the latter, are soft metals and susceptible to cold flow and consequent distortion and weakening when subjected to the concentrated contact pressure resulting from the direct application to the conductors of ordinary screw-type connectors. In addition, it is i-well known that the concentrated'weight of such con nectors, along with the Weight of an attached tap wire,

'nection or disconnection of a tap-wire connector directly engaging the line wire provides a weak spot which'hastens its failure.

That the above-mentioned unsatisfactory conditions "brought about by tap-wire clamps applied directly to the conductor have been long recognized is evidenced by the several arrangements currently in wide use for'mitigating the expected damage. One plan proposes the use of a lighter-weight clamp; another slightly wider jaws on the clamp for engaging the conductor. Probably the most successful is the application of two clamps spaced apart along the conductor, and joined by ahorizontal wire on *2.

which the tap-clamp is mounted. -In each situation, the effectiveness varies directly with the cost, the last mentioned being relatively costly under the most favorable conditions, and particularlycostly when applied to conductors oflarge-diameter because 'ofthe higher cost of 'the larger clamps.

It is an object of the present invention to provide a saddle of inexpensive construction which can be easily and quickly applied to live conductors, of relatively large difference in diameter, and which, after application, will provide a plurality of spaced apart, spring-pressed conductor-engaging portions, and, at a point remote from the conductor, a curved, resilient, tap-wire clamp-engaging portion.

The invention is advantageous because excessive con centrated pressure on the conductor is rendered impossible. The length of the line conductor engaged by the saddle is optional within wide limits with little difference in cost. The cost is principally determined by the length of wire selected to form the saddle, and the resilient engagement of the saddle at spaced-apart portions of the conductor acts to reduce vibration and eliminates any tendency to form a node at any point along the wire. Any burning from arcs or cutting of the line conductor is impossible; such effects can occur only on a portion of the saddle where they are of no importance.

In the drawing:

Fig. 1 is an elevation of a preferred embodiment of our improved conductor saddle.

( .1) Fig. 2 is a perspective v ew of our improved conductor 2,695,391 Patented Nov. .23, 1954 upwardly in spaced relationship to merge respectively with the rearwardly and'slightly downwardly conductorengaging ears '17 and 18. From the respective rearward ends of the

ears

17 and 18 are extendedthe diverging outwardly and upwardly extending

portions

19 and 20, which respectively merge into the upper ends of the laterally spaced coiled portions21 and 22, and the respective lower ends of the latter-portions merge with the inwardly and coaxially extending

portions

23 and 24, the inward ends of the latter being terminated and a point indicated by the numeral'26, andrigidly fastened together in end to end relationship bymeans of'the compression sleeve 25. The completed'structure forms three coiled portions arranged in triangular relationship, and generally facing in the same direction, with the axes of the respec tive coiled portions extending transversely with respect to the'plane of the triangle.

To assure ready accessibility of the eye 14 for convenience in operating the saddle and the attachments to be made thereto, the'upwardly extending

portions

15 and 16 are sufiicientlyflong to position the eye 14 below the substantially horizontally extending portions 23 and '24, and the fastening sleeve 25.

Fig. 2 illustrates'the appearance of thesaddle when relaxed and in the course of being applied to a lineconductor 11. The numeral 27 designates a commonly used type of insulated tool or clamp :stick, the end of which is provided with clamping means (not shown) for grasping the saddle at the eye portion 14. In applying the saddle to anenergized conducton'the upper portion of the eye'14 is placed 'fla'twise against one side of the conductoiyinwhich position the lower portions of the coiled

portions

21 and 22 are" above the conductor. The lower portions of the convolutions of the coiled

portions

21 and 22 are norm-ally spaced apart for the reception of a line conductor, and as the saddle is moved downwardly While the'portions '15 and 16 are slidabl-y engaged with the conductor, the

coiled portions

21 and 22 straddle the conductor. As "thedownwardmovement is continued,

the upper portions of the coiled

portions

21 and 22"first come to rest: across the'uppersurface of the conductor, following which condition the'ears 17 and 18 snap under the conductor between the coiled

portions

21 and 22 under the stress exerted'thereon by the deformation of the resilient coiled portions. 'The saddle'is thereby resiliently latched on the conductor in spring pressed contact therewith at eight spaced points, of which six are with the

coiled portions

21 and 22, and two with the

ears

17 and 18. The saddle is preferably formed so that the distance between the coiled-portion contacts is large in comparison with the diameter of the associated conductor.

The tool 27 may then be detached from the eye 14, and any desired type of tap clamp, such as that designated at 12, along with its associated tap wire 13, may be applied to the eye portion 14. It may be noted that any clamptype screw connector applied to the eye portion 14 will necessarily clamp a curved portion of the eye portion, and since such a curved portion is of resilient material, its deformation under pressure results in a spring-pressed connection between the saddle 10 and the tap-wire connector 12. The saddle 10 as it appears when resiliently mounted on the conductor 11 is shown by Fig. 1, and it may be noted that the

ears

17 and 18 are moved both downwardly and inwardly with respect to their relaxed positions as shown in Fig. 2.

The saddle 10 may be readily formed to fit a wide range of conductor diameters, and it will be readily seen that it may be designed in various sizes to meet specified conditions. One practical design which has been found both effective and inexpensive is formed from #8 AmericanWire Gauge copperweld wire, the coiled

portions

21 and 22 having a diameter of about 3 inches and being laterally spaced on centers about inches apart. The eye 14 has a diameter of l /z-inches, and is positioned 3 /2-inches below the centers of the

coiled portions

21 and 22, and l /z-inches below the compression sleeve 25. The lower portion of the rearward turn of each coiled

portion

21 and 22 is spaced about 1 inch from the respective lower portion of the forward turn for convenience in straddling the saddle on a conductor. The

ears

17 and 18 extend rearwardly 1 inch, and in the relaxed position, the tops of the ears are at an elevation of %-inch above the tops of the

coiled portions

21 and 22.

We have found that our saddle when constructed as above described will satisfactorily fit all sizes of conductors not smaller than /sinch in diameter, and no larger than -"z 4-inch in diameter, which range encompasses practically all conductors in common use as overhead conductors in present-day electric distribution systems. The weight of this particular saddle is only 7 ounces, which is spread along a 5 inch length of conductor.

It will be apparent that the saddle may swing around the conductor as may be required to adapt to the direction of take-0d of the tap wire, and. that any lateral movement of the line conductor, such as may be caused by wind conditions will tend to keep the contact surfaces clean and bright. It may be also noted that the mere application of the saddle removes surface deposits from the conductor at the points of contact. If desired, the upper portion of the saddle may be coated with a metal compatible with conductors formed of any one of several metals; e. g. it may be cadmium-plated and thereby made suitable for use on either copper or aluminum conductors.

From the above description, it will be clear that an effective, inexpensive and easily operable conductor saddle is provided by our invention, having the several advantageous characteristics above set forth.

What is claimed is:

1. An electric conductor saddle of resilient metal wire comprising generally at least three spaced coiled portions facing the same direction and in triangular arrangement, two of said coiled portions having spaced-apart turns to permit hanging the saddle from a line wire extending within and laterally across said two coiled portions, the respective end portions of each of said two coiled portions being positioned respectively above and below said line wire, a substantially horizontally extending portion icining the respective lower ends of said two coiled portions,

a third coiled portion positioned below said horizontally extending portion, the respective ends of said third coiled portion extending upward in spaced relationship between said two coiled portions, and latching portions in the form of ears adapted to resiliently engage the lower surface of the line wire and extending rearwardly from the upper ends of the portions joining said third coiled portion, the respective rearward ends of said ears extending upwardly and laterally over said line wire and merging with the respective upper ends of said two coiled portions.

2. An electric conductor saddle fashioned from a length of resilient metal wire, comprising a pair of spaced coiled portions formed with the respective convolutions thereof lying in intersecting planes, the convolutions of the respective coiled portions being spaced apart at the respective lower ends thereof and adapted to straddle a line wire received between and extending across said convolutions, inwardly and substantially horizontally extending portions from the respective lower ends of said coiled portions arranged to join said lower ends of said coiled portions to restrain outward movement thereof, an eye positioned below said horizontally extending portions, a pair of legs extending in spaced relationship upwardly from said eye, rearwardly extended latching ears at the respective upper ends of said legs, and outwardly and upwardly extending portions joining the respective upper ends of said coiled portions with the respective adjacent rearwardly extended ends of latching ears.

3. An electric conductor saddle adapted to be resiliently mounted on a line wire, comprising a single piece of resilient metal wire having the respective ends thereof joined in opposed coaxial relationship, a pair of laterally spaced coiled portions formed with the respective turns thereof lying in intersecting planes and merging with said ends, said coiled portions facing the same direction and being adapted for the reception of the line wire across each coil and between the respective turns thereof, latch ing portions joined to said coiled portions to which said coiled portions tend to impart latching movement, said latching portions being in the form of ears extending rearwardly between said coiled portions, the respective rearward ends of said ears being joined to the respective upper ends of said coiled portions above the line wire and the respective forward ends of said ears being extended downwardly in spaced relationship below said coiled portions, and a tool-receiving coiled portion formed at the lower end of the last-mentioned downwardly extended portions.

4. An electric conductor saddle formed from a single length of resilient material shaped to provide an eye, a pair of legs extending upwardly from said eye, a pair of conductor-engaging ears extending rearwardly from the respective upper ends of said legs, a pair of coil-merging portions diverging laterally and upwardly from the rearward ends of said conductor-engaging ears, a pair of laterally spaced coiled portions joining at their respective upper ends thereof the respective coil-merging portions, the convolutions of said coiled portions being spaced apart at the lower ends thereof and adapted to straddle a conductor received between and extending across said convolutions, the respective lower ends of said coiled portions being joined above said eye and below said conductor-receiving ears.

References Cited the file of this patent UNITED STATES PATENTS Number Name Date 2,096,790 Crump Oct. 26, 1937 2,229,403 Benander Jan. 21, 1941 2,297,036 Tallman Sept. 29, 1942