US2747010A - Transposition bracket - Google Patents

Description

y 2, 1956 w. G. MILNE ET AL 2,747,010

TRANSPOSITION BRACKET Filed Nov. 7. 1952 "l mm 6068/64 6 Prose-Er @C 4 vv-amvex TRANSPOSITIGN BRACKET Winford G. Milne and Frederick G. Ridgers, Hamilton,

Gntario, Canada, assignors to N. Slater Company Liniited, Hamilton, Ontario, Canada Application November 7, 1952, Serial No. 319,216

2 Claims. (Cl. 174-453) This invention relates to a transposition bracket.

As is known, a transposition bracket is used where one conductor of a line has to cross over the other conductor of the line. Each conductor thus subtends two angles at the transposition bracket. Whether the bracket is at a cross arm or at mid-span, the tension in each of the conductors causes a resultant bending moment on the pin supporting the insulator to which the conductor is attached.

Thus, the insulator-supporting pins of one pair of insulators (say on one side of the cross arm) tend to bend one toward the other; likewise, the insulator-supporting pins of the other pair of insulators (on the other side of the cross arm) tend to bend one toward the other.

As a conductor sometimes bodily moves longitudinally, it is desirable that the insulators, if of the pin type, which support the conductors should be free to rotate on their supporting pins; otherwise, one insulator screws itself tightly on its pin, while the other insulator unscrews itself, a condition which may cause failure.

The objects of the invention, therefore, are to improve on known transposition brackets.

A specific object is to provide a transposition bracket in which pairs of insulator supports are connected together, respectively, the insulator-supporting pins of each pair which tend to bend one toward the other being, in effect, rigidly connected one to the other.

Another specific object is to provide a transposition bracket in which the pairs of insulator supports are, in ettect, connected together by composite structures comprising a compression member and a tension member.

Another specific object is to provide a light, simple but sturdy transposition bracket.

Still another specific object is to provide a transposition bracket in which the insulators, in the form of spools, are freely rotatably supported.

in the drawing, wherein like numerals of reference indicate corresponding parts in the various figures- Figure l is a plan view of a transposition bracket made according to this invention;

Figure 2 is a side elevation of Figure l; and,

Figure 3 is an end view of Figure 1, as seen from right to left in Figure 1.

Referring now by numerals to the drawings, the bracket, designated as 10, is shown as secured to a cross arm M as by bolts N.

The bracket assumes generally the form of an H as seen in plan, presenting laterally-spaced parallel arms 11 and 12 adapted to extend on either side of the cross arm. In the form shown, the arms are conveniently connected together as by a transverse member 13, butt-welded to the arms. The member 13, through which the bolts N extend, provides a supporting base.

The ends of both arms are curved upwardly and inwardly to present short U-shaped portions 14 forming supports for the four spool type insulators A, B, C and D.

A portion of the arm 11 is bent as at 15 so as to ofiset the seat for the insulator A upwardly with respect to the 1 nixted States Patent insulator C. In other words, the seat of the insulator A is at a higher level than that of the insulator C. Likewise, the arm 12 is ottset as at 15 so as to position the insulator D higher than the insulator C. Both arms are thus similarly formed so that the mating insulators A and D are at the same level, and the mating insulators B and C are also at the same level.

The mating insulators A and B are rotatably mounted to their respective arms 11 and 12 by a skewed or distorted U-shaped member 18. The parallel legs 19 of the member 18 pass through holes in the arms and serve as journals around which the insulators freely rotate.

The insulators are held in operative position to the member 18, more particularly to the legs 19, as by washers 20 and cotter pins 21.

Resting on the portions or seats 14 of the arms, and connecting the legs 19 of the U-shaped member 18, is a rod 24. Conveniently, the rod is connected to the two legs by flattening its ends and providing holes through which the legs 19 pass. The connection or rod 24 thus forms a strut or compression member, since the insulators A and B tend to be displaced bodily one toward the other. The strut, acting in compression, thus substantially prevents the bodily displacement of one insulator toward the other.

As the thrust or force tending bodily to displace the insulators A and B toward one another is imposed upon the insulators above the axis of the strut, the ends 14 of the arms are subjected to a torsional efiort, tending to twist or distort the same. However, the horizontal or connecting leg portion of the member 18 now comes into play, acting in tension to prevent distortion of the ends of the arms.

Washers 17 preferably are provided under the insulators to facilitate their turning.

The other two insulators C and D are likewise journaled on a skewed U-shaped member 18A mounted to the arms 11 and 12 in the manner of the member 18; and struts 24A are provided and mounted in operative position in the manner of the struts 24.

We claim:

1. In a transposition bracket, the combination of a supporting base adapted to be secured to a cross arm and including a pair of arms having bent-back portions extending above the plane of said base and each providing supports for a pair of insulators diagonally opposite ends of each arm being bent upwardly whereby each pair of diagonally opposite insulators are at difierent respective levels, said portions having vertically-directed apertures, generally U-shaped bars each having vertical parallel legs and horizontal bight portions the parallel legs of which are adapted to be inserted vertically through said apertures to extend above said bent-back portions to receive the insulators, the angle between the vertical legs and the horizontal bight portions being greater adjacent the higher insulators and less adjacent the lower insulators, and a strut having apertured end portions adapted removably to be attached to said parallel legs above said bent-back portions, said strut and the transverse leg of said U-shaped member providing compression and tension members, respectively, of a structure tending to resist displacement of said parallel legs one toward the other.

2. In combination, a member includin a pair of paral lel arms having apertured U-shaped end portions forming supports, one end of each of said arms being bent upwardly, each pair of diagonally remote ends of said arms being in the same plane and at a different level than the other diagonally remote pair of arms, a U-shaped member the parallel legs of which extend upwardly through said end portions to project above the planes of said supports, a strut having apertured ends through which said parallel legs extend, said ends being supported by said U-shaped end portions, spool insulators rotatable on said parallel legs above said supports each pair of diagonally remote insulators being at a different level, and means including pins through the upper portions of said parallel legs removably locking said insulators to said parallel legs and suspending said U-shaped member from said insulators, said struts and said U-shaped members References Cited in the file of this patent UNITED STATES PATENTS Case Mar. 2, 1948 Wheeler et al. Oct. 24, 1950

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