US2610818A

US2610818A - Crossarm clevis

Info

Publication number: US2610818A
Application number: US167279A
Authority: US
Inventors: Ridgers Frederick George
Original assignee: SLATER N CO Ltd
Current assignee: N SLATER COMPANY Ltd; SLATER N CO Ltd
Priority date: 1950-06-10
Filing date: 1950-06-10
Publication date: 1952-09-16
Anticipated expiration: 1969-09-16

Description

Patented Sept. 16, 1952 UNITED STATES PA'I`11`TEY FFICE Ai' 'g yiff-.12,610,818 A Y QROSSARM @LEVIS Frederick vGeorge-Ridgers, Hamilton, Ontario,

Canada,assignor`to N. Slater Company, Limitem-Hamilton, Ontario, Canada y Y Appliqationquneio, i950, serial No. 167,2,79

This invention relates to a crossann insulator mounting.v j' L A mountingaccording to the invention is intended primarily to be applied to aA ross arm at which the conductor is to undergo or subtenda change or deflection in its direction. Usually, the conventional pin (metal or wooden) mounting an insulator is adequate where the conductor is straight; but where the conductor has to undergo a change in itsV direction, at a particular insulator, the conventional pin may be inadequate to resist the considerable side thrust or horizontal force Vimposedupon such pin. A special mounting is then necessary. The objects of the invention, generally', are to improve on known Vcross arm insulatormount- 1ngs. Y

A specific object of the invention isvto provide a strong mounting designed to provide maxirnum' strength for a minimunr'weight of nia-k terial used, thus relucingthe weight Vand* cost of the mountingg Another specific objectis to provide amountingdesigned to lresist deformation.

4other'specific object isto vprovide a mounting` which can be manufactured' easily and y' l Another speciiic objeet is to design a mounting whichwill resist'displacementupon the cross arm when attached in operative position. Another speelde object is to so design the mounting thawing nu'lawr is easily applied and aseasily removed.

Still another specific object is to provide a mounting ,which is` held securely to thecross arm by a Single boli@ .and ,once applied, AiS-hld .in .Operative .position against lateral Vdisplacemer it lor rotary. displacementrelatively" tofth'e cross arm. In the drawing, wherein like numerals of reference indicate corresponding parts in the various figures.

AFig-ure 1 is a side elevation of a typical yinsulator in operative position on a mounting made according t9 this .rvgliii y Figure 2 is an end view of Figure l, as from fight t left? ,l '-Figureis a section on line ^3-.13 in Figure; and f I .Figure 4 shows a modified ,for of attaching bolt.

Referring now by numerals to the drawing, I0 shows a typical insulator. II is a metal strap or bar formed substantially to the shape of a U, presenting two substantially parallel legs, that is, an upper leg I2 and a lower leg I3 extending A 2 Claims. (Cl. 24S-220.5).

. 2 from the base I4 of the U. The base I4 is transversely4 cur-ved inwardly, that is, concavely curved, to add strength and rigidity thereto. The lower leg I3 is adapted to be laid upon the cross arm G, lengthwise thereof. The radius of curvature of the strap, lengthwise thereof, is chosen to provide ample nashover clearance (gap) between the conductor T and the strap.

The rearward end of the lower leg I3 is formed to present a bent-back portion I`I overlying the leg I3 and extending toward the base I4 oi" the U-shapecl member I I, in spaced parallel relationship to the leg' I3 to provide a support for the lower'end of the insulator IO.

To provide the support or portion Il, and as bestshown in Figure l, the rearward extension which provides the support, is bent upwardly as at I5, and then bent at an angle as at I8 from which the support .proper or portion I'I extends. By so forming the extension, more particularly, the portionIB, lthe distance between the usual tie wire W effectivelyattaching the conductor T tothe insulator II] is increased, to provide ample dash-over clearance.

The upper leg I`2 is so spaced from the support or portion II as to provide the space necessary to receive the insulator therebetween.

Straddling the lower leg I3 is an elongated member I8, conveniently formed or pressed from a metal strap or bar. The member I 8 is formed to present a recess I9 (see Figure 2) adapted to receive the lower leg I3 proper, and side, slightly inclined portions 2.6 adapted to engage part of the upper face of the cross arm, the side portions terminating in downwardly-directed'or dependingY iianges 2'I adapted to lie closely adjacent to the opposite vertical faces of the cross arm. Thus, when the elongated member Iand the leg member I3y are held againstone another by a bolt 25 (to be referred to later) both memf bers are held against substantiallateralmreltive displacement, and the Ufshaped member .II is also iheld against lateral displacement relatively .to the cross'arm as well as against rotary displacement on the axis of the bolt 25.

One end of: the elongated member I8 termi,- nates inan upwardly-curved portion 24 adapted to engage lpart .of the cur-ved lower portion of the base I4 of .the membery II effectively to ladd streng-th and rigidity Ato the member Ilfxnore particularly, to the curved lower end of the base I4. This arrangement makes for a simplified, and therefore cheaper, but sturdy device.

The legs I2 and I3, the elongated member I8 and the insulator support I1 are provided with aligned holes to receive a conventional cotter bolt 21 by which the insulator is attached in operative position to the mounting. The bolt is gaging, straddled relationship, and held to the cross arm, by the bolt 25 aforesaida carriage l bolt. The hole through the elongated member I8 for the square shoulder of the bolt 2 1Y is sov positioned relatively to the upwardly curved end 24 of the member I8, that the curved endis inv contact with the lower curved portion of the base I4 of the member II. The shank of the bolt is threaded throughout, to receive a nut 33, soi that the nut serves to hold the leg I3 and the elongated member I8 in tight engagement or con.

tact. The nut 33 may be generally tapered and made to a diameter slightly less thanvthe conventional tapered hole provided in cross arms 4for the reception of wooden pins. The mounting may thus be assembled and applied as a unit to thev cross arm, the unit being held in operative position as by a washer 36 and nut 3'I.

The nut 33 is generally tapered to be received tightly into the upper portion of the vertical hole through the cross arm. To facilitate the tightening of the nut in position, diametrically disposed wrench flats 38 are provided on the nut.

' Cross arms are sometimes provided with vertical holes adapted to receive steel insulator supporting pins, in lieu of Wooden pins. To adapt the mounting to the use of such a cross, the carriag'e bolt 25 and nut 33 may be replaced by a stud 40 such as shown in Figure 4. The studincludesan integral collar 4I and has its oppositeends threaded to receive an upper nut 42 and the nu`t 3`I and washer35 (shown in Figures 1 and 2). The nut42 and collar 4I operate to hold the elongated memberv I8 and the leg I3 together,` as well as operatively attached the mounting tothe cross arm-.that is, they have the function served by the carriage :bolt 25l and nut 38 aforesaid.

The carri-age bolt 25` (or the stud 40as the case L'may be) is positioned as far iawaywf'rom the end of the leg I3 as possible. When thedi-l rection of the conductor T changes at the in sulat'or; a very'- great pressure or force is im-f posed horizontally upon the insulatorl in a direction away-from the base I4 ofl theYU-shaped mounting II (ther-mounting is always attached to the cross larm so thatgthe force is' against. and not away from, theinsulator). The mount-l. ingtends to rotate with respect to the cross arm, longitudinally thereovon` thecuter, end (the right-hand eri'd'as seen in Figure l).oi the leg I3., VThe turningfmoment, beingpressure times the vertical distance between the conductor and theupper face V'of thefcross arm, isz-resisted by the Vturning moment defined by the distance between the outer end 'of the leg I3v and the axis of the bolt 25,. Thus, the greater such. distance is,` the less is the` tension imposed upon lthebolt. As under suoli-'conditions of deflectionaof ,the conductor at the insulator, a Vhorizontalforce is also imposed -upon Vthe leg I2, tending tade-v form the U -shaped 4member I I,' the curved rearrward extension 24 of the elongated member I8 to some extent resists the deformation of the U-shaped member or mounting.

It is to be understood that the term bolt in the claims is not to be a limitation of the scope of such claims but is to include any mechanical equivalent. f l f l AWhatI-claimis:

l. I n a cr-oss arm insulator mounting, a substantially U-shaped member one leg of which is in part flat to lie upon the cross arm, longitudinally thereof, said leg including a rearward portion overlyingsaid one leg in spa-ced relationship theretoman elongated member adapted to lstraddle saidone leg and prevent relative lateral displacement thereof, sai-d portion being spaced from the 'other leg of said U-shaped member to recelve the insulator therebetween and forming a support therefor, said elongated member terminating at one end in an upwardly .curved extension adapted to engage a lower curvedportion of the base of said U-shaped member, and a bolt for securing said elongated member and said one leg in straddled, coengaging relationship and to the cross arm, said .portion and at least said other leg having aligned holes forthe reception of the bolt by which the insulator is operatively attached to the mounting, said Vfirst named 'bolt being positioned nearer to said curved extension than theaxis of said aligned holes. V* o 2. In a cross arm insulator mounting. a metal strap longitudinally bent in tssubstantiaiiy the form of a U to present a pair of generally parallel .legs extending from the` base of the U, of which one leg is in part at and is adapted to be laid lengthwise upon the cross arm, said one leg terminating in a rearward portion extending i towar-d the base of the U in spaced parallelv rev lationship with said one leg tofformfa'support for the insulator when in operative position be# tween ksaidnportion and the other leg 4of said strap, the base of the U being concavelyfformed, a second metal strap of vgenerally channelled form -adaptedvto straddle sai-d oneV leg! and in part encompass the cross arm, said second 'strap terminating at one end in an `upwardly' curved extension adapted to engage a lower curvedportion of said base, and a bolt. securing said'one leg and said second member Yin straddled rela` tionship and adapted to pass through the cfss arm whereby to attach the mounting' thereto, said legs, said portion and said 'second'metal member having aligned holes for'the reception of the b oit attaching the insular-,arto themurit ing, s'a1d irst-named bolt being positioned'nearer to said base thanv the Aaxis of saidalgnedholes'. `'iraniani-t1orgGEQRGE RIDGERS;

" REFERNCES CITED --.The followingreferences arev of recor le ofgthisupatent:` n: UNITED STATES-PATENTS! Number Name Y" Date .I .1,138,701 Varney May 11,1915 1,479,155 Peirce f .1ani' 1. 1924 A2,302,383 yo1ivier, ,VNov. 24, 1942