US2209009A

US2209009A - Conductor clamp

Info

Publication number: US2209009A
Application number: US274155A
Authority: US
Inventors: John J Taylor
Original assignee: Ohio Brass Co
Current assignee: Ohio Brass Co
Priority date: 1939-05-17
Filing date: 1939-05-17
Publication date: 1940-07-23
Anticipated expiration: 1957-07-23

Description

July 23, 1940- J. J. TAYLOR CONDUCTOR CLAMP Filed May 17, 1939 mvENToR (Jo/m d Ta ATTORNYI VAatentec- July 23, Q

PATENT OFFICE CONDUCTOR CLAMP` .lohn J. Taylor, Wadsworth, Ohio, a.ssignor to The Ohio Brass Company, Mansfield, Ohio, a corporation of New Jersey Application May 17, 1939, Serial No. 274,155"

7 Claims.

" This'invention relates to supporting clamps for electrical conductors and particularly to pivoted clamps for ground wires such as are commonly usedin connection with high voltage electrical transmission lines. Heretofore ground wires have sometimes been supported in clamps rigidly fixed to the supporting structure for the transmission "1ine. Since the ground wires are usually at the Asame potential as the supporting structure, it `is not necessary to provide insulation between the wire-and its support and the clamp may therefore be xed directly on the supporting structure. A rigidlyflxed'clamp, however, has been found to produce fatigue in the fibers of the ground wire at' the points where the wire leaves the clamp. Thewire vibrates due to windage and other causesythe vibration being predominately in a i vertical direction, and since the wire is held rigidly at its support, the vibration produces bending andconsequently fatigue in the wire where it leaves the support. lToovercome this difficulty it has been proposed to mount the ground "wirein a'pivoted clamp, but where the clamp has been`mounted on a fixed pivot the vibration `of the wire has produced excessive wear on the pivoted support destroying the support in many Vcaseswithin ashort period of time. This wear is due not only to the vibration of the clamp about 1 its pivot,` but also to the frequent changes in the 'direction ofthe tension in the wire which gives y y "at rise'to slidingmovement of the support on its pivotwhere there is clearance between the pivot and the'bearing. It has been found in practice `thatthe direction of tension in the ground wire its point of support changes frequently due `to temperature differences and difference in wind velocities at opposite sides of the support. This is"particularly true where long spans are carried by the support.

Another expedient which has been tried to avoid fatigue and to allow response to the changes in the direction of tension in the wire is to mount the clamp on a link which has pivotal connection with `the clampat its lower end. This link, however, must necessarily be comparatively short to f avoid excessive distance between the ground wire 4and the top of the supporting tower, and a short link involves a comparatively large angle of movement in response to shifting tension in the ground wire'.` `In some instances the movement has been provide ample pivotal movement at the point of support and substantially eliminate wear of the supporting pivot.

A further object of the invention is to provide a pivotal support for a ground wire in which all of the movement at the pivotal support will be rolling movement and there will be no sliding movement between contacting faces.

A further object of the invention is to provide a conductor support having a pivot pintle which is easily assembled and disassembled and` which is enclosed in a housing to protect it from abrasive material in regions where such material may be carried bythe wind.

A further object of the invention is to provide a conductor support which shall be of improved construction and operation.

Other objects and advantages will appear from the following description.

The invention is exemplified by the combinaa port shown in Fig. l with a part of the rpintle housing sectioned on the line 2 2 of Fig. 3.

Fig. 3 is an end elevation of the conductor support with parts in section on line 3-3 of Fig. 2.

The conductor support is provided with a base Ill which may be bolted on any suitable struc-ture such as a tower for supporting a high potential transmission line. The base I0 is provided with upright spaced standards Il having bearing openings I2 in their upper ends. A conductor support is mounted on the standards II, the support comprising a cradle I3 for receiving the conductor and a keeper I4 for holding the conductor in place in the'cradle. The keeper i4 is held in place by means of U-bolts I5 which engage notches IS in the top of the keeper and which extend through openings I'I in lugs I8 at the sides of the cradle I3. The U-bolts are held in .place by nuts I9 threaded on their projecting lower ends. At each side of the cradle i I3 extending between and connecting the lugs I8 is a housing member 20 completely closed at its top and sides but open at its bottom to `receive the upper end of a standard II. The outer face of each housing 2|] is provided with a boss 2l having a cylindrical recess 22 on its inner face. The

inner wall of the housing 2@ is provided with a perforation Z3 in alignment with the recess 22, and the recesses 22 and perforations 23 register with the bearing openings l2 in the standards Il. Pivot rollers 2d. are loosely disposed within the bearing openings i2, 22 and 23; the rollers being of considerably less diameter than the openings I2, 22 and 23. The rollers are held in place by retainer lugs 21 projecting from opposite sides of the keeper it. The outer faces of the lugs 21 bear against the inner ends of the rollers 2li as indicated clearly in Figs. l and 3. y Y

In assembling the clamp, the base l@ is first secured on the supporting tower and the cradle placed between the projecting standards Il with the upper ends of the standards extending into the housings 2G. The roller bearings 2li are then inserted in place through the perforations 23 in the inner walls of the housings 20. The conductor 23 is then seated in the cradle i3 and the keeper piece lli secured in place by the U-bolts l5. This will bring the retainer lugs 2l into engagement with the inner ends of the roller bearings 24 and lock the bearings in position. It will now be apparent, particularly from Figs. 2 and 3, that the roller bearings 2li rest on the bottom of the openings l2 in the standards i l with a clearance space in these openings above the tops of the roller bearings. The cradle i3 is supported on the ends of the rollers 2li; the openings in the walls of the housing members 28 resting on the upper elements of the roller bearings 2d at the opposite ends of the bearing pins. Since the openings for the pins 24 are materially larger than the pins themselves, the cradle will be supported upon a single element of each pin, and any pivotal move. ment of the cradle when the weight is directly downward, will take place about this element of support and there will be no sliding of the contacting surfaces relative to each other. If, however, the tension in the cable tends to draw the cradle in either direction transverse to the axis of the pins 24, the pins will act as roller bearings between the surfaces of the bearing openings so that the elements or" contact will be progressively changed by the rolling action between the pins and their contacting surfaces until the elements of contact are in line with the new direction of the tension on the cable. The action is similar to that which takes place if one rolls a pencil over the top of a table beneath his palm. The pencil acts vas a roller between the two bearing surfaces and there is no sliding movement between the pencil and either of the contacting surfaces. A similar rolling action occurs between the pin 24 and its contacting surfaces, the only difference being that the contacting surfaces are curved instead of at. The action of the roller pin 2li may also be compared to that of the pinion in a set of planetary gears. Since there -is gno sliding movement between the bearing surfaces but only a rolling movement, there will be a minimum of wear although there is complete freedom of movement to permit vibration of the cable without bending at the points of support and to permit repeated shifting of the tension on the cable. In addition to the provision of pivotal `movement; without wear, the arrangement provides a supporting yclamp in which the pivotal supports are enclosed in a protective housing, and in which the parts may be readily assembled and dissembled and are locked in place merely by the clamping of the keeper piece in position upon the supported cable.

As seen in Fig. 3 the axis of the pins 24 is slightly above the center of the cable 28 at its mid point in order to bring the pivotal axis in line with the axis of the cable at the points Where the cable leaves the clamp. The direction of the pull on the clamp due to the tension of the cable is, of course, determined by the direction of the cable axis where it leaves the clamp and by arranging the pivotal axis 'in line with the cable pull, any tendency to rotate fthe clamp yon its pivot due to the tension in the cable is avoided.

I claim:

l. The combination with a conductor clamp Yhaving a bearing opening therein of a roller pin looselydisposed in said opening and of less diameter than s'aid opening, and a rigidly fixed support for said pin v*having a bearing opening in which a portion of said pin is disposed, the bearing opening in said support also being of greater diameter than the diameter of said pin, the difference in diameters of said pin and saidopenings being suiciently great that said pin Ihas free rolling contact with the surface of the bearing opening in said clamp and the surface of the bearing opening in said support when said clamp is moved relative to said support in a direction transverse to the axis of said pin.

2. The combination with a conductor clamp having a pair of spaced registering bearing openings therein, a rigidly lixed support Afor said clamp interposed between said openings and having a bearing opening therein in approximate registration with the openings in said clampfand a roller pin loosely disposed inthe openings in said clamp and extending through the opening in said support, said pin being of sufliciently less diameter than the openings in said clamp and said support to allow free rolling contact with the surfaces of said openings when said clamp is moved relative to said support in a substantially horizontal direction transverse to the axis of said pin. 4

3. A support for a conductor comprising a pair of cooperating bearing members, one of said members having a pair of spacedopenings therein, the other of said members being disposed Ibetween said openings and having a bearing 1open` ing cooperating with the openings in said .first bearing member, Vone of said .members being rigidly I'ixed and the -other -being horizontally and pivotally movable yrelative -to said Xed member,

and a roller pin disposed in said openings for connecting said members for pivotal movement relative to each other, said `roller pin being -of suliiiciently vless diameter than saidiopenings to allow free rolling contact with the vinner surfaces of said openings when said movable member is movedy horizontally relative to said fixed member.

4. The combination with a cable `'clamp of a plvotal support for said clamp, comprisingfa housing member having :a -closed top, and sidewalls,k

surrounding an internal recess and having bea-r-I ing openings in opposite side Walls thereof,one of said pivotal openings 'extending through its side wall to permit insertion of a pivot pin, -the 'other pivot opening being closed at i-ts outer-lend, a pivot bearing member extending into said housing member through the bottom portion thereof and having a bearing vopening therein in substantial registration with theopenings in thesides of said housing member, `anda roller pin-disposed in said openings-and of less-diameter than said openings and connecting said housing -and fsaid bearing member for relative pivotal movement, said openings all being substantially the same `diameter and said lpin being-of substantiallyiunilform diameter throughout and having free rolling contact= lia.

with the inner surfaces of said openings to facilitate relative shifting of said pin and members transversely of the axis of said pin by rolling engagement between the surface of said pin and the inner surfaces of said openings.

5. The combination with a conductor clamp having a conductor cradle and a keeper piece for securing a conductor in said cradle, of a pivotal support for said clamp having bearing openings and a roller pivot loosely disposed in said openings, said keeper piece being arranged to engage one end of said pivot and to retain said pivot in said openings when said keeper piece is in place in said clamp.

6. A conductor support comprising a rigidly X- ed base member having spaced uprights thereon, said uprights having bearing openings therein, a cable clamp comprising a cable cradle having laterally extending housing members for receiving `the ends of said uprights, said housing members having spaced bearing openings therein, pivot rollers disposed in the openings in said housing members and extending through the openings in said uprights, and a keeper piece for securing a cable in said cradle, said keeper piece having stops thereon for retaining said pivot rollers in position in said housing members, said pivot rollers being of sufciently less diameter than the openings in said housing members and said uprights to facilitate rollingV engagement between the surfaces of said pivot pins and bearing openings cooperating therewith when said clamp is shifted horizontally relative to its fixed support by different horizontal stresses on said conductor to facilitate relative shifting of said pivot rollers and bearing openings for stresses in dilerent directions on said conductor clamp.

. 7. The combination with a rigidly xed base, of a cable `clamp pivotally mounted on said base, the pivotal mounting between said base and clamp comprising one member having spaced portions provided with registering bearing openings therein, another member interposed between said spaced portions and having a bearing opening said openings, the openings in said members all being of substantially the same diameter and the pin being of substantially uniform diameter throughout, the diameter of said pin being materially less than the diameter of said openings so that said pin has a line contact with the surface of each of said openings and rolls on the surface of said opening when said clamp is moved in a direction transverse to the axis of said pin.

J OI-IN J. TAYLOR.

- therein anda bearing pin loosely mounted in l