US1806294A - Strain insulator - Google Patents

Description

y 1931; w. H. KEMPTON 1,806,294

STRKIN INSULATOR Filed April 6, 1927 Z /s Q 4w fiA /4 S /4 5 /2 WITNESSES: k9 INVENTUR h J/ara h Mempfd/z Patented May 19, 1931 UNITED STATES PATENT orrlc'n- WILLABJ) H. KEMPTON, OF WILKINSBURG, PENNSYLVANIA, ASSIGNOR TO WESTING- HOUSE ELECTRIC & MANUFACTURING COMPANY, A CORPORATION OF PENNSYL- VAN IA STRAIN INSULATOR Application filed Apri1'6, 1927. Serial No. 181,326.

I My invention relates to strain insulators, and particularly to strain insulators embodya ing interlinked metal parts.

One object of my invention is to provide an insulator of the above-indicated character vide a strain insulator that shall. have no curved or other parts likely to become distorted under strain.

Another object of my invention is to provide a strain insulator, embodying an in .sulating shell or cover, that shall be so'constructed as to avoid fracturing the shell under of the blocks 2 comprises a rectangular metal load conditions.

Another object of my invention is to provide a strain insulator that shall embody novel anchoring meansfor a molded insulate ing cover thereof.

In practicing my invention, I provide an insulator of such construction that certain of its parts may be suited to quantity production, by cuttingthem from bars; that permits ready assembly of its parts; that resolves its. 1 strains into straight lines to prevent fracans ture' of its insulation and is otherwise constituted to be a material improvement over in Fig. ,1,

Fig. 3 is aside view, partially in section and partially in elevation, of the structure shownin Figs. 1 and 2, taken at right angles to Fig. 2,

Figs. 4 and 5 are detail perspective views ofparts embodied in the insulator of the foregoing figures, and

Fig. 6 is a view, similar to Fig. 3, of a modified form of the invention.

Referring to Figs. 1 to 5, inclusive, the insulator comprises, in general, rectangular or oblong block elements 2, terminal member-s3, a loop or interlinking metal member 4 and a molded insulating cover member 5.

The block elements 2, together with the terminal members 3, constitute terminal structures of substantially T-shape, or oppositelyprojecting terminals having enlarged inner ends, in .which the enlarged inner ends or heads are disposed in substantially parallel relation and surrounded by the inter-linking member 4 through which the legsof the T- structure extend. i

As more clearly illustrated in Fig. 5, each core or anchor member 7 and a substantially tubular insulating cover 8 that is preferably molded in position and constructed of laminations or layers of paper or other suitable sheet insulating material impregnated with a hard molding material. As thus constructed, the

blocks 2 may be readily cut from relatively long bars ofthe rectangular metal cores on which the molded insulating cover 8 has been placed.

Before or after cutting the above-mentioned bars, holes or openingslO maybe drilled and tapped for the reception of screwthreaded shank portions 11 oftheterminal members 3. v i

The interlinking member 4 is of substantially tubular construction, whereby it may also be cut from greater lengths of such tubing, and is preferably of such rectangular cross-sectional area as to effect a neat sliding or press fit with two of the blocks 2.

The member 4 is further provided with oppositely disposed side openings 12 0f appreciably larger diameterthan the shanks 11 and has beveled edges 14 constituting holding or anchoring portions for "assisting in holding the molded insulating body or cover 5 in position.

In constructing the insulator, the blocks 2 are pressed or passed through an end of the sulating body or cover'5 .is molded in position,

During the molding operation, the mate rial of the body 5 is pressed into the spaces, in the openings 12, between the' member :4 and the terminalmembers 8. Al so,'b0sses '16 are formed'in the cover having notches 17 therein that cooperate with the ends of pins 18, extending through the terminal members 3, to prevent turning,or unscrewing, of the shanks 11 from the blocks 2.

In the above-described structure, only 'th sides of the cores 7 are covered by thelaminated insulating bodies 8, the ends of the core members and the entire'insulator being covered by theinsulatingbody' 5. This feature provides insulation that is, very strong mechanically and electrically,

tive insulating protection for the'insulator in a simple, economical manner.

f Also, in the above described structure, the

hat right angular relation of'the' stressed Iparts eliminate the collapsing tendency of curved parts in'strain devices of this character. This tendency results in fracture and dislocation of'the parts, vparticularly of the insulation which is thereby very readily rendered unfit for service and causes breakdown of the insulator.

, 'In my device, the insulating bodies 8 are substantially in straight compression, and

V the'insulating cover 5 is practically freeof mechanical stresses of any kind. I

In the modification ofmy invention shown in Fig. 6, in which corresponding parts are designated by corresponding reference char actors, the construction ,is substantially the I, same'as' that above described, eX'ceptf thatthe different form and: an entraplate or body "20 of insulation is placed betweenthebloc'ks openings lOare drilled'through the blocks 2, the anchoring portions 14 are of slightly The plate20 is preferably of laminated form, similar 'to the insulating covers 8 in the blocks 2. V

The anchoring portion 14,," instead of i being along the end edges of the member 4, as shown are disposed along the longitudinaledges from which they each so project in two directions as to assistin hold- 'ing the rightangularly related sidesof the,

cover 5 in position;

Modifications and rearrangements of the portions 14: maybegmade-to hold the molded. cover '5 in any desired'm'anner.

tubular metal member and said terminal portions and about said parts.

V where such "in 'sulation is most needed, and a general efi'ec By my invention, a strain insulator is provided that, besides being of extremely compact, durable and effective character, facilitates and economizes its manufacture and has other features of improvement over insulators heretofore employed.

While I have shown and described par-' ticular forms of my invention, changes may be eilected therein without departing from the spirit and scope thereof, as set forth in the appended claims. A

k I claim as my invention:

1. A strain insulator comprising rectangular *block elements, including rectangular metal core members and laminated rectangulartubular insulating coverings thereon,-disposed in adjacent flat-surface relation, a rectangular tubular metal membersurrounding the elements, terminal portions I projecting from the core members through said coverings and through said tubular metal member in spaced relation to the latter, and-a of insulation molded in the spaces btweenthe 2. A strain insulator comprising rectangular block -elements, nclud1ngrectangular metal core members and rectangulartubular insulating' coverings thereon, disposed "in adjacent flat-surface relation, e s for holding the elements to each other and terminal-portions projecting from the core members.

3. Astrain insulator comprisingirectangw 'lar" block elements, including rectangular metal core members and laminated tubular insulating coverings of rectangularoross section molded thereon, disposed in adjacent fiat-surface relation, a tubular me'tal element of rectangular cross-section surrounding the elements, terminalmembers including shanks screw-threadably mounted in said-=core members projecting therefrom through said cov erings and through said tubular metal memher in spaced relation tothelatter, and abody of insulation molded inthe spaces between the tubular metal member and said shanksand about said parts.

4. A strain insulator including tubular insulating portions disposed in side by-side relationtransversely to the tension" load,"

anchor members in said tubular portions, a

tubular element surrounding said tubular portions in substantially parallel relation thereto and terminal portions projecting through said tubular element .'from said" anchor membersinthedirection of .said load.

5. A strain insulator including tubular insulating portions disposed in side-by-side relation transversely to the tension load,

metal anchor members in said tubular por tions, a tubular metal'element surrounding said tubular insulating portions in substantially parallel relation thereto .and k-metal terminal portions projecting fromfsaidan chor members in the direction of saidload through said tubular insulating portions and through said tubular metal element in insulated relation thereto.

6. An insulator including tubular insulating portions disposed in side-by-side relation,

metal anchor members in said tubular portions, a tubular element surrounding said tubular portions in substantially parallel relation thereto and terminal portions projecting through said element from said anchor members transversely to the axis of said tubular element.

7. An insulator including tubular insulating portions disposed in side-by-side relation, v

, a tubular element surrounding said tubular portions in substantially parallel relation thereto and terminal means having anchor portions in said tubular portions and portions extending through said element transversely to the axis thereof.

8. An insulator including tubular insulating portions disposed in side-by-side relation, metal anchor members filling said portions flush with the ends thereof, a tubular metal element surrounding said portions in substantially parallel relation thereto and having transverse wall openings, metal ter- 'minal portions of smaller diameter than said openings projecting therethrough from said anchor members and a body of molded insulating material covering the insulator and disposed in said openings about said terminal portions.

9. An insulator including tubular insulata ing portions disposed in side-by-side relation and having transverse side openings, metal anchor members in said portions having screw-threaded openings opposite said side openings, a tubular metal element surrounding said portions in substantially parallel relation thereto and having transverse wall openings opposite said side and screw-threaded openings and metal terminal members having screw-threaded portions in said screwthreaded openings and portions projecting through said transverse wall openings in spaced relation to said element.

In testimony whereof, I have hereunto subscribed my name this 31st day of March,

so 1927. I

WILLARD H. KEMPTON.

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