US937897A

US937897A - Strain-insulator.

Info

Publication number: US937897A
Application number: US41022908A
Authority: US
Inventors: Theodore Varney
Original assignee: Westinghouse Electric Corp
Current assignee: Westinghouse Electric Corp
Priority date: 1908-01-10
Filing date: 1908-01-10
Publication date: 1909-10-26
Anticipated expiration: 1926-10-26

Description

T. VARNEY.

STRAIN INSULATOR.

APPLICATION FILED JAN. 10, 1908.

Patented Oct. 26,1909.

I'NVENTUR y BY [A], 4M

ATTORNEY WITNESSES 1 ("UNITED g li l A T I THEODORE VA'BNEY. or miniseries.-rEN'NsYLVANIAL 'issionon.BY'iunsn-rd essrons, MENTS', 'ro wns'rmenonsn ELECTRIC & ivranuriicrumno'.COMPANY: crease- PITTSBURG, PENNSYLVANIA, A CORPORATION or PE NSYLVANIA-1 s'rnn N- nsu'tn'roa. 7

I Specification of. Letters Patent lni (*lilttil (H'i .I. Application mediiiuiila 10.1908. Serial No. 410.2291] which may be poured in \tlien Lu-it and-"ale,

- and useful Improvement in Strain-lnsula- ;tors, ofwhich the following is a specifieatifon. I My invention'relates tostrain insulators for electric lines and it hasfor, its object "to 10 provide a compact and durableJdevice of j this character that shall bc'capable ofrwitlr standing str'ains incident to the use of high j voltages and that shall also embody an 1111- p port. the casing segments and hold them in proved easing of insulating material.-

tofore constructed, have sometimes comprised metal tubes having tapered ends into which insulating tubes and tapered plugs were fitted, the metal-tubes being surrounded by coatingsor'jacketsof molded insulating .material which extended. over the ends of the insulating tubes.

According to my present invention, I provide' an outer casing which is builtup of sections and which is so separated from the inner coating or jacket above mentioned that it is entirely freed from the strains to which the remainder of the insulator is subjected. The outer casing may be replaced by an other, when desired, and it serves to effec- Y tually protect the insulator proper from the weather.

' Figure 1 of the accompanying drawing is a partially sectional elevation of a strain insulator constructed in accordance with my invention and Fig. 2 is an enlarged view of the packed joint between the casing and the strain parts.

Referring to the drawings, the insulator here illustrated comprises a metal tube 1 having tapered ends, tapered tubes 2 and 3 of insulating material seated in the ends of the metal tube 1, tapered plugs a and 5 seated in the insulating tubes and provided with end projections 6' and 7 which extend for a material distance beyond the extremities of the insulating tubes, and strain loops High volta e strain insulators, as here- 12 and .13 of porcolaih orother hnird inst preferably formed of cast. iron \\:hicl.1. arew I 26, isms 1 plugs .4 and 5, may preferablyJiejlil h-dliw'i'lll:

asphalt gum, or other.insul nting,material.

lowed to sch-by cordingf-tfri o-rdiu'i peratures In order that a 'sti'll hetter,.1 be afforded zt'or the.entirc dea. c131.. a casing ll-comprisiug L\\ ';r ,taperedsections:

lating n1atcria],1:and end; caps; I14. and

fitted over-the shanks of the tapered :phi by stuffed oints and whichserve t'o. sup-a" position. -lhe vadjacent etvtren-iitiesi'of the" segments- 12 and 1 overlap-mud .a1'e am-.1 vided with opposite annular recesses '16 and 17 which together form an annular groove to be filled with cement for holding the parts together. The outer extremities of the

casing segments

12 and 13 are provided with annular grooves 18 over which the raps 1+ and 15 extend, the caps being secured in place by cement which fills the annular grooves 18 and the spaces between the caps and the segments.

The central portions of the caps are provided with hollow hub projections 15,) through which the shanks (land 7 extend and in which a suitable stulling or packing material is located, tight joints being formed by bushings 20 which are screwed into the hollow hub project-ions 19. Although tight joints are formed at the ends of the casing 11, the strains which are imposed upon the insulator proper are, not imparted to the casing. Asbestos washers 21 may preferably be 'i11terposed between the casing segments and the caps and also between the two segments.

8 and 9 which are screwed upon the eX- 1 stantlally changing the general construction tance between the plugs and the metal tube.

The iriterior of the insulator, between the The space within the casing 1-1 may be-filled with an insulating gum, or similar substance 10, which is sufiiciently yielding to permit of a slight relative movement between the outer casing and the strain parts.

\Vhile the tapered parts are all provided with conical surfaces, as shown in the drawings, it is conceivable thatmodifications in their contours may be effected without subor diminishing the usefulness of the insulator.

Variations in size and arrangement of parts may obviously be effected within the scope of my invention and I desire that only formed of metallic and insulating materials on which strains are exerted and a segmental easin therefor having sealed joints and comp etely inclosing said parts but relieved from the strains which are exerted upon said parts.

2. A strain insulator comprising a metal tube having tapered ends, tapered plugs seated in the ends of the tube and insulated therefrom and an inclosin casing therefor of hard insulating materia said casing bein relieved from the strains to which the ot er parts are subjected.

3. A strain insu ator comprising a metal tube having tapered ends, tapered tubes of insulating material seated in the ends of the metal tube, tapered plugs seated in the insulating tubes and having stems or shanks extending outwardly therefrom and a segmental casing of insulating material, the said casin being relieved from the strains to which t e other arts are subjected.

4. A strain insu ator comprising a metal tubehaving tapered ends, tapered tubes-0f insulating material seated in the ends of the metal tube, tapered plugs seated in the insulating tubes and having stems extending outwardly therefrom, a molded jacket of insulating material which seals the tube and extends from one stem to the other, and an independent outer casing which is free from the stirains to which the other parts are subjecte 5. A strain insulator comprising a metal tube having tapered ends, tapered tubes of insulating material seated in the ends of the metal tube, tapered plugsseated in the tapered tubes and having stems extending outwardly therefrom, strain loops attached to the stems, an insulating compound which fills the space in the metal tube between the plugs, a molded jacket of insulating material which seals the structure and extends from one stem to the other, and an independent inclosing casing therefor comprising a pair of overlapping tubular segments an end caps that form packed 'oints with the stems.

In testimony w ereof, I have hereunto subscribed my name this 20th day of Dec.,

THEODORE VARNEY. Vitnesses:

WILLIAM CooPnR, BIRNEY HINES.