US2008342A - Insulator - Google Patents

Description

U O E T.. S L. Q

INSULATOR Original Filed Aug. 14, 1951 Patented July 16, 1935 UNITED Param ori-'fics to `AJeffery `-Dcu'ril'lt Insulator .Campana Kenovm W. 4.V.a .,.,a.. corporation of West `Virginia IReled ffor .abandoned application, -Serial No.

2557;,186, August 14, 1931. iThisanplication'De- 17 '1335, Serial No. 756,538

-This invention is agsuspensiontype-insulator of the character employed Vin connecticn with high 'tension electricaly transmission.

One of the objects of the invention vistoprovide 5 an insulator which will'not pull apart ,below its full breaking strength, even: though the porcelain or other dielectric Abecomes, cracked. ordamaged. A vfurtherobject is to utilize thick porcelainnto provide great -resistance :to yshattering 1 by .power l arcs, missiles, and rough handling, before erection,

and the like.

The invention will be hereinafterfully set Aerth and particularly pointed out in theclaims.

In the accompanying drawing:-

Fig. v1 is a side elevationzillustating an insulatorV constructed in Aaccordance with the 1 vinvention. Fig. 2 is a vertical Asectional vieWthereof.

Referring to thedrawing-Adesignates lan insulator body constructed of porcelainror other similar dielectric. rAs shown, saidzbodyfconsists of va relatively massive skirt g IIL-.harlingenintermediate ilat topped portion I I, from whichiprojects ,a centrally disposed axially extended portion I2, preferably of approximately hemispherical form. It will be noted that the axially extended portion I2 is of approximately circular cross section with its maximum diameter at its intersection with the top of the skirt I0, and terminates in a rounded extremity. By this construction, the entire dielectric body is free of peripheral grooves and depressions which would normally tend to weaken the mechanical strength of the dielectric body. The intermediate flat surface II is provided with a plurality of recesses I3 equally spaced, so as to receive the correspondingly spaced legs I4, of a metal supporting cap I5. Said cap may be made of any suitable or desired metal, but cast steel is preferred. In addition to the legs I4, said cap is provided with the recess I6 for engagement with the complementa] head I1, of a pin I8, of an adjoining insulator unit. It will be noted that the body of the cap I5 is dome shaped, so as to nt over the upwardly projecting portion I0. As shown in the drawing, the cap I5 does not conform precisely to the contour of the projection I0, and the space between the two is filled by any suitable resilient compound I9, in a manner well understood in the art.

The walls of the recesses I3 are preferably coated with any desired water proofing material well known in the art, and the legs I4 of the cap I5 are anchored in said recesses in any desired manner. It is preferred, however, to retain the legs in position by means of an alloy of lead and antimony, which can -befapplied ,while in :a lmolten condition.

v The-pin .t8 may be of any desired construction, and'fis'inscrted within a complemental recessl formed inthe underside of .the insulatorbody. `5 Saidz-pin is ,provided :with annular shoulders 12, as `Shoji/nso `that it maysbe frmlyanchored by suitablefanchoringmaterial 123.. vIt `will be noted thahthewall of the Arecessis-,also ,provided with annular shoulders24, so yas to retain :the anchoring 'rnaterial in place. Any desired `anchoring material maybe employed,butitfisfpreierred to useft-he :alloy of lead-and vantimonyabove referred to. -In allinstancesof thelise of theanchoring alloy, allzjoints betwcentheralloy and the dil electric are sealed against moisturewhichxni-ght freeze, yby :applying waterproofing after. assembly.

AAn4 :important advantage of the above described construction is that. thelegs ltoffthe cap I-5:extend:downwardly-well below the inner end of the-pinfl, and that the recess 2| is so deep-'that it fextendswell intothe ycenter ofthe projection Ipsothatwthe inner extremity-of f the pin fIB is well above the plane of the intermediate surface II, the legs and pin lying parallel but in somewhat overlapped relation. By this construction, the mechanical stresses are carried by the dielectric body in shear and compression, rather than in tension, as is customary in the suspension type insulator. A further advantage is that a large proportion of the axial length of the insulator is covered by the metal cap, thus reducing the tendency to cascade a string of insulators, i. e., the arc will not jump into the hardware and out again to the porcelain, as commonly occurs, but will make a curved smooth sweep from end to end of the string of insulators. It will be further noted that the legs require only small holes in the massive porcelain body, thus preserving the ruggedness of the insulator as compared with cup shaped caps. The massive skirt has the great advantage of resisting shattering when touched with intensely hot arcs or struck by missiles, and it also withstands rougher handling during transport and installation, and this mechanical strength is greatly enhanced by the integral axially extended portion with its maximum cross section at the intersection of the axially extended member with the top surface of the skirt portion of the insulator body. A further advantage is the mechanical reliability of the structure, because the legs of the cap go far below the inner extremity of the pin. Therefore, in case of a defective porcelain becoming cracked, the conductor will be held up by the vmetal parts until the defective unit can be replaced.

This case is a substitute for application Serial Number 557,186, filed August 14, 1931.

Having thus explained the nature of the invention and described an operative manner of constructing and using the same, although without attempting to set forth all of the forms in which it may be made, or all of the forms of ,its

use, what is claimed is:-

1. An insulator of the character described comprising a dielectric body consisting of a circular skirt portion and an integral axially disposed portion extended from the top surface of said skirt portion, said axially disposed portion being of approximately circular cross section with its maximum diameter at its intersection with said top surface, a series of spaced apart recesses being formed in said top surface and surrounding said axially extended portion, a dome-like metalcap extending over the end portion of said axially extended member and having its edge spaced from the top surface of said lskirt portion, said edge having dependingintegral legs complemental to and extended into the respective recesses, a centrally'disposed suspension pin inserted into the bottom portion'of'said body, the lower extremities of said-legs extending to a plane well below the inner extremity of said pin, so that the mechanical stress will be ycarried by the dielectric material in shear and compression, and means for anchor ing said legs and said suspension pin.

' 2. An insulator of the character described comprising a dielectric body consisting of a circular skirt portion and Aan integral axially disposed member extended from the top surface of said skirt portion, saidv top surface being provided with an annular fiat surface encircling the base of said axially extendedfmember, the maximum diameter of said axially disposed member being at its intersection with said flat surface, recesses being formed in said flat surface and arranged in spaced relation surrounding the axially extended member, a dome-like metal cap extending over the end portion of the axially extended member and having its edge spaced from said nat surface, said edge having depending integral legs complemental to and extended into the respective recesses, an axially disposed suspension pin inserted into the bottom portion of the dielectric body, the lower extremities of said legs extending to a plane well below the plane of the inner extremity of said pin, so that the mechanical stresses will be carried Ybythe dielectric material in shear and compression, and means for anchoring said legs and said suspension pin.

*A 3. An'insulator of the character described comprising a dielectric body consisting of a circular skirt ymember and an integral axially disposed lmember of circular cross section, said axially disposed member extending from the top surface of the skirt portion with its maximum diameter at its intersection with said top surface, a plurality of spaced apart recesses being formed in said top surface and arranged in spaced relation around said axially extended member, Va dome-like metal capenclosing the end portion of said axially extendedk member and provided with a skirt,` the edge of which is somewhat larger in diameter than said axially extended member, said edge being spaced from the top surface of the skirt portion and provided with depending integral legs complemental to and extended into the respective recesses, said cap and said axially extended member being constructed and arranged to provide an intervening annular space of tapered cross `section, a resilient composition filling said annular space, an axially disposed suspension pin inserted intothe bottom portion of said body, the lower ends of said legsextending to a plane Well below the plane of the upper extremity of said pin, so that the mechanical stresses will be carried by the dielectric material in shear and in compression, and means for anchoring said legs and said suspension pin. f i CHARLES L. STROUP.

Images