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US885678A - Insulator for heavy currents. - Google Patents

Insulator for heavy currents. Download PDF

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US885678A
US885678A US29799106A US1906297991A US885678A US 885678 A US885678 A US 885678A US 29799106 A US29799106 A US 29799106A US 1906297991 A US1906297991 A US 1906297991A US 885678 A US885678 A US 885678A
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insulator
supporting
conductor
strain
pins
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Louis Steinberger
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    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02GINSTALLATION OF ELECTRIC CABLES OR LINES, OR OF COMBINED OPTICAL AND ELECTRIC CABLES OR LINES
    • H02G7/00Overhead installations of electric lines or cables
    • H02G7/20Spatial arrangements or dispositions of lines or cables on poles, posts or towers

Definitions

  • My invention relates' to insulators, and admits of general use, but embodies certain novel features of especial ser vice to be used in insulators for heavy currents and for long' spans between poles or towers.
  • rFlic tendency at the present day along lines of electrical development is to use larger insulators high dielec ossessing very tric qualities.
  • Tiiis Calls for greater rigidity in the construction of the insulator in order that the support afforded for the insulator and the wire or cable may be adequate for the pur ose and that the insulator may possess su cient stability.
  • an insulator may be provided with the requisite strength and the requisite dielectric qualities, without excessive weight or undue waste of material, and because of the rigidity and stability secured in improving the insulation, the insulator acquires properties which are of a special value in the matter of supporting the strain of cables or wires.
  • my improved insulator a firm and substantial support for sustaining the insulator so as to distribute the mechan ical strains upon it; 2. to )rovide a maximum ol' dielectriiI or. insulating ell'ectwith a minimum of weight and a minimum of material employed in construction; 3.to enable the insulator to be readily removed from its support; 4. to provide an improved means for yholding the wire upon the insulator; 5, to providespecially arranged spaces for receiving cables or other liexible members which may pull sidewise upon the insulator; 6. to enable lighter supporting members to be used by multiplying the number thereof;
  • cable may be applied to or yremoved fromfthe insulator; 8. to provide improved meansfor preventing undue movement of the wire or cable relatively to the insulator; 9. to give each wire or cable a. comparatively ,long
  • FIG. 2 is a vertical section through the same', upon the line 2-2 of Fig. 1 looking in the direction of ,the arrow, and showing in addition two cables dead-ended in op )osite directions from the insulator and insulated from each other;
  • Fig. 3 is a horizontal section, upon the line 3%-3 of Fig. 2 looking in thedirection of the arrow, and showing the insulator as it appears when viewed from its under side;
  • Fig. 4 is a fragmentary perspective view showing the insulator as mounted upon the twin cross arms, and Fig. 5 is device for engaging the conductor.
  • the supporting pole is shown at 5, anddisposed upon opposite sides of it are twin cross arms 6 clam )ed ktogether through the pole by means of bolts 7 provideihwith nuts Stor the purpose.
  • Twin pins 9 are provided with.
  • ⁇ stems 11 the latter passing verticallyv through the twin cross arins.
  • washers 12 held in position by-nuts 13, the latter being clam ed b nut-locks 14.
  • Each pin 9 is provided with an annular boss 1() integral therewith and serving as a shoulder. The upper ends of l the pins 9 terminate in smooth stems15 upon which the insulator body 16 makesv a neat fit.
  • This insulator body is provided with a plurality of hoods 17, 18 and 19 of different sizes, the llargest being at the top and the smallest at the bottom as shown in Fig. 2.
  • Integral with the hood 19 and with the insulator body 16 is an oblong skirt 2O which ena plan view of a clampingl Aso below the stems 15.
  • the insulator body 16 is hollow and is provided with a lweb 21 crossed by webs 22 integral therewith, as indicated in Figs. 2 and 3. These webs serve as braces or supporting ribs and prevent crushing or distortion of the insulator in case the latter is subjected to excessive strains.
  • the upper end of the insulator body 16 terminates in a comparatively longlhead 23 and encircling this head is a groove 24.
  • a groove is dis osed longitudinally of the head and bisectsitihe samegas indicated in Fig. 4, and this groove is crossed by a shorter groove 259'.
  • Either groove 25 or 25a may be used for receiving the wire or cable.
  • Each clamping member 26 is provide with fingers 27 carried by a supporting plate 26, the whole being made oflnalleable metal, such as, iron or bronze.
  • bolts 28 By means of bolts 28 the two clampingmembers are se ⁇ cured together. These bolts pass through opposite portions of the endlessgroove and blnd the twin members together.
  • Two cables 29, 30 that are disposed between the hoods 17, 18, 19 may be secured to the insulator and thusbe dead-ended in opposite directions from the strain, as indicated 1n Fi 2. That is to say, the cable 29 serves to pu l the insulator in one direction, whereas thecable 30 tends to pull it in the opposite direction, the movement of one cable op osing, or partially opposin that of the ot er, so that little or no ad itional strain is placedupon the su porting pins 9 because of theA presence oft ese4 cables. l
  • the wire 31 is artially buried within the groove 25 Iand is slightly curved, as indicated in Fig.
  • the fingers 27 of the twin clamping members 26 bein bent downwardly so as to grip the wire and old it in the position indicated in Fig. 2..
  • the part of the wire immediately within the groove 25 is slightly curved, as indicated in Fig. 2, andthe wire 1s thus held securely in positlon.
  • the Insulatorv as viewed from above isthat of a rectangle.
  • This shape is advantageous, for the reason that by it the insulation afforded by the body of the insulator stretches acrossthe twin cross arms 6 in such manner as to project beyond these cross arms and thus more completely protect the same.
  • the webs 22 by strengthening the interior of the insulator tend to revent the effeet of crushing strains applied by means of either of the cables 29 and 30 or the wire 31; that is to say, if either of these cables or the wire draws upon the insulator so hard as to set up within the insulator a crushing strain, this strain is counter-acted by the webs 22, as will be understood from Fig..2.
  • the spaces between the hoods 17 18 and 19 serve excellently for receiving cables to be dead-ended, or for carrying cables or wires around corners or curves, thereby admitting the use of this form of insulator as a combined line and strain insulator.
  • An insulator comprising a hollow member of insulating material provided with a portion for sustaining a wire, and also provided with ,Webs whereby saidmembenis strengthened, and a plurality of supports connected Jwith said member and spaced apart.
  • An insulator comprising a hollow memlber of insulating material provided intersai plins l 6. he c ombination of a pole,
  • An insulator comprising a pair of twin -cross arms, means for supporting said cross arms apart from each-other, a pin mou-nted upon each cross arm, a body of insulating material engagin Ysaid pins, and means for su porting a con uctor upon said body of insu ating material.
  • An insulator comprising a member of insulating material provided with means for sup ortin a conductor and also provided wit a we and a pair of Vpins connected with said member and spaced apart in a direction parallel with the plane of said web for the pur ose of distributing to it the strains upon twin cross arms clamped upon opposite sides thereof, twin supporting pins mounted upon said cross arms, and a sin le body of insulating material engaging sai twin-supporting pins and provided'rwith a portion for engaging a conductor.
  • a clamping member com rising two separate portions, each provi ed with gri ping iingers for clasping a conductor, an mechanism connected with said portions and provided withmeans for gripping an insulator body independently of the enga ement of said fingers relatively to said conductor.
  • An oblong insulator having its greatest length in the .irection of the length of the conductor to be supported and formed with a groove for the conductor, said groove extending at the top of the insulator in the direction of length of the latter, and separate supports at'the Dottoin of supports being s length of the insu ator and located at points in vertical line with points adjacent theends of the longitudinal groove'for the conductor.
  • An oblong insulator having its greatest'length in the direction of the length of the conductor to be supported, and formed with insulating material mountthe insulator, the. aced in direction ot the;
  • La groove for the conductor said groove extending at the top of the insulator in the direction of length oi the latter, and separate supports at the bottom of the insulator, the supports being s aced in direction of the length of the insu ator and located at points in vertical line with points adjacent the ends of the longitudinal groove for the conductor, the insulator further having a skirt at the bottom, of a shape following the general oblong sha e of the insulator and extending around t ie said separate bottom supports in common.
  • An oblong insulator having a conductor su thidirection of the greatest length of the port extending ⁇ along the insulator in latter, and separate supporting members for said insulator, the supporting members being spaced in the direction of the length of the insulator.
  • An insulator having commodating dead-end cab opposite directions, said insulator having supporting pins spaced from each other in the line of strain and located respectively adjacent to the points of contact of the respective cables.
  • An insulator having .i supporting porsaid portion being elongated in the direction of the length of the conductor, and separatepins supporting the insulator, said pins Ibeing located in line with eachother in the direction of the length of theconductor and being located adhaving a portion forenyjacent the ends of the said supporting portion for the conductor.
  • y 15 As an article of manufacture, an insulator having a portion for receiving a conductor, and having a plurality of supporting pins spaced from 'each other and arranged in the line of and perpendicular to the direction of the conductor.
  • An insulator comprising a body por? tion provided with means for sustaining a conductor, and a plurality of pins supporting said body portion and disposed substantially in alinement relatively to vsaid conductor.

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  • Insulators (AREA)

Description

No. 885,678. PATENTBD APR. 21,' 1908. l L. STEINBBRGER.
INSULATOR FOR HEAVY CURRENTS.
APPLICATION FILED JAN.26. 1906.
@sums-SHEET 1.
18o-885,878. PATENTIID APR. 21, 190s.
L. STBINBBRGER.
INSULATOR FOR HEAVY GURRBNTS. APPLICATION FILED IAN. 26; 190s.
. 2 SHEETS-SHEET z.
.By l
ATOHNEYS LOUIS STEINBERGER, OF NEW YORK, N. Y.
INsULA'roR Foa HEAVYy CURRENTS.
Application filed January 26,
To all whom it may concern:
Beit known that I, LOUIS STEINBERGER, a citizen'of the United States, and a resident of the city of New York, borough of Brooklyn,A in the county of Kings and i York, have invented a new and Improved Insulator for Hea Currents, of which the following is a ful clear, and exact description. i
My invention relates' to insulators, and admits of general use, but embodies certain novel features of especial ser vice to be used in insulators for heavy currents and for long' spans between poles or towers.
rFlic tendency at the present day along lines of electrical development is to use larger insulators high dielec ossessing very tric qualities. Tiiis Calls for greater rigidity in the construction of the insulator in order that the support afforded for the insulator and the wire or cable may be adequate for the pur ose and that the insulator may possess su cient stability. In securing the necessary rigidity and Stability, however, there is iiioi'e or less tendency to make the insulators too heavy and'cumbersome to be readily handled and also too expensive because of the excess ol' insulating material employed-.
l find that an insulator may be provided with the requisite strength and the requisite dielectric qualities, without excessive weight or undue waste of material, and because of the rigidity and stability secured in improving the insulation, the insulator acquires properties which are of a special value in the matter of supporting the strain of cables or wires. l
Among the objects which I attain by my improved insulator are the following: 1. a firm and substantial support for sustaining the insulator so as to distribute the mechan ical strains upon it; 2. to )rovide a maximum ol' dielectriiI or. insulating ell'ectwith a minimum of weight and a minimum of material employed in construction; 3.to enable the insulator to be readily removed from its support; 4. to provide an improved means for yholding the wire upon the insulator; 5, to providespecially arranged spaces for receiving cables or other liexible members which may pull sidewise upon the insulator; 6. to enable lighter supporting members to be used by multiplying the number thereof;
r., r i. to iacilitate rho case with which a wire or Specification o! Letters Patent.'
State of New y Patented Api-11 21, 190s.
190e. serai Nogzsvesi.
cable may be applied to or yremoved fromfthe insulator; 8. to provide improved meansfor preventing undue movement of the wire or cable relatively to the insulator; 9. to give each wire or cable a. comparatively ,long
stretch of 'surface upon which to rest; and 1,0.,'to provide internal braces for the insulator so as to reduce" the weight without proportionately reducing the strength thereof. 11. to rovide greater, security and better facilities for the lineman when placing the insulators andv ycables into operative ositions, repairing them, or removing them iioin the poles.` n Reference `is to be had to the accompany-I ing drawings forming a part of this specification, in which similar characters of reference indicate 'corresponding parts in all thefigures. Figure 1 is a fragmentary plan view show'- ing an insulator mounted upon twin cross arms 6 and supporting a wire; Fig. 2 is a vertical section through the same', upon the line 2-2 of Fig. 1 looking in the direction of ,the arrow, and showing in addition two cables dead-ended in op )osite directions from the insulator and insulated from each other; Fig. 3 is a horizontal section, upon the line 3%-3 of Fig. 2 looking in thedirection of the arrow, and showing the insulator as it appears when viewed from its under side; Fig. 4 is a fragmentary perspective view showing the insulator as mounted upon the twin cross arms, and Fig. 5 is device for engaging the conductor. f
The supporting pole is shown at 5, anddisposed upon opposite sides of it are twin cross arms 6 clam )ed ktogether through the pole by means of bolts 7 provideihwith nuts Stor the purpose. Twin pins 9 are provided with.
`stems 11 the latter passing verticallyv through the twin cross arins. Disposed below the twin cross arms 6 are washers 12 held in position by-nuts 13, the latter being clam ed b nut-locks 14. Each pin 9 is provided with an annular boss 1() integral therewith and serving as a shoulder. The upper ends of l the pins 9 terminate in smooth stems15 upon which the insulator body 16 makesv a neat fit. This insulator body is provided with a plurality of hoods 17, 18 and 19 of different sizes, the llargest being at the top and the smallest at the bottom as shown in Fig. 2. Integral with the hood 19 and with the insulator body 16 is an oblong skirt 2O which ena plan view of a clampingl Aso below the stems 15. The insulator body 16 is hollow and is provided with a lweb 21 crossed by webs 22 integral therewith, as indicated in Figs. 2 and 3. These webs serve as braces or supporting ribs and prevent crushing or distortion of the insulator in case the latter is subjected to excessive strains. The upper end of the insulator body 16 terminates in a comparatively longlhead 23 and encircling this head is a groove 24. A groove is dis osed longitudinally of the head and bisectsitihe samegas indicated in Fig. 4, and this groove is crossed by a shorter groove 259'. Either groove 25 or 25a may be used for receiving the wire or cable. Mounted within opposite ortions of the groove 24 are two oppositely isposed twin clamping memi bers 26, preferably exactly alike, as indicated in Fi 5. Each clamping member 26 is provide with fingers 27 carried by a supporting plate 26, the whole being made oflnalleable metal, such as, iron or bronze. By means of bolts 28 the two clampingmembers are se` cured together. These bolts pass through opposite portions of the endlessgroove and blnd the twin members together. By Giving the twin clamping members a proper degree of resilience, undue strain upon the insulating body s-up orting the head 23 is revented, and the atter is not so apt to he broken off. Two cables 29, 30 that are disposed between the hoods 17, 18, 19 may be secured to the insulator and thusbe dead-ended in opposite directions from the strain, as indicated 1n Fi 2. That is to say, the cable 29 serves to pu l the insulator in one direction, whereas thecable 30 tends to pull it in the opposite direction, the movement of one cable op osing, or partially opposin that of the ot er, so that little or no ad itional strain is placedupon the su porting pins 9 because of theA presence oft ese4 cables. l The wire 31 is artially buried within the groove 25 Iand is slightly curved, as indicated in Fig. 2, the fingers 27 of the twin clamping members 26 bein bent downwardly so as to grip the wire and old it in the position indicated in Fig. 2.. By this means the part of the wire immediately within the groove 25 is slightly curved, as indicated in Fig. 2, andthe wire 1s thus held securely in positlon.
It will be noted that the web or supporting. rib 21 reaches to a comparatively low point in com arison to the supportingplns 9. Thisl not on y strengthensthe insulator to a great extent butiimproves the insulation thereof, for the reason that if an arc should take place from the Wire 36 to one of the supporting pins it cannot readily pass therefrom to the other supporting'pin. Each pin 9 is rovided with a rounded shoulder 9'* upon W `ch a considerable parto the weight of theinsulator rests. i Y
ine generar coiuormlty 0I the Insulatorv as viewed from above isthat of a rectangle. This shape is advantageous, for the reason that by it the insulation afforded by the body of the insulator stretches acrossthe twin cross arms 6 in such manner as to project beyond these cross arms and thus more completely protect the same.
The webs 22 by strengthening the interior of the insulator tend to revent the effeet of crushing strains applied by means of either of the cables 29 and 30 or the wire 31; that is to say, if either of these cables or the wire draws upon the insulator so hard as to set up within the insulator a crushing strain, this strain is counter-acted by the webs 22, as will be understood from Fig..2.
The spaces between the hoods 17 18 and 19 serve excellently for receiving cables to be dead-ended, or for carrying cables or wires around corners or curves, thereby admitting the use of this form of insulator as a combined line and strain insulator.
It will be apparent that the two pins 9 are directly inthe line of strain, being spaced from each other in the direction of the strain ofI the cables 29 and 30, and the same with' respect to the conductor wire 31; thus an un ue strain exerted on the insulator, for
instance by 'the cable 29, is resisted directly' by the pin adjacent to the point of strain, and also by the in to the right. On the other hand, a s tram exerted by the cable 30,
is directly resisted by the pin 9 at the rightl .the point of strain, and indirectly by the pin distant from the point of strain. Furthermore, by thus dividinlrand distributin the supporting elements, faim enabled to o tain increased dielectric results, since arcing is guarded against, without making the insulator of a size and mass that would be necessary for equal results with a single pin.
I do not limit myself to the particular form of insulator herein shown, lnor to the exact form or number (2) ofeither of the separate members, nor to the use of any particular .material I prefer however, to employ the insulating material known inthe art as electrose Having. thus described my invention, I
claim as new and desire to secureby Letters Patentti 1. An insulator, comprising a hollow member of insulating material provided with a portion for sustaining a wire, and also provided with ,Webs whereby saidmembenis strengthened, and a plurality of supports connected Jwith said member and spaced apart. l
2. An insulator, comprising a hollow memlber of insulating material provided intersai plins l 6. he c ombination of a pole,
nally with webs, supporting pins'engaginrr said hollow member of insulating materia and mounted upon opposite sides of said webs, and means for mounting an'electrical 4. An insulator, comprising a pair of twin -cross arms, means for supporting said cross arms apart from each-other, a pin mou-nted upon each cross arm, a body of insulating material engagin Ysaid pins, and means for su porting a con uctor upon said body of insu ating material.
5. An insulator, comprising a member of insulating material provided with means for sup ortin a conductor and also provided wit a we and a pair of Vpins connected with said member and spaced apart in a direction parallel with the plane of said web for the pur ose of distributing to it the strains upon twin cross arms clamped upon opposite sides thereof, twin supporting pins mounted upon said cross arms, and a sin le body of insulating material engaging sai twin-supporting pins and provided'rwith a portion for engaging a conductor. f
7. In an insulator, the combination of a plurality of cross arms, means for supporting the same, a lurality of supporting members, a body portion of ed upon said supporting-members, and means for supporting a conductor upon said body portion.
- 48. As an article of manufacture, a clamping member com rising two separate portions, each provi ed with gri ping iingers for clasping a conductor, an mechanism connected with said portions and provided withmeans for gripping an insulator body independently of the enga ement of said fingers relatively to said conductor.
9. An oblong insulator having its greatest length in the .irection of the length of the conductor to be supported and formed with a groove for the conductor, said groove extending at the top of the insulator in the direction of length of the latter, and separate supports at'the Dottoin of supports being s length of the insu ator and located at points in vertical line with points adjacent theends of the longitudinal groove'for the conductor.
10.` An oblong insulator having its greatest'length in the direction of the length of the conductor to be supported, and formed with insulating material mountthe insulator, the. aced in direction ot the;
tion engaging the conductor,
La groove for the conductor, said groove extending at the top of the insulator in the direction of length oi the latter, and separate supports at the bottom of the insulator, the supports being s aced in direction of the length of the insu ator and located at points in vertical line with points adjacent the ends of the longitudinal groove for the conductor, the insulator further having a skirt at the bottom, of a shape following the general oblong sha e of the insulator and extending around t ie said separate bottom supports in common. v
11. An oblong insulator having a conductor su thidirection of the greatest length of the port extending `along the insulator in latter, and separate supporting members for said insulator, the supporting members being spaced in the direction of the length of the insulator.
12. An insulator gaging the element to be and receiving the strain of the supported element, the said insulator having separate supporting members spaced apart in t irection of the strain on the insulator.
13. An insulator having commodating dead-end cab opposite directions, said insulator having supporting pins spaced from each other in the line of strain and located respectively adjacent to the points of contact of the respective cables.
14. An insulator having .i supporting porsaid portion being elongated in the direction of the length of the conductor, and separatepins supporting the insulator, said pins Ibeing located in line with eachother in the direction of the length of theconductor and being located adhaving a portion forenyjacent the ends of the said supporting portion for the conductor. y 15. As an article of manufacture, an insulator having a portion for receiving a conductor, and having a plurality of supporting pins spaced from 'each other and arranged in the line of and perpendicular to the direction of the conductor.
-16. As an article of manufacture, an insulator havin surfaces at o' osite points against whic deadeended ca lies may bear, and a plurality of vertical supporting pins, said pins being located one adjacent to each ofsaid bearing points for cables.
17. As an article of manufacture, an ,insu-v a-plurality of vertical supportinement with each other and lator having ing pins in. a
spaced apart in the direction of the line vof strain.
18. An insulator comprising a body por? tion provided with means for sustaining a conductor, anda plurality of pins supporting said body portion and disposed substantially in alinement relatively to vsaid conductor.
supported thereon ortions for aces Yextending in 151). As an article of portion of insulating material a roove for a conclue vi ed With a plurality in a plane parallel wit manufacture, a bod rovided Witli tor, an further `proof apertures disposed h sald groove for the purpose of receiving supporting pins;
In testimony whereo I have signed my WALTON HARRISON, EVERARD MARSHALL.v
US29799106A 1906-01-26 1906-01-26 Insulator for heavy currents. Expired - Lifetime US885678A (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3324659A (en) * 1965-09-07 1967-06-13 David C Byers Electrostatic thrustor with improved insulators
US3329767A (en) * 1965-07-22 1967-07-04 Lindsey Insulator mounting bracket

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3329767A (en) * 1965-07-22 1967-07-04 Lindsey Insulator mounting bracket
US3324659A (en) * 1965-09-07 1967-06-13 David C Byers Electrostatic thrustor with improved insulators

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