TILTABLE CORONA RING ASSEMBLY
United States Patent 3775553
A split, generally elliptically-shaped corona ring has a bearing member secured at each end thereof to permit rotational movement of the ring relative to a transmission line yoke plate. Bolts are received in respective elongated openings in the bearing members and their heads engage flat surfaces thereon, when the bolts are threaded into the yoke plate, to hold the ring in selected angular positions relative to the yoke plate. Stop surfaces on the bearing members engage the yoke plate for limiting rotary movement of the ring relative to the yoke plate.
Inventors:
Corley, William P. (Birmingham, AL)
Glass, James D. (Birmingham, AL)
Glass, James D. (Birmingham, AL)
Application Number:
05/331401
Publication Date:
11/27/1973
Filing Date:
02/12/1973
View Patent Images:
Export Citation:
Assignee:
Anderson Electric Corporation (Leeds, AL)
Primary Class:
Other Classes:
174/141R
International Classes:
H01B17/44; H02G7/20; H01B17/42; H01B17/44; H01T19/02
Field of Search:
174/14CR,141R,141C,144
Primary Examiner:
Askin, Laramie E.
Claims:
We claim
1. A tiltable corona ring assembly comprising a split metal ring having opposite end portions spaced apart from each other, a pair of bearing members having inner and outer surfaces and secured respectively to the end portions of the ring and aligned along a common axis, the bearing members each having an opening therein extending radially of the axis from said outer surface to said inner surface and elongated in a circumferential direction with respect to said axis, and retaining members passing through the respective openings for securing the assembly to a supporting surface at selected angular positions relative to the supporting surface and about said axis.
2. A tiltable corona ring assembly as claimed in claim 1 wherein each opening has a central portion of reduced circumferential length with respect to said axis.
3. A tiltable corona ring assembly as claimed in claim 2 wherein the end walls of the central portion of each opening are defined by a pair of curved surfaces which are convex with respect to each other.
4. A tiltable corona ring assembly as claimed in claim 1 wherein the split metal ring is generally elliptical.
5. A tiltable corona ring assembly as claimed in claim 4 wherein the split metal ring is tubular in cross section.
6. A tiltable corona ring assembly as claimed in claim 1 wherein each retaining member has a shaft portion and an enlarged head portion for engaging the outer surface of its associated bearing member about the opening therein.
7. A tiltable corona ring assembly as claimed in claim 1 wherein each inner surface has a curved portion intermediate a pair of substantially flat stop surfaces, each said curved surface portion extending circumferentially of said axis and said stop surfaces of each pair being disposed at an angle with respect to each other.
8. A tiltable corona ring as claimed in claim 7 wherein said angle is substantially 90°.
9. A tiltable corona ring assembly as claimed in claim 7 wherein each outer surface has a curved surface portion extending circumferentially of said axis.
10. A tiltable corona ring assembly comprising a generally elliptical split metal ring having a tubular cross section and having opposite end portions spaced apart from each other, a pair of bearing members secured respectively to the end portions of the ring and aligned along a common axis and having inner and outer surfaces, each said inner surface having a curved portion intermediate a pair of substantially flat stop surfaces, each said curved surface extending circumferentially of said axis and each pair of said stop surfaces being disposed at an acute angle with respect to each other, each pair of said outer surfaces having a curved portion extending circumferentially of said axis, each bearing member having an opening therein extending radially of the axis from said outer surface to said inner surface and elongated in a circumferential direction with respect to said axis, each opening having a central portion of reduced circumferential length and defined by a pair of curved end walls which are convex with respect to each other, and retaining members having a shaft portion passing through the respective openings for securing the assembly to a supporting surface at selected angular positions relative to the supporting surface and about said axis, each retaining member having an enlarged head portion for engaging the outer surface of its associated bearing member about the opening therein.
1. A tiltable corona ring assembly comprising a split metal ring having opposite end portions spaced apart from each other, a pair of bearing members having inner and outer surfaces and secured respectively to the end portions of the ring and aligned along a common axis, the bearing members each having an opening therein extending radially of the axis from said outer surface to said inner surface and elongated in a circumferential direction with respect to said axis, and retaining members passing through the respective openings for securing the assembly to a supporting surface at selected angular positions relative to the supporting surface and about said axis.
2. A tiltable corona ring assembly as claimed in claim 1 wherein each opening has a central portion of reduced circumferential length with respect to said axis.
3. A tiltable corona ring assembly as claimed in claim 2 wherein the end walls of the central portion of each opening are defined by a pair of curved surfaces which are convex with respect to each other.
4. A tiltable corona ring assembly as claimed in claim 1 wherein the split metal ring is generally elliptical.
5. A tiltable corona ring assembly as claimed in claim 4 wherein the split metal ring is tubular in cross section.
6. A tiltable corona ring assembly as claimed in claim 1 wherein each retaining member has a shaft portion and an enlarged head portion for engaging the outer surface of its associated bearing member about the opening therein.
7. A tiltable corona ring assembly as claimed in claim 1 wherein each inner surface has a curved portion intermediate a pair of substantially flat stop surfaces, each said curved surface portion extending circumferentially of said axis and said stop surfaces of each pair being disposed at an angle with respect to each other.
8. A tiltable corona ring as claimed in claim 7 wherein said angle is substantially 90°.
9. A tiltable corona ring assembly as claimed in claim 7 wherein each outer surface has a curved surface portion extending circumferentially of said axis.
10. A tiltable corona ring assembly comprising a generally elliptical split metal ring having a tubular cross section and having opposite end portions spaced apart from each other, a pair of bearing members secured respectively to the end portions of the ring and aligned along a common axis and having inner and outer surfaces, each said inner surface having a curved portion intermediate a pair of substantially flat stop surfaces, each said curved surface extending circumferentially of said axis and each pair of said stop surfaces being disposed at an acute angle with respect to each other, each pair of said outer surfaces having a curved portion extending circumferentially of said axis, each bearing member having an opening therein extending radially of the axis from said outer surface to said inner surface and elongated in a circumferential direction with respect to said axis, each opening having a central portion of reduced circumferential length and defined by a pair of curved end walls which are convex with respect to each other, and retaining members having a shaft portion passing through the respective openings for securing the assembly to a supporting surface at selected angular positions relative to the supporting surface and about said axis, each retaining member having an enlarged head portion for engaging the outer surface of its associated bearing member about the opening therein.
Description:
BACKGROUND OF THE INVENTION
A major problem in transmission line maintenance is the positioning of corona rings or shields while working on insulator strings. Since it is the usual practice to provide continuous service, this work is often performed while the electrical lines are energized. Heretofore, as to corona ring assemblies that are attachable to the standard yoke plates of insulator strings by bolts, complete removal of the corona ring assembly is required before working on the insulator string. Slotted mounting brackets are sometimes provided thereby to eliminate the necessity of removing the mounting bolts entirely, but heretofore such corona ring assemblies have had to be removed to provide access to the insulators by the line tools. Complete removal and replacement of the corona ring assembly is not only troublesome and costly; it is extremely hazardous.
SUMMARY OF THE INVENTION
The improved corona ring assembly may be carried by a yoke plate connecting an insulator string to a conductor, and is mounted to permit restricted rotary movement of the corona ring relative to the yoke plate or other support. The assembly comprises a generally elliptically-shaped shield element or ring formed of metal tubing and a pair of bearing members each having a pair of stop surfaces which engage the yoke plate upon a predetermined amount of rotation of the assembly relative to the yoke plate. Releaseable retaining bolts of the assembly are captively mounted to the yoke plate and serve to secure the assembly thereto with the corona ring at selected angular positions relative to the yoke plate. During maintenance, it is only necessary to loosen the retaining bolts and then tilt the corona ring out of the way. When maintenance is completed, the ring is moved back to its original position whereupon two of the stop surfaces engage the yoke plate and properly align the corona ring. The retaining members are then tightened thereby securing the assembly in place.
It is an object of the invention to provide an improved tilt-away corona ring assembly which is durable, comprises few and simple parts, is easy to install, and is captively mountable on a yoke plate.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects and advantages of the invention will become apparent from the following description wherein reference is made to the drawings, in which:
FIG. 1 is an elevational view showing a corona shield or ring assembly in accordance with this invention mounted on a yoke plate forming part of a double insulator string;
FIG. 2 is an enlarged side elevational view of the structure shown in FIG. 1; and
FIG. 3 is an enlarged sectional view taken generally along the line 3--3 of FIG. 1.
DETAILED DESCRIPTION OF THE INVENTION
Referring to the drawings, a corona shield or ring assembly 10 is shown as carried by a yoke plate 12 of a double insulator string and having two pairs of eye portions 14 and 16. The eye portions 14 are pivotally connected by respective pins 18 to respective end portions 20 of a pair of links 22. The other end portions of the links 22 are connected to respective adjacent ends of respective insulator string assemblies 25. Strain clamp clevises 26 are attached by respective pins 18 to the respective eye members 16.
The corona ring assembly 10 comprises a pair of bearing members 28, aligned along a common axis and connected as by welding to respective opposite ends of a generally elliptically-shaped metal corona ring 30 preferably formed of metal tubing. Each bearing member 28 has an opening 31, an inner surface 32 having a curved portion 34 intermediate a pair of stop surfaces 35a and 35b, which stop surfaces are preferably disposed at an angle of approximately 90° with respect to each other, and an outer surface 36 shaped generally like the inner surface 32. Each opening 31 has inner and outer end portions 31a and 31b, respectively, and a central portion 31c, and extends radially of the common axis of the bearing members 28 from the outer surface 36 to the inner surface 32. The opening 31 is elongated in a direction circumferential of the common axis. The central portion 31c of the opening 31 is of reduced circumferential length and is defined by a pair of curved surfaces which are convex with respect to each other. The assembly 10 also includes two retaining members, such as a bolt 38. Each bolt 38 has a flange 38a adjacent a head portion, extends through one of the openings 31 and is threaded into an associated hole 33 in the yoke plate 12 and captively secured as by a cotter pin 40.
Although the drawings show the invention as applied to a double dead end insulator string, it is obvious that the invention may also be applied to a single dead end insulator string, and similar structures.
From the aforegoing description, the mounting of the assembly 10 may be readily understood. The bearing members 28 are positioned so that the openings 31 are aligned respectively with the threaded holes 33. The retaining bolts 38 are inserted into the respective openings 31 and are threaded into the respective holes 33. The corona ring 30 is then rotated to the solid line position shown in the drawings wherein the stop surfaces 35a of the bearing members 28 are in engagement with a surface 42 of the yoke plate 12. With the ring 30 thus properly located in its operative position, the retaining bolts 38 are tightened so that the flanges 38a of the bolts 38 engage the respective outer surfaces 36 to secure the ring assembly 10 fixedly in its operative position shown in solid lines.
Prior to line maintenance work, the retaining bolts 38 are loosened thereby permitting the bearing members 28 to turn relative to the bolts 38 and the yoke plate 12. The corona ring 30 is then rotated to the inoperative position shown in broken lines. In this position, the ring 30 is out of the way while the line is repaired. After maintenance is completed, the ring 30 is tilted back to the operative position shown in solid lines, and the bolts 38 are retightened.
The corona ring 30 may also be positioned and secured intermediate the broken line and solid positions shown in the drawings. An intermediate position may be desirable from a maintenance or electrical standpoint.
Thus it is apparent that there has been provided, in accordance with the invention, a tilt-away corona ring or shield assembly that fully satisfies the objects, aims, and advantages set forth above. While the invention has been described in conjunction with a specific embodiment, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art in light of the aforegoing description. Accordingly, it is intended to embrace all such alternatives, modifications and variations as fall within the spirit and scope of the appended claims.
A major problem in transmission line maintenance is the positioning of corona rings or shields while working on insulator strings. Since it is the usual practice to provide continuous service, this work is often performed while the electrical lines are energized. Heretofore, as to corona ring assemblies that are attachable to the standard yoke plates of insulator strings by bolts, complete removal of the corona ring assembly is required before working on the insulator string. Slotted mounting brackets are sometimes provided thereby to eliminate the necessity of removing the mounting bolts entirely, but heretofore such corona ring assemblies have had to be removed to provide access to the insulators by the line tools. Complete removal and replacement of the corona ring assembly is not only troublesome and costly; it is extremely hazardous.
SUMMARY OF THE INVENTION
The improved corona ring assembly may be carried by a yoke plate connecting an insulator string to a conductor, and is mounted to permit restricted rotary movement of the corona ring relative to the yoke plate or other support. The assembly comprises a generally elliptically-shaped shield element or ring formed of metal tubing and a pair of bearing members each having a pair of stop surfaces which engage the yoke plate upon a predetermined amount of rotation of the assembly relative to the yoke plate. Releaseable retaining bolts of the assembly are captively mounted to the yoke plate and serve to secure the assembly thereto with the corona ring at selected angular positions relative to the yoke plate. During maintenance, it is only necessary to loosen the retaining bolts and then tilt the corona ring out of the way. When maintenance is completed, the ring is moved back to its original position whereupon two of the stop surfaces engage the yoke plate and properly align the corona ring. The retaining members are then tightened thereby securing the assembly in place.
It is an object of the invention to provide an improved tilt-away corona ring assembly which is durable, comprises few and simple parts, is easy to install, and is captively mountable on a yoke plate.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects and advantages of the invention will become apparent from the following description wherein reference is made to the drawings, in which:
FIG. 1 is an elevational view showing a corona shield or ring assembly in accordance with this invention mounted on a yoke plate forming part of a double insulator string;
FIG. 2 is an enlarged side elevational view of the structure shown in FIG. 1; and
FIG. 3 is an enlarged sectional view taken generally along the line 3--3 of FIG. 1.
DETAILED DESCRIPTION OF THE INVENTION
Referring to the drawings, a corona shield or ring assembly 10 is shown as carried by a yoke plate 12 of a double insulator string and having two pairs of eye portions 14 and 16. The eye portions 14 are pivotally connected by respective pins 18 to respective end portions 20 of a pair of links 22. The other end portions of the links 22 are connected to respective adjacent ends of respective insulator string assemblies 25. Strain clamp clevises 26 are attached by respective pins 18 to the respective eye members 16.
The corona ring assembly 10 comprises a pair of bearing members 28, aligned along a common axis and connected as by welding to respective opposite ends of a generally elliptically-shaped metal corona ring 30 preferably formed of metal tubing. Each bearing member 28 has an opening 31, an inner surface 32 having a curved portion 34 intermediate a pair of stop surfaces 35a and 35b, which stop surfaces are preferably disposed at an angle of approximately 90° with respect to each other, and an outer surface 36 shaped generally like the inner surface 32. Each opening 31 has inner and outer end portions 31a and 31b, respectively, and a central portion 31c, and extends radially of the common axis of the bearing members 28 from the outer surface 36 to the inner surface 32. The opening 31 is elongated in a direction circumferential of the common axis. The central portion 31c of the opening 31 is of reduced circumferential length and is defined by a pair of curved surfaces which are convex with respect to each other. The assembly 10 also includes two retaining members, such as a bolt 38. Each bolt 38 has a flange 38a adjacent a head portion, extends through one of the openings 31 and is threaded into an associated hole 33 in the yoke plate 12 and captively secured as by a cotter pin 40.
Although the drawings show the invention as applied to a double dead end insulator string, it is obvious that the invention may also be applied to a single dead end insulator string, and similar structures.
From the aforegoing description, the mounting of the assembly 10 may be readily understood. The bearing members 28 are positioned so that the openings 31 are aligned respectively with the threaded holes 33. The retaining bolts 38 are inserted into the respective openings 31 and are threaded into the respective holes 33. The corona ring 30 is then rotated to the solid line position shown in the drawings wherein the stop surfaces 35a of the bearing members 28 are in engagement with a surface 42 of the yoke plate 12. With the ring 30 thus properly located in its operative position, the retaining bolts 38 are tightened so that the flanges 38a of the bolts 38 engage the respective outer surfaces 36 to secure the ring assembly 10 fixedly in its operative position shown in solid lines.
Prior to line maintenance work, the retaining bolts 38 are loosened thereby permitting the bearing members 28 to turn relative to the bolts 38 and the yoke plate 12. The corona ring 30 is then rotated to the inoperative position shown in broken lines. In this position, the ring 30 is out of the way while the line is repaired. After maintenance is completed, the ring 30 is tilted back to the operative position shown in solid lines, and the bolts 38 are retightened.
The corona ring 30 may also be positioned and secured intermediate the broken line and solid positions shown in the drawings. An intermediate position may be desirable from a maintenance or electrical standpoint.
Thus it is apparent that there has been provided, in accordance with the invention, a tilt-away corona ring or shield assembly that fully satisfies the objects, aims, and advantages set forth above. While the invention has been described in conjunction with a specific embodiment, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art in light of the aforegoing description. Accordingly, it is intended to embrace all such alternatives, modifications and variations as fall within the spirit and scope of the appended claims.