Base assembly for an insulator assembly

Information

  • Patent Grant
  • 6525274
  • Patent Number
    6,525,274
  • Date Filed
    Tuesday, September 25, 2001
    23 years ago
  • Date Issued
    Tuesday, February 25, 2003
    21 years ago
Abstract
An insulator assembly has a base assembly that is rigidly connected and is not prone to movement over time. A first support member has first and second ends with first and second pluralities of holes for receiving a first switch assembly. A second support member has first and second ends with third and fourth pluralities of holes for receiving a second switch assembly. A third support member has first and second ends. The first end of the third support member is attached to the first support member and the second end of the third support member is attached to the second support member. The third support member has a fifth plurality of holes for attaching the base assembly to a support.
Description




FIELD OF THE INVENTION




The present invention relates to an insulator assembly. More particularly, the present invention relates to an insulator assembly having a base assembly that is rigidly connected and is not prone to movement over time.




BACKGROUND OF THE INVENTION




Distribution reclosers are mounted to support structures in electrical power distribution systems to prevent longer than momentary disruptions of electrical service, such as might be caused by a short circuit, and to provide continuous electric service. For example, wind conditions often cause power lines strung between poles to swing, thereby momentarily touching each other or a grounded conductor. Additionally, objects may fall across exposed wires, arcing could occur, or other transitory events could cause momentary power line short circuits or current surges that could burn out a fuse or trip a circuit breaker. Most of these faults are self correcting and do not require permanent fuse or circuit breaker protection because they terminate quickly. Reclosers sense and interrupt fault currents and automatically restore service after momentary outages after the temporary fault condition is gone. If a fault is permanent, the recloser locks open after a preset number of operations and isolates the faulted section of the system from the main system.




Bypass switch assemblies may be used to provide an economical and practical method of bypassing current and disconnecting distribution reclosers to provide maintenance to the reclosers without interrupting electrical service. Once the recloser has been isolated from the electrical distribution system, maintenance may be performed on the recloser without impairing continuous electric power.




Insulator assemblies are spaced from the support structures to which they are attached, such as utility poles. The sizes of switches and conductors are based upon the current and basic insulation level requirements. The stiffness of a conductor increases as the diameter of the conductor increases. Stiffer conductors are less flexible, thereby preventing them from being easily formed to facilitate connecting with connectors on terminal pads and maintaining electrical clearance to grounded parts. Terminal pads for existing switch assemblies are flat, thereby requiring some forming of conductors to connect to bypass switch assemblies that are mounted near the support structure. Due to the stiffness of large conductors, difficulty exists in forming to the degree necessary to connect to the straight terminal pads of existing insulator assemblies that are mounted near the support structures. Therefore, it is difficult to connect large conductors to terminal pads of existing insulator assemblies that are mounted close to support structures due to the inflexibility of the conductor. A need exists for a terminal pad that allows conductors to be connected to insulator assemblies that are mounted near support structures.




Insulator assemblies are mounted to support structures using multi-piece mounting assemblies. Such multi-piece mounting assemblies are unwieldy as they require a technician to carry a number of different parts in the field. Moreover, installation is difficult and slow due to the number of parts that must be assembled. Therefore, a need exists for a mounting assembly for an insulator assembly that has few parts and is quick and easy to install.




Insulator assemblies are supported on base assemblies that are bolted together, which allow movement of the parts of the base assemblies over time. Such movement is due to many uncontrollable events, such as weather, animals, vandalism and the operation of the switches mounted on the base assemblies. Movement of the base assemblies causes the blade and contact of the insulator assemblies to move out of alignment, thereby effecting electricity transfer through the insulator assembly. Therefore, a need exists for a base assembly for an insulator assembly that is rigidly connected and is not prone to movement over time.




Elaborate shunting devices are needed to transfer electricity from the terminal pads to the contacts of switch assemblies of insulator assemblies when the bypass blades of bypass switch assemblies are in open positions, which is the normal operating position for bypass switch assemblies. The shunting devices are bulky and difficult to install. Therefore, a need exists for a bypass switch assembly that transfers electrical current from the terminal pad of a bypass switch assembly to the contact of a switch assembly of an insulator assembly without a shunting device.




Therefore, a need exists for improved insulator assemblies.




SUMMARY OF THE INVENTION




Accordingly, it is an objective of the present invention to provide an insulator assembly having a base assembly that is rigidly connected, thereby preventing movement of parts of the mounting bracket and eliminating misalignment of the elements of the insulator assembly over time.




The foregoing objective is basically attained by providing a base assembly for an interrupter assembly. A first support member has first and second ends with first and second pluralities of holes for receiving a first switch assembly. A second support member has first and second ends with third and fourth pluralities of holes for receiving a second switch assembly. A third support member has first and second ends. The first end of the third support member is attached to the first support member and the second end of the third support member is attached to the second support member. The third support member has a fifth plurality of holes for attaching the base assembly to a support. The first, second and third support members of the base assembly are rigidly connected, thereby substantially eliminating movement of the support members over time. Therefore, since the base assembly is not prone to movement over time, the blades and contacts of the insulator assemblies are substantially prevented from moving, thereby avoiding misalignment between the blades and contacts.




Other objects, advantages and salient features of the invention will become apparent from the following detailed description, which, taken in conjunction with the annexed drawings, discloses a preferred embodiment of the invention.











BRIEF DESCRIPTION OF THE DRAWINGS




Referring now to the drawings that form a part of the original disclosure:





FIG. 1

is a side elevational view of an insulator assembly according to the present invention mounted to a support and receiving a conductor;





FIG. 2

is a side elevational view of the insulator assembly of

FIG. 1

with a bypass switch assembly;





FIG. 3

is a side elevational view of the switch assembly of

FIG. 2

without the mounting bracket;





FIG. 4

is a top plan view of the insulator assembly of

FIG. 2

;





FIG. 5

is a top plan view of a terminal pad of the insulator assembly of

FIG. 1

;





FIG. 6

is a top plan view of a base assembly of the insulator assembly of

FIG. 1

;





FIG. 7

is a front elevational view of the base assembly of

FIG. 6

, showing insulators mounted to the base;





FIG. 8

is front elevational view of a mounting bracket of the insulator assembly of

FIG. 1

;





FIG. 9

is a top plan view of the mounting bracket of

FIG. 8

, showing the mounting bracket secured to a support;





FIG. 10

is a side elevational view of the bypass switch assembly of

FIG. 2

, showing the bypass blade in a closed position;





FIG. 11

is a top plan view of the bypass switch assembly of

FIG. 10

;





FIG. 12

is a partial side elevational view in cross section of a spacer of the bypass switch assembly of

FIG. 10

;





FIG. 13

is a side elevational view of the spacer of the bypass switch assembly of

FIG. 10

, in which the bypass blade is in an open position;





FIG. 14

is a circuit diagram of the bypass switch assembly, the switch assembly and the recloser assembly of the present invention, showing the bypass assembly in an open position and the switch assemblies in a closed position; and





FIG. 15

is the circuit diagram of

FIG. 14

, showing the bypass assembly in a closed position and the switch assemblies in an open position.











DETAILED DESCRIPTION OF THE INVENTION




As shown in

FIGS. 1-15

, the present invention relates to an insulator assembly


11


for a recloser assembly


13


. The insulator assembly


11


includes two switch assemblies


15


and


17


and a bypass switch assembly


19


, as shown in FIG.


4


. The insulator assembly


11


provides economical and simple electrical bypassing and electrical disconnecting of the recloser assembly from the electrical distribution system. Switch assemblies


15


and


17


and bypass switch assembly


19


are mounted on a base assembly


31


. A mounting bracket


41


connected to the base assembly


31


secures the insulator assembly to a support


21


, such as a utility pole.




The first switch assembly


15


, as shown in

FIGS. 1-4

, has first and second insulators


51


and


53


, respectively. First insulator


51


has first and second end fittings


55


and


57


, respectively, attached at opposite ends of the first insulator. Second insulator


53


also has first and second end fittings


59


and


61


attached at opposite ends of the second insulator. The first end fittings


55


and


59


of insulators


51


and


53


receive fasteners for mounting each insulator to a base assembly


31


. A first end


63


of a first switch blade


64


is pivotally connected to the second end fitting


57


of the first insulator


51


. A second end


65


of the first switch blade


64


is engaged with a first contact


67


that is connected to the second end fitting


61


of the second insulator


53


. A first hook


69


connected to the second end fitting


61


guides the first switch blade


64


into electrical contact with the first contact


67


during closing of the first switch assembly


15


.




The second switch assembly


17


, as shown in

FIG. 4

, is assembled similarly to the first switch assembly


15


. The second switch assembly


17


has first and second insulators


71


and


73


, respectively. First insulator


71


has first and second end fittings, similar to end fittings


55


and


57


attached at opposite ends of the first insulator. Second insulator


73


also has first and second end fittings, similar to end fittings


59


and


61


attached at opposite ends of the second insulator. The first end fittings of insulators


71


and


73


receive fasteners for mounting each insulator to a base assembly


31


. A first end


83


of a second switch blade


84


is pivotally connected to the second end fitting of the first insulator


71


. A second end


85


of the second switch blade


84


is engaged with a second contact


87


that is connected to the second end fitting of the second insulator


73


. A second hook


89


connected to the second end fitting guides the second switch blade


84


into electrical contact with the second contact


87


during closing of the second switch assembly


17


.




As shown in

FIGS. 1-4

, first terminal pad


91


is connected between the second end fitting


57


of the first insulator


51


of the first switch assembly


15


and the first end


63


of the first switch blade


64


. As shown in

FIG. 4

, second terminal pad


93


is connected between the second end fitting of the first insulator


71


of the second switch assembly


17


and the first end


83


of the second switch blade


79


.




As shown in

FIGS. 1-5

, the first terminal pad


91


has a base


95


having angularly oriented first and second portions


97


and


99


, respectively. Preferably, the first and second portions


97


and


99


are integrally connected. Preferably, the angle


98


(

FIG. 2

) between first and second portions


97


and


99


is less than


180


degrees. More preferably, angle


98


is approximately 120 degrees. A first opening


101


in the first portion


97


facilitates connecting the first terminal pad


91


to the second end fitting


57


of the first insulator


51


of the first switch assembly


15


. A second opening


103


in the second portion


99


receives a fastener to facilitate connecting a connector


105


(

FIG. 1

) to the first terminal pad


91


. Preferably, as shown in

FIG. 5

, there are two first openings


101


and two second openings


103


. Second terminal pad


93


is constructed similarly to first terminal pad


91


.




Base assembly


31


, shown in

FIGS. 6-7

, has a first, second and third support members


32


,


33


and


34


, respectively. Preferably, each of the support members is substantially U-shaped, as shown in

FIG. 7. A

first end


35


of third support member


34


is attached to first support member


32


. A second end


36


of third support member


34


is attached to second support member


32


. Preferably, third support member


34


is welded to first and second support members


32


and


33


, respectively, thereby providing a rigid base assembly


31


. Preferably, as shown in

FIG. 6

, first and second support members


32


and


33


are substantially parallel and third support member


34


is substantially perpendicular to both first and second support members.




First support member


32


has first and second pluralities of holes


37


and


38


, respectively, for receiving first and second insulators


71


and


73


of the second switch assembly


17


. Second support member


33


has second and third pluralities of holes


39


and


40


for receiving first and second insulators


51


and


53


of first insulator assembly


15


. Each of the first, second, third and fourth pluralities of holes


37


,


38


,


39


and


40


are adapted to receive a variety of insulator configurations, thereby providing versatility to the base assembly. Third support member has a fifth plurality of holes


30


for connecting to a support structure or to the mounting bracket


41


.




Mounting bracket


41


, as shown in FIGS.


1


and


7


-


8


, has a base


42


having first and second ends


43


and


44


, respectively. A first leg


45


has a first end


46


attached to the first end


43


of the base


42


. Preferably, angle


115


between first leg


45


and base


42


is approximately 30 degrees. A second leg


47


has a first end


48


attached to the second end


44


of the base


42


. Preferably, angle


117


between second leg


47


and base


42


is approximately 150 degrees. Preferably, first leg


45


and second leg


47


are substantially parallel. A first foot


111


extends from second end


49


of first leg


45


. A second foot extends


113


from second end


50


of second leg


47


. Preferably, first foot


111


and second foot


113


extend in opposite directions from first and second legs


45


and


47


, respectively. Preferably, base


42


, first leg


45


, first foot


111


, second leg


47


and second foot


113


are integrally connected.




Fastener holes


119


and


121


in first and second feet


111


and


113


, respectively, receive fasteners


123


and


125


to secure mounting bracket


41


to a support


21


, such as a utility pole. Fastener hole


127


in base


41


receives fastener


129


to secure mounting bracket


41


to base assembly


31


.




Corners


131


,


133


,


135


and


137


of first and second feet


111


and


113


of mounting bracket


41


are bent toward support structure


21


to provide a more secure attachment to the support structure. Bent corners


131


,


133


,


135


and


137


dig into support structure as


123


and


125


are tightened, thereby providing additional stability to the insulator assembly


11


during the lifetime of the insulator assembly


11


.




The bypass switch assembly


19


, as shown in

FIGS. 1

,


4


and


10


-


11


, allows for quick and easy bypassing and disconnecting of the recloser assembly


13


from the electrical distribution system. The bypass switch assembly


19


is shown in a closed position in

FIG. 4

; an open position is shown with phantom lines. The bypass switch assembly


19


has first and second terminal pads


141


and


143


, respectively, for receiving and transferring electrical current. Connectors (not shown) may be attached to terminal pads


141


and


143


to receive electrical conductors. A bypass blade


145


transfers electrical current from first terminal pad


141


to second terminal pad


143


when in a closed position, as shown in FIG.


4


. In normal operation, bypass blade


145


is in an open position, as shown in phantom lines in

FIG. 4

, and first and second switch blades


64


and


84


are in a closed position to transfer electrical current to and from the recloser assembly. Closing bypass blade


145


and opening first and second switch blades


64


and


84


electrically isolates the recloser assembly from the electrical distribution system by transferring the electrical current from the first terminal pad


141


to the second terminal pad


143


, thereby bypassing the first and second switch assemblies


15


and


17


.




When the bypass switch assembly is in the open position, a spacer


151


, as shown in

FIGS. 10-14

, transmits electrical current from the first terminal pad


141


to a contact (first latch)


67


of the first switch blade


64


of the first switch assembly


15


. When the bypass blade


145


is closed, the spacer


151


serves no function since electrical current is not transferred to the first switch blade


64


since it is in an open position.




Spacer


151


is disposed in opening


152


in steel support member


153


. The steel support member provides the same function as that of the first hook


69


of the first switch assembly


15


, i.e., facilitates closing of the bypass blade


145


and connecting with contact end


142


of first terminal pad


141


. Preferably, spacer


151


is thicker than the steel support member


153


, thereby providing a good electrical contact between the first terminal pad


141


of the bypass assembly


19


and the contact (first latch)


67


of the first switch assembly


15


. Fastener


161


secures bypass switch assembly terminal pad


141


, steel support member


153


, and first latch


67


and first hook of first switch assembly


15


together.




ASSEMBLY, DISASSEMBLY AND OPERATION




An insulator assembly


11


according to the present invention is shown fully assembled in FIG.


2


. The insulator assembly


11


has a base assembly


31


to which first and second switch assemblies


15


and


17


are mounted. A bypass assembly


19


may then be added by attaching a first end of the bypass switch assembly to the first switch assembly and attaching a second end of the bypass switch assembly to the second switch assembly, as shown in FIG.


4


.




As shown in

FIG. 2

, the base assembly


31


is then secured by fasteners


129


to the mounting bracket


41


. The base assembly


31


may be directly secured to a support structure without mounting bracket


41


. The mounting bracket


41


is then secured using fasteners


123


and


125


to a support structure


21


, as shown in FIG.


1


. For reasons of clarity, the bypass switch assembly is not shown in FIG.


1


. As fasteners


123


and


125


are tightened, bent corners


131


,


133


,


135


and


137


are drawn into support structure


21


, thereby providing a secure attachment to the support structure.




Electrical conductors


171


from the recloser assembly


13


are then connected to connectors


105


attached to first and second terminal pads of first and second switch assemblies


15


and


17


, respectively, as shown in FIG.


1


. Electrical conductors (not shown) to and from the insulator assembly


11


are connected to first and second terminal pads


141


and


143


of the bypass switch assembly.




Electrical circuit diagrams of the insulator assembly


11


and the recloser assembly


13


are shown in

FIGS. 14 and 15

. The normal operating mode is shown in FIG.


15


. Electrical current is received at the first terminal pad


141


of bypass switch assembly


19


(FIG.


4


). Since bypass switch assembly


19


is in the open position, the electrical current is prevented from traveling through the bypass switch assembly. The electrical current is transferred through the first switch assembly


15


, through the recloser assembly


13


and through the second switch assembly


17


. The electrical current is transferred to the second terminal pad


143


of the bypass switch assembly


19


and is then transferred from the insulator assembly


11


.




The bypass mode of the insulator assembly


11


is shown in FIG.


14


. Both the first and second switch assemblies


15


and


17


are in the open position and the bypass switch assembly


19


is in the closed position. Since the first switch assembly


15


is open, electrical current travels through the bypass switch assembly


19


and is then transferred from the insulator assembly


11


, thereby bypassing the recloser assembly


13


. The bypass mode electrically isolates the recloser assembly from the electrical distribution system so work may be performed on the recloser assembly.




While advantageous embodiments have been chosen to illustrate the invention, it will be understood by those skilled in the art that various changes and modifications may be made therein without departing from the scope of the invention as defined in the appended claims.



Claims
  • 1. A base assembly for an insulator assembly, comprising:a first continuous support member having first and second ends with first and second pluralities of holes for receiving the entirety of a first switch assembly; a second continuous support member having first and second ends with third and fourth pluralities of holes for receiving the entirety of a second switch assembly; and a third continuous support member having first and second ends, said first end of said third support member being attached to said first support member and said second end of said third support member being attached to said second support member, said third support member having a fifth plurality of holes for attaching said base assembly to a support.
  • 2. A base assembly according to claim 1, whereineach of said first, second and third support members is substantially U-shaped.
  • 3. A base assembly according to claim 1, whereinsaid first and second support members are substantially parallel.
  • 4. A base assembly according to claim 1, whereinsaid third support member is substantially perpendicular to said first and second support members.
  • 5. A base assembly according to claim 1, whereinsaid third support member is welded to each of said first and second support members.
  • 6. A base assembly according to claim 1, wherein:each of said first and third plurality of holes has eight holes and each of said second and fourth plurality of holes has four holes, said first, second, third and fourth plurality of holes being configured to receive a variety of switch assemblies.
  • 7. A base assembly for an insulator assembly, comprising:a substantially U-shaped continuous first support member having first and second ends with first and second pluralities of holes for receiving the entirety of a first switch assembly; a substantially U-shaped continuous second support member being substantially parallel to said first support member and having first and second ends with third and fourth pluralities of holes for receiving the entirety of a second switch assembly; and a continuous third support member having first and second ends, said first end of said third support member being attached to said first support member, said second end of said third support member being attached to said second support member, said third support member being substantially perpendicular to said first and second support members, and having a fifth plurality of holes for attaching said base assembly to a support.
  • 8. A base assembly according to claim 7, wherein:said third support member is welded to each of said first and second support members.
  • 9. A base assembly according to claim 7, wherein:each of said first and third plurality of holes has eight holes and each of said second and fourth plurality of holes has four holes, said first, second, third and fourth plurality of holes being configured to receive a variety of first and second switch assemblies.
  • 10. An insulator assembly, comprising:first and second switch assemblies; a base assembly, said base assembly including a substantially U-shaped first support member having first and second ends with first and second pluralities of holes for receiving the entirety of said first switch assembly; a substantially U-shaped second support member being substantially parallel to said first support member and having first and second ends with third and fourth pluralities of holes for receiving the entirety of said second switch assembly; and a third support member having first and second ends, said first end of said third support member being attached to said first support member, said second end of said third support member being attached to said second support member, said third support member being substantially perpendicular to said first and second support members, and having a fifth plurality of holes for attaching said base assembly to a support; first and second terminal pads having first ends attached to said first and second switch assemblies, respectively, and having second ends connected to conductors; and a support mounting bracket attached to said third support member.
  • 11. An insulator assembly according to claim 10, wherein:said third support member is welded to each of said first and second support members.
  • 12. An insulator assembly according to claim 10, wherein:each of said first and third plurality of holes has eight holes and each of said second and fourth plurality of holes has four holes, said first, second, third and fourth plurality of holes being configured to receive a variety of first and second switch assemblies.
  • 13. An insulator assembly, comprising:first and second switch assemblies; a base assembly, said base assembly including a substantially U-shaped first support member having first and second ends with first and second pluralities of holes for receiving said first switch assembly; a substantially U-shaped second support member being substantially parallel to said first support member and having first and second ends with third and fourth pluralities of holes for receiving said second switch assembly; and a third support member having first and second ends, said first end of said third support member being attached to said first support member, said second end of said third support member being attached to said second support member, said third support member being substantially perpendicular to said first and second support members, and having a fifth plurality of holes for attaching said base assembly to a support; first and second terminal pads having first ends attached to said first and second switch assemblies, respectively, and having second ends connected to conductors; a support mounting bracket attached to said third support member; and a bypass switch assembly connected to said first and second support members.
  • 14. An insulator assembly according to claim 13, whereinsaid bypass switch assembly has first and second ends, said first end of said bypass switch assembly being connected to said first support member and said second end of said bypass switch assembly being connected to said second support member.
  • 15. An insulator assembly according to claim 13, whereinsaid first switch assembly has first and second insulators, each of which is attached to said first support member.
  • 16. An insulator assembly according to claim 15, whereinsaid second switch assembly has third and fourth insulators, each of which is attached to said second support member.
REFERENCE TO RELATED APPLICATIONS

This application is related to U.S. patent application Ser. No. 09/961,402, entitled Terminal Pad for an Insulator Assembly; U.S. Ser. No. 09/961,333, entitled Mounting Bracket for an Insulator Assembly; and U.S. Ser. No. 09/961,346, entitled Spacer for an Insulator Assembly, all concurrently filed herewith in the name of Gerald B. Roberts, the subject matter of each of which is hereby incorporated by reference.

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