US3883709A

US3883709A - Vacuum capacitor switch having grounding switch means

Info

Publication number: US3883709A
Application number: US422893A
Authority: US
Inventors: David R Cole
Original assignee: Allis Chalmers Corp
Current assignee: Allis Chalmers Corp; Continental Eagle Corp
Priority date: 1973-12-07
Filing date: 1973-12-07
Publication date: 1975-05-13
Anticipated expiration: 1992-05-13

Abstract

A multiphase vacuum capacitor switch having a vacuum interrupter for each phase and including a grounding switch associated with each interrupter as an integral part of the main switch. The three phases of the ground switch operate simultaneously.

Description

United States Patent Cole [ VACUUM CAPACITOR SWITCH HAVING GROUNDING SWITCH MEANS [75] Inventor: David R. Cole, Tigard, Oreg.

[73] Assignee: Allis-Chalmers Corporation,

Milwaukee, Wis.

[22] Filed: Dec. 7, 1973 [2l] Appl. No.: 422,893

[52] US. Cl. 200/144 B; 200/145 R [51] Int. Cl. I'IOIh 33/66 [58] Field of Search 200/l44 B, 148 F. 145 R [56] Reterences Cited UNITED STATES PATENTS 2,554,974 5/l95l Beatty ZOO/I48 F [451 May 13, 1975 3,787,649 H1974 Goodwin. Jr. et a] ZOO/I44 B Primary ExaminerRobert S. Macon Anorney, Agent, or Firm-Robert C. Jones [57] ABSTRACT A multiphase vacuum capacitor switch having a vacuum interrupter for each phase and including a grounding switch associated with each interrupter as an integral part of the main switch. The three phases of the ground switch operate simultaneously.

3 Claims, 2 Drawing Figures VACUUM CAPACITOR SWITCH HAVING GROUNDING SWITCH MEANS BACKGROUND OF THE INVENTION This invention relates to electric switches. particularly to a vacuum type capacitor switch which is normally mounted on superstructure above ground level.

In installation of vacuum capacitor switches. it is the practice to provide two completely independent switch arrangements. Thus, the vacuum capacitor switches are constructed and arranged for operation in a manner that completely ignores grounding switch requirements. In this type of an arrangement, the grounding switches are separated structures completely indepen dent of and from the vacuum capacitor switch. This type ofconstruction is costly from the standpoint of requiring independent supporting structures such as independent insulators and superstructures. In addition to the independent structures, it is also necessary to provide interlocks which with independent structures can be complicated and costly.

SUMMARY OF THE INVENTION In accordance with the invention. a vacuum capacitor switch having a ground switch integral therewith is mounted on a supporting frame with the individual phase interrupters in side-by-side relationship. Each interrupter phase includes a pair of hollow upper and lower insulators which are disposed in axial alignment. The upper hollow insulator of each phase houses the vacuum interrupter. Common operating means for the interrupters are operatively carried within the supporting frame. A metallic terminal having a clearance opening for the interrupter operating rod is interposed between the lower and upper insulations of each phase. A metallic cap terminal is secured to the top axial end of each upper insulator and serves as a support for the depending stationary contact rod of the interrupter. Each of the metallic terminals also accommodates a ground switch contact which is supported in position to receive the end of an axially movable metallic ground switch contact rod. Axial operation of the ground switch rods is accomplished in synchronism by means of a single operation linked to all the ground switch rods.

It is therefore a general object of the invention to provide a vacuum capacitor switch with ground switch capabilities.

Still another object of the invention is to provide a vacuum capacitor switch having grounding switch means as an integral part of the structure.

Yet another object of the invention is to provide individual ground switches for each phase of a multiphase vacuum capacitor switch carried by the vacuum capacitor switch structure.

A further object of the invention is to provide a vacuum capacitor switch having ground switches and synchronized operating means all integrated on a single structure.

DESCRIPTION OF THE DRAWING FIG. I is a fragmentary view in front elevation of a three-phase vacuum capacitor switch. with one phase omitted, showing the ground switch arrangement for the phases with the operator therefor; and

FIG. 2 is a view in left side elevation of the vacuum capacitor switch. taken along line Illl of FIG. I,

showing the ground switch arrangement as associated with one of the interrupters and which is illustrative of all the ground switches.

DESCRIPTION OF THE INVENTION FIG. I of the drawing shows a three-phase vacuum capacitor switch 20 comprising three vacuum interrupters of which only two of the interrupters 21 and 21A are illustrated since the third interrupter is identical in all respects to the interrupters 2i and 21A. The interrupters 21 and 21A. as well as the third interrupter (not shown). are operated simultaneously by a switch actuator (not shown) that is disposed within a support ing base 25. It is believed that a showing of the interrupter operator is not necessary for a complete understanding of the present invention. However, an operating mechanism suitable for the operation of the interrupters herein depicted is set forth in United States patent application, Ser. No. 278,177. and reference may be had thereto. The vacuum interrupters are identical and are bolted in an upright position on the supporting base 25 which, in turn, is adapted to be mounted on suitable supporting structures (not shown).

The vacuum interrupters 21 and 21A are similar and the description of the interrupter 21 will likewise apply to interrupter 21A and also to the third interrupter (not shown). and corresponding parts will be identified with the same reference number with the addition of a letter suffix to identify the particular interrupters and associated mechanism. The interrupter 2] includes a pair of ceramic hollow upper and

lower insulators

28 and 29 disposed in axial alignment. The lower insulator 29 is mounted in a lower metallic hollow cup member 31 which is bolted to the top surface of the base 25 and is provided with an upper cup member 32. The upper end of the insulator 28 is provided with an upper hollow metallic cup member 34 and is mounted in a lower cup member 33. A metallic terminal 36 having a clearance opening therethrough for the interrupter operating rod is interposed between the

cup members

32 and 33. The upper and

lower insulator members

28 and 29 are rigidly secured together by means of bolts (not shown) which extend through suitable aligned openings provided in terminal 36 and in the radial flanges of

cup members

32 and 33. A metallic cap terminal 38 is bolted or otherwise secured to the upper cup member 34 and serves as a support for a depending stationary contact rod 39 of the vacuum interrupter. The cup members 3I and 32 associated with the lower insulator 29 are bonded thereto by suitable bonding material such as Portland cement. epoxy resin or the like. In like manner, the

cup members

33 and 34 associated with the upper insulator 28 are likewise bonded thereto by the same type of bonding material.

The stationary contact rod 39 extends downwardly into a glass vacuum interrupter 41 that is supported in the hollow upper insulator 28. Vacuum interrupter 4] has a circumferential flange at its lower end which is fastened by screws (not shown) to the metallic terminal 36. A movable contact rod 42 extends through the bottom end of vacuum interrupter 41 and through the opening in terminal 36 in axial alignment with the stationary contact rod 39 and is movable into engagement with stationary contact 39. The movable contact 42 is shown in the open position and is movable axially into abutting engagement with the stationary contact 39 to complete an electrical circuit through the interrupter between

terminals

36 and 38. The ends of vacuum interrupter 41 through which the

contacts

39 and 42 extend are sealed in a well known manner.

An electrical connection is established between movable Contact 42 and the terminal 36 in a well known manner as by a plurality of electrically conductive flexible shunts (not shown). The contact 42 is moved axially in the usual manner by an actuating rod or pushrod (not shown) which is of insulating material that extends upwardly through the insulator 29. The lower end of the push-rod is operatively connected to the actuating mechanism (not shown) within the supporting base 25.

As previously mentioned. each of the phases 21 and 21A, as well as the phase not shown, of the vacuum capacitor switch is provided with a ground switch 51 and 51A. The ground switch is supported by the structure required for the operation of the associated vacuum interrupter. Thus, the need for additional supporting structure is avoided. The ground switches 51 and 51A are identical, thus only a description of the ground switch 51 will be given and such description will also apply to the ground switch 51A and the ground switch (not shown) associated with the third phase vacuum interrupter (not shown).

As shown in the drawings, the ground switch 51 includes a contact cluster 52 which has a plurality of resiliently inwardly biased fingers (not shown). The contact cluster 52 is secured in electrical conducting relationship to an external portion 53 of the terminal 36, as shown in FIG. 2. A metallic grounding rod 54 is supported for movement into and out of engagement with the contact cluster 52. To this end, the contact rod 54 is supported in a pair of

bearings

57 and 58 for axial movement. As shown, the upper bearing support 57 is secured to the top surface of the supporting base and extends outwardly from the side of the base. The lower bearing support 58 is secured to the side of the supporting base 25 with its bearing axis coinciding with the bearing axis of the support 57.

For effecting axial movement of the contact rod 54, the lower end of the rod is formed with a rack 59. A gear 61 rotatably supported on a stub shaft 62, which is supported by and extends outwardly from the side of the supporting base 25, is arranged to mesh with the rack 59. Thus. as viewed in FIG. 1, rotation of the gear 61 in a counterclockwise direction will effect axial downward movement of the contact rod 54 withdrawing it from the contact 52. The travel of the contact rod 54in an opening movement is approximately ten inches which is the preferred gap between the end of the grounding contact rod and the ground contact. To effect rotation of the gear 6!, the gear is mounted on and keyed to a sleeve 63 which is rotatable on the stub shaft 62. On the outer end of the sleeve 63 a bellcrank 64 is mounted and keyed thereto. Actuation of the bellcrank 64 for effecting the rotation of the gear 61 is accomplished in this particular illustrative embodiment by means of a spade handle 66. As shown, the spade handle 66 is pivotally connected to a support which is remote from the supporting base 25. Connecting rod 67 is pivotally connected to the spade handle arm and has its opposite end pivotally connected to the lower arm 68 of the bellcrank 64. Thus, upward pivotal movement 6 feet withdrawal of the end of the grounding contact rod 54 from engagement with the ground contact 52.

As previously mentioned, the

grounding contact rods

54 and 54A, as well as the grounding contact rod (not shown) associated with the third phase vacuum interrupter (not shown), are all actuated simultaneously, both in an engaging and disengaging movement. To this end, a horizontal connecting rod 71 is provided. As shown, the connecting rod 71 has one end pivotally connected to the extending end of an arm 72 of the bellcrank 64. Intermediate the ends of the connecting rod 71 a pivotal connection is effected to the extending actuating arm 72A which is associated with gear 61A. The actuating arm 72A is similar to the arm 72 of the bellcrank 64. The opposite end (not shown) of the connecting rod 71 is pivotally secured to the arm 72A and is also associated with the third phase ground switch (not shown).

Thus, upward movement in an arcuate path of travel of the spade handle 66 will effect the arcuate counterclockwise movement of the arm 68. Counterclockwise movement of the arm 68 will effect counterclockwise rotation of the gear 61 and thereby downward disengaging movement of the grounding contact rod 54. As the arm moves in an arcuate counterclockwise direction, the arm 72 will be moved in the same direction thereby effecting leftward movement of the horizontal connecting rod 71. Leftward movement of the connecting rod 71 will effect counterclockwise pivotal movement of the arm 72A and a similar movement of the arm (not shown) associated with the third phase ground switch (not shown). Thus, the gear 61A will be caused to rotate in a counterclockwise direction to thereby effect the axial downward movement of the grounding contact rod 54A and a like movement of the third phase grounding contact rod (not shown).

Thus, an extremely simple and effective grounding switch arrangement is provided for a multiphase vacuum capacitorswitch which requires no additional supporting structure or insulators but utilizes the supporting and insulator structures of the vacuum capacitor switch itself. The arrangement provides for maximum safety since the grounding switches are closely adjacent to the individual vacuum interrupters, and their physical condition can thereby be readily observed. The simplicity of the arrangement provides for a minimum of operating parts, thereby reducing maintenance and installation costs.

Since the

grounding contact rods

54 and 54A are movable axially, flexible grounding straps 76 and 76A or moving contacts are securely attached to the lower ends of the

rods

54 and 54A. The flexible grounding straps 76 and 76A are grounded to the supporting base 25 or may be connected to another grounded structure as desired.

The embodiments of the invention in which an exclusive property or priviledge is claimed are defined as follows:

1. In a multiphase vacuum capacitor switch having a supporting base;

a plurality of vacuum interrupters each of which has a pair of separable contacts one of which is stationary and the other of which is movable into and out of engagement with said stationary contact;

a grounding contact associated with each vacuum interrupter, said grounding contact being supported by its associated vacuum interrupter and in electrical conducting relationship with the movable contact of the vacuum interrupter;

a grounded contact rod for each of said vacuum interrupters. said grounded contact rods being carried by said supporting base in position to engage with an associated grounding contact;

operating means connected to said grounding contact rods for effecting the simultaneous movement of said grounding contact rods; and,

a single actuator connected to said operating means for effecting operation of said operating means. 2. In a multiphase vacuum capacitor switch having a upporting base;

a plurality of vacuum interrupters carried by said supporting base in vertical parallel array, said interrupters each having a pair of separable contacts, one of which is stationary. and the other of which is axially movable into and out of engagement with the associated stationary contact;

a plurality of grounding switches carried by said supporting base, said grounding switches each having a contact carried by an associated vacuum interrupter externally thereof, said contact having an electrical conducting connection with the movable contact of its associated vacuum interrupters, said grounding switches each also having a movable grounded contact rod carried by said supporting base for movement into and out of engagement with the associated contact carried exteriorly of the vacuum interrupter;

a rack formed on each grounded contact rod;

a gear rotatably carried by said supporting base for each grounded contact rod, said gears being disposed in meshed engagement with an associated grounded contact rod rack;

drive means interconnecting all of said gears in a manner that rotation of one of said gears will effect rotation of all of said gears simultaneously; and,

actuating lever means connected to one of said gears to effect its rotation for engaging or disengaging said grounded contact rods with the associated contacts carried by said vacuum interrupters exteriorly thereof. 3. In a multiphase vacuum capacitor switch comprising:

a grounded supporting base;

multiple spaced apart insulators mounted on said supporting base;

a vacuum interrupter mounted on each of said insulators;

a stationary contact and a movable contact supported within each of said vacuum interrupters for make-and-break engagement;

a first terminal for each of said vacuum interrupters, said first terminals being secured to the upper free end of an associated vacuum interrupter in electrical connection with an associated stationary contact;

a second terminal for each of said vacuum interrupters. said second terminals being secured to the lower end of said associated vacuum interrupters in electrical connection with an associated movable contact;

a grounding switch for each vacuum interrupter carried by said supporting base in operative association therewith, each of said grounding switches includes a resilient grounding contact and a grounded contact rod that is engageable with said grounding contact, said grounding contact being mounted on said second terminal in electrical relationship therewith and in position to receive said contact rod, said contact rod is supported to said supporting base for axial movement into and out of engagement with said grounding contact;

means for operating said grounding switches including a rack formed on each of said contact rods and a gear rotatably supported by said supporting base and in engagement with an associated rack; and,

a single means for effecting the rotation of said gears for moving said contact rods simultaneously into and out of engagement with their associated grounding contacts.

Claims

1. In a multiphase vacuum capacitor switch having a supporting base; a plurality of vacuum interrupters each of which has a pair of separable contacts one of which is stationary and the other of which is movable into and out of engagement with said stationary contact; a grounding contact associated with each vacuum interrupter, said grounding contact being supported by its associated vacuum interrupter and in electrical conducting relationship with the movable contact of the vacuum interrupter; a grounded contact rod for each of said vacuum interrupters, said grounded contact rods being carried by said supporting base in position to engage with an associated grounding contact; operating means connected to said grounding contact rods for effecting the simultaneous movement of said grounding contact rods; and, a single actuator connected to said operating means for effecting operation of said operating means.

2. In a multiphase vacuum capacitor switch having a supporting base; a plurality of vacuum interrupters carried by said supporting base in vertical parallel array, said interrupters each having a pair of separable contacts, one of which is stationary, and the other of which is axially movable into and out of engagement with the associated stationary contact; a plurality of grounding switches carried by said supporting base, said grounding switches each having a contact carried by an associated vacuum interrupter externally thereof, said contact having an electrical conducting connection with the movable contact of its associated vacuum interrupters, said grounding switches each also having a movable grounded contact rod carried by said supporting base for movement into and out of engagement with the associated contact carried exteriorly of the vacuum interrupter; a rack formed on each grounded contact rod; a gear rotatably carried by said supporting base for each grounded contact rod, said gears being disposed in meshed engagement with an associated grounded contact rod rack; drive means interconnecting all of said gears in a manner that rotation of one of said gears will effect rotation of all of said gears simultaneously; and, actuating lever means connected to one of said gears to effect its rotation for engaging or disengaging said grounded contact rOds with the associated contacts carried by said vacuum interrupters exteriorly thereof.

3. In a multiphase vacuum capacitor switch comprising: a grounded supporting base; multiple spaced apart insulators mounted on said supporting base; a vacuum interrupter mounted on each of said insulators; a stationary contact and a movable contact supported within each of said vacuum interrupters for make-and-break engagement; a first terminal for each of said vacuum interrupters, said first terminals being secured to the upper free end of an associated vacuum interrupter in electrical connection with an associated stationary contact; a second terminal for each of said vacuum interrupters, said second terminals being secured to the lower end of said associated vacuum interrupters in electrical connection with an associated movable contact; a grounding switch for each vacuum interrupter carried by said supporting base in operative association therewith, each of said grounding switches includes a resilient grounding contact and a grounded contact rod that is engageable with said grounding contact, said grounding contact being mounted on said second terminal in electrical relationship therewith and in position to receive said contact rod, said contact rod is supported to said supporting base for axial movement into and out of engagement with said grounding contact; means for operating said grounding switches including a rack formed on each of said contact rods and a gear rotatably supported by said supporting base and in engagement with an associated rack; and, a single means for effecting the rotation of said gears for moving said contact rods simultaneously into and out of engagement with their associated grounding contacts.