US3454734A - Compressed-gas circuit interrupter - Google Patents

Description

July 8, 1969 R. G. COLCLASER, JR., ET AL 3,454,734

COMPRESSED-GAS CIRCUIT INTERRUPTER Shet Filed Sept. 22, 1965 er, Jr..0nd

x o y w? m m Em k m m l Y C v. H M mm 23 I 0 OINS 3 mm ATTORNEY COMPRESSED-GAS C IRCUIT INTERRUPTER Sheet Filed Sept. 22, 1965 HIGH PRESSURE 2 G F .m 3 3 3 "w 0 T 4 3 5 fl m A q a 4 m H 5 v Q 7 j x H N M x/ 5 I 3 4 1 3 W N U l W 6 l R P July 8, 1969 R. s. COLCLASER, JR. ET AL COMPRESSED- (ms CIRCUIT INTERRUPTER Sheet 1 Filed Sept. 22, 1965 FIG. 3.

m o 3 a w u C 5 3a 5 34 5 m A. 5 u 3 3 42 w u w A an 3 ||||M\ V y 2 a 5 w w m y 5 vvvlll m f m :vm w llll cocoa O 4 7 3 4 I 2 h w I 1 3 4 /.W. W 5 5 4 N w u United States Patent Otfice COMPRESSED-GAS CIRCUIT INTERRUPTER Robert G. Colclaser, Jr., Franklin Township, Delmont,

and Russell N. Yeckley, Murrysville, Pa., assignors to Westinghouse Electric Corporation, Pittsburgh, Pa., a

corporation of Pennsylvania Filed Sept. 22, 1965, Ser. No. 489,228 Int. Cl. H01h'33/82 US. Cl. 200-148 11 Claims ABSTRACT OF THE DISCLOSURE This invention relates, generally, to compressed-gas circuit interr'upters and, more particularly, to compressed-gas circuit interrupters having interrupting units enclosed within pressurized tanks.

A general object of the present invention is to provide an improved compressed-gas circuit interrupter of the presurized-tank type, which is highly effective, may be utilized in multiple modular form, and, in addition, uses a downstream blast-valve construction.

A more specific object of the present invention is to provide an improved pressurized-tank type of compressed-gas circuit interrupter in which a movable tubular contact moves along an exhaust passageway, the flow of gas through which is controlled by a downstream blast valve.

Still a further object of the present invention is to provide an improved pressurized-tank type of high-voltage compressed-gas circuit interrupter in which a tank means is supported up in the air by an insulating column, the tank means containing a pressurized gas, and one or more serially-related arc-extinguishing units are disposed interiorly of the tank means, each unit containing a movable tubular contact movable along an exhaust passageway, and pneumatically connected with a down stream blast valve.

Prior circuit breakers for extra-high-voltage service are of the live tank type where the insulation to ground is supplied by a porcelain supporting column instead of by a gaseous medium. Also in prior- SF breakers of the dual-pressure type, the SF 'gaS is stored in a high-pressure chamber and admitted through an upstream blast valve into an interrupting unit, or units disposed within a low-pressure chamber.

Another object of this invention is to provide a circuit breaker which may include one interrupting unit, or two or more units connected in series, each unit being enclosed within a metal pressurized tank, which is supported and insulated from ground by a supporting column composed of porcelain or other insulating material.

Another object of the invention is to provide a circuit breaker of the dual-pressure type in which each interrupting unit is enclosed in a tank containing an interrupting gas at a relatively high pressure, and which is exhausted through a downstream blast valve into a lowpressure chamber during an interrupting operation.

steel tank 14,

Patented July 8, 1969 A further object of the invention is to provide a double-break interrupter having two relatively stationary contact members and two series connected tubular movable contact members having an exhausting flow of gas therethrough.

Still another object of the invention is to provide a double-break interrupter having two series connected movable tubular contact members which are moved in opposite directions during an interrupting operation.

A still further object of the invention is to utilize one downstream blast valve to cause an interrupting gas to flow through two series-connected hollow moving contact members of an interrupter.

Other objects of the invention will be explained fully hereinafter, or will be apparent to those skilled in the art.

In accordance with one embodiment of the invention, the contact assembly of a double-break interrupter is enclosed in a steel tank containing sulfur hexafiuoride, (SF gas at a relatively high pressure. The tank is supported and insulated from ground by an upstanding insulating column containing SF gas at a relatively low pressure. A spring-biased downstream blast valve normally closes the entrance to the upstanding column. During an interrupting operation, gas flows downwardly from the pressurized tank through two series-connected, hollow, rotatable contact members and a downstream blast valve into the upstanding supporting column, thereby interrupting the arcs drawn between the moving contact members and the stationary contact members.

For a better understanding of the nature and objects of the invention, reference may be had to the following detailed description, taken in conjunction with the accompanying drawings, in which:

FIGURE 1 is a diagrammatic view of a circuit-breaker structure embodying principal features of the invention.

FIG. 2 is a view, partly in elevation, and partly in section, of one pole units of the breaker shown in FIG. 1, the contacts being shown in the closed-circuit position;

FIG. 3 is a fragmentary View, somewhat similar to that of FIG. 2, but illustrating the position of the movable contact members during an opening operation; and,

FIG. 4 is a diagrammatic view of the hydraulic actuating mechanism for eflFecting opening of the contact structure.

Referring to the drawings, and more particularly to FIG. 1 thereof, the circuit-breaker structure 10 shown therein includes two interrupting assemblies 11 and 12 which are connected in series-circuit relation through a conductor 13. The interrupting assemblies 11 and 12 constitute one pole-unit 10. As many pole units 10 as desired may be provided. Thus, in a three-phase power system, three pole-units 10, similar to the one illustrated, would be required. Furthermore, one or a plurality of interrupting assemblies 11, 12 may be provided for each pole-unit 10 depending upon the voltage of the power system.

The interrupting assembly 11 comprises a pressurized which is supported and insulated from ground by an upstanding porcelain column 15 mounted upon a base housing 16. As indicated in FIG. 2, the base housing 16 contains a high-pressure tank 18, a compressor unit 19, and a hydraulic mechanism compartment 20.

A terminal bushing 21 is mounted upon an angularlyextending collar 22 on the pressurized tank 14. A similar bushing 23 is mounted upon a horizontally-extending collar 24 on the tank 14. The interrupting assembly 12 is similar to the assembly 11 except that the bushings 21a and 23a and the collars 22a and 24a extend in different directions on the tank 14a from the directions of the corresponding members on the tank 14.

As indicated in FIG. 2, the pressurized tank 14 contains an interrupting gas, such as sulfur hexafiuoride (SP gas, at a relatively high pressure, for example, 200 p.s.i.g. The supporting column 15 contains sulfur hexafluoride (SP gas at a relatively low pressure such as 30 p.s.i.g. An opening 25 between the tank 14 and the column 15 is normally closed by a downstream blast valve 26, which is biased to the closed position against a valve seat 27 by a compression spring 28. Low-pressure SP gas is drawn from the column 15, compressed by the compressor 19 and supplied to the interior of the tank 14 through an insulating tube 29 disposed inside the supporting column 15. The bushings 21 and 23 may be gas-filled, oil-filled, or shellac-impregnated, as desired.

The current path through the interrupting assembly 11 extends from the bushing 21 through relatively stationary contact fingers 31 mounted in a contact foot 32 on the inner end of the terminal bushing 21, a hollow movable contact member 33, which is engaged by the fingers 31, and is carried by a rotatable arm 34, a springbiased contact member 35, which bridges the arm 34, and a similar arm 340, a hollow contact member 33a carried by the arm 34a, contact fingers 31a and a contact foot 32a secured to the terminal bushing 23. Thus, the movable tubular contact members 33 and 33a are connected in series-circuit relation, and the assembly 11 is of the double-break type since two interrupting gaps are provided between the two movable tubular contact members 33, 33a and their associated stationary contact members 31, 31a.

The moving contact assembly is supported by a metal casting support 36 mounted upon a support member 37, which, in turn, is mounted upon the upper end of the insulating supporting column 15 and provides an exhaust passageway 37. The rotatable contact arms 34 and 34a are mounted upon pivot pins 38 and 38a, respectively, which are mounted in the metal support casting 36. The arms 34 and 34a are connected by links 39 and 39a respectively, to a rotatable crank-arm 41 on an operating drive shaft 42. The drive shaft 42 extends to the outside of the pressurized tank 14 through a suitable shaft seal (not shown), and may be driven by any suitable operating mechanism of a type well known in the art. The casting 36 may be made in. two halves, one of which is shown in the drawing.

As shown in FIG. 4, the drive shaft 42 extends through the outer side wall of the pressurized metallic tank 14 and is actuated in the opening and closing directions by a hydraulic mechanism 70, comprising a hydraulic cylinder 71, within which moves a hydraulic piston member 72. The hydraulic piston member 72 is connected to a piston rod 73 pivotally connected, as at 74, to a crank-arm 75 affixed to the external end of the operating drive shaft 42.

A hydraulic line 78 interconnects the upper end of the hydraulic cylinder 71 with an operating master valve, generally designated by the reference numeral 79, disposed within the mechanism compartment 20 at ground potential, and which is electrically actuated by a doublesolenoid device 80 also at ground potential. As shown in FIG. 4, the double-solenoid device 80 comprises a pair of armatures 81, 82, associated with energizing windings 83, 84, which may be energized by the closing of an open push-button 90, or the closing of a close push button 91, as shown in FIG. 4.

Operation of the hydraulic master valve 79 at ground potential within mechanism compartment 20 will interconnect the high-pressurev hydraulic fluid from an accumulator 85 through the master hydraulic valve 79, and into the particular end of the hydraulic cylinder 71 depending on which particular operating button 90, 91, is pressed. Also, as well known by those skilled in the art, a sump 94 may be provided to be connected to the end of the hydraulic operating cylinder 71 in which the pressure is to be reduced.

FIG. 4 shows the electrical operating conditions at the end of the closing operation of the circuit interrupter 10. It will be noted that the closing button 91 has energized the solenoid 84 to effect rotation of the master valve 79 to the position indicated, whereby the accumulator is connected to the lower end of the hydraulic cylinder 71, thereby forcing the hydraulic piston 72 upwardly, and effecting a closing operation of the driving crank 75. This will close the movable contacts 33, 33a as shown in FIG. 2.

The downstream blast valve 26 is essentially of the balanced type, and is held closed against the valve seat 27 by the compression spring 28. The blast valve 26 has a skirt 43 surrounding an upwardly extending portion 44 on the support member 37. An exhaust opening 45 in the support 37 provides an exhaust passageway from the interior of the tank 14 into the upstanding insulating column 15 when the blast valve 26 is lowered to open the valve opening 25. The blast valve 26 has a stem 46, which extends upwardlly through a valve guide 47 in the metal casting 36. The upper end of the valve stem 46 has a plurality of ratchet teeth 48 provided thereon. The teeth 48 are engaged by a spring-biased pawl 49 carried by a bifurcated rod 51 pivotally attached to the crank-arm 41 by a pin 52, which also attaches the links 39 and 39a to the crank arm 41. Thus, the blast valve 26 is opened simultaneonsly with the contact members 33, 33a of the interrupter 11, as will be described more fully hereinafter.

The contact member 35, which bridges hub portions of the contact arms 34 and 34a is disposed within a recess in the metal casting 36, and is biased into engagement with the hub portions by compression springs 53. As previously explained, the bridging member 35 electrically connects the moving contact members 33 and 33a in series-circuit relation.

The hollow contact members 33 and 33a are arcuate in shape since each moves in an arc defined by the rotatable contact arm 34 or 34a along the exhaust passageway 37'. The metal casting member 36 has arcuate passageways 54 and 54a therein for receiving the moving contact members 33 and 330, respectively. The passageways 54 and 54a communicate with the blast valve opening 25, which, in turn, communicates with the in-' terior of the supporting column 15 through the opening 45 in the support member 37.

An opening operation is as follows: Upon receipt of the proper signal, the operating shaft 42 is rotated clock- Wise by the operating mechanism, thereby moving the crank-arm 41 downwardly. This rotates the contact arms 34 and 34a in opposite directions through the links 39 and 39a, respectively, thereby disengaging the contact members 33 and 33a from the stationary contact fingers 31 and 31a, respectively. Arcs are established, which quickly transfer to are horns 55 and 55a, respectively, as indicated by the arcs 56 in 'FIG. 3. At the same time, the downward motion of the crank-arm 41 drives the blast valve 26 downwardly through the ratchet assembly 48, 49. This causes high-pressure sulfur-hexafiuoride (SP gas to flow from the interior of the tank 14 through the hollow contact members 33 and 33a, the exhaust passageway 37', the valve opening 25, and the passageway 45 into the low-pressure chamber inside the upstanding insulating column 15. Thus, the hollow moving contact members 33, 33a serve as orifices for the gas flow. This flow of gas effects arc interruption in a manner somewhat similar to that described in Patent No. 3,154,658, issued Oct. 27, 1964 to G. Colclaser and R. N. Yeckley and assigned to the assignee of the instant application.

As described in the aforesaid patent, there is provided an axial flow of gas through the mouth of the orifice contacts 33, 33a, but also there is provided a cross-blast action of the gas, since the arc is drawn between the tip portion of the arcing horn and the inner side wall of the movable hollow contact, as shown by the arcs 56 in FIG.

3. As a result, there is provided both a cross-blast action and an axial flow blast action of the gas during an interruption operation.

Downward motion of the blast valve 26 is stopped by a projection 57 engaging a butter assembly 58 in the portion 44 of the supporting member 37. Just prior to reaching the full-open position, the pawl 49 is disengaged from the ratchet teeth 48 by a pin 59, thereby permitting the blast valve 26 to be reclosed by its biasing spring 28. In this manner, the quantity of the high-pressure interrupting gas used during an interruption is' conserved. As previously explained, gas is drawn from the lowpressure chamber inside the column and returned by the compressor 19 through the insulating tube 29 to the high-pressure chamber inside the metal tank 14.

From the foregoing description it is apparent that the invention provides a live-tank breaker, with contacts operated in a high-pressure gas, such as sulfur-hexafluoride (S1 gas, resulting in a structure of minimum required contact separation. More efiicient use of the gas is obtained, when compared to prior breakers of the dualpressure type, with a possible resultant of lower maximum gas pressures, and a corresponding reduction in auxiliary heater requirements. The double-break interrupter unit 11 is suitable for use at relatively high voltages, and, as previously explained, two or more interrupting assemblies 11, 12 may be connected in seriescircuit relation, thereby further increasing the service voltage. Minimum mass is accelerated, resulting in reduced mechanism requirements. The downstream blast valve arrangement makes high-pressure gas available right at the contacts, and two-cycle operation is easier to obtain than with upstream valve arrangements.

Reduced tank size is feasible because of the excellent dielectric property of the high-pressure sulfur-hexafluoride (SP gas or other interrupting gas. Maintenance is simplified since only the high-pressure gas need be removed to gain access to the interior of the tank 14, the blast valve 26 effectively sealing the low-pressure side. The operating mechanism 70 can be serviced without disturbing the gas since it is mounted exteriorly of the pressurized tank 14.

Since numerous changes may be made in the abovedescribed construction, and different embodiments of the invention may be made without departing from the spirit and scope thereof, it is intended that all subject matter contained in the foregoing description, or shown in the accompanying drawing, shall be interpreted as illustraive and not in a limiting sense.

We claim as our invention:

1. A double-break circuit interrupter comprising a spherical tank containing an interrupting gas at a relatively high pressure, a column supporting and insulating the spherical tank from ground, a single spring-biased blast valve normally closing an opening between the tank and the column, two spaced relatively stationary contact members disposed inside the tank adjacent opposite ends thereof, two series-connected hollow rotatably movable contact members engaging the stationary contact members, a pair of rotatable crank-arms (34) carrying the movable contact members, operating means for disengaging the contact members in a rotatable fashion and opening the single blast valve to cause gas to flow from the spherical tank through the hollow contact members and through the single valve opening into the supporting column to interrupt the arcs drawn between the separated contact members, and the axis of rotation (38) for the rotatable crank-arm (34) being in close proximity to the center of the spherical tank.

2. A double-break circuit interrupter comprising a tank containing an interrupting gas at a relatively high pressure, a column supporting and insulating the tank from ground, a spring-biased blast valve normally closing an opening between the tank and the column, two spaced relatively stationary contact members disposed inside the tank, two series-connected hollow rotatable contact members engaging the stationary contact members, and operating means for driving the rotatable members toward each other to disengage them from the stationary contact members and for opening the blast valve to cause gas to flow from the tank through the hollow contact members and the valve opening into the supporting column to interrupt the arcs drawn between the separated contact members.

3. A double-break circuit interrupter comprising a metal tank containing an interrupting gas at a relatively high pressure, a column supporting and insulating the metal tank from ground, a spring-biased blast valve normally closing an opening between the metal tank and the column, two spaced relatively stationary contact members disposed inside the tank, two series-connected hollow rotatable contact members engaging the stationary contact members, operating means for driving the rotatable members toward each other to disengage them from the stationary contact members and to open the blast valve to cause gas to flow from the metallic tank through the hollow contact members and the valve opening into the supporting column to interrupt the arcs drawn between the separated contact members, and means permitting the blast valve to be reclosed by its biasing spring at the end of the opening operation.

4. A double-break circuit interrupter comprising a metal tank containing an interrupting gas at a relatively high pressure, a column supporting and insulating the tank from ground, a spring-biased blast valve normally closing an opening between the tank and the column, two spaced relatively stationary contact members disposed inside the tank, two series-connected hollow rotatable contact members engaging the stationary contact members, operating means for driving the rotatable members toward each other to disengage them from the stationary contact members, ratchet means actuated by the operating means to open the blast valve to cause gas to flow from the tank through the hollow contact members and the valve opening into the supporting column to interrupt the arcs drawn between the separated contact members, and means for releasing the ratchet means to permit the valve to be reclosed by its biasing spring at the end of the opening operation.

5. In a double-break circuit interrupter, in combination, a spherical metallic tank containing an interrupting gas at a relatively high pressure, a hollow column for supporting and insulating the tank from ground, two relatively stationary contact members mounted inside the tank in spaced relation, a supporting member disposed between said contact members and having an exhaust passageway therethrough with a single valve open-ing communicating with the interior of the column, a single spring-biasing downstream blast valve normally closing said single valve opening, a hollow rotatably movable contact member engaging each stationary contact member, a pair of rotatable crank-arms (34) carrying the movable contact members, operating means for moving the hollow contact members into said exhaust passageway to disengage them from the stationary contact members and for opening the single downstream blast valve to cause gas to flow from the tank through the hollow contact members and the single valve opening into the supporting column, and the axis of rotation (38) for the rotatable crank-arms (34) being in close proximity to the center of the spherical tank.

6. In a double-break circuit interrupter, in combination, a metallic spherical tank containing an interrupting gas at a relatively high pressure, a hollow column for supporting and insulating the tank from ground, two relatively stationary contact members mounted inside the tank in spaced relation adjacent opposite ends thereof, a centrally-located supporting member disposed between said contact members and having an exhaust passageway therethrough with a single valve opening communicating with the interior of the column, a single spring-biased downstream blast valve normally closing said single valve opening, a hollow contact member engaging each stationary contact member, a contact arm rotatably mounted on the centrally-located supporting member for carrying each hollow contact member, and operating means for driving the contact arms in opposite directions to disengage the hollow contact members from the stationary contact members and move them into said passageway, said operating means also opening said single blast valve to cause gas to flow from the tank through the hollow contact members and the single valve opening into the supporting column, and the axis of rotation (38) for the rotatable contact arms (34) being in close proximity to the center of the spherical tank.

7. In a double-break circuit interrupter, in combination, a metallic tank containing an interrupting gas at a relatively high pressure, a hollow column for supporting and insulating the tank from ground, two relatively sta tionary contact members mounted inside the tank in spaced relation, a supporting member disposed between said contact members and having an exhaust passageway therethrough with a single valve opening communicating with the interior of the column, a single spring-biased blast valve normally closing said single valve opening,- a hollow rotatable contact member engaging each stationary contact member, a contact arm rotatably mounted on the supporting member for carrying each hollow rotatable contact member, a bridging contact member engaging the rotatable contact arms to electrically conmeet the hollow contact members in series-circuit relation, operating means for driving the rotatable contact arms in opposite directions to disengage the hollow contact members from the stationary contact members and move them into said exhaust passageway, and ratchet means driven by the operating means to open the single downstream blast valve to cause gas to flow from the tank through the hollow contact members and the valve opening into the supporting column.

8. In a double-break circuit interrupter, in combination, a metallic tank contain-ing an interrupting gas at a relatively high pressure, a hollow column for supporting and insulating the tank from ground, two relatively stationary contact members mounted inside the tank in spaced relation, a centrally-located supporting member disposed between said contact members and having an exhaust passageway therethrough with a single valve opening communicating with the'interior of the column, a single spring-biased downstream blast'valve normally closing said single valve opening, a hollow rotatable contact member engaging each stationary contact member, a contact arm rotatably mounted on the supporting member for carrying each hollow rotatable contact member, a bridging contact member engaging the contact arms to electrically connect the hollow rotatable contact members in series-circuit relation, operating means for driving the contact arms in opposite directions to disengage thehollow rotatable contact members from the stationary contact members and move them into said exhaust passage- Way, ratchet means driven by the operating means to I exhaust passageway, means defining a pair of arc-extinguishing units disposed within said spherical tank means and comprising each a relatively stationary contact carried by the interior end of one of said terminal bushings and a cooperable rotatably movable tubular contact movable along said exhaust passageway, a rotatably movable crank-arm (34) for moving each movable contact, means defining a single centrally-located downstream blast valve communicating with said exhaust passageway and exhausting into the supporting insulating column,

- means including a rotatable drive-shaft (42) extending through the wall of said tank means for effecting separation of the pair of movable tubular contacts and opening of said single downstream blast valve, means for effecting rotation of said drive-shaft externally of said tank means, whereby an exhausting flow of highpressure gas will flow out of said spherical tank means through the pair of movable tubular contacts and past the single opened blast valve into the insulating supporting columns for arcextinguishing purposes, and the axis of rotation (38) for the rotatable contact arms (34) being in close proximity to the center of the spherical tank.

10. The combination according to claim 9, wherein a releasable ratchet means interconnect opening driving motion of said drive shaft and opening motion of a blastvalve stem.

11. The combination of claim 9, wherein hydraulic means at high potential disposed externally of the metallic tank means and operated at ground potential causes rotation during the opening and closing operation of the rotatable drive-shaft (42).

References Cited UNITED STATES PATENTS 2,454,586 11/1948 Amer. 3,275,778 9/1966 Morioka. 3,284,602 11/ 1966 Friedrich et al.

3,327,082 6/1967 Van Sickle et a1. 3,356,809 12/1967 Colclaser et a1.

FOREIGN PATENTS 1,1174,400 7/ 1964 Germany.

ROBERT S. MACON, Primary Examiner.

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