CA1107795A - Tank-type compressed-gas circuit-interrupter of the puffer type having improved assembly features - Google Patents

Abstract

IMPROVED TANK-TYPE COMPRESSED-GAS
CIRCUIT-INTERRUPTER OF THE PUFFER TYPE
HAVING IMPROVED ASSEMBLY FEATURES
ABSTRACT OF THE DISCLOSURE
An improved grounded-tank-type of compressed-gas circuit-interrupter is provided having improved assembly features for making provision for a separate subassembly of the gas-interrupter gas modules, with their actuating link-age affixed to a mounting support plate. Subsequently, as a subsequent separate assembly operation, the said mounting support-plate constitutes tile lower closure member of an upstanding metallic grounded outer tank assembly, which is dropped, as a final assembly operation, over the aforesaid subassembly and bolted thereto.
Another feature of the instant invention includes the upper curved dome portion of the outer tank having a predetermined radius of curvature, with the two terminal-bushing flange-rings making flush attachment to the tank, and having the center-line of the two terminal-bushings being normal to the curvature of the upper curved dome portion. Thus, the divergence angle between the two ter-minal-bushings is predetermined in the proper manner, and ready assembly of the terminal-bushings is thereby achieved without the use of adaptors, or coupling ring members, as required heretofore.
Preferably, the operating mechanism housing, together with its internally-located operating mechanism, is attached to the side of the outer upstanding metallic tank, and the mechanical interconnection between the operating mechanism and the previously-mentioned actuating linkage for the gas-modular units is readily made, without requiring critical alignment, or accurate positioning of the several parts.
Another feature of the invention is the use of a relatively-short, non-magnetic insert-strip extending be-tween the two aforesaid flange-rings for supporting the terminal-bushings, thereby minimizing concomitant eddy-current heating losses.
Still another feature of the invention is the use of a suitable non-magnetic material, such as non-magnetic stainless steel, for example, for fabricating the upper dome portion of the grounded tank structure itself.

Description

~ROSS-~EF~R~r,C~S TO A RELATED APPLICATION L ~ PATENTS
Reference ma~J be made to Canadian Patent Application Serial Mo. 265,793 filed Mo-vember 16, 1976 by T. _. Alverson et al, entitled "Circuit Breaker"; United States Patent No.
4,110,578 issued August 29, 1978 to Russell M. Yeckley et al, entitled "Circuit Breaker"; United States Patent No. 4,075,447 issued February 21, 1978 to Joseph R. Rostron, entitled "Double-Puffer-Type Compressed-Gas Circuit-Interrupter Constructions", ard United States Patent No. 3,987,262 issued October 19, 1976 to Joseph R. RostronO

77~5 SUMMARY OF THE T NVENTION
In accordance w~th the present invention, there is provided an improved grounded-tank-type Or compressed-gas circult-interrupter lnvolving lmproved assembly features.
The aforesaid assembly reatures include the inltial sub-assembly operation Or a pair Or modular purfer-type gas-units, together with their actuat~ng linkage, supported and arfixed to a relatively-heavy metallic support plate.
As a subsequent final assembly operation, the outer grounded tank is dropped over the aforesaid initially-constructed subassembly apparatus, and bolted to the afore-said relatively-heavy support ring. Preferably, the outer tank itself constitutes a supporting means for a laterally-adjacently-provided mechanism housing carrying therewithin the breaker operating mechanism itself The proper divergence angle between the two ter-minal-bushings, when the latter are used, is provided by the center-line Or the terminal-bushing being normal to the radius of cur~ature of the upper dome portion o~ the outer - 20 metallic grounded tank. Thus, assembly ~s readily achleved without attention being paid to the alignment of the ter-minal-bushings, for regardless of the orlentatlon, the ~ ~ 46,715 proper divergence angle between the two terminal-bushings is, in any event, properly achieved.
To minimize eddy-current heating losses, there is preferably provided a non-magnetic insert-strip extending between the two supporting flange-rings disposed at the upper end of the outer tank. When the current rating of the circuit-interrllpter i.s additionally uprated, if desired, substantially the entire upper dome portion of the outer tank itself may be fabricated of a suitable non-magnetlc material, such as non-magnetic stainless steel, for example.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a vertical sectional view taken through an improved tarlk-type compressed-gas circuit-inter-rupter embodying the principles of the present invention, and the circuit-breaker being shown in the closed-circuit position;
Figure 2 is a top plan view, considerably-enlarged, of the outer metallic grounded ta.nk with the terminal-bushings removed for clarity, and indicating the use of a non-magnetic insert strip interconnectlng the bushing-flange ring~;
Figure 3 is an enlarged vertical sectional view taken through the subassembly, involving two modular gas-units, together with their connecting operating linkage attached to a relatively-heavy mounting support-plate;
Figure 4 is a considerably-enlarged, side-eleva-tional view of the two modular units arranged in electrical series, the left-hand modular unit being shown in slde eleva-tion, whereas the right-hand modular, puffer-type, interrupt-ing unit is shown in vertical section, the contact structure being illustrated in the fully-open-circult posltion;
~ igure 5 ls a considerably-enlarged vlew of the upper statlonary contact structure of each of the modular, puffer-type, arc-extingulshlng unlts, indicating the adapt-abillty for varlous line-termlnal connections;
Flgure 6 lllustrates an alternate form of llne-termlnal connectlon, ln wlllch the statlonary contact struc-ture of the left-hand modular unlt ls electrlcally connected to the li.ne-conductor of the gas-insulated transmlsslon system, Figure 7 lllustrates a fragmentary top plan vlew looking downwardly between the two terminal-bushings, and illustrating the non-magnetic insert-strip extending between the two terminal-bushlng flange-rlngs;
Figure 8 iæ a fragmentary vertical sectional view taken through a modified-type of tank construction, in which the upper dome portlon ls fabricated of a suitable non-m~gneti.c material, such as stainless steel, for example;
Figure 9 is a fragmentary vertical sectional view, indicating the radius of curvature of the upper dome portion of the tank structure of Figs. 1, 2 and 7, indicating that the flange-rings, for accommodating the terminal-bushings, are disposed such tha.t their center-line is normal, or per-pendi.cular to the curvature of the upper dome portion of the tank; and Figure 9A is a considerably-enlarged, fragmentary view of a portion of the welding surface for the flange-ring of Fig. 9, indicating a ccmparison between the older flange-ring construction and the new flange-r~ng construction.

IJ~, ;15 ~L~LQ77~5 DESCRIPTION OF THE PREFERRED EMBODIMENTS
._ .
Referrlng to the drawings, and more particularly to F~gures 1 and 2 thereof, it will be observed that Figure 3 illustrates a subassembly 1 comprising a pair of con-~ointly-acting gas-modules 2 of the type set forth in the U.S. patent ~123,636 issued October 31, 197 and ~ssigned to the assignee of the instant p.~tent applicatlon. As shown, the two gas modules 2 are electrically and mechanically tied together by a horizontally-extendin~ brldging-bar construction 4 havlng pivotally connected thereto, as at ~, an upstandlng maln insulating operating rod 6.
The operating rod 6 is, as shown, pivotally con-nected at 7 to a. bell-crank lever 8, which is affixed to a rotatable main operating shaft 9. A lever box 10 is affixed, as by weldlng 3, for example, to the lower surface 11 Or the main metallic support-plate 12.
Each of the gas-modular units 2 comprises an upper relatively-stationary contact str~cture 13 including a cluster Or a.nnularly-arranged main stationary contact fingers 14, which, in the closed-circuit position of the interrupter, as indicated in Figure 1, make good contacting engagement with an annular movable main contact 15 affixed to an operating-cylinder assembly 17, the latter moving downwardly during the opening operation over a relatively-fixed piston structure 18.
Centrally disposed within the cluster of rela-tively-stationary main contact fingers 14.is a tubular stationary arcing contact 20, which makes engagement with a plurality of secondary movable arcing contact fingers 22, 46,715 77~7S~S

the movable arcin~ rod-shaped contact 23 extending there-within.
Constituting a part of the movable operating-cylinder a.ssembly 17 is an insulating hollow orif1ce 25, which directs the gas flow emanating from the compression space 30, interposed between the stationary plston structure 18 and the outer-disposed movable operating cylinder 17.
This gas ~low strikes the established arc 35, as lndicated ln Figure 3, and effects the rapid extinction thereof.
As will be obvious, the two modular gas-units 2 operate simultaneously by their downward cooperative move-ment, and, in electrical series, constitute an electrical piece of interrupting equipment having a voltage rating of 242 Kv with an interrupting capacity of 50 to 63,000 amperes, for example. The full-load continuous current rating of the circuit-interrupter~ for example, would be 2,000 to 4,000 amperes.
As illustrated in Figure 3, the two modular units

2 are collectively supported by an upstanding insulating support cylinder 40, which, in turn, is ~ixedly bolted to the relatively-heavy metallic support-plate 12, referred to hereinbefore Fol.lowing subassembly of the interrupting equip-ment 1, ~llustrated in Figure 3, the grounded metallic tank struc'cure 41 is lifced up and dropped over the subassembly, designated by the reference numeral 1. The heavy metallic support-plate 12 is secured by a plurality of clrcumfer-entially-disposed bolts 45 to the underside of a heavy mounting ring 46, which, in turn3 is welded, for example, to the inner side walls 48 of the outer metallic tank structure 46,715 ~ ~f~ 5 41. The upper dome portion 50 of the tank structure 41, extending down to the line "X-X", has a substantlally con-stant radlus of curvature "R" (Fig. 9~, and the terminal-bushing flange-rings 55 and 56 are welded thereto, so that the center-line "L" of the terminal-bushings 58, 59 is normal, or perpendicular to the curved upper surface of the dome 50. Thus, there is no necessity for accurate alignment of the termina.l-bushin~s 58, 59, inasmuch as regardless of their orientation, they nevertheless will be in the proper position, and the divergence angle " ~" between the two terminal-bushi.ngs 58, 59 will always be at the desired value.
The flexible connectors 60, 61, connected respec-tively to the upper sta.tionary contact structures 13, may be manually secured to the lower terminal-studs 66, 67 of the two terrninal-bushings 58, 59 by means of the manhole service opening 70 provided in the side wall of the tank structure 41. Thus, the major portion of the assembly operations may be conducted externally of the tank 41 with plenty of work-ing space. Following the subassembly, as mentioned, thetank 41 is dropped over the subassembly 1 to secure the two assemblies together. It will be noted that attached to the side of the metallic tank is the mechanism housing 75, together with its internally-located pneumatic mechanism 77.
Generally, this is of the type which, when operated, will ef~ect opening of the circuit-breaker 53. Thus, suitable ~alve structure 80 will adm~t high-pressure gas to a piston 81, which will effect downward movement of a piston-rod 82, consequent clockwise rotation of a bell-crank lever 83 having an arm 84, which is pivotally connected, as at 85, by 46,715 ~ 7 ~S

an operating link 86 tc a second bell-crank lever 87.
A second arm 89 of the second bell-crank lever 90 has pivotally connected thereto, as at 91, a connecting rod 92 having secured thereto a spring seat 93, which is biased toward the right, as viewed in Figure 1, in a direction to close the circuit-brealier 53.
The conllecting rod 92 is pivotally connected to the bell-cranlc l.ever assembly 95, which operates the main operating shaft 9. The construction is such that the com-pression spring ]00 effects closing of the circuit-inter-rupter 53, a closing shock-absorber 101 being provided to limit the closing travel. of the circuit-breaker 53.
During the opening operation, the valve mechanism 80 is actuated to effect, through the piston 81 and the a~oresaid interconnecting linkage, the downward opening movement of both movable contact structures 15 to the posi-tion illustrated in Figure 3.
Where the terminal-bushings 58 and 59 are not utilized for certain applications, the construction, as illustrated in Figure 6, may be employed, wherein the ter-minal rings 110, 111, affixed tc the flexible connectors 60, 61, may be fixedly secured to hollow conductors 115, which constitute a part of a gas-i.nsulated transmission system 116. A fragmentary portion of such a gas-insulated system 116 is illustrated in Figure 6.

To minimize the effect of eddy-current heating losses, and the consequent heating resulting therefrom, a non-magnetic insert-strip 120 (~ig. 9) may be utilized between the terminal~bushing mounting flange-rings 55, 56, as shown more clearly ln Figu.re 7 of the drawings. Fcr _g _ 46,715 ~t~`77~

uprating the continuous current-carrying capability of the clrcuit-breaker 53, the entire top upper dome portion 50 may be fabricated of a suitable non-magnetic material, such as stainless steel for example, as shown in Fig. 8. This, as mentioned, would include the dome portion extending down to the line "X-X" in Fig. 8.
By way of retrospect, the vertical tank cyllnder 41 provides the maximum gas volume, while minimizing the floor space required. The metallic tank 41 is, of course, at ground potential, and is pressurized, say at a pressure of 75 p.s.i.g. The structural support for the terminal-bushings 58, 59, current transformers 130, 131, mechanism and control housings 75 is all afforded by the said metallic grounded tank 41.
From the foregoing description, it will be appa-rent that there has been provided an improved circuit-breaker construction 53 capable of rapid assembly in dif-ferent assembly stages, enabling the outer tank structure 41 to be dropped over the interrupter assembly 1 and bolted onto the lower support plate 12.
The flush-mounted bushing entrance flanges 55, 56 greatly simplif~ the tank fabrication 41 as well as elimi-nate the need for stainless steel nozzles and special welding fixtures. The top dome, or head 50 on the tank 41 is made such that the entrance flange center-line "L" is normal to the tank dome surface, this takes advantage of the radius "R" (Fig. 9) of this head 50 to provide the required bushing angle "oC " of separation. Also, this design is readily uprated in continuous current by adding a very small 3o non-magnetic insert 120 (Fig. 7) between the two entrance 46,715 :l~rii~77":;;S

flanges 55~ 56. If necessary the entire top dome 50 may be fabricated from non-magnetic stainless steel as shown in Fig. 8 to substantially and economically increase the con-tinuous current rating.
A most important feature of the tank design 41 is its adaptability to gas-insulated breaker arrangements 116.
This is because of the compact geometry and versatile ent-rance flanges 55, 56.
Although there have been illustrated and described specific structures, it is to be clearly understood that the same were merely for the purpose of illustration, and that changes and modifications may readily be made therein by those skilled in the art, without departing from the spirit and scope of the invention.

Claims (7)

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

1. A method of fabricating a compressed-gas circuit-interrupter of the type involving two breaks and including an outer grounded metallic tank and a pair of terminal-bushings supported by the said grounded metallic tank, the method comprising constructing the interrupting components as a separate subassembly, securing the said subassembly to a metallic supporting plate, dropping the outer metallic tank over the said subassembly, and finally bolting the support plate to the lower portion of the outer-disposed metallic tank.

2. The method according to claim 1, including affixing a mechanism housing including an interiorly-located mechanism to a side-wall of the grounded metallic tank.

3. The method according to claim 1, comprising utilizing two gas modules, mechanical means for mechanically interconnecting the two gas modules together, a vertically-disposed main operating rod, and a supporting cylinder for supporting said two gas modules and also enclosing the main operating rod.

4. A method of fabricating a tank-type compressed-gas circuit-interrupter of the type including a pair of terminal-bushings extending into the said tank and inter-rupting means disposed within the tank and having a flexible connection to the said two terminal-bushings, said method comprising the steps of constructing said interrupting means as a separate subassembly divorced from the tank itself, and dropping the tank structure over the aforesaid subassembly for final assembly of the circuit-interrupter.

5. A method as claimed in claim 4, in which a pair of openings is formed at the upper end of said tank structure, a pair of flange rings being secured to said tank structure upper end adjacent said upper end openings, a pair of the terminal bushings being secured to the flange rings; and a non-magnetic insert interposed between the flange rings.

6. A method as claimed in claim 5, wherein the spherical top head of the tank structure 18 formed of a non-magnetic metallic material.

7. A method as claimed in claim 5, wherein the spherical top head of the tank structure 18 formed of stainless steel.