US3128360A

US3128360A - Interrupter structure having splitter plates of malleable material

Info

Publication number: US3128360A
Application number: US2390A
Authority: US
Inventors: Earl B Rietz
Original assignee: ITE Circuit Breaker Co
Current assignee: ABB Inc USA; ITE Circuit Breaker Co
Priority date: 1960-01-14
Filing date: 1960-01-14
Publication date: 1964-04-07
Anticipated expiration: 1981-04-07

Description

April 7, 1964 E. B. RlETz y 3,128,360

INTERRUPTER STRUCTURE HAVING SPLITTER PLATES OF' MALLEABLE MATERIAL Filed Jan. 14, 1960 4 Sheets-Sheet 1 Aprxl 7, 1964 E. B. Rlr-:Tz 3,128,360

INTERRUPTER STRUCTURE HAVING SPLITTER PLATES OF MALLEABLE MATERIAL Filed Jan. 14. 1960 4 Sheets-Sheet 2 EEN?.

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INVENTOR. ma a. ,e/frz BY sreaLg/ve, 51am?, 6242; JaFf-m April 7, 1964 RIETz 3,128,360

E. B. INTERRUPTER STRUCTURE HAVING SPLITTER PLATES OF MALLEABLE MATERIAL 4 Sheets---Sheelil 3 Filed Jan. 1.4. 1960 BY diria; au, Krane, rea (J5/ww April 7, 1964 E. B. RIETZ 3,128,350 INTERRUPTER STRUCTURE HAVING SPLITTER PLATES OF MALLEABLE MATERIAL Filed Jan. 14, 1960 4 Sheets-Sheet 4 I I l 84 LMA',

INVENTOR. EAI/QL /e/Ez /7 Trae/vf w United States Patent O 3,I28,36tb INIERRUPIER STRUCTURE HAVING SIILI'ITER PLATEE F MAIJIJEABLE MATERIAL Earl B. Rietz, Gilendaie, Caiii., assigner to I-T-E Circuit llrcaiter Company, Philadelphia, Pa., a corporation of Pennsylvania Filed Ilan. 14, 1960, Ser. No. 2,390 6 Claims. (Cl. Z60m-150) This invention relates to fluid blast circuit interrupters i for high speed circuit breakers, and more particularly relates to a novel interrupter assembly which uses a single pair of contacts.

The present invention is directed to an interrupter structure in which only a single pair of contacts are required for relatively high voltage ranges (of the order of -69 kilovolts) where the circuit being protected may be interrupted within a few half cycles.

In the preferred embodiment of the invention, the interruptor is formed of a stack or" bailes which are sectionalized into an upper and lower interruptor chamber by a division baie. A single arc generated by a single pair of contacts is drawn through a preferred portion of the interrupter structure which contains an upper chamber and a lower chamber. The upper chamber is especially adapted to promote rapid interruption of extremely large current arcs, while the lower chamber is especially adapted to promote the rapid interruption of medium current arcs.

. A further novel configuration is provided below the two aforementioned chambers which is particularly useful in the interruption of extremely small current arcs.

Accordingly, the primary object of the present invention is to provide a novel interrupter structure of the fluid blast type which will open high power circuits within a few half cycles.

Another object of this invention is to provide a novel interrupter structure of the single contact type.

A further object of the invention is to provide a novel high speed interrupter structure which reduces arcing time to reduce contact erosion and oil deterioration.

A further object or" this invention is to provide a novel interrupter structure wherein a high degree of control over the arc position and the pressure generated by the arc is obtained.

Another object of this invention is to provide a novel high speed interrupter wherein the arc splitters are relatively malleable whereby they will partially liow around the port openings to prevent communication between adjacent ports within the interrupter structure.

Yet another object of this invention is to provide a novel interrupter structure having an upper and lower chamber for high current and low current arc interruption respectively, with a still further chamber means below the two chambers for aiding in the interruption of eX- tremely small current arcs.

Another object of this invention is to provide a novel interrupter structure formed of a plurality of keyed baie plates to promote easy assembly of the interrupter.

A still further object of the invention is to provide a novel interrupter chamber construction wherein the entire chamber wall is made of a libreglass type material with an appropriate binder.

It is another object of this invention to provide a novel interrupter structure of a plurality of easily assembled keyed baffle parts which are secured by a single locking means. t

Yet another object of this invention is to provide a novel battle structure for oil blast circuit breakers where the bailles are formed of a non-tracking, non-gas evolving, arc quenching material having a polyethylene base which can be formed by injection molding techniques.

plee A still further object of this invention is to provide a novel interrupter for oil circuit breakers which is easily removable, and occupies a relatively small oil volume within the circuit breaker.

Another object of this invention is to provide a contact structure for high voltage interrupters wherein a stationary Contact is positioned off-center to insure that the arc will be drawn adjacent to the ports of the interrupter chamber.

These and other objects of this invention will become apparent from the following description when taken in connection with the drawings, in which:

FIGURE 1 shows a side cross-sectional view of an interrupter structure constructed in accordance with the present invention.

FIGURE 2 shows a partial side plane View of the interrupter of FIGURE 1 as seen from the left to particularly show the venting ports.

FIGURE 3 is a top plan view of the iirst plate of the arc interrupter assembly.

FIGURE 4 is a side plan View of the plate of FIG- URE 3.

FIGURE 5 is a top plan view of an arc splitter plate oi the assembly of FIGURE 1.

FIGURE 6 is a front plan view of the arc splitter plate of FIGURE 5.

FIGURE 7 is a top plan view of the division battle plate of FIGURE 1.

FIGURE 8 is a side plan View of the division baille of FIGURE 7.

FIGURE 9 is a top plan view of the lower battle plate of the interrupter of FIGURE l. v

FIGURE 10 is a side cross-sectional view of the plate of FIGURE 9 taken across lines 10-10 in FIGURE 9.

FIGURE 1l is an exploded perspective View of the interrupter of FIGURE l.

FIGURE l2 shows a top view of the retaining bushing.

FIGURE 13 is a side View of FIGURE 12.

FIGURE 14 is a bottom view of the interrupter chamber tube.

Referring now to the drawings and particularly to FIG- URES l and 1l, the interrupting unit shown is supported within an oil lled tank from a conductor stud or adapter Ztl which is adapted to connect to an inclined terminal bushing (not shown).

' A pressure conning tube 22 is then rigidly connected to conductor stud Ztl, as will be described later, and the wall of tube 22 is provided with a plurality of

ports

28, 30, 32, 34, 36 and 38 through which exhaust gases and oil are vented under pressure during arc interruption within the tube 22.

In the past, pressure confining tube 22 has been formed of a heavy walled paper tube. In accordance with the present invention, tube or chamber 22 is made of a breglass type material which can be made as strong as steel and as light as magnesium. Thus, the chamber 22 can be made of iibreglass having an epoxy or polyester resin binder.

The use of breglass further permits the incorporation of an upper internal thread 23 which threadably receives a clamp means to be described later and the conductor stud 20, as shown in FIGURE 1.

As an alternative, the tube 22 can have an intermediate casting of aluminum, for example, bonded thereto by a bonding means such as a bond formed of equal parts of Conley weld CI and C2 and the aluminum casting can then receive the stud 20. This type of structure is shown in my copending application Serial No. 2,530, filed January 14, 1960, now abandoned, and assigned to the assignee of the present invention.

The batlie stack within the interrupter is formed of a plurality of axially spaced bale members which are held in position with respect to one another by tubular spacing means. More specifically, the baille stack is formed of

baille members

40, 42, 44, 46, 48, 50, 52 and 54. All of baille members 40 through 54 have been previously made of a libre-type of material. This type material has the disadvantages of not being stable dirnensionally, requires machining to a proper contour, as it is not susceptible to molding. y

In accordance with the present invention, selected baille members may be made of materials other than fibre, such as a polyethylene base material which can be injection molded, and is characterized in being non-tracking, non-gas evolving, and arc quenching type material.

Referring more specifically to the baille elements, baffle member 40 is shown in FIGURES 3 and 4 as comprising a disk which may be of a fibre material and has a keyshaped opening 56 therein for receiving the movable contact element of the interrupter and one of the stationary contact elements, as will be described hereinafter. Baille member 40 is further provided Vwith a keying notch S8 which receives a cooperating protrusion of the next lower baille in order to hold the two members in alignment with respect to one another to insure proper alignment during assembly. l

A ilbre spacing tube 60, best seen in FIGURES 1 and ll, is then positioned within container 22 and above baille 40, and has its upper end abutting against a locking ring 62 which is threadably carried by threads 23 of container 22. Thus, the locking ring 62, as will be hereinafter seen, may be tightened downwardly against spacer 60 after the complete baille assembly is connected together to rigidly retain the baille assembly in position.

Immediately below baille 48 is a ilrst splitter plate 42, best seen in FIGURES 5 and 6. As shown in FIGURE l1, the

splitter plates

42 and 44 are contained within tubular spacer segment 64 which also abuts the upper baille plate 40 and the lower baille plate 46.

Splitter plates

42 and 44 are provided with upper and lower keying projections and depressions respectively, such as projection 66 and depression 68, as well as semicircular projection 70 (see projection 70 of plate 42 in FIGURE 11). The projection such as projection 78 of FIGURES 6 and 11 for plate 42 is keyed to depression 58 of upper plate 48 of FIGURE 3 so that these elements are easily aligned with respect to one another within container 22.

In a like manner, the

splitter plates

42 and 44 are aligned with respect to one another by their cooperating projections and

depressions

66 and 68, shown in FIG- URE 6.

While the splitter plates could be made of libre, their complex shape would dictate complex and expensive fabrication. Moreover, it is important that the splitter plates be of a material that will not carbonize, is nontracking and non-gas evolving.

In accordance with the present invention, the splitter plates such as

plates

42 and 44 may be made of a nontracking, non-gas evolving material having a polyethylene resin base, and is capable of fabrication by injection molding. By way of example, a material having a composition of 100 parts by weight of a polyethylene resin, 1 to 2 parts by weight of carbon-black, Vand 70 parts by weight of talcum has been found to give good results. In addition, this material is slightly malleable, the importance of which will be described hereinafter.

Next below the splitter plate 48 is a division baille 46 of fibre material shown in FIGURES 7 and 8 as having two keying Vdepressions 74 and 76. For relatively high ratings, baille 46 is made of a iibreglass material for added strength since it is subjected to very high pressures. The division baille 46, as will be seen hereinafter, creates an upper chamber 79 and a lower chamber 81, as shown in FIGURE l. Division bailleV 46 is keyed with respect to lower splitter plate 44 by means of a projection, such as projection 70 of FIGURE 6, which is keyed into depression 76 of division baille 46.

Splitter plates

48 and 50 which lie below division baille 46 are constructed in a manner identical to that of

plates

42 and 44 and are keyed with respect to one another and with respect to division baille 46 in an identical manner.

The

splitter plates

42, 44, 48 and 50 are, as stated above, identical in construction. Therefore, these plates are interchangeable with one another, and an increased number of exhaust ports can be formed by merely adding further splitter plates in the stacks.

Immediately below splitter plate 50 is the plate 52 which may be molded of a phenolic resin material. If desired, plate 52 may be made of a polyester glass compound to improve non-tracking and non-arcing characteristics. Plate 52, as shown in FIGURES 9 and 10, has

a keying depression 78 and a centrally aligned apertureV 88. One side of the plate 52 is provided with a hollow section 82 which forms an auxiliary chamber with respect to the adjacent plate 54 which, as shown in FIGURE 1, is identical to plate 54.

Plates

52 and 54 are keyed with respect to one another, even though they are symmetric to permit alignment of the port openings of the stack during assembly. Thus, plate 52 may have a keying projection 83V which cooperates with a depression of plate 54, similar to depression 78 of plate 52, as shown in FIG- URES 9 and l0.

It will be noted that two auxiliary chambers or oil receiving pockets are created between

members

54 and 84, these chambers being chambers and 92, respectively.

The final member of the baille stack is a ilxed throat bushing or retaining bushing 84 which may be secured to the bottom of container 22 by screws, dowel pins, adhesives, or other fastening means which communicate between tube 22 and bushing 84. Y

Throat bushing 84 is preferably of a phenolic resin material and serves the dual function of being the lower bushing and of Vsupporting the baille stack in tube 22 and prevents it from being blown out the bottom of tube 22. Throat bushing 84 may also be molded of a polyester glass compound to improve non-tracking and non-arcing characteristics. It is also possible, if desired, to wind throat bushing 84 into the ilbreglass chamber 22 to make it an integral part of the assembly. The bottom of tube 22 isl formed with an inner shoulder 85 which receives the enlarged upper portion of throat bushing 84 as shown in FIGURE 1. Throat bushing 84 which is best seen in FIGURES l2 and 13 has a central opening 86 which receives the movable contact with close clearance, as will be described more fully hereinafter. A keying depression 87 of bushing 84 cooperates with a protrusion of baille member 54 so that the baille stack is keyed in position with respect to bushing 84. The bushing is then keyed to tube 22 by means of a key slot 87 in the wall of bushing 84 which cooperates with a rib 88 (FIGURES 1 and 14) which is integral with tube 22. Accordingly, the baille stack port openings will be properly aligned with the openings in the tube 22.

The assembly of the interrupter is apparent whereby the throat bushing 84 may be secured in keyed alignment in chamber 22 and the remaining baille plates are then subassembled and pushed into place. The baille assembly is then held in position by the clamping ring 62 which is threaded into thread 23 of tube 22 to apply pressure to the baille assembly.

A movable contact rod 94 having an arc resistant material tip extends upwardly through the bottom of the baille structure and toward a movable contact structure generally seen at 96 at the top of the interrupter structure. More speciilcally, the stationary contact structure is carried from, and is electrically connected to, adapter 20, and is comprised of a plurality of angularly disposed contacts, such as contact 98 of FIGURES 1 and 1l which form `a tulip-type cluster of contacts. Contact 98 is typical of the eight current carrying contacts and is supported from an electrically conductive hollow hub 100 by a flexible conductive strap 102 which is backed up by a high pressure leaf spring 104 which engages an insulating button 106 carried from stationary contact 98. It will be noted that the insulating button 106 prevents current from iiowing through the biasing spring 104, and confines it entirely to conductor 102 so that the spring will not be heated by current iiow which could cause a change in the spring characteristic. Since each of the contacts is provided with its individual biasing spring, even contact pressure is assured.

If desired, the biasing springs for the stationary contacts could be provided by individual compression springs carried by a spring cage which surrounds the contact cluster. Here again the springs should be isolated from the current path. Furthermore, metal spacers (not shown) may be provided between fingers to prevent their being drawn together and welded under short circuit current conditions.

An arcing contact or arc positioning finger 108 which differs from the other stationary contacts in being longer and being (tipped) of an arc resistant material is provided to partially extend into the elongated portion 110 of opening S6 of plate 40, as shown in FIGURE 3.

The operating structure for contact 94 is not shown herein, but may be of any desirable type, and operates to withdraw the contact 94 (which is in the engaged position in FIGURE 1) downwardly and out of the stack of baffles to a position external ofthe interrupting chamber. Since the arc is most vulnerable when displaced sidewise and toward the exhaust ports through 38, the arc is encouraged, from its inception, to assume this favorable displaced position because of the extended arcing contact 108 which is positioned along the side of the interrupting chamber 22 which contains these ports. Thus, the arc is drawn from the arcingrnger or contact 108 for immediate displacement toward the exhaust ports to obtain instant blasting and pressure relief through the exhaust ports. During arcing, it will be noted that baffle plate 40 shields the end of the stationary contact fingers such as finger 98 to protect them from the arc.

The use of the division barrier 46 between chambers 79 and S1 inherently improves creepage path conditions, and functions to afford multiple arc extinguishing systems arranged closely in series which, namely, are the separated interrupting chambers '79 and 81.

Thus, for very heavy current interruption, intense pressure is generated from the inception of the arc, which pressure will immediately relieve itself through the

upper exhaust ports

28, 30 and 36 in upper chamber 79 so that the arc will blast itself explosively to the left While the

lower openings

34, 36 and 38 are still substantially closed off by the contact rod which is, although moving downwardly, still covering these port areas. It is to be noted that the center of rod 94 may have an axial opening therein for venting off excessive pressure developed during high arc current conditions.

In the event that the arc is a medium or low current arc, lower pressures are generated, and the arc will continue to be drawn downwardly into the lower chamber 81 where it will then be subjected to cross blast action from the fluid displaced from the upper chambers, as well as from the fluid contained in chamber 8l.

In the past, and in the event that a very light current arc is drawn, insufiicient pressure is developed in the chamber 81 to provide blast action, and the arc may continue after the end of contact 94 leaves the lower ba'le plate 52. In the novel sub-chamber arrangement, however, when the arc reaches the sub-chambers 90 and 92 between the baile stack and the throat bushing 84, some pressure will be generated in the sub-chambers 90 and 92 to produce a flow of fluid upwardly through the central opening and toward the exhaust ports. More important than this, however, the arc is exposed to the additional oil in the lower pockets whereby additional cooling of the arc results to aid in its interruption. By the time, then, that the tip of contact rod 94 leaves the interrupter, the circuit will be interrupted, regardless of whether the fault current is of an exceptionally heavy magnitude or an exceptionally small magnitude.

It will be noted that

chambers

79 and 81 form relatively large oil reservoirs to provide space for the formation of a gas bubble during interruption and to supply oil to the volume evacuated by the contact rod 94. This is of great importance where the interrupter is for reclosing and a second interruption may occur immediately after the first.

As previously stated, the arc splitter plates are preferably of a material which is slightly malleable. This feature will cause the plates to flow around the lips of the port openings whereby the adjacent port openings are positively isolated from one another Within the interrupter chamber and the possibility of arc gas seeping between the casing 22 and arc splitter to cause communication between two ports is prevented.

Although this invention has been described with respect to its preferred embodiments, it should be understood that many variations and modifications will now be obvious to those skilled in the art, and it is preferred, therefore, that the scope of this invention be limited not by the specic disclosure herein but only by the appended claims.

What is claimed is:

l. A container for an interrupter; said container being an elongated cylinder having a plurality of venting ports in the wall thereof; said container being comprised of a fibreglass material having a polyester resin binder; said container having a plurality of integral threads at one end thereof for receiving a clamping means, and a restricted internal section at its other end for receiving a throat bushing means inserted from said one end of said container; said clamping means being operable to clamp a stack of baliie plates against said throat bushing means within said container.

2. In an interrupting chamber for an oil blast circuit breaker; a hollow cylindrical container having a venting port therein and a first and second arc splitter plate; said first and second arc splitter plate being disposed adjacent one another and being supported with respect to said container; said rst and second arc splitter plate having a configuration dening a channel from an internal portion of said container to said venting port; edge portions of said first and second arc splitter plates being positioned adjacent the top and bottom respectively of said venting port; said first and second arc splitter plates being of identical construction and being interchangeable with respect to one another; said first and second arc splitter plates being of a malleable material whereby said edge portions of said first and second arc splitter plates will flow over the upper and lower portions of said venting port to seal the engagement between said first and second arc splitter plates and the container portion carrying said venting port.

3. In an interrupting chamber for an oil blast circuit breaker; a hollow cylindrical container having a venting port therein and a first and second arc splitter plate; said first and second arc splitter plate being disposed adjacent one another and being supported with respect to said container; said first and second arc splitter plate having a configuration deiining a channel from an internal portion of said container to said venting port; edge portions of said first and second arc splitter plates being positioned adjacent the top and bottom respectively of said venting port; said first and second arc splitter plates being of identical construction and being interchangeable with respect to one another; said arc splitter plates being molded of a non-tracking, non-gas evolving material having a polyethylene base; said first and second arc splitter plates being of a malleable material whereby said edge portions of said first and second arc splitter plates will flow over the upper and lower portions of said venting port to seal the engagement between said first and second arc splitter plates and the container portion carrying said venting port.

4. In an interrupting chamber for an oil blast circuit breaker; a hollow cylindrical container having a first and second venting port therein and a first, second and third arc splitter plate disposed in a stack and supported with respect to said container; said first, second and third arc splitter plates being identical in construction and being interchangeable with respect to one another; said first and second arc splitter plate defining a first channel which communicates from an internal portion of said container to said first port; said second and third arc splitter plate defining a second channel which communicates from an internal portion of said container to said second port; edge portions of said first and second arc splitter plates being positioned adjacent the top and bottom respectively of said first port; edge portions of said second and third arc splitter plates being positioned adjacent the top and bottom respectively of said second port; said first and second and third arc splitter plates being of malleable material whereby said edge portions of said plates will flow around the edges of their respective ports to thereby seal off possible communication between said first and second ports between the inner Wall of said container and said second arc splitter plate.

5. The device substantially as set forth in claim 2 which further includes a stationary contact and a movable bayonet type contact movable between an engaged and disengaged position with respect to said stationary contact; saidv stationary contact being positioned within said interrupter chamber; said stationary contact including a contact finger, leaf spring biasing means for biasing said contact finger toward engagement with respect to said movable contact rod, a contact hub and flexible connecting means; said contact hub being electrically connected to said contact finger by said flexible connecting means; one end of said leaf spring biasing means being connected to said contact hub, the other end of said leaf spring biasing means engaging said contact finger; said contact finger having an insulated button extending therefrom; said leaf spring engaging said insulating button.

6. The device substantially as set forth in claim 2, wherein said first and second arc splitter plates have a crescent-like shape with said edge portions being centrally of the circular portion of said crescent and forming an oil receiving pocket at the cut-away portion defining said crescent.

References Cited in the file of this patent UNITED STATES PATENTS 1,673,676 Hilliard June 12, 1928 1,762,604 Ainsworth June 10, 1930 1,981,404 Whitney et al Nov. 20, 1934 2,036,800 Ehrenberg et al Apr. 7, 1936 2,095,729 Beirsdorf Oct. 12, 1937 2,328,825 McMahon Sept. 7, 1943 2,467,542 Taylor Apr. 19, 1949 2,531,007 Strom et al Nov. 21, 1950 2,647,973 Umphrey Aug. 4, 1953 2,714,645 Salzer Aug. 2, 1955 V2,717,294 Balentine Sept. 6, 1955 2,733,322 Curtis Jan. 31, 1956 2,833,890 Jacobs May 6, 1958 2,870,295 Haroldson et al Jan. 20, 1959 2,874,338 Pease Feb. 17, 1959 2,924,690 Brown et al Feb. 9, 1960 FOREIGN PATENTS 450,405 Great Britain July 16, 1936 510,030 Great Britain July 26, 1939 521,861 Great Britain June 3, 1940 561,395 Belgium Oct. 31, 1957 1,203,659 France Aug. 3, 1959

Claims

2. IN AN INTERRUPTING CHAMBER FOR AN OIL BLAST CIRCUIT BREAKER; A HOLLOW CYLINDRICAL CONTAINER HAVING A VENTING PORT THEREIN AND A FIRST AND SECOND ARC SPLITTER PLATE; SAID FIRST AND SECOND ARC SPLITTER PLATE BEING DISPOSED ADJACENT ONE ANOTHER AND BEING SUPPORTED WITH RESPECT TO SAID CONTAINER; SAID FIRST AND SECOND ARC SPLITTER PLATE HAVING A CONFIGURATION DEFINING A CHANNEL FROM AN INTERNAL PORTION OF SAID CONTAINER TO SAID VENTING PORT; EDGE PORTIONS OF SAID FIRST AND SECOND ARC SPLITTER PLATES BEING POSITIONED ADJACENT THE TOP AND BOTTOM RESPECTIVELY OF SAID VENTING PORT; SAID FIRST AND SECOND ARC SPLITTER PLATES BEING OF IDENTICAL CONSTRUCTION AND BEING INTERCHANGEABLE WITH RESPECT TO ONE ANOTHER; SAID FIRST AND SECOND ARC SPLITTER PLATES BEING OF A MALLEABLE MATERIAL WHEREBY SAID EDGE PORTIONS OF SAID FIRST AND SECOND ARC SPLITTER PLATES WILL FLOW OVER THE UPPER AND LOWER PORTIONS OF SAID VENTING PORT TO SEAL THE ENGAGEMENT BETWEEN SAID FIRST AND SECOND ARC SPLITTER PLATES AND THE CONTAINER PORTION CARRYING SAID VENTING PORT.