Патент USA US2412919код для вставки
Dec. 17, 1945. ` J. SLEPIAN ~ 2,412,919 cIRcUIT-INTERRUPTER Filed March 27, 1943 2 vSheets-Shea?. l fill \ \ _' " A . l 7 . ¿El -INVENTOR Josep/2 S/@p/'a/Z .IW/Q. W Patented Dec. 17, 1946 2,412,919 UNITED STATES PATENT GFFICE 2,412,919 CIRCUIT INTERRUPTER Joseph Slepian, Pittsburgh, Pa., assigner to West inghouse Electric Corporation, East Pittsburgh, Pa., a corporation of Pennsylvania 1 > Application March 27, 1943, serial »10.480.733 1o claims. (o1. zoo-_148) 2 This invention relates to circuit interrupters ' in general, and, more particularly, to circuit in terrupters of the type which utilize an aro ex tinguishing gas to effect-turbulence within the Fig. 4 is an enlarged fragmentary plan view of the top fixed electrode looking down on the line IV-IV of Fig. 2; ' Fig. 5 is an elevational View, partly in section, arcing region to assist in extinguishing the arc 5 of a circuit interrupter embodying a modiñcation drawn during a circuit interrupter opening of my invention; ' operation. Fig. 6 is an inverted View in section taken on An object of my invention is to provide an improved circuit interrupter having cooperable line VI--VI of Fig. 5; and f Fig. 7 is an inverted View in section taken on electrodes, in at least one of which are disposed 10 the line vri-vir of Fig. 5. a plurality of gas conducting apertures. Referring to the drawings, and more particu Another object is to provide an improved cir cuit interrupter which' sends a plurality of gas jets at substantially acoustic velocity into the arcing region. A further object is to provide 'an improved circuit interrupter which has cooperable perfo .larly to Fig. 2, the reference numeral I designates a fixed plate electrode to which a terminal 2 is rigidly attached. The fixed plate electrode I has 15 Y'formed therein a plurality- of exit apertures 3 inclined helically as more clearly shown in Figs. 3 and 4. rated electrodes, and to send a plurality of gas Cooperating with the ñxed plate electrode I is jets at near acoustic velocity through the perfo 4Va second fixed plate electrode 4 which has a con ratlons or apertures in one electrode into the 20 tact portion 5, and which has a terminal 6 rigidly arcing region and out the perforations yor aper connected thereto. The fixed plate electrode 4 tures in the other cooperable electrode also at has'formed therein a plurality of inlet apertures near acoustic velocity to effect rapid extinction 'I inclined helically as more clearly shown in Fig. of the arc drawn between the electrodes. 3. _It Will be observed that the exit apertures 3, Another object is to provide an improved cir 25 provided in the fixed plate electrode I, are in cuit interrupter having at least one gas conduct clined helically in an opposite direction from the ing pa-ssage through one electrode to' not only direction of the helically inclined inlet apertures effect turbulence in the arcing region but also to ‘I formed in the ñxed plate electrode 4, as more Aeffect a lateral movement of the arc to distribute clearly shown inr Fig. 3, the purpose for which the heating effect of the terminal of the arc over 30 will appear more clearly hereinafter. the surface of the electrode. ` ’ A more speciiic object is to provide an improved -circuit interrupter comprising a pair or cooper' Disposed between lthe- fixed plate electrodes I, 4 and maintaining `them‘in spaced relation is an "insulating ring 8', more clearly shown in Fig. 2. -able electrodes between which :an arc-may be Also disposed between' the plate electrode I, 4 is established, and to provide gas conducting aper 35 an insulating plate 9'. v¿'I‘hreadedly secured to the tures in both electrodes inclined helically in op `iixed plate electrode 4 ist an insulating tubular , posite directions to effect both turbulence and ñared conduit member I0, which serves to 'con lateral arc movement in the arcing'reg'ion be =duct a suitable arc extinguishing gas, in this in tween the electrodes. ‘ ' ' ~stance compressed air, toward the inlet apertures Another object is to provide an annular arcing 40 "I' disposed in the fixed plate electrode 4, as shown Vpassage between two cooperable electrodes in more clearly by the arrows in Fig. 2. which the established arc may be moved laterally. The fixed plate electrode | has an upstanding For purposes of illustration I describe my in guide portion II which serves to guide a movable vention as applied to circuit interrupters of the ltubular conducting bridging electrode I 2. In the 'compressed air type. Other gases such as carbon 45 closed circuit position of the interruptor the dioxide, hydrogen, etc., may, however, be used. movable tubular bridging electrode I 2 engages the . .Further objects and advantages oi my inven lContact portion 5 of the fixed plate electrode 4 'tion' will readily become- apparent upon a reading toelectrically connect the plate electrodes I, 4. ofthe following specification taken in conjunc r‘Consequently,.the electrical ycircuit through the »tion withi the drawings, in which: ' 50 vinterrupter >in the ‘closed circuit position (not _ Figure 1` is a plan view of a circuit interruptor l“slîiowrn comprises the terminal 2, the fixed plate embodying my invention; ` ’ ' Fig. 2 isa -view in cross section taken on the line II--II of Fig. 1; electrode l, the' movable tubular' bridging elec trode> I2 ; Contact portion 5 of 'fixed plate electrode 4 to the other terminal `6 of. the interruptor." ’ = Fig. 3 'is a view in cross section taken on the, 55 Exit apertures '3"a1'e' also provided in the mov line vIII-III-‘oi' Fig. 2; ' 1 able tubular electrode I2 and also in the upstand 2,412,919 3 d ing guide portion II, as more clearly shown in Fig. 2. It is, therefore, desirable to prevent a rotation of the movable tubular bridging elec trode I2 with respect to the fixed plate electrode I. The key I3, rigidly secured to the electrode I2 sliding in the longitudinal 'recess I4 provided in the upstanding lguide portion II, prevents rota The arc I 6 is carried rapidly around the an nular arcing passage I 5 at high velocity and per mitted to play between the annular portions of the electrode plates I and ß relatively unimpeded and unrestricted. At a current zero the arc will not restrike because of the increase in dielectric strength of the air within the rannular interelec trode arcing passage I5 caused by the turbulence tion of the bridging electrode I2 with respect to of the air jets passing through the inlet aper the plate electrode I. Referring to Figure 2 it will be observed that ’ tures 7 in plate electrode 4 at substantially acous the insulating ring 8 cooperates with the insu tic velocity. Also the rotation of the arc I5 lating plate 9 to form an annular interelectrode around the annular arcing passage I5 distributes arcing passage generally designated by the refer the heating effect over the extended surfaces of he electrodes I, 6 to minimize the emission cf ence numeral I5 the ends of which are bounded ionized metallic particles from the plate elec by annular arcing members formed by the in trodes I, ll. rl‘he .arc I 6 is extinguished-at the wardly exposed surfaces of electrodes I and 4 respectively. The edge portions of the insulating first current Zero, and suitable means not shown ring 8 and insulating plate 9 adjacent the arcing may then stop the compressed air ñow. passage I5 have apertures formed therein to align In the embodiment of my invention shown in Figs. 5 through '7 inclusive there is provided a with the apertures 3, 'I of plate electrodes I, 4 as more clearly shown in Fig. 2. Positioning pins fixed tubular electrode 2l having a plurality of inlet apertures 22 preferably generally uniformly I8, as more clearly shown in Fig. 2, prevent rota~ tion of the insulating plate 9A with respect to the distributed across the face thereof. An insulat ing gas conduit 23 is threadedly secured to the _fixed plate electrode 4. During the opening operation of the interrupter fixed tubular electrode 2 I, and the passage of gas therethrough is controlled by the electrically ac the movable tubular electrode I2 is moved up tuated valve generally designated by the refer wardly by any suitable means to separate from the portion 5 of fixed plate electrode 4 to estab ence numeral 2d. Surrounding the tubular electrode 2I is an in lish an arc designated'by Vthe-reference numeral I6 in Fig. 2. The arc extinguishing gas, in this 30 sulating casing 25, in this instance cylindrical, instance compressed air, forced upwardly through which also serves as a guide for a movable tubu the tubular dared conduit II! passes through the helically inclined inlet apertures 'I of ñxed plate _ electrode 4 to result in a plurality of air jets lar electrode 26. Terminal k2'I is rigidly secured to the fixed tubular electrode 2l, and a terminal 23 is rigidly secured to the movable tubular elec trode 2’5 as 'more clearly shown in Fig. 5. Consequently in the closed circuit >positicnof the interrupter (not shown) the electrical circuit therethrough comprises terminal 28., movable tu bular electrode 2S, ñxed tubular electrode 2I, to terminal 21. Disposed in the movable tubular electrode 25 are a plurality of exit apertures 29 also preferably generally uniformly distributed across the face thereof. The reference numeral 30 generally des ignates the interelectrode arcing region. During the opening operation of the inter rupter shown in Fig. 5 the movable tubular elec. trode 25 is moved upwardly to separate` from the which enter the annular interelectrode arcing . passage I5 turbulently. The air flow through the inlet apertures ‘I produces not only a very high turbulence in the annular passage I5, but also produces an _angular momentum which causes a mass circulation of the air around the annular f interelectrode arcing passage I5 at high Velocity. The angular momentum carries the arc IB, which is initially established, rapidly around the an nular arcing passage I5 on the extended surfaces of the plate electrodes,A I, 4.Y Fig. 3 shows the position of the arc I6 after it has been carried part way around the annular arcing passage I5 to a position designated by the reference nu _meral I'I. I have found that for a circuit interrupter of the type shown in Figs. l-4 inclusive which is designed for 15,000 volts, 60 cycles, and large cur rents, thatA the pressure at the entrance. to the linlet apertures 'I in ñxed plate- 4 may be substan-- fixedv tubular electrode. 2I to draw an arc 3l >in V the interelectrode arcing region 30 and which is permitted to play relatively` unimpeded and un~ restricted between the electrodes 2l and 25 now serving as arc terminal members. Simultaneous ly, a suitable means (not shown) operates the tially 60 pounds per square inch absolute pres- 7“ electrically actuated' valve 25 to force a stream sure. The total area of the inlet apertures ‘I of gas, in this instance compressed air. upwardly is approximately 1115 of the eiîective> area of the fixed plate electrode 4. The interelectrode pres sure within the annular arcing passage I5 may be 30 pounds per square inch absolute pressure. ‘T1 Consequently the air jets coming into the annu lar arcing passage I5 through the inlet apertures 'I in fixed plate electrode 4 will have substantially the velocity of sound-in air, that is 14,000 inches: Der second. Y through the insulating conduit 23 and upwardly through the inlet apertures 22 into the arcing region 30. ~. / The compressed air jets passing through the ñxed tubular electrode 2l produce turbulence within the interelectrode arcing region 30 to ex tinguish the arc 3l at the first current zero. The direction of the compressed airV ilow is indicated by the arrows in Fig. 5. . , The total area of the exit apertures 3 in fixed For a circuit interrupter of the type shown in plate electrode I is substantially Tis of the eifec tive area of fixed plate electrode I. Atmospheric Fig. 5 designed for 15,000 volts, v60 cycles, and for high current, the separation between the fixed electrode 2l and the movable electrode 26 may be pressure, that is 15 pounds per square inch abso- ' lute pressure, prevails outside of the ñxed plate TI) taken as l centimeter at arc extinction. The electrode I. Consequently the air jets which pass transient peak voltage which the arcing'region through the exit apertures '3 in ñxed plate elec 20 must stand after current zero will be under-50 trode I will have substantially lthe velocityv of ` kv. This dielectric strength can be insured by providing that the compressed air in this space sound in air. The width between the plate elet»4 is at 30 pounds per square inch absolutelpres' trodes I. 4 may be approximately ‘f’a inch. 2,412,919 6 sure. After the transient it may fall to normal 15 `pounds per square inch absolute pressure. Compressed air is injected into the arcing re gion 30 at about acoustic velocity or 14,000 inches per second through the inlet apertures 22 in the fixed electrode 2| . The driving pressure is then 60 pounds per square inch absolute. The area of the apertures 22 may be substantially il@ the bodiments shown in the drawings the ratio is 1:2 which gives the best results. The pressure of the gas on the low pressure side of any of the electrodes I, 4, 2l, 26 should be from 1A to 3A, of the gas pressure on the high pressure side of the particular electrode. The preferred pressure is from 1)/8 to 578 of that on the high pressure side of the electrode. In the area of the ñxed electrode 2l. The area of the exit apertures 29 in movable electrode 20 may be substantially 1%; of the electrode area. There fore, the 30 pounds per square inch interelec trode pressure will discharge the air out through the exit apertures 2S in the movable electrode two breakers shown, the pressure on the low pressure side of any of the electrodes is 1/2 that on the high pressure side. This I have found to give the best results. Although I have shown and described specific structures it is to be clearly understood that the 26 at substantially acoustic velocity to atmos l5 same were merely for purposes of illustration, pheric pressure. and that changes and modifications may readily The air between the electrodes 2l, 26 will be be made by those skilled in the art without de in a highly turbulent state. The intensity fac parting from the spirit and scope of the inven tion. ` L' tor of the turbulence will be close to acoustic velocity, or 3.104 cm./sec. The scale factor of 20 I claim as my invention: ' the turbulence will be about 0.5 cm. The eiîec l. In a circuit interrupter, a pair of relatively tive diffusion coefficient due to this turbulence movable electrodes between which an arc is es will be of the order of the product of these fac tablished, means forming an annular arcing pas tors or about 104. sage disposed between the electrodes, an annular The time constant for the decay of ionization 25 arcing member disposed at each end of said arc and temperature in the interelectrode space will ing passage and between which said arc is adapt be ed to be moved relatively unimpeded and unre stricted, said arcing members having a plurality d2 of gas conducting apertures formed therein, and ä 30 means forcing gas under pressure at high velocity where d is the interelectrode separation and D is the effective diffusion coefficient. Taking d=1 and D=104, this gives a time constant of 10 mi unidirectionally through said apertures and said. arcing passage to create a highly turbulent at mosphere therein for extinguishing the arc. 2. In a circuit interrupter, a pair of electrodes croseconds, which is fast enough to ensure arc 35 between which an arc is established, at least one extinction in any practical circuit. of the electrodes having a plurality of gas con Figs. 6 and 7 show a comparison of aperture ducting aperturesformed therein which are in areas provided in the electrodes 2|, 26. clined helically. Although I have shown an application of my 3. In a circuit interrupter, a pair of cooperable invention to two different types of circuit inter 40 electrodes between which an arc may be estab rupters operating at 15,000 volts, 60 cycles, and lished, both electrodes having formed therein a at high currents it is to be clearly understood that plurality of gas conducting apertures, the aper for higher or lower voltage ratings or currents tures in the pair of electrodes being inclined hel the dimensions and also the pressure of the gas ically in opposite directions. used would necessarily be varied to suit the oper 4. In a circuit interrupter, a pair of cooperable ating conditions desired. eiectrodes between which an arc may be estab It will also be apparent that in both embodi lished, at least one electrode being substantially ments of my invention shown and described, the compressed air is injected in the form of a plu rality of air jets at acoustic velocity into the .~ arcing region, and is also exhausted out of the arcing region at acoustic velocity. Using com pressed air as the arc extinguishing gas, the ve locity of the air jets entering and leaving the arcing region should be in the range from 5,000 fiat and having one gas conducting aperture therein which is inclined with respect to the lon gitudinal axis of the electrode. 5. In a circuit interrupter, a relatively fixed tubular electrode closed at one end except for a plurality of apertures disposed therein, a oo operable movable tubular electrode also closed at “ one end except for a plurality of apertures dis inches per second to 14,000 inches per second, the latter figure being the numerical value of acous posed therein, a relatively tight fitting insulating tic velocity in air. My preferred range of veloc ities is, however, from 10,000 inches per second to 14,000 inches per second using compressed air. serving as a guide for the movable electrode and For other gases the numerical value of the Ve locity of sound is different from that in air. In hydrogen, for example, the velocity of sound is approximately four times that for air. Using other gases than air, the range of ve locities of the jets entering and leaving the arc ing region should be between 30% and 100% of casing surrounding the fixed electrode and also forming> an arcing region between the apertured surfaces of said electrodes, and means for forcing gas through the apertures in the fixed electrode into the arcing region and out through the aper tures in the movable electrode at a rate to create within the arcing region a turbulent atmosphere having a high coeflicient of diffusion to quickly extinguish the arc drawn between the electrodes. 6. In a circuit interrupter, a pair of electrodes the velocity of sound in the gas used. The pre between which an arc is established, means form ferred range is from '70% to 100% of the velocity ing an annular arcing passage disposed between of sound in the gas used. 70 the electrodes, at least one of the electrodes hav I have found that the ratio of the total inlet ing a plurality of gas conducting apertures formed aperture area in the inlet electrode to the total therein which are inclined helically. exit aperture area in the exit electrode should be '7. In a circuit interrupter, a pair of electrodes in the range from 1:1 to 1:3. My preferred between which an arc is established, means form "il ing an annular arcing passage disposed between range is between 1:11A to 1:21/2. In both em v'.aeraa-le .theelectrodes,A both the electrodes having‘a'íplu .plurality _of -gas exhaust :openings therethrough, rality of gas conducting apertures ¿formed there in `Which îare inclined ¿helically in A,opposite direc tions. means ¿for establishing `an '.arc. between said arc terminal members, and means for causing fa y'high vVelocity ‘blast of gas `to flow longitudinally , i8.. Ina circuit‘interruptenmeans of insulating Ci through said tubular vmember, said'inlet openings material 'deñn‘ing `'the iside walls :of an arc cham insaid one arc terminal member causing aïhig-h ber, a pair of arc terminal members disposed >in degree of turbulence in said arc -chamber, said spaced relation Y'and >arranged >.with respect to said exhaust openings in said other arc «terminal mem 'means of ¿insulating .material to enclose the op .posecl ends of `saidarc chamber, means for estab r:lishing an arc between said .aro .terminal mem bers, one of said arc terminal members having a vplurality of .generally uniformly distributed gas inlet rpassages therethrough, :means ier imoying .arc extinguishing gas fat .high velocity Vthrough - said inlet ‘passages :to `crea-gte .a highly turbulent atmosphere Within said chamber, .said other arc terminal member ~'having .a plurality >of generally uniformly distributed gas exhaust passages there through the total cross-,sectional area vof ‘which y is .such to' enable ysaid gas to exhaust from said chamber lat a vvelocity substantially equal to the inlet velocity -to enhance the turbulence -within 'the are chamber and bring .about a rapid ,diffu v»sion of Aions .and .quickly extinguish >the arc. '_9. In a circuit interrupter, a tubular member of insulating material, a pair of arc terminal members .of conducting material adapted to -be .positioned in .spaced relation within said tubular member .to provide rend walls of an arcing cham ber being so -proportioned `with respect ,to :said li) inlet openings to .cause said gas to exhaust :there through at substantially` the same Velocity ras .the gas entering lsaid chamber to .enhance the tur bulent effect 'in .the :arc chamber to quickly de ionize and extinguish the arc :and »to maintain the gas :therein -at a predetermined pressure. 10. In a circuit interrupter of the compressed gas type, a .pair of spaced >generally iiiat `arcter minal members between which `an arc is adapted to play, tubular tmeans rof insulating material ex tending 'between said arc terminal members Lto dei-lne .therewith an .arc chamber, `said arc ter minal :members having `a .plurality of apertures therein to permit va unidirectional flow of >gas through said arc chamber, means forestablishing an .arc .between >said farc terminal members, and means :for moving gas‘under suiiicient pressure ‘to produce a iiow through said apertures of the order of 30% to 100% acoustic velocity, said apertures fber, one of said arc terminal members having a being so arranged to ¿produce within said arc chamber a highly turbulent atmosphere having a high effective diñusion coeñ‘ìcient to quicklyex plurality of gas ‘inlet openings therethrough, the tinguish the arc. other of Vsaid are :terminal members 'having a JOSEPH SLEPIAN.