Патент USA US2130999код для вставки
Sept. 20, 1938. RMICHL 2,130,999 Z9 \ I3 w a 5” QPJMW ' Sept. 20, 1938. , F. PET-ERMICHL 2,130,999 ELECTRIC CIRCUIT INTERRUPTER Filed Feb. 15, 1937 \ 3 Sheets-Sheet‘2 A .\+ , I ‘ Inventor : F‘T'amz peter'rnichl, His Attorney. Sept. 20, 1938; F. PETERMICHL . ' Filed Feb. 15, 1937 2,130,999 I s Sheets-Sheet s 33 nsulatio‘n 1I 3 Z0 I‘?venbov. Franz ‘Pebewvmic'hl, w x/ 54W M745 Abtovneg. Patented Sept. 20, 1938 ' 2,130,999 UNITED STATES PATENT OFFICE. 2,180,999 ELECTRIC CIRCUIT INTERBUPTER Franz Petermichl, _Berlin-Charlottenbnrg, Ger many, assignor to General Electric Company, a corporation of New York ' appucauon February 15, 1937, Serial No. 125,919 - In Germany February 28, 1936 6 Claims.- (Cl. 200-149) My invention relates to electric circuit inter back is obviated in a simple manner by dividing rupters of the expulsion type wherein an arc-ex up the quenching channel which isformed by ‘gas yielding materials and through which the contact point of the movable contact is drawn when open tinguishing gas is generated upon opening of the circuit by the action of thearc on a material close ly con?ning or in direct contact with the arc. The gas so generated is suitably directed so as. to cause interruption of the arc. ‘ More particularly, the invention is concerned with an electrical switch wherein the arc is D quenched by means of pressure gas. The gas is liberated by the arc to be interrupted in ‘a switch tube, which consists of rigid materials adapted to ing the circuit, in such a way that adjoining the 5 ?xed switch contact there is an arc quenching’ channel structure whose length is dimensioned for the interruption of large currents. The channel then comprises an intermediate expansion or blow-out chamber wherein the large currents are 10 interrupted. A further quenching channel is in communication with the expansion chamber and emit gas under the in?uence of heat, or is lined , its length is so dimensioned that it produces to with such materials. More speci?cally, in a pre ferred form of my invention the contact point of the movable switch member, from which the arc extends to the ?xed or counter-contact after con tact separation, is moved directly through an arc quenching passage or channel wherein the arc U gether with the ?rst quenching channel structure the requisite length of switch tube for certain 1‘ quenching of the arcs of small currents. The in termediate expansion or-blow-out chamber can be closed except for the passage openings for the movable switch member. It can, however, also be quenching gas is produced by the contact of the vented to the surrounding air by means of an ex- 20 ' arc with the inner gas-yielding walls of the pas haust passage extending to the blow-out end of the switch tube, or by means of openings provided in the switch casing. Under certain circum stances as hereinafter described it may be expe dient to arrange valves in those openings. 25 My invention will be more fully set forth in the following description referring to the accompany sage. , In each case the quantity of liberated arc quenching gas depends on the intensity oi’ the our 5 rent to be interrupted, on the size of the surface of the switch tube in contact with the are and on the duration of the arc. Consequently, in order to produce the quantity of gas required for the quenching of small currents, it is necessary to J use a longer switch tube than for the quenching process of large currents. However, a long switch . tube, dimensioned for the quenching of small cur rents, works out unfavorably when switching of]! large currents. That is, since the quenching, of 5 thearc is generally e?ected directly when the contact point of the movable ‘switch member un ing drawings, and the features of novelty which characterize my invention will be pointed out with particularity in the claims annexed to and 30 forming a part of this speci?cation. , Referring to the drawings, Fig. 1 is an elevation al, sectional view of an electric circuit breaker em bodying the present invention, and Figs. 2 and 3 thereby releases a quenching blast, the burning are similar views of other forms my invention may 36 assume. The switch as shown in Fig. 1 is constructed in accordance with the invention and consists es duration of the arc . is unnecessarily prolonged sentially of two tubular pieces I and 2 of gas ) when switching o?- large currents. During this entire additional period, ‘however, the insulating within a supporting sleeve or casing 3. The cham material linings and the switch contacts are sub ber so formed between the same comprises an ex covers the blow-out end of theiquenching tube and yielding insulating material, which’are spaced 40 jected to great stress by the powerful arcs, with out aiding the actual quenching process. pansion or blow-out chamber 4. Inthe con structional example, an exhaust channel 5 vents 5 The result is a greater wear and deterioration of the intermediate channel or expansion chamber 45 the gas-yielding material and of the contact ma- ' 4 to the blow-out end of the switch tube, at the terial, and also excessive and unnecessary stress opposite closed end of which the ?xed contact 6 upon- the arc chambers by the pressure of the is arranged. 'This contact coacts with the tube heated gases produced by the arc. shaped movable switch member 1, into which a ) A'principal object of the present invention is the bolt 8 of insulating material projects from the 50 provision of an improved circuit interrupter of the base of sleeve 3. The members I, 2 and 8 are com aforesaid type which is e?icient, reliable and posi posed ‘of a suitable gas-yielding material such as tive in operation throughout the entire range of, fibre and closely con?ne the arc during the in its interrupting capacity. ; , According to my invention, the aforesaid draw terrupting process. . When switching of! large‘ currents, considera- u .2 arouses ble quantities or" gas are liberated from the insu lating tubular structure I! by the are. Directly the contact point or tip of the movable contact 7 leaves the structure l , a quenching stream of gas is released and directed as indicated in the direc tion of the expansion chamber ll, owing to the pressure difference between the compartment en of the extinguishing tube at the ?xed switch con-‘ tact, of single plates, which are arranged in cornpassing the ?xed contact layers with the interposition of spacers and the expansion. Aper chamber fl. _ As a result of this gas blast the arc tures are provided in these plates, =. is quenched, without ice-ignition. into a suitably positioned discharge duct. mode of execution according to this aspect of the invention, in the application to gas expul~ sion switches wherein the switch tubes consist of a cylindrical part with concentrically inserted bolts of insulating material, and the movable the arc during the further course of the switching-off stroke of the movable switch member, by reason. of the fact that the gases still remaining under pressure in the tube i and in the intermediate chamber ll insulate the, contact the recovery voltage. Heavy current arcs are therefore interrupted be fore the contact '1 enters the tube On the other hand, when interrupting small currents, the quantity of quenching gas liberated 20 within the spaces forming the expansion cham ber. During this operation the movable switch member keeps the exhaust end of the extinguish ing tube closed. It is especially advantageous to make the end the are from the ?rst inst ng tube is so '1 open switch member consists of a'tube contact, as in. the case of Fig. has the following material advantage. It has been observed that in tube contacts, the base of the are at the lower contact edge heats up the metal. of the contact to its slight that it does not suirlce the quenching of the arc and insulation respect to the recovery voltage. Instead the are is drawn fusion point, and that the extinguishing gas di» rested in the direction of the circuit opening movement blows the fused particles of the con through the intermediate chamber d and con- ' tact into the narrow gap between the tube con“ 25 tinues within the tube 2. Accordingly the devel tact and the walls of the switch chamber. opment of gas increases to such an extent that Thereby the surface of the tube contact is given the main quenching blast set up upon emergence a rough coating which upon hardening has a of the movable contact 'i from the exhaust open destructive effect on the walls of the extinguish“ ing of the switch tube causes the arc to be ing tube particularly when switching on again. 30 quenched. in the arrangement according to my invention arcs of great current inten 4" therefore quenched more quickly than 'herto. Conse quently the wear'and deterior .uori of the switch parts under the in?uence or" the arc and the stress upon the parts exposed the pressure of the switch gases are less than they were hitherto. rfhis limiting or” the arc duration in the case of large currents is of especial importance in con— 40 nection with the contact wear tor the reason. that the metal parts which are greatly heated~ up in the ?rst'half-cycle of the are thereafter sub ject to greater deterioration. wear in= creases in a far greater progression than corre sponds with the are duration. A further advantage of the arrangement ac cording to my invention is that the hot gases produced when switching off large currents are not conducted directly through the tube 2 which is utilized for the quenching or the small cur rents. The gases are instead cooled in the inter“ mediate compartment ll through expansion, so that only the tube l is essentiallyr subjected to wear due to heavy ‘current arcs. Consequently At the same time, however, a breach or depression originates naturally in the edge of the tube com ‘tact at the base of the arc. "Upon the next switching operation the base of the arc is driven upwards to the edge of the tube contact under the in?uence of the extinguishing gas current, until it comes to rest at the breach, and the process described above is repeated with the .result that the becomes deeper and deeper, and a very uneven biu'nir g of the tube contact ‘takes place, whi h therefore repaired prematurely. Ti‘his disadvantage be overcome by the present form of the invention, since the direction of the gas blast, as long as the tube contact l ens the exhaust end of the tube closed, will be essentially opposed to the direction of movement of the tube contact. Finally, according to this aspect of the lnven~ tion, the apertures in the plates forming one end of the extinguishing passage can be displaced opposite each other, as for example along a spiral path. By this means the points of the are which are subjected to the strongest transversal blast, i. e. in the air pockets or expansion spaces be when switching off large currents, the‘ chamber will remain better suited to the interruption of tween the single plates of the insulating gas yielding material, are displaced spirally in the small currents than ‘would a chamber, without an arrangement according to the invention, which is subjected to wear along its entire length promoting the extinguishing of the arc, is when switching off large currents‘. In certain circumstances it may be expedient Referring more particularly to Fig. 2, 2i indie to make the tube structure i of more than one piece of gas-yielding material such as of individ ual plates provided with bores and stacked in, spaced layers. The expansion chamber is formed by the spaces between the plates. Fig. 2 illustrates such an arrangement. I 'As in the previous case the object consists in ‘guaranteeing safe extinguishing of the are not 70 only at highand low current values but also at critical medium current intensities. This object is attained in'the present case by so constructing the switch tube adjacent the ?xed switch contact of gas-yielding material that the arc is subjected 75 to a transversal blowing and lengthening thereof same manner. attained. "in this way rotation of the arc, ’ cates the switch chamber, which surrounds the ?xed tulip-shaped contact 22 and cooperates with the movable tube shaped switch contact 23. The switch chamber is formed by a generally tu bular structure made of insulating material ca a. pable under in?uence of the arc of giving oil? gas. The tubular structure comprises an integral tube 24 at the exhaust end, and single ‘discs 25 in the region of the ?xed contact 22. The discs 25, which have centrally alined apertures for the contact 23, are spaced by members 26, and to gether with the fixed tube 24, form a continuous passage for the passage of the movable switch tube 23. Within the passage 2. bolt 21 of insu~ lating material, appropriately, of material 3 2, 180,999 adapted to give o? gas, is arranged concentrical ly. The bolt 21, positioned centrally of the con tact tube 23, is ?xed to the cover 23, which in the form shown by way of example, surrounds the ?xed contact 22 and also the end of the ex tinguishing tube formed by the discs 25. ,Apcrtures 25’ are provided in the discs 25 and are arranged in superimposed position, as shown, or displaced with respect to each other. The ) extinguishing gases exhausting through the in termediate spaces forming the expansion cham ber between the plates and through the aper tures 25, can escape freely through passages 24' in the tube 24. 5 ‘ Under certain circumstances for attaining as powerful a transverse blast between the discs as possible, a packing 23' can to advantage be lo cated in the ?xed tube 24 for preventing initial exhaust of the extinguishing gases along the tube 6‘ contact 23, as long as the contact is within the into the intermediate expansion chamber, in ac cordance with the strength of the current to be switched o?. ' - These di?lculties are obviated, in accordance with the present form of my .invention by sep arating the intermediate chamber, preferably in direct communication with the outer air, from the gas-forming chamber proper, by an auto matically operating valve, such as an annular slide valve, for bridging the space between the 10 two gas-yielding tube-pieces. In accordance with the interrupting condi tions, the annular slide-valve opens more or'less in response to one component of the compressed 15 gas in opposition to the force of a spring. With a development of this kind, the small currents .also, are reliably quenched by the gas ?ow, as the movable switch rod passes out of the first part of the quenching tube. Surprisingly, a phenomenon, favorable to the voltage arc 20 quenching, is that the arc voltage is slight, both when switching-out small as well as great cur the interior or the-recessed cover 28, projections rents. Besides this a further advantage is that 28' for retaining the plates 25 and their spacing the annular slide also can if desired be made ;5 rings 26. The plates and rings are held'in this , of gas-yielding material, although advantageous 25 extinguishing’ tubes. A simple assembly of the switch chamber is also possible by providing in position by screwing the fixed insulating tube 24 into the cover 23 as shown. The manner of operation of the gas expulsion switch according to the present form of my in ;0 vention, is as follows: The arc l3, which is drawn between the con ‘Wtacts 22 and 23 upon switching off immediately develops extinguishing gas from the gas-yielding walls at 25. This gas is under pressure as com ;5 pared with the surrounding ,. air. The result is that the arc is driven into the intermediate ex pansion space between the plates 25 and under goes considerable lengthening, so that its resist ance is weakened.‘ Since at this time the path 40 through the exhaust end of the extinguishing tube is entirely or for the most part blocked ly of a somewhat less readily vaporizing material, and can thus be utilized for developing quench ing gas.‘ . Referring more particularly to Fig. 3, the unching chamber of the gas-switch is formed 30 by the two pieces of tube 3| and 32 which are composed of a material adapted to give of! gas under the in?uence of the arc, and which are spaced in a supporting body 33. At one end of the tube 3| is provided the fixed contact 34, which cooperates, in the embodiment shown by way of an example, with the movable 'tubular switch contact 35. A bolt 36 of insulating material, preferably of gas-yielding material, extends into the contact 35 from the closed end of the sup porting body 33. The chamber 31, disposed be against the extinguishing gases, they necessarily tween the tubes 3| and 32, is in communication ‘?ow through the intermediate spaces between the vwith the outside air, directly or indirectly, plates, through the apertures provided therein, 45 to the discharge passage in the fixed extinguish ,ing tube 24. A, powerful transverse blast is therefore directed through the are at several places at the same time. - The combined action of both these phenomena, 50 practically insures together with the later main extinguishing blast at the exhaust of the ex tinguishing tube, a safe extinguishing of the arc for both small and medium currents as well as with large current. As in the case of Fig. 1 small currents are readily interrupted within the. 55 tube 24. _ . The dimensions of 'the apertures 25' and of the passages 23' must of course be chosen in such a manner, that upon the extinguishing of [30 large currents, notwithstanding the direct con nection with atmosphere, an adequate extin guishing pressure can build up in the switch tube. through apertures 38. - _ In accordance with my invention, an annular slide valve 39 is mounted on the tube-member 32 and is under the in?uence of a spring 3|]. The valve is provided with a pressure-surface 39' which is acted upon by the switch-gases, and is of suitable form, as a conical turned-down part, for instance. In its closed or normal position, it seats on the casing 33 carrying the tube-mem ber 3|. The annular slide 33 may also consist of gas-yielding material and may, of course, if desired be guided on the other tube-member 3| 55 or in the walls of the casing 33. The operation of this form of the gas-switch, in accordance with my invention is as follows: On switching off a current of any magnitude, a quantity’ of quenching-gas is first freed from the tube-member |. The gases so developed un-‘ der pressure move ‘the slide 39 more or less away Fig. 3yillustrates an arrangement fundamen from the casing 33 and a blast ‘takes place tally similar to Fig. l and comprises an improve through the annular gap so formed, into the in ment in a gas expulsion switch of this kind. It > termediate or expansion chamber formed by the 65 has become evident, that the cubic contents of casing 33. This blast quenches the arcs of great the intermediate or expansion chamber must and also of comparatively small or medium cur be sufficiently great for the generation of an adequate blast forthe quick quenching of large 0 current arcs and that, on the other hand, when the intermediate chamber is restricted in volume, smaller currents, even at higher voltages, can be better interrupted. These requirements, opposed to each other, can be met by providing valves 5 which regulate the inlet of the quenching gases rents. ' With quite small currents, on the‘other hand, 70 the slide 33 remains closed so, that the arc pas sage is restricted and the gas formation, requi site for the switching-off of these currents, pro ceeds unhindered until the contact point of the movable switch member leaves the quenching arouses ‘tube. At this point, the exhaust lolast effective ly interrupts a lingering are. can subsequently be drawn, said plates and cyl lit should be understood that my invention is not limited to specific details of construction and arrangement thereof herein illustrated, and that changes and modi?cations may occur to one skilled in the art Without departing from the spirit of my invention. ‘it/‘hat I claim as new and desire to secure by Letters Patent of .c13 States 1. An electric circuit interrupter the gas expulsion type comprising relatively movable contacts, and a casing including insulating struc ture for substantially enclosing con?ning the are formed at said contacts along substan tially longitudinal path upon opening of the cir~ cult, said casing betig closed at one end at which initial. contact separation takes place, said in» sulating structure forming adjacent said closed end an expansion chamber arranged directly to he vented to a low pressure area for the inter ruption of comparatively large currents and a restricted longitudinal passage adapted. to com municat/e with said expansion chamber, the arc » formed at said contacts being initially drawn through said expansion chamber and subsequent ly iii the case of a persisting are through said said arc,.spaces between said plates being vented to atmosphere independently of restricted bore so that the gas pressure generated upon initial. formation of said arctends to force said are laterally between said. plates. ' An electric circuit interrupter, of the gas expulsion type comprising relatively movable con tacts, and insulating stru Sure arranged to form con?ning passage for ‘- 1e arc drawn between said contacts upon opening of the circuit, said insulating structure adjacent one of said con-1 tacts closely con?ning in. sleeve-like relation the arc the initial formation thereof and at a point remote from said contact consisting of a cylindrical member likewise closely confining said arc, said con?ning passage including an expan sion chamber vented to atmosphere interposed between said cylindrical passages, said insulating structure at said passages being composed of a material adapted to emit an arc~extirwuishing gas When 5. An subjected electric to circuit said are. interrupter of the expul sion type comprising relatively movable contacts, restricted passage, said insulating structure ad insulating structure arranged to form a confining jacent to the point of initial formation of said passage for the are drawn between said contacts are in said expansion chamber and in said re upon opening of the circuit, said insulating struc ture adjacent one of said contacts consisting of stricted passage being composed of a material adapted to emit an arc-extinguislung gas When subjected to said arc. 2. An electric interrupter of the gas expulsion type comprising a ?xed contact, a co spaced plates having substantially aliuecl aper tures through ‘which said are is dravm, said plates also having apertures interconnecting the spaces between said plates, said insulating structure also acting movable contact, and a casing including insulating structure for mounting at one end thereof said fixed contact, said being closed comprising at a point remote from said contact a cylindrical member having bore restricted at said end, said structure arranged to form a which said are car; subsequently be drawn, said plates and cylinder being c ‘nosed of material con?ning substantially enclosed passage tor the are between said contacts upon opening of the circuit, said passage being enlarged adjacent said with respect to the other? adapted to contacts through an arc-extinguishing when subjected to said 5. An electric circuit interrupter of the expul ?xed contact to form an expansion chamber ar ranged to have a direct exhaust to atmosphere, sion type comprising relatively movable contacts, " being restricted with respect to said movable co: ct at a point remote from said 1 seal contact, and insulating structure for confining the are formed at said contacts upon opening of the cir said insulating structure immediately adjacent to cuit, said insulating structure defining an ex pansion chamber adjacent the point of initial separation of said contacts and also including a cylindrical member for ‘defining restricted pas said ?xed contact being composed of material adapted to emit an arc-extinguishing gas when subjected to said arc. 3. An electric circuit interrupter of the gas :1 LI inder being composed oi’ a material adapted to emit an arc-extinguishing gas when subjected to expulsion type comprising relatively movable con tacts, and casing including insulating structure sage in communication with said expansion chamber through which the are can subsequently be drawn, one of said contacts being movable arranged to form a con?ning passage for the are through said-restricted passage, said expansion drawn between said contacts upon opening of the circuit, said casing adjacent one of said contacts enclosing a plurality of spaced plates having sub chamber being vented to exhaust at a point ad— jacent the exhaust of said restricted passage in dependently of said restricted passage, said in sulating structure including in part a material adapted to emit an arc~eirtiziguishiug gas when subjected to said are. stantially alined apertures through which said are is drawn, a cylindrical member having a s1eeve~1ilre bore restricted with respect to the other of said contacts through which said arc FRANZ PETERBMCHL.