Патент USA US2134506код для вставки
Oct. 25, 1938. H. BUCHWALD ET AL ELECTRIC CIRCUIT INTERRUPTER - 2,134,506’ Oct- 25, 1938. H. BUCHWALD Ef AL 2,134,506 ELECTRIC CIRCUIT INTERRUPTER Filed June 10, 1935 Sheets-Sheet 2 Inventors: - - Herbert Buchwald, Erwin Marx, by X] l .T heir) Attonneg. _ Patented Oct. 25, 1938 v 2,134,506 UNITED STATES PATENT OFFICE 2,134,506, _ ELECTRIC omcorr INTERRUPTER Herbert Buchwald, Berlin-Reinickendorf, and Er win Marx, Braunschweig, Germany, assignors to General Electric Company, a corporation of New York Application June 10, 1935, Serial No. 25,904 In Germany June 12, 1934 5 Claims. (Cl. 200-—,148) The invention relates to electric circuit inter rupters, more particularly to circuit interrupters of the gas-blast type wherein a jet of gas or ?uid from a suitable source of pressure is utilized for interrupting arcing upon opening of the circuit. :1 Heretofore in extinguishing the arc upon open ing of the circuit by gas or a ?uid such as air under pressure, the ?ow of gas was so adjusted that an intensive cooling of the arc was obtained. It has likewise been proposed to increase the arc extinguishing effect by locating both bases or. roots of the arc at so-called arcing tips which areseparate from the contact making parts. Whatever favorable effect these arcing tips have 15 on the interrupting capacity of the circuit inter rupter is mostly attributable to the fact that they oppose, to a limited extent, the gases flow ing from the actual arc chamber. This fact has, however, not been recognized prior to the present 20 invention. The main object of the present invention is an improved method of circuit interruption and the correct formation of the electrode and contact structure in circuit interrupters of the aforesaid 25 type for increasing the effectiveness of the arc interrupting gas blast. _ For an understanding of the nature of this in ' vention, consideration of the following principles is necessary.. If the are upon opening of the 30 circuit is to be extinguished with the minimum of trouble, that is with the smallest quantity of gas at comparatively low gas pressure, care must be taken that during the arcing period and until the passage of the arc current through zero the 35 arc developsv the smallest possible amount of heat in the arc chamber. To this end it is neces sary that the voltage drop across the arc be kept as small as possible during the main arcing period. 4O The are should, therefore, notbe im concentrated jet must be completely dissipated. This result is not effected at all or in any event only to a very small extent by previously known forms of arcing tips. In the case of these arcing tips, there is fur ther the possibility that the points of the base of the arc will not remain at the ends of the arcing tips, but will be driven by the gas ?ow longitudinally along the sides thereof so that undesirable lengthening of the arc results. This possibility is likewise preventedby rapidly de fleeting the gas flow in the radial direction as above described. - The invention will be more fully set forth in the following description referring to the accom panying drawings, and the features of novelty which characterize our invention will be pointed out with particularity in the claims annexed to and forming a part of this speci?cation. Referring to the drawings Fig. 1 is an eleva tional view partly in section illustrating diagram matically a form of our invention wherein the electrode structure is shown in the open circuit position; Fig. 1a is a similar view showing the electrode structure in the closed circuit position; ‘Fig. 2 illustrates another form of our invention wherein the electrode structure is shown in the open circuit position; Fig. 2a is a similar view showing the electrode structure in the closed cir cuit position; Fig. 3 is an elevational sectional view of an electric circuit breaker of the gas blast type having incorporated therein the electrode. structure shown by Figs. 1 and 1a. In accordance with this invention one or more de?ecting bodies are positioned so as to oppose the gas ?ow with respect to the longitudinal axis, and are so formed that they likewise change the direction of gas ?ow. Furthermore, the eddies in the gas ?ow which cannot be avoided along the axis of the electrode arrangement and its im moderately lengthened. Furthermore, it should be subjected only to the smallest possible trans ' mediate surroundings with the sharp de?ection verse blast, that is, to a gas jet at right angles to the longitudinal axis of the arc. To this end it is primarily necessary that the velocity of the 45 gas flow beyond the exhaust openings, such as in hollow or ring-shape electrodes, be reduced as rapidly and as much as possible. This cannot be effected solely by enlarging the cross-sectional ?ow. For this purpose, in accordance with the pres ent invention, a comparatively great de?ection of the direction of ?ow is necessary. In the usual case the gas ?ow is through the hollow electrodes in an axial-direction. It must be deflected back 55 in approximatelyradial direction, that is, the of the ?ow are, under certain circumstances, even made advantageous. For the purpose of de?ect ing the gas flow in accordance with this inven tion, the surface of the de?ecting body opposing the gas flow may be either ?at, concave or con vex in any suitable form. 1 Referring more particularly to Fig. 1, there are illustrated at the upper and lower hollow electrodes l and 2, respectively, different forms by way of example, of the above described deflect ing body. The electrodes I and 2 may be ?xed in spaced relation, such as in a lightning arrester, or may be relatively movable such as in circuit breakers for example. Fig. 1a illustrates the 2 2,184,506 electrodes in the closed circuit position when operating as a circuit breaker. The de?ecting body 3 associated with the elec trode 2 is of large diameter as compared with the passage 2' through the electrode 2. The de ?ecting surface at 3' may be made concave or convex in accordance with the particular design of the electrode structure. The de?ecting portion 4 which is associated with the electrode l is of slightly smaller diam eter than the passage 2' in the electrode 2. The electrode I is provided with a passage l ’, as illus trated, extending from the lower surface thereof directly in alinement with the de?ecting body 4. 15 The passage I’ has exhaust ports at the sides of the electrode as illustrated. According to this invention, the diameters of the de?ecting surfaces are comparatively large although the diameters should not greatly exceed 20 the openings in the hollow electrodes. Moreover, it is necessary that the hollow electrode’ and de?ecting body be spaced a small extent so that complete de?ection of the entire cross section of the gas ?ow is obtained. 25 In the case of high voltages, however, if the de?ecting body is very close to the hollow elec trode, provisionmust be made for preventing reignition of the arc after extinguishing of the same by the gas ?ow due to the fact that parts of 30 ‘the electrode structure remain at high tempera ture for a short time. Reignition of arcing may be prevented in accordance with this invention by forming the hollow electrodes so that they func The arrangement shown by Fig. 2 comprises a de?ecting body 3 wherein the de?ecting sur face 3' is generally of conical shape extending away from the direction of gas ?ow. The de?ect ing body 4 associated with the electrode 2 in the present instance is provided with a central bore in which a movable contact rod 5 is posi tioned. In the closed circuit position as shown by Fig. 2a the rod 5 is elevated so as to engage the de 10 ?ecting member 3, and in the circuit opening operation the rod 5 serves as an arcing tip. It will also be apparent that the arrangement may be similar to that of Fig. 1. That is, the elec trodes I and 2 may engage and the rod 5 serve as 15 an arcing tip at the de?ecting member 4. I In the present instance the de?ecting member 4 may consist of metal or insulating material, or it may be coated with an insulating material, so that the points of the arc base are limited to 20 predetermined positions on the electrode struc ture. The circuit opening operation is essentially the same as that described in connection with Fig. 1, the electrode structure of Fig. 2 being par ticularly adapted for circuit breakers or switches 25 of the gas blast type. However, it will be ap parent that the rod-like de?ecting member 4 of Fig. 1 may be movable as in Fig. 2 to bridge the electrodes l and 2. In addition to the above described advantages, 30 in so far as arc interruption is concerned the sharp fan-like de?ection of the gas current and the change of cross-sectional ?ow likewise occur tion as an electric screen or shield for the de ' 35 ?ecting surface. ring result in damping of the sharp switching The circuit interrupting operation is performed noise characteristic of the gas blast switch. This factor may be taken into consideration in' the by directing gas under pressure from a suitable source between the electrodes I and 2 as indicated by the directional arrows. The gas ?ows axially 40 through the passages I ' and 2' in opposite di rections substantially parallel to and around the are between the electrodes l and 2, each jet be design of the de?ecting bodies. In the circuit interrupting method above de scribed, it is immaterial in principle whether one creased radially of the base of the arc. The are with respect to the arc previous to the extinction of the arc is chie?y taken into account. Accord ingly, a decrease for example of the gas used for extinguishing the arc and an increase of the or two exhaust ports for the gas are used in the circuit interrupter, since with the selection of 40 such a design the determining considerations ing sharply de?ected at the de?ecting surfaces 4' concern the most favorable ionization and re and 3’ so as to assume a substantially fan-shape moval of metallic vapors. In the case of the ?ow. The direction of ?ow is, therefore, abruptly present invention the application of the gas ?ow changed and the velocity is likewise greatly de which is not appreciably lengthened by this method, and therefore does not build up a great 50 counter-pressure, is e?ectively interrupted at a subsequent current zero. In the circuit breaker shown by way of example by Fig. 3, the electrode structure corresponds in form and position to that shown by Fig. 1. The ?xed electrode struc 55 ture 2-3 is disposed at one end of an insulating housing H, and the coacting relatively movable electrode structure i-4 is guided for vertical reciprocal movement in the opposite end wall of said housing. An insulating partition P is 60 mounted within the housing so as to con?ne the ?ow of gas at the electrode l as previously de scribed. When gas under pressure is admitted as in dicated, such as through laterally disposed gas supply conduits, to the intermediate part of the‘ housing H upon separation of the contacts, the arc is interrupted in the manner previously de scribed, the gas exhausting in opposite directions past the electrode structures as illustrated by the directional arrows. Actuation of the movable electrode structure l—4 is accomplished by means of suitable operating mechanism (not shown). The ?xed and movable electrode structures can be connected respectively to the external circuit 75 terminals as diagrammatically indicated at T. interrupting capacity and of the voltage rating are obtained. 50 It should be understood that the invention is not limited to speci?c 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 55 spirit of the invention. What we claim as new and desire to secure by Letters Patent of the United States, is: 1. In a gas blast arc-interrupting system, the method which comprises directing gas under 60 pressure at high velocity around and longitudi nally of the axis of the arc to be interrupted in opposite directions toward both of the roots of said are, and sharply de?ecting the ?ow of said gas adjacent said roots radially from said axis. 2. An electric circuit interrupter of the ?uid blast type comprising coacting electrode struc ture forming a centrally disposed ?uid passage, said electrode structure separable to form an arc 70 longitudinally of said passage, means for direct ing a ?uid under pressure into said passage at an intermediate point so as to ?ow longitudinally of said are without traversing and lengthening the same, and a de?ecting member at one end 75 3 v 2,184,506 of said passage for sharply de?ecting the ?ow of said ?uid away from and substantially radially 01' said are. ' 3. An electric circuit interrupter of the gas blast type comprising a pair of hollow electrodes, arcing means between which an arc may extend through said hollow electrodes, means interme diate said electrodes for directing a ?ow of gas through said electrodes in opposite directions so 10 as to flow longitudinally of said are without lengtheningthe same, and de?ecting means asso ciated with each of said electrodes at points adjacent the arc roots respectively, said de?ect ing means being positioned at the exhaust open 15 ings of said electrodes and arranged so as to de?ect sharply the flow of said gas away from and generally radially of said arc. 4. An electric circuit interrupter of the gas blast type comprising coacting electrodes, one 20 electrode having a gas passage therethrough, said electrodes separable to form an are upon opening of the circuit within said passage, means v for directing flow of gas under pressure laterally of and into said passage and parallel to said are without substantial traversing of the arc, and a de?ecting member closely spaced with respect to the exhaust opening of said electrode passage and arranged so as to de?ect said ?ow at said exhaust away from and generally radially of said are. > 5. An electric circuit interrupter of the gas blast type comprising a pair of electrodes having alined gas passages therethrough, a contact rod 10 movable through said passages for opening and closing the circuit, means for directing ?ow of gas under pressure from a point intermediate said contacts through said gas passages so as to ?ow in opposite directions substantially par 15 allel to an are formed upon the circuit opening movement of said contact rod, and de?ecting members associated with each of said electrodes adjacent the exhaust openings of said passages for de?ecting said gas away from the arc in fan like ?ow. HERBERT BUCHWALD. ERWm MARX.