US2443017A - Electric arc extinguishing apparatus - Google Patents

Description

N. F. ARONE ErAL 2,443,017

ELECTRIC ARC EXTINGUISHING APPARATUS `une 8, 1948.

Filed July4 18, 1944 2 Sheets-Sheet l Inventors Eugene W. Boehme,

Nicholas FT Arone,

N. F. ARONE ETAL ELECTRIC ARC EXTINGUISHING APPARATUS June 8, 194s.

a m mmm h @BAMw 2 vnl ,mmww .m e u h EN T Filed July 1a, 1944 Patented 'June 8, 1948 UNITED sTATEs PATENT OFFICE ELECTRIC ARC EXTINGUISHING APPARATUS Nicholas F. Arone, Upper Darby, and vEugene W. Boehne, Drexel Hill, Pa., asslgnors to General Electric Company, a corporation of New York Application July 18, 1944, Serial No. 545,460

(Cl. 20o-147) 16 Claims.

scription proceeds 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 specification.

For a better understanding of our invention reference may be had to the accompanying drawings in which Fig. 1 isa sectional view of an electric circuit interrupting device embodying our invention;.Fig. 2 is a sectional view taken along the line 2 2 of Fig. 1 looking in the direction of the arrows but showing a complete device; Fig. 3 is a fragmentary view similar to Fig. 1 of a modification oi' our invention; Fig. 4 is a sectional view taken along the line 4 4 of Fig. 3 looking in the direction of the arrows but showing a complete device; Fig. 5 is a fragmentary view similar to Fig. 3 of another modification of our invention; Fig. 6 is a partial perspective view of another modiilcation of our invention; Fig. 7 is a sectional view taken on line I--l of` Fig. 6; Figs. 8 and 9 are partial perspective views of other modiilcations of our invention; Fig. 10 is a sectional view taken on line IU-IIl'of Fig. 9, and Fig. 11 is a partial perspective view of still another modiflcation of our invention.

Referring now to Figs. 1 and 2 of the drawing, we have disclosed our invention yas applied to an air circuit breaker comprising a plurality of relatively movable contacts. As' illustrated in the drawing, these contacts comprise a pair of stationary current carrying contacts I and 2 connected to line terminals 3 and 4, respectively. Stationary contacts I and 2 are adapted to be bridged by movable current carrying contact 5 mounted on a movable operating rod 6. Suitable springs 1 may be provided between rod 6 and movable current carrying contact or bridging member 5 to give the desired contact wipe. Preferably the circuit breaker is also provided with arcing contacts comprising movable arcing contact 3 adapted to engage stationary arcing contacts 9 and I0. Preferably arcing contact 8 is formed of Van arc resistant material and is bifurcated as shown at II in order to provide a spring action with reference to engagement with stationary arcing contacts 9 and I0.' between which movable arcing contact 3 is wedged.

The relatively movable contacts described above are associated with an arc extinguishing chamber embodying our invention and generally indicated at I2 which comprises a pair of arc runner enclosures in the form of expulsion tubes I3 and I4 preferably formed, or at least lined with an insulating material of a type which evolves gas when subjected to the heat of an electric arc. In the embodiment of our invention shown in Figs. 1 and 2 the arc runner enclosures comprising expulsion tubes I3 and I4 are arranged closely adjacent each other in parallel relationship. Each of the expulsion tubes I3 is provided with a narrow, longitudinally extending slot I6. The sloteln one tube, such as I3 for example. is arranged to face the slot in the tube I4 and be substantially coplanar therewith, so as to deilne a narrow arc extinguishing passageway I6 between expulsion tubes I3 and I4. As shown, the width of this longitudinally enclosed passageway is materially less than the width of the opening in the tubes I3 and I4.` This passageway is also-bounded by insulating material which may be of the gas evolving type and which may either be integrally formed with expulsion tubes I3 and I4, as is illustrated in Fig. 2, or may comprise a separate insert, as is illustrated in Fig. 4. Preferably the arcing contact Il extends into the lower end of the passageway I6 and the stationary arcing contacts 9 and III extend to the edges of the passageway I6, as is clearly indicated in Figs. 1 and 2.

In order to accelerate the arc drawn at the lower end 0i' the passageway I6 into arc runner enclosures comprising expulsion tubes I3 and I4, we provide in each expulsion tube I 3 and I4 an arc runner II which may be integrally formed with its associated stationary current carrying contact I or 2 and stationary arcing contact 9 or I0. Arc runner I1 extends longitudinally o f tubes I3 and I4 and is preferably provided with a tip oi arc resistant material I'I.

For the purpose of producing a magnetic field in the'arc space within the arc runner enclosures comprising expulsion tubes I3 and I4 for assisting electromagnetically the rapid movement upward of the arc in the expulsion tubes, we preferably provide a `tube of magnetic material I8 surrounding each of the expulsion tubes I3 and I4. As shown, the expulsion tubes I3 and I4 are cylindrical and alsothe tubes I8 are cylindrical and concentric with the expulsion tubes. The tubes I8 being of magnetic material also greatly increase the bursting strength of the arc extinguishing chamber I2 of our invention. It will be obvious that they must also be provided with slots corresponding to the slots in expulsion tubes I3 and I4 in order properly to accommodate the expulsion tubes I3 and I4 with' the passageway I6 therebetween, as is clearly shown in Fig. 2. Also, since the magnetic tubes I8 are approximately c-shaped, the magnetic expulsion action is more intense in the passageway adjacent the slots I than in the tubes I3 and I4. A suitable gas barrier Io is provided in arc extinguishing chamber I2 below stationary arcing contacts l and I0.

In view of the detailed description included above, the operation of the circuit breaker embodying our invention will be obvious to those skilled in the art.

Although in Figs. 1 and 2 We have specifically illustrated our invention as being applicable to a circuit breaker having relatively separable contacts, it is also equally applicable to circuit interrupters of the type employing a fusible or meltable metal. Accordingly in Figs. 3 and 4 I have illustrated an arc extinguished chamber which in most respects is substantially identical with the arc extinguishing chamber I2 of Fig. 1 except that it is adapted for use with a fusible element rather than with the relatively movable contacts of Figs. land 2. The corresponding parts of Figs. 3 and 4 are designated by the same reference numerals as in Fig. 1. A fusible element 2i is provided within passageway IB. This fusible element extends through openings 2l and 24 in expulsion tubes I3 and I4, respectively, so that the ends thereof may be connected to terminals 3 and 4. A gas :barrier 2B of insulating material and a tubular member 21 close the bottom of the arc extinguishing chamber 2li except for a central opening leading to passageway I0.

In Fig. 5 we have illustrated our invention as being applicable to a lightning arrester, and arc extinguishing chamber 28 is substantially identical with the arc extinguishing chamber 20 of Fig. 3, except that the fusible element 2i is replaced by a pair of spaced electrodes 29 and 30 electrically connected to arc runner I1. The corresponding parts of Fig. 5 are designated by the same reference numerals as in Fig. 3.

We have found that an arc extinguishing chamber built in accordance with our invention will interrupt 9000 amperes at '7,250 volts when the diameter of the bore of expulsion tubes II and I4 is 1% inches with the tubes 10 inches long and the passageway I6 is 1,/8 inchby 3 inches.

From the above discussion it will be obvious that the new and improved arc extinguishing chamber of our invention is applicable to various forms of circuit interrupting devices, such as circuit breakers, fuses, and the like. In the arrangements described thus far the are extinguishing chambers have been substantially identical in that they comprised a pair of spaced, parallel, vertically positioned arc runner enclosures in the form of slotted tubes with the slots in the two tubes being in adjacent parallel relationship and interconnected by an arc extinguishing passageway I6 of uniform cross sectional area throughout its height. It should be understood that our invention is not limited to this configuration of the arc extinguishing chamber and the following description is concerned with various modiflcations of arc extinguishing chambers of our invention.

Referring now to Figs. 6 and 7, we have illustrated an arc extinguishing chamber 3| comprising the vertical parallel arranged arc runner enclosures including expulsion tubes i3 and I4 enclosed within tubes of magnetic material I8. The slots I5 in tubes I3 and I4 are interconnected by a member 32 which has formed therein an arc extinguishing passageway 33. The arc extinguishing passageway I3 interconnects expulsion tubes i3 and I4 and since these tubes are parallel to each other the length of this arc extinguishing passageway isc-onstant. By length the dimension in the direction of arc length is referred to. However, unlike the arrangements described heretofore. the arc extinguishing passageway Il gradually converges toward the exhaust end of the arc extinguishing chamber in a manner similar to that disclosed and claimed in Traver Patent 2,314,292. granted March 16, 1943, and assigned to the same assignee as the present application. This causes the arc drawn in passageway I6 to be squeezed into more and more intimate contact with the gas evolving insulating material defining arc passageway Il. It should be noted that arc passageway 3l narrows `so that it completely disappears a predetermined distance from the exhaust end of the arc extinguishing chamber 3i as is clearly indicated by the dotted line 34 oi Fig. 6 so that the arc products and exhaust gases must leave through the openings in expulsion tubes i3 and I4.

It will be understood that the arc extinguishing chambers of our invention may be provided with suitable mufilers or the like to further prevent the arc from blowing out to the open air and from re-establishing outside the are extinguishing chamber if this should be necessary.

In Fig. 8 we have illustrated an arc extinguishing chamber I! substantially identical with the are extinguishing chamber of Fig. 1 except that the arc runner enclosures comprising expulsion tubes I3 and I4 are not parallel with each other but are arranged in diverging relationship so that the arc passageway It gradually increases in a direction parallel with the arc drawn between arc runners I1. The corresponding parts of Fig. 8 are designated by the same reference numerals as in the preceding figures. The passageway I6' has been shown as having a uniform dimension in a direction perpendicular to the walls oi' passageway I6' but it should be understood that this passageway might be constructed like the passageway 3s of Figs. 6 and 7.

In Figs. 9 and 10 there is disclosed an arc extinguishing chamber 36 in which the corresponding parts thereof are designated by the same reference numerals as in the preceding figures. In this case the arc runner enclosures comprising expulsion tubes I3 and I4 are arranged in the same manner as in Fig. 8 so as to diverge in a. direction toward the exhaust end of the arc extinguishing chamber. However, the arc moves in a lateral direction in its travel toward the exhaust end of the arc extinguishing chamber, rather than in a vertical direction as in the preceding figures. The arc passageway 31 interconnecting the slots I5 in expulsion tubes Il and I4 is serpentine in configuration in accordance with the arrangement disclosed and claimed in the above mentioned Traver patent. Also the passageway 31 gradually increases in length and decreases in width from the entrance to the exhaust end of the arc extinguishing chamber, as is obvious in comparing the passageway 31 of Fig. 9 with the passageway 31 of Fig. 10 illustrating a sectional view taken on line Iii-II of Fig. 9. If desired, suitable exhaust openings such as 38 may be provided near the exhaust end of the arc extinguishing chamber or arc chute, as is clearly indicated in Fig. 9.

In Fig. 11 there is illustrated still another modification of our invention, in some respects similar to the arc extinguishing chamber of Fig.

- 8. The corresponding parts of Fig. 11 are desigausm? nated by the same reference'numerals asin the preceding figures. The arc e chamber Il otFlg. 11 ditiers from Fig. 8 in that the passageway lll corresponding to passageway It' is somewhat wider in a direction perpendicular to the side walls dening the passageway. Furthermore, this passageway is subdivided into a plurality of passageways by virtue of-insulating barriers or arc splitters 4| arranged in spaced vparallel relationship and supported by means of bolts 42. Barriers Il are also provided with a plurality of openings I3 to interconnect `the parallel are passageways and permit distribution of arrangement disclosed and claimed in the copending application of Joseph W. Seaman, Serial No. 527,913, ii-led March 24, 1944, and assigned'to the same assignee as the present application, now

Y Patent No. 2,429,846, issued Oct. 28, 1947.

It should be understood that when the interrupting chamber of our invention is used to interrupt direct currents one arc runner becomes the cathode and the other arc runner becomes the anode. In such a case it may be desirable tol use tubes of diierent bores and geometry to enhance the performance.

It should be understood that two or more of the arc extinguishing devices described above should be understood that only a single tube might be employed in accordance with our invention.

While we have shown particular embodiments of our invention, it will be understood oi course that we do not wish to be limited thereto since many modiiications may be made, and we, therefore, contemplate by the appended claims to cover all such modiiications as failA within the true spirit and scope of our invention.

What we claim as new and desire to secure by Letters Patent of the United States, is,

1. An arc extinguishing chamber for an electric circuit interrupting device comprising a pair of expulsion tubes of insulating material arranged adjacent one another, means deilning a slot in each tubeextending longitudinally thereof, said tubes being positioned with their slots opposed and vsubstantially coplanar, insulating means for providing between said tubes a longitudinally enclosed passageway interconnecting said slots and having a width materially less than the width of the opening in saidtubes, means for initiating an arc in said passageway, and means `for lcausing the arc to travel along said passageway and into said expulsion tubes for rapid extinguishment of the arc.

2. An arc extinguishing chamber for an electric circuit interrupting device comprising an expulsion tube of insulating material, means dening a narrow slot in said tube extending longitudinally thereof, means for drawing an arc outside of said tube, and a tubular magnetic member around the exterior of said expulsion tube for causing the arc to move into. said tube through said slot tor rapid extinguishment of the arc by the expulsion action of the tube.

3. An are extinguishing chamber for an electric circuit interrupting device comprising an expulsion tube of insulating material, means deiining a slot in said tube extending longitudinally I thereof, means for establishing near one end of said tube an arc between a point within the the arc gases somewhat inaccordance with the tube and a point external thereto. and means for causing said arc to move along said slot in a direction toward the other end of said tube comprising a tubular magnetic member around the exterior of the tube.

4. An arc extinguishing chamber for an electric circuit interrupting device comprising' a cylindrical expulsion tube at least the inner surface of whichv is formed of gas evolving insulating material, meansdeflning a narrow slot in said tube extending longitudinally thereof, means for establishing near one end of said tube an are between a point within said tube and a point external thereto, and a concentric magnetic tube mounted exteriorly of said expulsion tube for causing the arc to move along said slot in a direction toward the other end of the expulsion tube.

5. An arc extinguishing chamber for an electric circuit interrupting device comprising an expulsion tube formed of gas evolving insulating material when subjected to the heat of an electric arc, means dening a narrow slot in said tube extending longitudinally thereof, means for establishing near one end of said tube an arc betweena point within the tube and a point external thereto, and `means comprising a tube of magnetic material surrounding said tube for causing the arc to move along said slot in a direction toward the other end of the tube.

6. An arc extinguishing chamber for an electrio circuit interrupting device comprising an expulsion tube ot insulating material, means defining a narrow slot in said tube extending longitudinally thereof, means for establishing near one end of said tube an are between a point within the tube and a point external thereto, an are runner in said tube, and magnetic means for causing the arc to move along said slot in a direction toward the other end of said tube.

7. An arc extinguishing chamber for an electric circuit interrupting device comprising a pair of expulsion tubes of insulating material arranged adjacent one another in parallel relationship, means deiining a slot in each tube extending longitudinally thereof,.said tubes being positioned with their slots opposed and substantially coplanar. insulating means for providing between said tubes a longitudinally enclosed passageway of uniform cross sectional area interconnecting said slots and having a width materially less than the width of the opening in said tubes, contact means separable in said passageway to draw an arc therein, and means for causing the arc to travel along said passageway and into said expulsion tubes for rapid extinguishment of the arc comprising tubular magnetic members respectively embracing said expulsion tubes and extending longitudinally thereof.

8. An arc extinguishing chamber for an electric circuit interrupting device comprising a pair of expulsion tubes -of insulating material arranged adjacent one another in diverging relationship, means deilning a slot in each tube extending longitudinally thereof, said tubes beingA positioned with their slots opposed and substantially coplanar, insulating means for providing between said tubes a longitudinally enclosed arc passageway interconnecting said slots and having a width materially less than the width of the opening 'in said tubes, means separable in said passageway for drawing an arc therein, and magnetic means for causing the arc to travel along said passageway and into said expulsion tubes for rapid extinguishment ot the arc, the arc increasing in length as it travels along said passageway.

9. An arc extinguishing chamber for an electric circuit interrupting device comprising a pair of vertically positioned expulsion tubes of insulating material arranged adjacent one another in parallel relationship, means de tlning a slot in each tube extending longitudinally thereof, said tubes being positioned with their slots opposed and substantially parallel, means for providing between said tubes a longitudinally enclosed passageway interconnecting said slots and having a width materially less than the width of the openings in said tubes, means for drawing an arc in said passageway, and means for causing the arc to travel upwardly in said passageway and into said expulsion tubes for rapid extinguishing of the arc.

10. An arc extinguishing chamber for an electric circuit interrupting device comprising a pair of expulsion tubes of insulating material arranged adjacent one another in diverging relationship, means defining a slot in each tube extending longitudinally thereof, said tubes being positioned with their slots opposed and substantially coplanar, gas evolving insulating means for providing between said tubes a serpentine passageway interconnecting said slots and having a width materially less than the width of the opening in said tubes, means for drawing an arc in said passageway, and means for causing the arc to travel along said passageway increasing in length and coming into more and more intimate Contact with said gas evolving insulating means to cause rapid extinguishment of the arc.

11. An arc extinguishing chamber for an electric circuit interrupting device comprising a pair of expulsion tubes of insulating material arranged adjacent one another, means defining a slot in each tube extending longitudinally thereof, said tubes being positioned with their slots opposed and substantially coplanar, means for defining between said tubes a longitudinal enclosed passageway interconnecting said slots and having a width materially less than the width of the opening in said tubes, means for drawing an arc in said passageway, means for causing said arc to travel upwardly in said passageway and into said expulsion tubes, and barriers within :aid passageway to divide and cool the arc for rapid extinguishment thereof.

12. An arc extinguishing chamber for an electric circuit interrupting device comprising a pair of expulsion tubes of insulating material arranged adjacent one another, means defining a slot in each tube extending longitudinally thereof, said tubes being positioned with their slots opposed and substantially coplanar, insulating means dening between said tubes a passageway interconnecting said slots, means for drawing an arc in said passageway, and means for causing the arc to travel along said passageway and into .rzaid expulsion tubes for rapid extingulshment of the arc, said passageway being closed at the exhaust end of said arc extinguishing chamber so that the arc gases can exhaust only through said expulsion tubes.

13. An arc extinguishing chamber for an electric circuit interrupting device comprising a pair of expulsion tubes of insulating material arranged adjacent one another, means defining a slot in each tube extending longitudinally thereol', said tubes being positioned with their slots opposed and substantially coplanar, insulating means defining between said tubes a passageway interconnecting said slots, said passageway being longitudinally enclosed and having a width materially less than the width of the opening in said tubes, means for drawing an arc in said passageway, means for causing the arc to travel along said passageway and into said expulsion tubes to cause rapid extinguishment of the are, and means defining a plurality of openings in the insulating means comprising said passageway.

14. An arc extinguishing chamber for an electric circuit interrupting device comprising a pair of expulsion tubes of insulating material arranged adjacent each other, means defining a narrow slot in each tube extending longitudinally thereof, said tubes being positioned with their slots opposed and substantially coplanar, insulating means defining between said tubes a narrow passageway and interconnecting said slots, and means for drawing an arc in said passageway comprising an arc terminal member in each tube terminating against the wall of the tube opposite the slot therein.

l5. An arc extinguishing chamber for an electric circuit interrupting device comprising a pair of expulsion tubes of insulating material arranged adjacent ea-ch other, means defining a narrow slot in each tube extending longitudinally thereof, said tubes being positioned with their slots opposed and substantially coplanar, insulating means defining between said tubes a narrow passageway interconnecting said slots, means -ior drawing an arc in said passageway, and means for causing the arc to travel along said passageway and into said expulsion tubes for rapid extinguishment of the arc comprising magnetic means external to said tubes extending longitudinally thereof and shaped to provide a more intense magnetic blowout action at the slots than in the tubes.

16. An arc extinguishing chamber for an electric circuit interrupting device comprising a pair of expulsion tubes of insulating material arranged adjacent each other, means defining a narrow slot in each tube extending longitudinally thereof, said tubes being positioned with their slots opposed'and substantially coplanar, insulating means defining between said tubes a narrow passageway interconnecting said slots, means for drawing an arc in said passageway comprising an arc terminal member in each tube terminating against the wall of the tube opposite the slot therein, and means for causing the arc to travel along said passageway and into said expulsion tubes for rapid extingulshment of the are comprising a slotted magnetic member for each of said tubes extending longitudinally thereof and shaped to conform to the exterior of said tubes whereby to provide a more intense magneticblowout action at the slots than in the tubes.

NICHOLAS F. ARONE. EUGENE W. BOEHNE.

REFERENCES CITED The following references are of record in the file'of this patent:

' UNITED STATES PATENTS Number

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