US1914137A - Circuit interrupter - Google Patents

Description

June 13, 1933. w. M. LEEDS 1,914,137

CIRCUIT INTERRUPTEH Original Filed Jan. 24. 1931 Fig. 3.

INVENTOR Mh/hrapMLeeas.

ATTEJRNEIY Patented June 13, 193 3 WINTHROP I. LEEDS, F WILKINSIBURG,

PENNSYLVANIA, ASSIGNOR TO WESTING- HOUSE ELECTRIC MANUFACTURING COMPANY, A CORPORATION. OF PENNSYL- VANIA CIRCUIT INTERRUPTER Application filed January 24, 1931, Serial No. 511,005. Renewed April 11,

- My invention relates to circuit interrupters and, more particularly, to circuit breakers of the oil-immersed type in which deionizing structures are provided for extinguishing arcs. This application is a continuation in part of my copending application S. N. 453,909, filed May 20,1930.

An object of my invention is to provide a novel type of arc-extinguishing, structure which shall be very effective and of compact design.

Another object of my invention is to provide means for so directing the streams of i gases expelled from, a pair of deionizing structures that the two streams will not become joined to cause a flash-over between the contacts. This makes it possible to place the deionizing grids closer together and to use a, smaller tank. 9 A further object'of my invention is to provide a deionizing structure in which the arc is initially so drawn in an outwardly flared groove as to reduce the pressure of the gases tending to force the are out of the groove, and to provide amagnetizing member for acting on the are at the point where it is initially drawn. 7

A further object of my invention is to provide a stack of deionizing grids having a slot through which the moving contact is operated I and in which some of the plates, at spaced intervals in the stack, have fla-red vent for cooling and directing the gases that are formed by the arc.

A tfurther object of my invention is to provide a deionizing structure having a narrow groove into which the arc magnetic .means, this groove being so constructed as to allow movement of the arc into it but to oppose movement of the are out of it. This is accomplished by providing a plurality of tapered projections extending 111130 the groove. These projections are placed in staggered relation to the projec- J tions between a plurality of oil-retai 'ng pockets so that it is easier for the arc to be moved in the groove. At the same time, the

staggered projections cause turbulence of the gas to more effectively deionize the are.

. A further object of the invention is to proa wide outwardly is' moved by.

vide elongated oil-retaining pockets, the longest axes of which are transverse to the slot in which the arc is moved. This makes possible the retention of a greater amount of oil for a given length of slot.

These objects and advantages of my invention will be made further apparent from the following description of the accompanying drawing, in which, I

Figure 1 is a sectional view through a cir; cuit breaker embodying my invention, showin the interior parts in elevation,

Fig. 2 is a sectional view through the stack of deionizing plates, taken on the line IIII of Fig. 3,

Fig. 3 is a sectional view on the line TIL-III of Fig. 2,

Fig. 4 is a sectional view on the line IV-IV of Fig. 2, and

Figs. 5, 6, 7 and 8 are plan views showing the individual plates which comprise the deionizing structure.

Referring to Fig. 1, the circuit breaker 10 comprises an oil-tight tank or container 11 which is filled with oil or other insulating liquid 13. Current conductors 15 extend t rough insulating bushings 17 which are secured, by flanged collars 19, to the top ofthe tank 11. The lower end of each of the conductors 15 is provided with a stationary contact member 21. made between the contact meansof a-conducting bar 23 having upstanding tips 25. Conducting bar. 23 is actuatedto open or to close the circuit breaker through operating rod 22 by a suitable mechanism (not shown). p

.A stack of deionizing plates 27 is secured to the end of each of the conductors 15. The deionizing structure is formed by assembling a plurality of plates, as shown in Figs. 5 6, 7 and 8 and comprises a plurality of groups of plates in which .each group comprises a pair of. fiber plates 29 having therebetween an iron plate 31 having a slot which is lined with a lining member 33 of fiber. A plurality of these grou s of plates are spaced apart by plates 35 of ullerboard or other oil-absorbing material. I

The plates, 29 of fibre have a slot 37 ex- Electrical connectlon is members 21 by tending from one edge ofthe plate to the interior thereof. This slot has projections 39 to constrict the passage. The projections 39 have their edges on the side facing the open end of the slot tapered, as at 41, and have their rear edges 42 at right angles to the axis of the slot, so that there will be less resistance to movement of the are into the slot than out of the slot. The outer end 43 of the slot 37 is wider than the inner portion. This provides suflicient room for the entrance of the tips 25 of the conducting bar 23. The slot 47 in iron plate 31 which is used to provide a magnetic field to force the are into the slot, has a similar widened portion 45 at its outer end and a narrowed portion 46 at its inner end. The magnetic field is thus strengthened in the inner portion of the slot where the gas pressure tending to force the are out of the slot is greatest. The fiber lining member 33, which is placed within the slot 47 of plate 31, protects the edges of the iron from the arc. The lining member 33 has a slot 49 similar to the slot 37 in plate 29, with projections 51 having their outwardly facing edges 53 tapered for the same reason as the projections in slot 37. I

Fullerboard plates 35, which are placed between the groups of plates 29, 31 and 33, are provided with slots 55. Oil-retaining pockets 57 are provided for keeping a quantity of oil in intimate contact with the arc as it is moved into the slot. These pockets 57 are of oval shape, with the longer axis of the oval transverse to the axis of the slot. This makes possible the use of a larger number of pockets for a given depth ofslot than would be possible if the longer axis of the pockets were in line with the slot. Oil pockets 57 are separated by projections 63 which have their outer corners 62 rounded and their inner corners 64 square so as to aid movement of the are into the slot and to retard movement of the are out of the slot. One of the outer edges of the slot 55 is cut away at an angle, as at 59. This provides an outwardly tapered vent 61, the axis of which is inclined at an angle to the axis of the slot 55.

\Vhen'the deionizing stacks 27 are assembled on the conducting rods 15. by means of through bolts 16, they are so placed that the outwardly flared vents 61 are inclined to opposite sides of the line between the slots. This.

so directsthegases that are expelled from the slot that the two streams do not come into contact, thus lessening the danger of a flashover between the stationary contacts 21 after the moving contacts 25 have been opened.

As is shown in Fig. 2, which is a section through the assembled stack, the projections 39 on the plates 29 and projections 51 on the plates 33 extend into the groove formed by the aligned slots in the various plates. These projections are so positioned that they extend into the groove in line with the center of the oil-retaining pockets 57. gers the projections 63 on the fullerboard plates 35 and the projections 39 and 51 on the plates 29 and 33 that the arc does not encounter both sets of projections at the same time, as it is moved into the groove, thus lessening the resistance to its movement. At the same time, the staggered positions of the two sets of projections cause turbulence of the gases formed by the are as to give a more effective cooling and deionizing action.

It should also be noted that the moving contact 25 is so drawn into the flared vent 61 that the are is initially drawn into the wid- .ened portion of the groove where the pressure of the gas tending to move the are out of the slot is reduced. At the same time, the arc is initially so drawn within the slot be tween the legs of the magnetic member 31 that it is under the action of a magnetic field to move it into the slot. This construe tion is advantageous in that the arc is initially drawn under control of the magnetic field and, atthe same time, the arc is not subjected to the flow of gas at high velocities,

as would be the case it the arc were drawn in the narrow portion of the groove. As the arc is moved into the slot, it is acted upon by a magnetic field of increased strength, due to the narrowing of the slot at 46. This provides an increased force to move the are as the resistance to its movement is increased because of the higher velocity of the gas and the projections 39, 51 and 63.

The top three groups of fibre plates 29 and 33 shown in Fig. 3 have the ends of slots 43 and 49 closed at 65 and 67, as shown by the dotted lines in Figs. 5 and 8. By having the groove closed at the top, a plurality of vents are formed which cool and deionize the escaping gases formed by the decomposition of the oil by the arc, and movement of the upper end of the are out of the slot is also prevented.

Fromthe above description it is apparent that my invention provides a compact arcextinguishing structure which is most effective in deionizing the are drawn by a circuit interrupter in a minimum of time.

bodiment of my invention, it should be under- While. I have shown and described a specific em- This so stagstood that various modifications may be made 1 and that I am not to be limited except as indicated by the terms of the following claims. j

I claim as my invention;

1-. In an arc-extinguishing structure for acircuit interrupter, means forming a chamber having a vent for the gases formed by the arc, said vent being outwardly flared to one side only of the center line of said chamher.

2. In an arc-extinguishing structure for a circuit interrupter, means having a groove in which the are is formed, portions of one outwardly tions end portion 0 end of said groove at spaced intervals being open and outwardly flared, the axis of said flared portion being inclined at an angle to the axis of said groove.

3. In an arc-extinguishing structure for a circuit interrupter, a stack of plates having slots therein, someof said plates having corresponding ends of their slots open and outwardly flared, the axis of said flared portion being inclined at an angle to the axis of said slot.

4. In an arc-extinguishing structure for a circuit interrupter, a stack of plates having slots therein, some of said plates having corresponding ends of their slots open and outwardly flared, the axis of said flared portion being inclined at an angle to the axis of-said slot, other of said plates, at spaced intervals in said stack, having closed slots.

5. In an arc-extinguishing structure for a circuit interrupter, a stack of plates having slots therein, some of said plates having corresponding ends of their slots open and outwardly flared, the axis of said flared portion being inclined at an angle to the axis of said slot, other of said plates, at spaced intervals in said stack, having slots with open ends of less width than said slots having outwardly flared ends.

6. In a circuit interrupter, a pair of arcextinguishing structures having aligned vents therein, the ends of said vents being flared and having axes inclined to opposite sides of the line between said vents.

7. In a circuit interrupter a pair of arcextinguishing structures each of which has a groove in which the arc is drawn, said groove having portions of its outer'end at spaced intervals outwardly flared to one side only, the said pair of structures having said grooves facing each other, with the outwardly flared portions on opposite sides in each structure.

8. In a circuit interrupter, contacts and a conducting bar for closing the circuit across said contacts, an arcextinguishing structure adjacent to each of said fixed contacts, each of said arc-extinguishing structures having a groove in which the arc is drawn, said grooves being aligned to permit movement of said conducting bar there through, each of said grooves having porat spaced intervals outwardly flared to opposite sides of the line between said grooves.

9. In a circuit interrupter, means forming a grove having portions provided with outwardly flared open ends, a magnetic member having portions extending on each side of said groove and having end portions which aresubstantially parallel, and means for initially drawin an arc in the outwardly flared I said groove and between the a pair of fixed substantially arallel end portions of said magnetic mem er.

10. In an arc-extinguishing structure, a plurality of slotted plates of magnetic material spaced .apart by slotted plates of insulating material, the slots in some of said plates of insulating material being outwardly flared from a point within the slots in said magnetic plates to their outer edge, and

said slots in the plates of insulating material increasing to a width greater than the width of the end portion of the slots in the plates of magnetic material.

11. In an arc-extinguishing structure, a plurality of plates of magnetic material having slots, the end portions of said slots in the plates of magnetic material being of uniform width, and a lurality of plates of insulating material fl aVing slots, ahe end portions of said slots in the plates of insulating material being outwardlyflared beginning at a point within said slots in the plate of magnetic material.

12. In an arc-extinguishing structure, a plurality of plates of magnetic materialhaving slots therein, slotted insulating liners for the edges of the slots in said magnetic plates, and a plurality of slotted material, the end portions of said slots in the plates of insulatin material being of greater width than the en portions of said slots in the insulating liners.

13. In a circuit interrupter, a stack of plates of insulating material having slots therein provided with flared open ends, and a plurality of slotted plates of magnetic material interposed between said insulating plates at spaced intervals, said magnetic plates having portions extending beyond the beginning of said flare in the insulating plates, and means for initially drawing the arc in the flared portion of said insulating plates within the slot in said magnetic plates.

14. An arc-extinguishing structure having a groove therein into which the arc is moved and means along said groove spaced from each other in the direction in which the arc is moved for providing greater resistance to movement of said are out of said groove than into said groove.

15; An arc-extinguishing structure having a groove therein into which the arc is moved, a plurality of projections extending into said groove at spaced points, said PIOJBCUODS being so shaped as to provide less resistance to movement of said arc into said groove than out of said grooveI 16. In an arc-extinguishing structure, a plurality of insulating plates having slots therein, the slots in someof said plates having restricted portions, some of which are staggered in relation to the others' 17. In an arc-extinguishing structure, a groove in which the are is moved, oil pockets along said groove, and projections extend-- plates of insulating flared end portion of the '1n into said groove near the center lines of said oil pockets. 7

18. In an arc-extinguishing structure for a means having a groove therein, and elongated oil pockets having their greatest dimension transverse to said groove.

19. In an arc-extinguishing structure for a circuit interrupter, a plurality of plates of oil-absorbing material, slots in said plates,

and oval oil pockets having their longest axis transverse to said slots 7 20. In an arc-extinguishing structure for .a circuit interrupter, means having a groove in which the arc is formed, portions of one end of said groove at spaced intervals being open and outwardly flared, the axis of said flared portion being inclined at an angle to the axis of said groove and portions of the end of said groove between said outwardly flared portions being of less width than said outwardly flared portions.

21. In an arc-extinguishing structure for a circuit intcrrupter,-means having a groove in which the arc is formed, portions of one end of said groove at spaced intervals being open and outwardly flared, the axis of said flared portion being inclined at an angle to the axis of said groove and portions of the end of said groove between said outwardly flared portions being closed.

22. In an arc-extinguishing structure, a plurality of plates of magnetic material having slots, the end portions of said slots in the plates of magnetic material being of unlform width, and a plurality of plates of insulating material having slots, the end portions of said slots in the plates of insulating material being outwardly flared beginning at a point within said slots in the plates of magnetic material, and the axis of said outwardly slots in the plates of insulating material being at an angle to the axis of the slot.

23. In an arc-extinguishing structure for a circuit interrupter, means having a groove therein for the arc, one end of said groove extending to an outenedgg of said arc-exting uishing structure,'and said groove being of greater width at said end at spaced intervals along the length thereof than at intermediate points between said spaced intervals.

24. In an arc-extinguishing structure .for a circuit interrupter, means having a groove therein for the arc, one end of said groove extending to an outer edge of said arc-extinguishing structure, and said groove having portions which increase in width toward said end at spaced intervals along the length thereof to a width which is greater than the width of said groove at intermediate, points between said spaced intervals.

25. In an arc-extinguishing structure for a circuit interrupter, means having a groove therein for'the arc, one end of said groove extending to an outer edge of said arc-explates of insulating material having aligne tinguishing structure, and said groove having portions which increase in width toward said end at spaced intervals along the length thereof to a width which is greater; than the width of said groove at intermediate points between said spaced intervals, magnetic means having a slot therein for moving the are in said groove, and said widened end portions beginning to increase in width at a point within said slot in the magnetic means.

26. An arc-extinguishing structure for a circuit interrupter including a plurality of plates of insulating material having aligned slots therein extending from an outer edge of each plate to the interior thereof, the outof insulating material for moving the arc in the slots thereof, and the outer end of the slots in some of said plates of insulating material increasing in width beginning at a point within the slots in said plates of magnetic material to a width greater than the width of the corresponding end portions of the slots in the other of said plates of insulating material, and said plates having the slots with end portions of increasing width being positioned at intervals between said other plates. I

28. In an arc-extinguishing structure for a circuit interrupter, means having a groove therein for the arc, one end of said groove extending to an outer edge of said arc-extinguishing structure, and said groove having portions which increase in width toward said end at spaced intervals along the length main portion of the groove.

29. An arc-extinguishing structure for a circuit interrupter including a plurality of slotstherein extending from an outer edge of each plate to the interior thereof, the outer end of said slots in some of said plates being wider than the end of the slots 1n the other plates, said plates having the slots with the wider ends being positioned at intervals between said other plates, and the axis of said widened end portions of the slots bein inclined at an angle to the main portion 0 the slots.

" the slots c plurality of slotted plates of magnetic material positioned between some of said plates of insulating material for moving the arc in the slots thereof, and the outer end of the 10 slots in some of said terial increasing in point within the slots width greater than thethe corresponding end port-ions of other of said plates of innet1c material to'a -width of in the plates of insulating mawidth beginning at a in said plates of magsulatingmaterial, ,and said plates having the slots with end portions of increasing width being positioned at intervals between said other plates,

and having portions at 0 spaced intervals along the interior of said slot of greater widt portions of the slots h than the corresponding in said other plates forming pockets along said slots and along which the arc is moved by said magnetic plates. 31. Ina circuit interrupter, means for causing a pair of arcs, an arc extinguishing chamber for each of sa1d arcs, each Of Sflld arc extinguishing chambers having lateral venting means therefro of fluid out of said of fluid being directed away m, means causing a flow venting means, saidflow between said arc extinguishing chambers.

trical terminal members, a movable bridg member for completing between said termi tinguishing structure for each including means of inminal members,

11 a circuit interrupter, a pair of elecing the electrical circuit nal members, an are exeach of said tersulating material having a passage there- 0 through in which the arc separation of said bridging of said terminal members means adjacent th acted upon by the said chambers, pair of chambers b each other.

formed upon the member from one is caused to play, e are path which when are causes fluid pressure in each ofthe chambers, means Venting said fluid laterally through and the venting means in said the side of each of eing directed away from 33. In a circuit interrupter, a pairof electrical terminal tinguishing chambe ed on each of said in the side of each chambers for a members, a pair of are exrs, one of which is mountterminal members, a slot of said are extinguishing portion of the length thereof, a bridging'memb er having each end thereof movable in the slot in the side, of one of said are extinguishing chambers for drawing an arc in each for each of sald ch chamber, venting means ambers, and (each of said venting means being directed away from the other.

member for comple ting the electrical circuit from the space said bridging member from one of said terminal members is caused to play, means adjacent the arc path which when acted upon by the arc causes fluid pressure in each of the chambers, and means venting each of said chambers to opposite sides of the line between said terminal members.

35. In a circuit interrupter, a pair of electrical terminal members, a movable bridging member for completing the electrical circuit between said terminal members, an arc extinguishing structure for each of said terminal members, each including means of insulating material having a passage therethrough in which the are formed upon the separation of said bridging member from one of said terminal nfembers is caused to play, meansadjacent the arc path which when acted upon by the arc causes fluid pressure. in each of the chambers, a slot in the side of each ofsaid chambers for a portion of the length thereof and in which said bridging member is movable, and lateral vents for said chambers directed away from the space between said chambers.

36. In a circuit interrupter, means for causing a pair of arcs, an arc extinguishing chamber for each of said arcs, each of said are extinguishing chambers including a stack of continguous plates of insulating material having a passage therethrough, each of said are extinguishing chambers having lateral venting means therefrom, means causing a flow of fluid out of said venting means, said flow of fluid being directed away from the space between said are extinguishing chambers.

37. In a circuit interrupter, means for causing a pair of arcs, an arc extinguishing chamber for each of said arcs, each of said are extinguishing structures including a stack of contiguous plates of insulating material, some of said which the arc plays, and the apertures in some of said plates being elongated forming vents to the outside of said chamber, and the outer end of some of said vents being directed away from the space between said chambers.

38. In a circuit interrupter, means for causing a pair of arcs, an arc extinguishing chamber for each of saidarcs, each of said are extinguishing structures including a stack of plates having apertures therein in contiguous plates of insulating material, some of said plates having apertures therein in which the arc plays, and the apertures in some of said plates being elongated forming vents to the outside of said chamber, and the outer end of some of said vents being directed away from the space between said chambers, and other of said platespositioned at spaced intervals in said stack being unvented.

, 39. In an arc-extinguishing structure for a circuit interrupter, means forming a chamber having a vent for the gases formed by thearc, said vent having an end portion the axis of which is inclined to one side only of the center line of said chamber.

40. In an arc-extinguishing structure for a circuit interrupter, a stack of-plates having slots therein, some of said plates having corresponding ends of their slots open and the axis of said end portion being inclined at an angle to the axis of said slot.

41. In an arc-extinguishing structure for a circuit interrupter, a stack of plates having slots therein, some of said plates having corresponding ends of their slots open and the axis of said end portion being inclined at an angle to the axis of said slot, other of said plates, at spaced intervals in said stack, having closed slots.

42. In a circuit interrupter, a pair of arcextinguishing structures having aligned vents therein, the ends of said vents having'axes inclined to opposite sides of the line between said vents.

43. In a circuit interrupter, a pair of arceXtinguishing structures each of which has a groove in which the arc is drawn, the said pair of structures having said grooves facing each other, with the end portions inclined to opposite sides in each structure.

In testimony whereof, I have hereunto subscribed my name this 23rd day of January,

WINTHROP M. LEEDS.

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