US2147512A - Circuit breaker - Google Patents

Description

T. ASANUMA CIRCUTT BREAKER Feb. 14, 1939.

2 sheets-sheet 1 Original Filed March 1, 1935 Fig 2 Fig 1 T. ASANUMA CIRCUIT BREAKER Feb. 14, 1939.

Drignal Filed March 1, 1935 2 Sheets-Sheet 2 GII Patented Feb. 14,1939

UNITED -sTAT'Es CIRCUIT BREAKER Toshi Arsanuma, Toshima-ku, Tokyo, Japan Application March 1, 1935, Serial No. 8,963. Re-

newed January 5, 1939.

7 Claims.

This inventionrelates to improvements in electric oil switches of high tension, the object being safe' the under pressure which forces the arc incident to' the contact break across the edges of iixed plates, together with mechanical switch-closing means which is'tensioned for switch-closing operation in the breaking of the circuit and released at will for the switch-closing function.

The accompanying drawings being illustrationof the invention: Y

Figure 1 is a view in vertical section,`partly in elevation, of the improved circuit breaker,the contacts being shownclosed.

Figure 2 is a similar view, the contacts being shown in their positions occupied in' the initial separation of such contacts.

Figure 3 is a sectional detail, partly in elevation. of the means for supporting the pump cylinder at the required height.

Figure 4 is a view similar to Figure 2, showing the contacts separated to their maximum extent.

Figure 5 is a top plan view of the circuit breaker.

Figure 6 is a section on line A-A of Figure 4.

Figure 7 is a section on line B-B of Figure 4.

'I'he improved circuit breaker comprises a bowl- .like lower section I, an intermediate section 24 removably secured upon the upper end of the lower section, and a casing 2l secured upon the upper end of the intermediate section. 'Ihe xed contacts are housed within the lower body section I, the movable contactsare guided in the intermediate section 24, and the operating means for the movable contacts is mounted in the upper In Japan March 2,

Il) which depend through 'the opening' in the I bottom plate II and within each of which tubes there is arranged a terminal of the conductor leads controlled by the switch.

Mounted upon the support I2' and connected to the upper ends ofthe tubes I0 is a circular disk I3 having an upstanding flange, the inner surface of which is slightly convergent, downwardly. The conductor terminals, indicated at |01', are threaded into elements I3 which rest upon the upper surface of the disk I3 on opposite sides of an upstanding partition 3'- carried by said support.

Mounted in the elements I3" are the respective xed contacts constituting oval-shaped bodies 3 in each of which are arranged threev movable elements including circular heads 4, screen-like depending bodies 6 and springs l maintaining the heads 4 normally in positions slightly above the pole-pieces 3, the movement of the heads being limited by stops 5.

The lower ends 8 of the pole-piecesl 3 are of course in electrical contact with the extensions of the conductor terminals I0', andas the movable elements 4 of the pole-pieces vof contacts permit convenient renewal without the necessity of renewing the entire pole-piece and reduces the area of actual contactunder separation of the contacts to reduce the arc.

A tubular director I4, which' is of insulating material, is formed to encircle the pole-pieces of xed contacts, the lower end of thisY director being frictionally held against the inner surface of the upstanding ange .of the disk I3 and the upper surface of the director terminating on a plane materially above that of the llxed contacts in `an annular ring I4', the margin of the interior openingof which is in line with the outer margin of the xed contacts.

Below the upper annular ring, the director is formed with diametrically opposed openings I5, the lower margins of which are in the plane of the xed contacts, and Within these openings are supported cutting blades I6 of rigid insulating material. The blades I6 are materially less in thickness than they vertical dimension of the openings I5, so that the openings I5 provide a space above and below each plate or blade. The

` blades I6 extend outwardly beyond the margin of the director I4 and their inner edges conform tothe shape of that of the xedlcontacts 3as clearly shown in Figure 7.

The partitionn3 extends upwardly to the lower the cutting blades "Las be clearirom I- jigures 1, 2 and 4.

An insulating lining' I1 is` supported at its upper end upon an outstanding ledge at' the upper end of the. body- I, the arrangement being such that the lining depends withinthe body to provide a-narrowspacebetweenthe body and lining. The lower end of the liningis open to provide communication from the space 2 within' the lining and within which 'the xed contacts and connecting parts are mounted and the space I8 between the lining and body. The space I8.

is of restricted cross-sectional area and is provided to define a lengthy path'f'or the downward flow of the oiland a restriction in the speed of that'ow.

The immgfn is -interi'eriy thickened et theV upper end to provideA awall having a central opening to receive'and support a thimble I9 in axial alignment with'the director I4, with such wall reduced to provide with the 'intermediate member 2 4 a chamber 2 I which, through the medium of a passage V2li passing through the thick-` ened wall of the lining, is in'communication with the annular space I8 between the lining I1 and body I.

Ihe intermediate section 24 is bolted to the body'I o form an upper wall for the chamber 2 I, with the upstandingouter wall of such intermediatesection formedwith an annular channel 22 closed at the upper end and open at the lower end to the chamber 2|. Thus, the annular 'space 22 is in open communication with the space 2 of the lining I1 in -whichthe iixed contactsare mounted through the medium `of the chamber 2|, passage 20 and space I8. A

The space 22 is formed with relief openings closed by plugs 23 set at various .heights of the space 22,'whereby, in filling the circuit breaker, theheight of the oil in jthelspac'e 22 may be determined by dislodging the appropriate plug 23 and wherein, after the relnsertion of the plug.'

J the air is trappedin thespace 2 2above the level Y of the oil for a purpose whichwill later appear..

upper end of the sleeve valve to limit the'upper l The bottom of the intermediate member is centrally formedwitha guide sleeve 25 which extends above and below thel bottom which coaxial with the director I4, that portion of the guide sleeve below the bottom interfitting with the thimble`A I9. to form an inner wall of the vchamber-2| and at the same time a non-leaking connection with the thimble., A sleeve valve 43 is movably mounted in the guide sleeve 25, the upper end of the guide sleeve beingformed with an annular recess to receive a projection onthe and lower movements' of the sleeve valve relative f wardly.

The guide sleeve Y25 is formed with a series oij vertically. extending inwardly projecting spaced ribs defining between them a series of passages which are fully open at the upper ends and which, at their lowerends, communicate through ports 42 with the interior space 2 when the sleeve valve' is at its lower limit, -as indicated inFlgure 1 of the drawings. An annular rib closes the lower ends of these' oil spaces against direct ow downslidabiy ined within `the sleeve valve and eentacting with the inner edges of the ribs of the sleeve valve is a pump cylinder 38 formed at its --vlower end as an annular ring and above such ring as spacedconcentric -wallsthe outer Aone 38' of which is'longer than the inner one 38".

An insulating ring 39 andcontact ring 48 are secured to the ring portion at the lower end ofthe cylinder 38,"the contact ring l4i! being connected to the lower edge of vthe-insulating ring 33 and the latter connected to theloweredge of the ring "portion of the cylinder, with both the insulating ring 3 9 and .the contact ring 40 ofthe same externall'y'and internally dimensioned' proportions as and aligned with the pump cylinder 38.

'I'he outer sin-face of theouter wall 38' of the pump cylinder is provided at the upper end with an annular rib 48 and-at a point below the upper Y 'end with a second annular rib 45,.the upper rib 1 46 servingas a n ieansto locate the position of the pump cylinder through mechanism to -be later described, while the lower rib 45 is so posi-f tioned thatin the downward movement of the pump cylinder, such rib `45 will engage and depress the sleeve valve 43.

The open upper end .ofthe upper casing 2111s provided with apressure cylinder 32 which is of less diameter than vthe casing 21 and provided with a'n annular outstanding ange to provide for securing and centering the pressure cylinder 'in place; The lower end 'of the pressure cylinder is -formed'with aninwardly depressed pocket 3| `open tothe interior of the cylinder and connected by a pipe 38 leadingthrough the wall of the casing 21, with the pocket providing a trap for water and lubricant leaking across the piston and p rovidingforthe discharge from such trap to prevent such materials entering the insulating oil in the circuit breaker.

A differential piston 35 is mountedwithin the pressure cylinder 32 with suitable packing, the piston being extended as a hollow body 35' which iits within the inner `wall of the cylln'der 38 and is provided at its lower end witha packing 31 to seal the juncture between the piston and cylinder. A spiral spring-36 underlies the project- 'it will be noted that it passes through the upper ring member I 4' of the director I4 between the inner edges of the plate I6 and into engagement .with the xed contacts. In this position, the lower end of the conductor ring 40 beyond those -portions directly'engaging the contacts is supported in the. opening I5 of the director wholly free o f underlyingcontact and providing faces which, as will belat'er explained, may be reached by the oil under pressure and' incident to such pressure be forced to move upwardly to break the contacts.

vIt will be noted particularly from Figure 7 .that the --so-called xed contacts' occupy but a portion of the circular area, leaving a space :I: between `the ends of these contacts. This space provides an uninterrupted area'which directly underlies the lower end of the conductor ring 4l and which is exposed to the pressure of the oil in the' operation of the device to create an upward pressure on the conductor ring to breakvthe contacts.

Withinthe casing 21 is placed an operator including a rack 49 and cooperating pinion 48. The hollowend of the rod 50 forming an extension of the rackv 49 is formed with two diametrically Vop posed axial slits 5I, each with a shoulder 53 out- .but heldagainst longitudinal movement.

ward. Through the shoulders Il the rack Il hangs'on a spiral spring l2 which bears on the bottom of a hole in the crown of the cylindrical body 21 and on the top of'the hollow end ofthe rod l asleeve rests slidably in the same hole by a shoulder formation at the upper end on which sleeve is mounted a spiral spring 58 stronger than the spring 52. An open-bottom spring case is screwed at its lower end into the hole in the flange of press cylinder 32, compressing both the springs l2 and 58 until the outside shoulder of said sleeve lcomes in contact on the shoulder in the hole in the cover. lThrough the opening centrally bored in the crown of the spring case a hollow spindle il extends, mounted for rotation by disc head Si The lower endof spindle 55 projects into-the hollow end of the rod 5|! and has two stops Il on-the opposite sides immediately above the top ofthe rod 5|). Through-the spindle and knob loosely extends a testing rod 51 screwed at the lower end into the rod lli,` with its upper end projected a l little above the disc head 5l.

l'ns

In a position of stops 54, as shown in Figures 1, 2 and 3, the rod and rack being only under the influence of the weak spring S2, may be easily moved downwardly but not upwardly, as the top of the rod is in contact with the stops 5l on the spindle 55, and thus the pinion is always turnable counterclockwise but not clockwise. In consequence, the rim 48 at the upper end of the outer wall o f the pump cylinder, in the upward movement, passes above the pinion l2, but following the beginning of its downward movement the pump cylinder stops, being limited by engaging with the pinion not rotatable clockwise, and thus the pump cylinder is supported in the required height. This condition may be changed at will by turning the knob 56 and bringing the stops 54 in line with the slits 5|, allowing the spring 3l, contracted as shown in Figure 4, to compress the spring 52, to drive up the rod and rack, and to turn the pinion clockwise. The position of the testing `rod is thus an indication and shows the engagement of the cylinder with the'pinion.

'Ihere are an oil inlet 33 with tap in the top and an opening 29 with tap in the side of the oil chamber 28 which communicate with the switch chamber 2 by the passages 42 and M provided in the lowest position ofsleeve valve l2, and in the outer wall of the middle section 24 are provided a series of openings 23 bored in steps and screwed taps.

Freeing one of the openings 23 and openings 29 and 23, through the latter, the charge of oil poured in the oil c hamber 2l flowing by the passages and 42 fills in the chamber 2, annular space i8 and through the openings 20, the annular space 2l and the lower portion of the annular space 22, and flows out of the open hole 22 `which is then closed. The walls and surface of is as follows:

In Figure 1, when theA operating medium, for instance compressed air, has been admitted into the cylinder 32, the compressed air drives the plunger3linwardly,aswellasthebodyofoii within the pump cylinder downwardly. As the free portion of the contact ring 4l is encircled by the tubular director Il, the oil is compelled to act upon the underside of said portion and Hto lift the cylinder 22, separating the bridging contact 4l from the fixed contacts 3 and auxiliaries l.

In t-he parting of contact faces of electrodes, the communication between the interior of pump cylinder and switch chamber is established above the surfaces of the poles through the openings I5, as shown in Figure 2. At the same time the powerful oil pump causes the two oppositelydirected high velocity blasts of oil across the arcs formed between the said separating contact faces, and through the openings wherein the cutting blades are placed and into the chamber 2. 'Iherefore by means of the openings, the arcs are forced on to the cutting edges of the blades and cut oi! by them. The extinguishing of the arc is certain' and practically instantaneous in everyV instance. In order to make the extinguishing action more eilicient, the pressure of the oil blasts are continuously increased during the operation, incident to the fact that the increase of oil in the chamber 2 lifts the sleeve valve 42 covering the openings 42 and cutting of! the passages to the upper chamber 2l. In the consequent compressing of the ai-r in the top of the chamber 22,

y and raising the pressure on the oil and air, the

rise in pressure is proportional to the intensity of the spring 3S between the cylinder and plunger in its contraction..

Each flux of oil, carrying the arcs and bubbles peculiar to each terminal, in the same'side with it, in passing across the parting contact faces, is directed against and over the rigid edges of the blades and thereby the arcs and bubbles drawn between contacts will be cut'or sheared into two Y parts which are cooled and compressed between the edges and the continually flowing oil. Thus, the arcs have been in practically every instance extinguished instantaneously and surely. But if this is not instantly eifective, it takes place at the next instant, for the arcs at once will be folded into w-shapes, hanging the middles on the edges and having the ends on the contact faces, by the ilow of oil from both sides of the cutting blades at the edges of which the flow of oil separates and is carried away, being made more slender and weaker and being beaten on the same points and so weakened on the edges by the increased oil momentum, will thus be cut off immediately after the arcshave come in contact with the edges. Until the end of stroke of plunger has been reached, the excess oil is pumped out for cooling. When the under surface of the cylinder passes above the upper edges of the ungrooved portion Il of the sleeve valve, the exit ducts 44 become uncovered, the chambers 2 and 28 being in communication and the oil and gases 4pass v'out through the passage from chamber 2 into the chamber 22 due to the expansion of the air hitherto compressed in the chamber 22, balancing the pressures. Gases escape by the freed opening 32 or piping 3l from the chamber 22 into the I v The pump cylinder and sleeve valve will then lose their supporting forces and the sleeve valve at once drops but the pump cylinder comes to rest on the tooth of the pinion by the rim 4l, while the heated oil and gases in the chamber 2 are displaced with the cold oil from the oil chamber above. The engagement may be released whenever required by turning the knob Il and putting oii the mesh oi the stops on tubeiwith the top of the rod 5l). i

When the pump cylinder is freed from the pim1 l ion, it is by the action of spring 36v driven into the chamber 2.' This puts the oilunderpressure, compressing the-air into the chamber 22, at the same time closing the chamber 2 with the sleeve valve lifted and then an amount of the movement will bring thesupporting pressure of the' oil under the ring conductor equal to the tension of springthe former increasing but the latter decreasing-preventing the further movementof the cylinder. But immediately after the pinionl has been released, the exhaust of the cylinder is opened, allowing the same spring to drive the plungerupwards. During the movement, the plunger sucks the o'il from the chamber 2 into the cylinder, forming a partial vacuum in the former.

The actions of the partial vacuum as well Vas the spring drive the cylinder against the electric 'poles until the ring conductor'comes in contact with them and the circuit is closed, affording a quick and non-arcing closing. The vacuum in the chamber is illed through the f passages 44 and permitted by dropping of l to contain a body of oil, a relatively ilxed elec trode in the casing, a relatively movable electrode in 'the casing, manually operable means tending to move the electrodes into'ci'rcuit closing relation, means for creating pressure on the body of oil to cause' the oil to move the movableI elec,- trode from circuiting contact with the iixed electrode, the movement of the movable contact tensioning. the mechanical means for operating said contact toward circuit closing relation, means to hold the movable contact in that open relation following operation of the oil under pressure and against the iniiuence of the mechanical closing means, a tubular director surrounding the. electrodes and formed with diametrically opposed Passages substantially in the plane of the contacts, and ian arc .breaking plate xed in each of said passages `andvspaced from the upper and lower walls thereof.

A2. A- circuit breaker including a lower casing,

an upper casing, a valve sleeve= controlling com.-

munication between the casings, the casings being designed 4to containavbody of oil, a fixed electrode in the lower casing, a movable electrode moving through the upper casing into circuiting contact with the iixed electrode, means in the lower casing for creating pressure on the bod-y of oil in the upper casing .to cause the oil to lift the movable electrode and the sleeve valve to cut ofi communication between the upper and lower casings, means immediately above the iixed electrodefor directing the oil under pressure laterally of the electrode when the movable electrode is in non-circuiting ,relation to thereby direct the arc laterally oi thefelectrode, aspring for moving the movable electrode into circuitingrelation with the xed electrode, said 'spring being tensioned in the oil pressure movement of the movable electrode, manually controlled means 'for holding the movable electrode in non-circuit-- fui ing positionfwith the spring under tension, and meansiffor causing the springs on release of the K anemia manually controlled means to move' the movable electrode. toward the -iixed electrode and create oil pressure in the lower chamber, the move- 3. .A circuit breaker including an upper casing, l

a lower casing, a movable sleeve valve controlling communication between the casings, a movable electrode movable through the upper casing, a fixed cooperating electrode mounted in the lower casing, the upper and lower casings being designed to contain a body of oil,.means in the lower casing for creating pressure upon the sur# face of the body of oil in the upper casing to subject the movable electrode to a pressure-compelling movement away from the xed electrode,

the oil under pressure flowing between the elec.

trodes when the movable .electrode is in noncontacting relation with the xed electrode, an element encircling the iixed electrode and iormed with passages to direct the oil under pressure in opposite directions laterallyioi thel electrodes after the movable'electrode is moved to a non-` circuit closin'g relation with the iixed electrode, an'd a iixed element dividing each lpassage into upper and lower openings and itself providing an arc-breaking element, the upper and lower openings providing for the passage of oil, under pressure into the lower casing.

4. A circuit breaker including an upper casing, a lower casing, a movable sleeve valve controlling communication between the casings, a mov# able electrode movable'through the upper casing, a xed cooperating electrode mounted in the lewe: casing, the-upper and lower casings being designed to contain a body of oil, means in the` lower casing for creating pressure upon the surface of lthebodyoi oil in the upper casing to subject the movable electrode to a pressure-com-v pelling movement away from the fixed electrode,

the oil under pressure iiowing between the elec- .the movable electrode is moved to a non-circuit closing relation withI the iixed electrode, and a fixed element dividing each passage into upper and lower openings and itself providing an arcbreaking element, the upper and lower openings providingfor the passage of oil under pressure into the lower casing, mechanical means for moving the movable electrode toward circuiting relation. with the xed electrode, said means cref ating a pressure on the oil in the vlower casing during such movement, and a by-pass in thelower casing forming a restricted lengthened channel communicating with an automatic pressure means at the top and with the lower casing af the lower end.

5. A circuit breaker including a lower casing, an upper casing, fixed electrodes in th lower casing, a movable electrode inthe upper casing, said movablel electrode including a pump cylinder. a sleeve valve encircling the pump cylinder and providing communication between the upper and lower casings, means on the pump cylinder to operate the sleeve valve in the circuit closing movement of the movable electrode, a spring for Y for creating pressure on the oil to lift the movable electrode, a projection on the pump cylinder,

manually, controlled means carried bythe upper` casing to engage the projection and hold the movable electrode in non-circuiting relation with the fixed electrodes, and means on the pump cylinder to operate the sleeve valve to establish communication between the casings in the movement of the movable electrode under the influence 0f the spring. h

6. A circuit breaker including a lower casing,

an upper casing, xed electrodes in the lower Y casing, a movable electrode in the upper casing, said movable electrode including a pump cylinder, a sleeve valve encircling the pump cylinder and providing communication between the upper and lower casings, means .on the pump cylinder to operate the sleeve valve in the circuit closing Imovement of the movable electrode, a spring for moving the movable electrode into circuit closing relation with the ired electrodes, the upper and lower casings being designed to contain a body of oil, a plunger operative within the pump cylinder for creating pressure on the oil to lift the movable electrode, a projection on the pump cylinder, manually controlled means carried by the upper casing to engage the projection and hold the movable electrode in non-circuiting relation with the fixed electrodes, means on the pump cylinder to operate the sleeve v alvefto establish communication between the casings in the movement of the movable electrode under the inuence of the spring, a tubular director surrounding the iixed electrodes, and meansv carried by the tubular director and open to the iiow of oil under pressure to break the arc in the .separation of the electrodes.

'7. A circuit breaker including a lower casing, an upper casing, fixed electrodos in the lower casing, a movable electrode in the uppervcasing,"

said movable electrode including a pump cylinder, a sleeve valve encircling the pump cylinder and providingcommunication between the upper and lower casings, means on the pump cylinder to operate the sleeve valve in the circuit closing movement of the movable electrode, a spring for moving the movable electrode into circuit closing relation with the iixed electrode, the upper and lower casings being designed to contain a body of oil, a plunger operative within the pump cylinder for creating pressure on the oil to lift the movable electrode, a projection on the pump cylinder, manually controlled means carried by the upper casing to engage tlie projection and hold the movable electrode in non-circuiting relation with the xed electrodes, means on the pump cylinder to operate the sleeve valve to establish communication between the casings in the movement of the movable electrode under the influence of the spring, a tubular director surrounding the fixed electrodes, and means carried by the tubular director and open to the iiow of oil under pressure to break the arc in the separation of the electrodes, said means compelling a division in the oil ilow into distinct streams relative to the means.

his

TOSHI X ASANUMA.

' mark Witness to mark:

N. S. KAsAWA.

Images