US2625627A

US2625627A - High-voltage contactor system

Info

Publication number: US2625627A
Application number: US735634A
Authority: US
Inventors: Frederick Y Grepe
Original assignee: Canadian Controllers Ltd
Current assignee: Canadian Controllers Ltd
Priority date: 1947-02-27
Filing date: 1947-03-19
Publication date: 1953-01-13
Anticipated expiration: 1970-01-13

Description

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A Qa 1 M MBV y 442590) A TTOR/V Y Jan. 13, 1953 F. Y. GRI-:PE

HIGH-VOLTAGE CONTACTOR SYSTEM 4 Sheets-Sheet 5 Filed March 19, 1947 INVENToR. y. 9445 Arme/VFY I aguda/114K Jan. 13, 1953 F, Y, GREPE 2,625,622?

HIGH-VOLTAGE CONTACTOR SYSTEM Filed March 19, 1947 4 Smets-Sheet 4 GMAGWL? ATTR/VEY I N VEN TOR.

Patented Jan. 13, 1953 UNITED STATES PATENT. OFFICE y 'I aszastzrww .I

HIGH-VOLTAGE coNg'rAcroR sysrsivr Frederick Y. Grape, Toronto, Ontario, Canada, as- Y signor to Canadian Controllers, Limited, Toronto, Ontario, Canada y applicati@ March 19, 1947, serial No. 135,634

In Canada February Z7, 1947 My invention relates broadly to high voltage contactors and more particularly to a construction of high voltage contactor having means for magnetically blowing out arcs at the contacts.

One of the objects of my invention is to provide a construction of high voltage contactor having means associated with the contactor for utilizing the gases formed at the contacts in assisting in the extinguishing of the arc.

Another object of my invention is to provide a construction of high voltage contactor system including an effective arrangement of arc runners associated with the contacts for assisting in the extinguishing of the arc and the splitting of the arc into a multiplicity of parts for subsequent dissipation.

Still another object of my invention is to provide an improved method and construction of apparatus for effectively damping the arc formed at high Voltage contactors.

Another object of my invention is to provide yan improved construction of magnetic circuit for facilitating Ithe blowing out of arcs formed at high voltage contacts and displacing the arc through an arc splitter.

A further object of my invention is to provide an arrangement of stack or chimney associated with high voltage contacts with runners extending upwardly through the stack or chimney from the contacts for removing the arc from the contacts and rapidly dissipatingthe arc through the stack or chimney.

Still another object of my invention is to provide a high voltage contactor system in which the opening of the contacts is automatically accompanied by the release of a jet of compressed gas directed transversely to the formed arc which assists in removing the arc from the contacts for dissipation through associated arc runners.

Still another object of my invention is to provide a construction of chimney or stack associated with the magnetic blowout system adjacent high voltage contacts where the chimney or stack provides a support for the resistive element of a damping circuit which becomes effective as the arc moves towards the top of the stack or chimney.

Other and further objects of my invention reside in the improved construction of arc splitter, magnetic blowout system and associated runners in a stack or chimney as set forth more fully in the specification hereinafter following by reference to the accompanying drawings in which:

Figure l is a front elevational View of the improved high voltage contactor of my invention;

, 2 Fig. 2 is a vertical sectional view taken substantially on line 2-2 of Fig. 1, with certain of the parts illustrated in side elevation; Fig. 3 is a vertical view through the magnetic blowout system, illustrating in side elevation the relative arrangement of contacts, arc runners, and the magnetic pole pieces of the magnetic blowout system; Fig. 4 is a top plan view of the magnetic blowout system of my invention; Fig. 5 is a vertical sectional view of the magnetic blowout control winding taken substantially on line 5-5 of Fig, 3; and, Fig. 6 is a schematic and diagrammatic circuit outlay illustrating the principles of the arc dissipating system of my invention.A

Referring to the' drawings in detail reference character I designates a main panel of insulation material arranged to support the high voltage contactors, the operator for the high voltage contactors and the associated magnetic blowout system. An arc chamber 2 formed from insulation material is supported by the rear face of the main panel I. The 4arc chamber 2 is apertured at the bottom thereof for the passage of a verthe panel I as will be v arcing tip or runner 4 which extends toward the iront wall of the arcchamber 2. A stationary contact Sis supported with respect to the rear of panel I on a standard 6 in alignment with the movable contact 3. Terminating adjacent the stationary contact 5, but disposed in spacial relation thereto,I provide a rear arc runner I which extends vertically through the annular opening 8u in the insulated top section 8 of the arc chamber 2 and substantially half way up the insulated stack or chimney formed from cylindrical or tubular insulating material shown at I0. The stack or chimney I0 is secured to the upwardly extending annular portion 8b of the top section 8 by suitable means such as screws Ia.

The stack or chimney I0 extends vertically from the arc chamber 2 for a substantial distance above the arc chamber 2 and supports on the inner wall thereof in a position diametrically opposite the position of the rear arc runner 1, a front arc runner II. The front arc runner II extends interiorly of the entire height of the stack I0 and terminates at its upper end in a terminal I6. The tubular stack IIJ serves as a housing for a vertically extending aro splitter 30. The arc splitter 30 comprises a multiplicity of spacially related parallel electrically

conductive plates

3a, 30h and 3|lc disposed in the stack or chimney IIl intermediate the rear arc runner l and the front arc runner II. The electrically conductive plates 30a, 30h and 33C are electrically" insulated from each other by insulators 30d and 33e located adjacent opposite ends of the plates so that the plates serve as spaced electrodes capable of splitting or dividing the arc.

The exterior of the stack or-chirnneyy I0 carries adjacent the upper end thereof a flange or ring member I4 formed from' insulation mate--4 rial which is forced and cemented upon thefout'v side of the stack or chimney I0. This iiange I4 serves as a support for the commencementofA the winding I5 consisting of high resistancewire such as Nichrome wire which connects at its lower end to a terminal I8 carried by a band I-Sa' which encircles the winding of` resistance wire I5. The upper end ofi the winding? of? resistance wire- I5 isconnec't'ed'toa terminal I1 carried by'band I'Ia which encircles the upper end of the winding: I5. In order't'o' accommodate thewinding I5 of the stack or chimney I is suitablyA grooved at Ib which allows the high resistance wire to be retained" on they exterior thereof and provides a suicient shoulderait each end to form abutment means for' the? bands' I'I and I8a for thereby insuring" a sturdyV permanent construction. The terminal I of the front arc runner I'I connects to theterminal; I'T of the highv resistance winding I5. Terminal I8 at the lower end of the high resistanc'ewinding' I5' connects to the* terminal I9 suppo'rted by the insulated panel I. Terminal I9 connects through an insulated conductor with the terminalZIi carriedby insulated panel I. Terminal 20 extends through panel I and provides a connection for eXible-'lead 2| which connects to the vertically movable contact 3f.

The magnetic blowout system includes a spool of insulation material which I have designated generally at 22 which supports the multiple winding. 24 of the magnetic blowout system; The insulated spool 22 includes the magnetic core 29 which is secured' by means of bolt 23 between the laminated pole pieces 3I` forming the magnetic blowout cheeks or ears. The securing bolt 23 isv supported at opposite ends in the laminated winding 26 on the blowout is of a heavy gauge wire of a few turnsto be consistent with the load which the' breaker will carry and to keep normal temperatures. Winding 2B has a relatively small number of ampere turns. The second winding 'cn the blowout system consists of as many turns asv desired and of a smaller size wire to create a strong eld for the moment of interruption.

' Winding 25 has a relatively large number of ampere'turns. As the second winding is not in series with the load itself a light wire can be used and a proportionately larger number of turns in keeping with space and cost. The

blowout windings

25 and 26 are connected in a manner that the heavy winding 26 of a few turns remains in series with the load when breaker is in the closed position and the second winding 25, through the medium of the arc as a connecting link, energizes the second winding 25 for the period when the breaker opens so that the

windings

25 and 26 of the blowout system 24 are in series with each other during the period when the breaker opens, and so create a strong n'eld when it is most needed.

The movable contacts 3 are each supported by an. insulated bridge 32. The individual movable contacts 3 are resiliently supported with respect to. the bridge 32: b'y means of coil springs 3a disposed` within. the sleeve 3b which supports the contact 3f andl between the end of the internal socketlc in sleeve 3b and the head 3d of the member. 3e. which is mounted on the bridge arm 32. The relative movement of the sleeve 3b with res'pect' to the member 3e is limited by pin 3f carried by member 3e'- projecting through slots 3g in sleeve member 3b'. TheV flexible connection 2 Ii c'onnectsto thev sleeve' member 3b as shown for carrying the high voltage to the contact 3. The lower arcing tip or runner ll moves up and down with the contact 3.

The arm 32' has connected therewith two or moreV a-ir pistons 3-3 which operate in air cylinders 34 which are connected through air blast tubes 35 with nozzles 36 directed at the gap betweencontacts 3- and 5'Y for delivering a blast of air between the contacts 3V andl 5 as they separate. This. action isl automatic due to the. dropvgravity actionof the bridge 32. A puff of air is delivered precisely at the junction of contacts 3 and 5 where the arc is initiated. tending to displace the. arc to the runners d and l.

The operator which operates the. bridge 32 is represented schematically in the form of a solenoid winding 39 operating armature 40 with respect to the pole pieces 4I of. the magnetic core structure 42 withwhich the solenoid winding 39 is associated.

The operation of the control system is rapid for upon energization of solenoid winding 39 armature 40 is attracted- -by magnetic pole pieces 4I ofthe magnetic system 42 and. air pistons 33 move upwardly in air cylinders 34 without. appreciable drag or inertia as air is free to move backwardly through nozzles 36 and. pipes 35 to the air cylinders 34 thereby preventing the setting up of a vacuum. Nevertheless a strong puif of air is delivered at the contacts when the bridge 32 gravitates upon., deenergizationv of solenoid winding 39.

rllhe stack. or chimney constituted by tubular member I0 connected with. the top of the arc chamber 2- serves as an expansion chamber for the gases rising from the arc chamber 2.

Ils'o provide

expansion chambers

31 and 33 in the form of annular recesses provided in arc chamber 2 at the position of entry of sleeve member 3b into arc chamber 2 so that movable contact 3 is free to move vertically while gases may expand into the

annular expansion chambers

31 and 38.

The magnetic blowout system which includes the laminated magnetic pole pieces, cheeks or ears 3l is shaped to extend a substantial distance upwardly on diametrically opposite sides of the stack or chimney I0 for maintaining magnetic flux for directing the arc upwardly through the arc splitter 30 and facilitating the blowing out of the arc. The arc is drawn between contacts 3 and 5 as contact 3 retracts. The eld produced by heavy gauge winding 26 lifts the arc from accada? contact 5 to runnery 1 and from contact 3 to runner 4 assisted by the puff of compressed air from nozzle 36. The arc then persists

be-tween runners

4 and 1. Y'llhe arc having reached runner 'I immediately switches in the multi-turn fine wire winding'25 of the blowout system in series so producing an intense concentration of flux. yThis causes the arc to advance very rapidlyon up runner 1 and eventually spills over across to run ner I I. This then produces two arcs, one between

runners

4 and 1, the main Varc, and another smaller arc between runners 1 and l I. The two arcs are effectively in parallel.

The smaller arc acts as a dischargeresistor across the main arc and so damps out the high peakvoltages which appear across the contacta The main'ai'c will also build up'Vv a pressure Vin the karcing chamber 2 which Vwill tendV to rblast the aro up the chimney-like tube I0. At an appropriate moment the main arc is extinguished leaving the small arc tobe blown vertically upwardly through the tube through the arc splitter 3l), and eventually extinguished. i o

:The current in the small arcis kept down to a predetermined value by virtue of the resistor I5 -inu series. Resistor I5 and the arc which isv itself a resistor constitutes a damper across the main arc. i v

invention. Moreover, I realize that changes may be made inthe details of construction of the contact system and associated are chamber, the stack connected therewith and the arc splitter arranged 1n the stack, and while I-have described my invention'in one ofy its preferred embodiments I desire that it be understood and modications may be made andv that I intend no limitations upon my inventori except as may be imposed by the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent of the'United States is as follows:

l. Ina high voltage contacter system, a setof relatively movable circuit closing and opening contacts, a walled arc pressure chamber enclosing said contacts, and having a restricted outlet in a chamber wall, arc runners adjacent said contacts, a free vent open at the top constitutingr a chimney projecting upwardly from said pressure chamber, in communication with the chamber through the outlet, one of said arc runners extending yvertically upward from the arc pressure chamber through said vent and a coacting arc runner in said vent in a position interiorly thereof diametrically opposite said last mentioned arc runner, whereby the are is' forced to follow a predetermined path upwardly through said vent under the action of a blast resulting from an arc formed in said arc pressure chamber.

2. Ina high'voltage contacter system, `a set of relatively movable circuit closing and opening contacts, a walled arc pressure chamber enclosing said contacts, and having a restrictedoutlet in a chamber wall, arc runners adjacent said contacts, a free vent vopen at the top constituting a chimney projecting upwardly from said arc pressure chamber,- in communication with-the cham-ber through the outlet, one of said arc runners extending ver-tically upward through said vent, a coacting arc runner in said vent in a position interiorly thereof diametrically opposite said last mentioned arc runner and a magnetic blowout system having pole piecesextending on diametrically opposite sides of said vent and for a distance substantially above said arcV pressure chamber and adjacent said arc runners, whereby the arc-is forced into and upwardly through the vent by the action of a blast resulting from an arc in said pressure chamber and by kthe action of magnetic ux between the pole pieces.

3. In a high voltage contacter system, a set o relatively movable circuit closing and opening contacts, a walled arc pressure chamber enclosing said contactsand having a restrictedoutlet in the vtop thereof, arc runners adjacent said contacts, a chimney extending upwardly from the chamber yin communication therewith through the outlet, said chimney being open at the top and forming "a free vent, one of said are runners extending from the chamber through the outlet and upwardly through the chimney, a coacting arc runner in saidv chimney in a position interiorly thereof diametricallyvoppositesaid last ymentioned arc runner and an arc splitter disposed in said chimney intermediate the arc runners'therein, whereby the arc is forced to follow a-predetermined path upwardly through said chimney under the `action of a blast resulting from an arc formed in said arc pressure chamber, and through said arc splitter and through the open top of said chimney.

4. In a high voltage contacter system, a set of relatively movable circuit closing and opening contacts, a walled aro pressure .chamber enclosing said contacts, and having a restricted outlet in the top thereof, are runners adjacent said contacts, a Walled chimney extending upwardly from the chamber in communication therewith through the outlet, said chimney being open at the top and forming a free vent, one of said arc runners extending from the chambei` through the outlet and upwardly through the chimney, a coacting arc runner in said chimney in a position interiorly thereof diametrically opposite said last mentioned arc runner, a magnet `having pole pieces extending on opposite sides of said arc pressure chamber and opposite sides of said chimney and extending upwardly toa position adjacent said arc runners and an arc splittepdisposed within said chimney between said arc runners, whereby the 4arc is forced into and upwardly through the chimney and through the arc splitter and through the free vent formed by said chimney by the action of a blast resulting from an arc in the pressure chamber and by thevaction of magnetic flux between the pole pieces. f

5. In ya high voltage contacter system, a set of relatively movable circuit closing and opening contacts, an arc pressure chamber venclosing said contacts, a restricted orifice at the top thereof, arc runners adjacent ysaid contacts, a stack formed from insulation material and extending upwardly from the Vrestrictedoriiice of said arc pressure -chambenandterminating at the top thereof in a free vent, one of said arc runners extending vertically upwardlyirom said,A chamber through said stack anda coacting arc runner disposed Within said. stack in a position diametrically opposite said last mentioned arc runner 6. In a high voltage contacter systema set of relatively movable circuit closing and opening contacts, an arc pressure chamber enclosing said contacts, arc runners adjacent said contacts, a stacl; formed from insulation material and extending upwardly from said arc pressure chamber and open at the top for forming a free vent, one of said arc runners being disposed adjacent-one of said contacts in arc-gap relation thereto and extending vertically upwardly from said chamber through said stack and a coacting arc runner disposed'within said stack in a position diametrically opposites-aid last mentioned arc runner, a magnetic blowout system comprising pole pieces ex- .ternally of said arc chamber and said stack, disposed so thatthe magnetic ux from said pole pieces4 moves the arc from the contacts in the chamber to the runners and through the stack on the runners, and through said free vent and a resistive damping circuit extending between one of said arc runners and one of said contacts.

7. In a high voltage contacter system, a set of relatively movable circuit closing and opening contacts, an are pressure chamber closed at the bottom and the sides thereof enclosing said contacts, arc runners `adjacent said contacts, said chamber having a restricted opening in the top thereof, a chimney of insulation material extending upwardly from the restricted opening in the top of said arc chamber, one of said arc runners extending vertically upward from said chamber through the openingr and through said chimney, a coacting arc runner in said chimney in a position interiorly thereof diametrically opposite said last mentioned arc runner and an arc splitter disposed` within said chimney and intermediateV the arc runners therein, said arc splitter comprising a multiplicity of electrically conductive plates extending longitudinally of the chimney and insulated one from another.

8. In a high voltage contactor system, a set of relatively movable circuit closing and opening contacts, an arc pressure chamber enclosing said contacts and having a restricted outlet, arc runners adjacent said contacts, one of said arc runners being disposed in arc gap relation with one of said contacts, a chimney of insulationmaterial extendingupwardly from said arc chamber, said last mentioned arc runner extending vertically upward from said chamber through the outlet and through said chimney, a coacting arc runner in said chimney in a position interiorly thereof diametrically opposite said last mentioned arc runner and in air gap relation thereto, an arc splitter disposed within said chimney and intermediate the arc runners therein, said arc splitter comprising a multiplicity of electrically conductive plates insulated one from another and an arc damping circuit connected between one of said runners and one of said contacts.

9. In a high voltage contactor system, a set of relatively movable circuit closing and opening contacts disposed in substantially vertical alignment, an arc pressure chamber enclosing said contacts, a chimney of insulation material extending upwardly from said arc pressure chamber and open at the top to provide a free vent, arc runners adjacent said contacts, one of said runners being conductively connnected with one of said contacts and the other of said runners being disposed in arc gap relation to the other of said contacts in the chimney, said last mentioned arc runner extending vertically upward from said chamber through said chimney, and a coacting arc runner in said chimney in a position interiorly thereof. diametrically opposite said last mentioned arc runner.

l0. In a high voltage contactor system, a load circuit, a set of relatively movable circuit closing and opening contacts, an arc pressure chamber enclosing said contacts, a free vent open at the top constituting a chimney projecting upwardly from said arc pressure chamber, an arc runner extending vertically upward from within the chamber through said chimney, a coacting arc runner in said chimney in a position interiorly thereof diametrically opposite said last mentioned arc runner, anda magnetic blowout system including a pair of magnetic pole pieces extendingv on opposite sidesof said arc chamber, said chimney, and the arc runners therein, and an electromagneticv exciting winding associated with said magnetic pole pieces, said winding including a pair of sections, one of said sections being in series with the load circuit and with said contacts and the pair of said sections being in series with each other and with the load circuit and with the arc runners.

11. In a high voltage contacter system, a set of relatively movable circuit closing and opening contacts, an arc pressure chamber enclosing said contacts, a free vent open at the top constituting a chimney projecting upwardly from said arc pressure chamber, a first arc runner extending vertically upward from said chamber through said vent, a second arc runner in said vent in a position interiorly` thereof diametrically opposite said first arc runner, a third arc runner connected to one of said contacts in the chamber, and a resistance unit connected between the second arc runner and the third arc runner.

12. In a high voltage contacter system, a set of relatively movable circuit closing and opening contacts, an arc pressure chamber enclosing said contacts, a free vent open at the top constituting a chimney projecting upwardly from said arc pressure chamber, an are runner extending vertically upward from said chamber through said vent, a coacting arc runner in said vent in a position interiorly thereof diametrically opposite saidrlast mentioned arc runner and a resistance unit supported adjacent to the upper end of said vent, said unit having one end thereof connected between said last mentioned arc runner and one of said contacts.

13. In a high voltage contactor system, a panel of insulation material, an arc pressure chamber mounted on said panel, a xed contact extending through said panel and projecting into said arc pressure chamber, a movable contact disposed in the bottom of said arc pressure chamber and movable into circuit closing and opening position y with respect to said fixed contact, a load circuit,

a free vent chimney open at the top constituting a chimney projecting upwardly from said arc pressure chamber, an arc runner extending vertically upward from said chamber through said vent, a coacting arc runner in said vent disposed in a position interiorly thereof diametrically opposite said las-t mentioned arc runner, a magnetic blowout system comprising a pair of magnetic pole pieces extending on opposite sides of said arc chamber and extending upwardly for a substantial distance along said vent and on opposite sides of the arc runners therein, an electromagnetic system coupled with said magnetic pole pieces. said electromagnetic system including a pair of. windings, one of said windings connected in the load circuit in series with theY contacts, the

pair of windings connected in the load circuit in series with each other and in series with said arc runners.

14. In a high voltage contacter system, a load circuit, a set of relatively movable circuit closing and opening contacts, an arc pressure chamber enclosing said contacts, arc runners adjacent said contacts, a free vent open at the top constituting a chimney projecting upwardly from said arc pressure chamber, one of said arc runners extending vertically upwardly from said arc pressure chamber and into said vent, the other of said arc runners being disposed in said vent and extending vertically upward through said vent beyond the upper end of the aforesaid arc runner, a magnetic blowout system comprising a pair of magnetic pole pieces extending on opposite sides of said arc pressure chamber, said contacts, said vent and the areJ runners in said vent, and an electromagnetic exciting system comprising a pair of windings one of said windings having a greater number of turns than the other, the one containing the smaller number of turns being connnected in series with the load circuit and with the contacts, and the winding having a greater number of turns being connected in series with the load circuit, the other winding and the arc runners.

15. In a high Voltage circuit breaker, a walled arc-chamber; a stationary Contact in the chamber; a movable contact operable to engage and disengage the stationary contact by operating means passing through a chamber wall; an upn right chimney extending above the chamber; a

restricted outlet through a wall of the chamber communicating with the chimney; a blowout magnet comprising pole pieces at opposite sides of the chamber exteriorly thereof; .a winding in two parts for energizing the pole pieces; a iirst arc runner having a lower end portion in the chamber and adjacent the stationary contact, and extending through the outlet and upwardly along the inside of the chimney; a second arc runner connected to the movable contact, extending laterally therefrom and under the lower end portion of the nrst arc runner; a third arc runner having a lower end portion adjacent the lower end portion of the first arc runner and extending upwardly along the inside of the chimney and spaced transversely of the chimney from the rst arc runner; the magnet pole pieces having 3 and cause it to transfer to the hrst and 10 upright extensions adjacent opposite sides of the chimney and exteriorly thereof; a resistance unit connected to an upper portion of the third arc runner; arc splitting barriers supported in chimney between the iirst and third arc runners therein; the said parts arranged so that when an arc is drawn between the contacts in the chamber magnetic iiux between the pole pieces will propel it to transfer it to the nrst and second arc runner, and gas pd ure in caused by the arc and exhausting suo.- antial velocity through the restricted outlet and upwardly through the chimney combined with propulsion by the magnetic i'iux, will elevate the arc third are runners and move upwardly through the chimney and be lcooled by the arc splitting barrier, and extinguished; and circuit connectie for causing current in fthe circuit-to-be-broien to in series through one part of the magnet winding and. through the arc drawn the contacts; and for causing current in the circuit-to-bebroken to now in series through both. parts of Ithe winding and to the first arc runner and through the arc to the third arc runner and through the resistance unit when the arc has transferred to the rst and third runners.

FREDERICK Y. GREPE.

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

UNITED STATES PATENTS v Number Name Date 1,055,850 Von Zweigbergk Mar. 11, 1913 1,563,833 Christensen Dec. l, 1925 1,751,205 Hellmund Mar. 18, 1930 1,784,760 Slepian Dec. 9, 1930 1,904,463 Hilliard Apr. 13, 1933 1,963,643 Brainard June 19, 1934 2,240,233 Thommen Apr. 29, 1941 2,293,513 Linde Aug. 13, 1942 2,345,724 Baker et a1 Apr. 4, 1944 2,353,729 `Tensen July 18, 1944 FOREIGN PATENTS Number Country Date 116,015 Switzerland Aug. 16, 1926 335,917 Germany Apr. 16, 1921 556,524 Germany Aug. 10, 1932 860,510 France Sept. 30, 1940