US1998941A

US1998941A - Electric circuit breaker

Info

Publication number: US1998941A
Application number: US703570A
Authority: US
Inventors: Perino Jules
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 1933-12-22
Filing date: 1933-12-22
Publication date: 1935-04-23
Anticipated expiration: 1952-04-23
Also published as: GB427876A

Description

April 23, 1935. J. PERlNo ELECTRIC CIRCUIT BREAKER Filed Dec. 22, 1955 Inventor:

Jules F M110,

`His Atborneg.

Patented AApr. 23, `1935 e. y 'n l UNITED STATES rPATlszNT orrics Jules Perino, Philadelphia, Pa., assigner to General Electric Company, a corporation of New 'Yorkf Application December 2 2, 1933, Serial No. 103,570

4 claims. (ci. zoo-15o) 'y f i My invention relates to electric circuit breakable contacts 2 and 3 as by inner insulating cyl- 1 ers, more particularly to electric circuit breakinders I0 and II ntted to the inner wall of the 5 ers of the so-called oil-blast explosion-chamber pot 1 and by an insulating throat bushing .I2 'gf type wherein an initial pressure generating arc having a central ilared opening I3 for receiving 5 is ,formed for causing the circuit-interrupting oil the movable contact l." The insulating cylin- 5 blast, and has for its principal object the provision derS lilk and ll Serve t niOunt and pOSitiOn en of simplified and improved contact structure for insulating diSk il 0n which the intermediate eOncircuit breakers of the aforesaid type. tact 2 is mounted. The insulating disk Il is pro- My invention/will be more fully set forth in Vided With apertures I4' extending tliiOugli the 10 the renewing description referring to the acsame and interconnecting upperk and lower por- 10 companying drawing, and the features of novelty tiOnS 0f the eXplO'SlQn Chamber fOr apurpOSe preS- which characterize my invention wiii be pointed ently described. The intermediate contact 2 is out with particularity in the claims annexed to pOSitiOned in a Centrally disposed aperture l5 in and forming a part oi this specication. the insulating disk.

c Referring more particularly to the drawing, 'I'he throat bushing I2 is secured in position by 1.5 the single iigure thereof is anelevational view in a Spacing nut I6 and lock nut I1 which are cross section of one pole o! a circuit breaker of threaded directly 0n the insulating bushing. The the oil-blast explosion-chamber type embodying insulating Cylinder ll extends as at Il Over the the present invention, inner edge ofthe explosion pot throat flange 9 y The explosion chamber contact structure i1- and a suitable gasket I8 is positioned between the 20 lustrated constitutes one pole of a circuit breaker byerlinging iiange 0f the threat bushing l2 and of a, well-known type wherein two similar explothe insulation II. The exterior ot the pot 1 is sion chambercontact structures, comprising the sultalily insulated es by Sleeve-like insulating two poles of the switch, are immersed in an insu- Cylinder i9 SuppOrted by an insulating flange 20 lating liquid as cil dnd are interconnected in which is in turn secured to the pot 1 by a nut 2|. 25 l closed circuit position by a conducting bridging The upper butt eentt l eOlnpriSeS a eylinmember which is vertically movable within the drical guide pOltiOn 22 Which i5 Slidably mounted insulating liquid with respect, i-,o lche explosion on a bolt 23 secured to the adapter 5 and resilchamber structure. In the present instance the iently biased. aS by Coil Spring 2l, towards the expicsicn chamber ccntnci, structure comprises lower position illustrated. The guide bo1t'23 is 30 a butt contact I, an intermediate or floating conprOvided With an insulating Sleeve 25 and downtact 2 and a. mcvnb1e tubular contact 3 which is ward movement of the butt contact I is limited carried by the aforesaid bridging member. In the by a SliOulder 22' 0f the guide Dertien 22 which closed circuit position the 'intermediate contact iS arranged to abut the corresponding Shoulder 2 is in butt contact engagement with center-,ts 23' at the lower end of the bolt 23. The actual 35 l and 3 so as to complete the circuit between the Contact making and arcing surface of the ybutt lead-in conductor 4 and the bridging member, contact I is formed by a replaceable cap 26 se- The explosion chamber structure comprises an Cured aS by Screw-threaded engagement at 2l t0 adapter 5 and a connecting member 6 to which the portion 22 and composed oi a suitable conthe adapter is connected so that the lend-in ccnducting and arc-'resisting metal. The electrical 40 ductor. l is electr-lenny connected to the adapter 5 .connection between the butt contact I and the and rigidly mounted with respect thereto. The adapter 5 is provided by a plurality of exible adapter 5 in turn is connected to and supports conductors 28 which directly conduct current a steel cylindrical member 1 comprising an exfrom theadapter 5 to the contact AI thereby proplosion chamber pot. The pot 1, which is ccntecting the biasing spring 24 from overheating. f..

structed to withstand high bursting pressures, is The intermediate contact 2 is simply and eblnconnected at its upper inner edge to the adapter paetly arranged Within the ekplOSiOn chamber as by screw-threaded engagement indicated at-a and, as previously described, is insulated with and at its lower edge is provided with an inwardrespect to the pot 1 by the insulating disk il 5o ly extending annular flange l forming generally which likewise serves as a support for the inter- 50 the throat or exhaust of the explosion chamber mediate contact. The intermediate contact comthrough which the movable tubular contact 2 is prisesja short tubular member 29 of conducting operated. material having connected thereto at opposite The explosion chamber pot 1 is suitably insuends butt contact portions I0 and II for coasting lated with respect tothe intermediate and movwith the contacts I and I., respectively. The 55 butt-contact portions 30 and 3| are conveniently formed by disk-like portions having threaded extensions or studs 3U' and 3l respectively arranged to engage corresponding threaded portions in the interior ot the tube 29 as illustrated. When so secured in position, the contact portions are locked with respect to tube 29 by pins 32.

A coil spring 33 seated at one end in a recess 34 in the insulating disk I4 and at its other end in a retainer 35 normally biases the intermediate contact to the lower position illustrated where it is held against further movement by the engagement of the contact portion 30 with the insulating disk I4. An insulating sleeve 33 secured to the disk I4 surrounds and protects the spring 33. As in the previous instance, the contact portions 30 and 3|, and likewise the removable contact tip 3' of the tubular contact, are composed of.

suitable arc-resisting contact metal.

Referring more particularly to the operation oi' the device, the closing of the circuit is effected by elevation of the tn bular contact 3 which rst engages contact portion3| oi the intermediate contact and elevates the intermediate contact against the bias of spring 33 into engagement with butt contact I. Overtravel of the bridging member is provided for by reason of the resiliently mounted butt contact I.

Opening of the circuit is eiected by lowering o! the tubular contact 3, the contacts continuing in following engagement until the butt contact I reaches its lower limit of travel, at which time separation of the butt contact and intermediate contact 2 occurs. The resulting arc within the explosion chamber, which is illled with oil or other suitable insulating liquid, generates a high pressure within the chamber by reason of decomposition of some of thevinsulating liquid by the arc. Continued lowering of the contact3 results in separation of the same from the intermediate contact when the latter contact reaches its lower limit of travel, resulting in a second arc in series with the rst or pressure generating are between the contacts 2 and 3. As the tubular contact 3 passes through the throat of the explosion chamber the aforesaid pressure causes a blast of oil from the chamber through the second arc and into the tubular contact to exhaust extericrly of the explosion chamber thereby extinguishing said arc and interrupting the circuit.

After circuit interruption the explosion chamber rells with oil from the main circuit breaker tank, the adapter 5, which forms the top wall of the explosion chamber, being provided with an aperture 31 for permitting escape of accumulated gas and serving to limit excessive pressure. The accumulation of gas generated within the explosion chamber is localized to a considerable extent at the upper part of the explosion chamber by reason of the insulating disk I4, the apertures I4 serving generally to transmit pressure to the lower part of the chamber so that a blast of oil rather than gas is obtained for interruption oi' the arc.

It should be understood that my invention is not limited to speciilc Idetails of construction and arrangement thereof herein illustrated, and that changes and modincations may occur to one skilled in the art without departing from the spirit of my invention.

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

1. An electric circuit breaker of the oil-blast explosion-chamber type comprising relatively movable contacts including an intermediate contact, said intermediate contact comprising a tubular conducting member, insulating structure in which said tubular member is slidably mounted, and butt contact arcing portions detachably coneected to the opposite ends of said tubular mem- 2. An electric circuit breaker ot the oil-blast explosion-chamber type comprising relatively .movable contacts including an intermediate contact, said intermediate contact comprising a tubular conducting member, and disk-like butt contact portions at opposite ends ot said tubular member having screw-threadedl stud portions extending into and engaging said tubular member for electrically and mechanically connecting said butt contact portions thereto.

3. An electric circuit breaker of the oil-blast explosion-chamber type comprising relatively movable contacts including an intermediate contact, means forming an explosion chamber in which said contacts coact, an insulating disk mounted in said chamber and supporting said intermediate contact, said intermediate contact comprising a cylindrical conducting member slidably mounted in said insulating disk and disklike butt contact portions secured and electrical- 1y connected to opposite ends of said cylindrical member, and means biasing said cylindrical member in a direction longitudinally thereof, one of said disk-like butt contact portions coacting with said insulating disk for limiting movement of said intermediate contact.

4. An electric circuit breaker of the oil-blast explosion-chamber type comprising relatively movable contacts including an intermediate contact, means forming an explosion chamber in which said contacts coact, an insulating disk disposed withln said chamber and dividing the same into upper and lower portions. said insulating disk having apertures therein including an aperture for receiving said intermediate contact, said intermediate contact comprising a cylindrical conducting member slidably mounted in said lastnamed aperture, disk-like butt contact portions secured and electrically connected to the opposite ends o! said cylindrical member. a spring interposed between said insulating disk and one of said butt contact portions for biasing said intermediate contact in a direction longitudinally thereof, the other of said butt contact portions engaging said insulating disk for limiting movement of said intermediate contact, and an insulating sleeve depending from Isaid insulating disk and surrounding said spring.

JULES PERINO.