US1127996A - Electric switch. - Google Patents

Description

P. V. HUNTER.

ELECTRIC SWITCH.

APPLICATION FILED MAY 6, 1913.

1,127,996. wanted Feb. 9, 1915 INVENTUE Toall whom it may concern A 'msurrnn sTnTns PATENT OFFICE.-

rnrmr Vassar. 31mm, or NEWGASTLE-UiONTYNE; ENGLAND- EIIECTRIG Be it known that I, PHILIP VASSAR Hun :rnn,

' residingat. 41 Coquet Terrace, Heaton, New" circuitv is broken and arcing. takes place) castle-upon-Tyne, in the countyof Northumberland, England, have invented new and useful Improvements in Electric Switches,. of which the following is a specification.

It is known practice to -,m ake electric switches with a number of breaks (that is to say, places where there are pairs ofconi tact polnts or surfaces between which the arrangedin series; and in (irder to attenuate or lengthen the arcs formed so as rapidly to quench these arcs, it is known practice to .employ what is termed a mag netic blow-out, .the usual form being a coil placed in series with the circuit.

In my invention I employ contact points or surfaces at which the circuit is to be broken in series but instead of employing a' magneticblow-out as is usual I arrange these contact points or surfaces. in such manner that thearcs formed upon separation of the points or surfaces will be parallel or nearly so with one another and close together or in arc-extinguishing proximity,

the. current flowing in opposite directions in each arc of a pair of arcs. By this means each arc of a pair will repel the other and an attenuating efiect and,

arcs will be obtained.

My inventionis, illustrated by the accompanying drawings, in which,

v Figures I and II illustrate a simple case of my invention where the repulsion is be-- quenching of the tween two arcs. Fig. III illustrates a case in which the repulsion is between 'an'1'-.zarc and a'conductor; Fig. IV shows a case 1n whichtha conductors in circuit with the arcs-are arranged so ;a s.toreinforce the re pellant action ployment v Fig; illustrates the em? aflies to increase the attenuae.

* tion-of the arcs. Figs. VI and VIIIHHSV;

. or two'arcs and two conductors may be arj rangedso as to securethe desired-repellant .tacts designed to .trate cases in which the arcs are crossed,.

and Fig. VIII illustrates how four arcs action;

In ri aji and II, I illustrate a simple case of myinvention inwhich 1, flare con-' tact points or surfaces attached to rods 5, 6

and 1n fixedposition. 3,4 are movable con:

contacts 1 and 2 respectively. Thesemovablev contacts ,3, 4 are in' electrical connec- Speciflcation of letters Patent.

make contact with the fixed Patentetl Feb. 9,1915.

- Application Meditayfi, 1913. tenan -165,741.-

tion with one another andadapted to be pulled away from .the fixed contacts when circuit isto be broken. In Fig. I, I show the pairs of contacts (1 and 3', and 2 and 4 respectively) in their closed position while in Fig. II, I show them in their separated position, it being assumed that they have i just been pulled apart for the purpose of breaking circuit. The direction of the cufbe in opposite directions. Z, 8 (Fig. II)

represent the two arcs formed on the open ing of the circuit and it will be seen that these repel one another as shown, the direction of therep'ellin'g forces being to separate them and blow them out and the proximity of the are being suflicient to effect this result. l

My invention is particularly applicable to switching apparatus'in large-power-distributing systems at high potentials and it will be seen that in spite of this fact I-place the two arcs-in close proximity to one another whereas in electrical practice hitherto one would naturally consider that they should be put widely apart. My reason for placing themin' close proximity to one another is to obtain as strong a repelling cf feet between the two arcs as possible so that they may be 'quickly extinguished. In

other words,I place them in arc-extinguishng proximity and I further make the dis'-* pair of are striking'tertance! between a minals less than the length of each are, that is, less than the maximum separationof the ioo material which I sometimes find it con- -venient 'tojemploy. It is not anessential feature. of-iny'invention and when'l'l employ it I preferto i'nake'it as fusedsilica..- 4 y the figures just described- I show only one pair of arcs but when desired I may of what is known employ'two or more pairs of arcs.

= 1 do. not confine my. invention to themain contacts-off switching apparatus but may apply it -to auxiliary contacts'placed either 65 rent is shown by the arrows and is seen to inseries or in parallel with the main contactsand the number of pairs of contacts connected after the manner of tion may be considerable.

I have hereinbefore referred to pairs of arcs each one of a pair repelling'the other my' haven-- arc of a pair. It'w1ll be seen however that the current in a conductor is equivalent to the current of the' arc and that therefore a conductor could be substituted for one of the arcs and without departing from 'the' I spirit of my invention. This is illustrated in Fig. III where it will be seen that in- :Zead of having 'two breaks I have only e break and that the are at that break will be parallel or 'nearlypaiallel with the conductor' 10 which is the equivalent of and substitute for the arc 7 shown in Fig. 11. s

In some cases I so arrangethe conductors in circuit with the arcs as to. reinforce or increase the repellent action. Thus "I may make the leads on one or both sides of the are long and. parallel and so as in them-- selves to exert arepel-lent action. This'is illustrated in Fig-1V. L Here it will be seen that the conductors 11, 12-o n either side of are 7 are placed parallel withthe conductors 12, 13 on either side of'the are 8 and with the currents flowifigin the directions shown by the arrows. The "effect of this is to intensify the-blow-outaction as this will depend, in each arc, not-only upon the magnetic field produced .by'theopposite" are but also upo that set 5 up by the conductors shown.

- may increase the attenuation of the arcs by placing baflies oflinsulatingfireproof ma-' terial in. the course of the arcs themselves;

This is diagrammatically illustrated in Fig. V where 15, 15 show the baflies and 16, 16 the'hypothetical'course' of the baflled arcs.

' I have hereinbefore spoken of 'the -twc' arcs vas being parallelor nearlyjso, but in.

some cases I may depart from this practice. Thus in one form' I contemplate so arranging the arcs that' they cross one another. This is shown in, its simplest diagrammatic expression in Fig. VI where it.

will beseen that contact 3 is assumed to I have 1 been separated from contact-1- and contact from contact 2 so that-the arcs pass between 1 and 3, and 2 and 4 respec tively. Fig. illustrates 'this crossed arcarrangement in connection-. with the separator- 9, this separator being 'inthe present instance in the form of a fiat sheet.

i f The contacts '3 and 4 are .'in this case-the movable ones and they are assumed to have been drawn apart from their corresponding .fixed centacts' in the directions of the arrows The use of full and 'dotted' lines in this case illustrates that separation takes place in two planes one 'on each side of the separator. l'-.In the caseoi 'avsingle'arc and a en desired I" a repellent. conductor-'1 may also obtain the crossing effect and thisI can do either by partingrthe arc contactslin a rectilinealmanner as shownat one are in Fig. VII

or'by separating the contacts in a; helical. direction. In one way of doing this the .cen- I ter of angular movement offthei novable contact or contacts would .be around an axis coincident with that of therepellent conductor assuming thelatter to be straight.

It will of coursebe understood that the shape of the gsepara'tor will depend upon circumstances. Thus when theseparation takes place in .a helical direction the sepavrator may take 'a cylindrical or prismatic to m.'- Or-yand this. applies to most forms,

the separator may take the form of a tube surrounding or' partly surrounding the space occupied by one of .the arcs or sur- '8 rounding or partly surrounding a re elle t conductor. a

-- The actual mechanism by means of which the contact-surfacesare separated forms no partotmy present invention; It will be seen that by applying the forces which draw out or attenuate theiqa'rcs to the-arcs themselves (which have puacticall'y no mass and therefore {but littleinertia) very rapid acceleration in breaking the circuits maybe obtained. a I

I think it probable that in electric switches,

contacts at which circuits have to be broken may have been placed so that parallel arcs or an are parallel with a conductor may have been employed but 1 f .must have been with a so I believe. that it. totally different. ob?

1 ject in 'view as in the present conditionof electrical lmowledge'electrical engineers inproximity would'place them as far apart as conveniently"possib1e.f.-I however place my stead of placing arcs or conductors in close .repellent arcs or arcs and repellent conducat the present time would be'considered as bad practice. This in the ordinary construction of a switch there must be some means tors in abnormally close or arc-extinguish ing proximity and in accordance with what of supportingthe contacts and this often I [which the movable contacts 3, 4- could be separated from the fixed contacts 1, 2 where- "as in-my invention this need not be the case-- Further, it is common practicein the con-v v structien of'sw itches' to place the contacts in separate steel chambers widely spaced apartland suchsteel chambers would present I screens against the repellent action which I a repellant conductor.

desire and upon which I rely.'

I have hereinbe'fore spoken of the-repulslon between two arcs or between an arc and cent to it two arcs in which current flows inthe opposite dlrection. The result is that each arc. is repelled outwardly in the direction of'a diagonal of the square as indicated by the arrows. In this case also instead of havlng four arcs I might b ge two arcs and two repellent conductoggs as '\\'Ill be l:1(l'il V "understood from the foregoing.

' Having thus'described my invention what 1 claim as new and des re to secure by Letters Patent is H- 1: .An electric switch coin prising a pair of terminals between which an arc is struck on I. may however ifdescribed.

separation and a parallelportion of the same circuit arranged in arc-extinguishing proximity to these terminals substantially as described.

2. An electric switch comprising pairs of terminals between each of which an arc is struck on separation having their current direction opposite, the pairs 'of terminals being arranged in arc-extinguishing proximity whereby the tendency to short circuit across the terminals is overcome, substantially as i 3. An electric switch comprising pairs of terminals between each of which an arc is struck on separation, the pairs of terminals being arranged in arc-extinguishing proximity and the distance between the pairs being less than the throw. of the switch substantially as described. I

In Witness whereof I have signed my name to this specification in the presence of two subscribing witnesses.

p PHILIP VASSAR HUNTER. Witnesses:

H. NIXON,-

A. MITCHINSON.

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