US888760A - Circuit-breaker. - Google Patents

Description

PATENTBD MAY 26, 1908. LH. SMYTHB.

GIRGUIT` BREAKER'. PrLwATIoN FILED AUG. 17. 190s.

Y s smswnmz'r 1.

PATBNTED MAY'ze, 190s.

yf@ f EDWIN SMYTHE, OF CHICAGO, ILLINOIS, ASSIGNOR TO WESTERN OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

CIRCUIT-annalisa.

specification of Letten; Patent.

Patented May 26, 1908.

Application filed August 17, 1905. Serial No. 274,617.

To all whom it may concern:

Be it known that I, EDWIN H. SMYTHE,

citizen of the United States, residing at Ohicago, in thel county of Cook and State of Illinois, have invented a certain new and useful Improvement -in Circuit-Breakers, of which.

. the following is a full, clear, concise, and exact description.

My invention relates to an electric circuit breaker, and its object is to provide an iinproved and simple switch mechanism which will be strong and effective `in its switching operation, and capable of carrying heavy currents, while being` easy to operate and causing com aratively slight thrust or strain on the switc board.

I dispense with the laminated bridging member which is commonly used in circuit breakers, and substitute therefor a solid bridging member, or members, adapted to close the circuit between laminze constituting the Contact terminals of the electric circuit. More especially, my invention comprises circuit terminals each of which is preferably composed of a pair of laminated contacts, anda bridging member in two parts, linked together by Ia toggle arrangement, so that when they switch is being closed the parts of the bridging member are first brought freely between the 'opposing lamina1A and then spread outward with great pressure to make t eir contacts.

One of the advantages resulting from my invention is that a very close contact is made between the bridging member 'and the circuit terminals. Furthermore, when the switch is being closed, the usual carbon shunt terminals make good contact with each other before the bridging member approaches suf.- ficiently near the circuit terminals to produce an are, and likewise said carbon blocks remain in close contact While thc switch is being opened until after the circuit is broken through the bridging member; said carbon blocksl thus effectively takingthearc both when the'switch is being opened and closed.

A further advantage arising from my invention is that, owing to the peculiar construction thereof, there is very little thrust tending to o en the breaker when it is closed,

land hence t e releasing mechanism may be made lighter than that in common use, and

l can be more delicately adjusted.

`partly in section, and with parts ELECTRIC COMPANY,

I will describe my invention more -parf ticularly by reference to the accompanying drawings, in which Figures 1 and 2 are side elevations showing the switch in its closed and in its o en position, respectively; Fig. 3 is a front e evation, broken away; Fig. 4 is a sectional elevation on the line 4.-4 of Fig. 3; Fig.l 5 is a sectional plan view on the line 5 5 of Fig. 1, with parts omitted in order `to more clearly illustrate certain parts.

The same letters of reference are used to, vdesignate the same parts wherever they are shown.

vIn general Athe switch ofthe circuit breaker comprises a pivoted switch arm a carrying a brid ing member composed of a solid blade or b ades A adapted to engage and electrically unite the main contact'terininals OC",

formed of laminas mounted upon blocks ofcopper c c which are secured to the base b.V

The upper end of the switch arm ma also carry a carbon block c2, and a carbon b ook c. 'may be affixed to the block c, the carbon blocks taking the are when the switch opens, in a manner well understood.

The sprin0r ated by the handle e. The latch i holds the toggle closed, and said latch is adapted tobe released by the armature lc of the electromagnet 7c. lhe operation of these parts may d tends. to -open the switch which is readily closed by the tog rle Z, operfV be readily understood from the drawing, and

is moreover fully described in my application" Serial No. 229,476, filed Oct. 21,1904, other suitable means foro erating the switc arm may be substituted t iereforl` Y Y Upon the copper blocks c c', which in the.

devices in common use constitute' the terinnals of the electric circuit, are mounted main'.

contact terminals C C, respectively. Each of terminals CC comprises a pair of contacts, composed .of laminas, the 'o posin faces of. each air bein preferably evele outwardly as s iown at Theterminals C C are preferably bridged by two solid blades A A held in' the desired relation to each other by togglesj' The blades are here shown as having their corres l)ending'longitudinal edges parallel and the planes of their faces inclined toward each other, forming'substantially a Wedge-shaped 2 Y r .Y scares ,bridging member. I."l`he toggles ff whenexi tended thrust the blades A A in close contact with the beveled edges- CZ of the terminals C C. -Said toggles are pivotally mounted upon a'block g, Iwhich is pivotally secured by .l the pin' h to the arm a, and held in proper relation thereto by the spring m, as best shown in Fig. `ll.

The blades A A are so positioned that they readily pass between the opposing pairs of contacts C C when the circuit is being closed.

' The spreading of the blades to contact with the terminals C (1 is automatically determined by their reaching a limiting stop n at the final stage of their forwardl movement,

whereupon any further forward movement of the arm t carrles the toggles f f to spread the blades apart 'and force them into intimate 'is pivoted tothe block g. The s ring p tends to press the arm o lnwardly, and ence causes .'the'carbon shunt terminals C2 C3 to make contact' earlier and break contact later than the main switch members, as the switch is respectivelyclosed or opened. Said bloelrs y c are thus in close contact with each other before the circuit is closed through the brid ing members A A, and remain in contact wit f each other when the arm c is moved outward untilafter the circuit through said members A A is broken. 4 It is apparent therefore that the carbon blocks eflectively take the arc when the switchopens or closes.

To close the circuit by means of the bridgving member the switch arm a is movedforA ward by the manipulation of' the lever` c. The blades A A, together forming a wedgeshaped bridging member, readily enter the space between the opposing beveled' faces ofv t e main contact terminals C C. Prior to the e nals, t e carbon block c engages closely with the carbon block c. Theforward movement of the blades A A is limited 'b the stops n,

whereupon any further forwar movement ofthe arm c will'oerate the toggles j' f and spread apart the lades A A,l forcing them in ,strong contact with theV beveled faces C2 of the terminals C C. y t

If, while the s 'tch is closed, ya short circuit shouldconie upon the hue', the armature 7c' of the electromagnct lr will be drawn up andwill trip the tr'igger 7L, thus releasin the mechanism by whic 1 the 'switch is he d in .closedfposition The switch is fthen 'imme- `diately;'opened bywthel springd. When ythe switch is lin its closed positiorlimthleL membelrs vo'lesfare very near inastraig 'it liiieiga's tdibwn in Fi 5, and lience there is very littlc thrust tenl ing to open the breaker.

lll

agement of the blades with. said termi- 'are beveled outward Owing to this fact the releasing. mechanism may be made lighterrthan that in common use, and may be adjustedmore delicately.

What l claim is:

' l. ln a circuit breaker, the combination 7() with circuit terminals each`of-which has a pair of'contacts, `the opposing faces of 'which are beveled outwardly, of a wedge-shaped bridging' member composed of two parts adapted to be brought forward in between 7'5 each pair of rontacts and then laterally in opposite directions to engage the beveled faces thereof, and means for operating the bridging member to open and close `the circuit.

2. In a circuit breaker, the combination with circuit terminals having fixed contacts. of a bridging member comprising two l ades connected together bv toggles and mounted to move forward freely inbctween said con tants, and means for operating the toggles'at g5 the limit of the forward movement of the blades to spread the blades outwardly against the contacts to close 'the circuit 3. In a circuit breaker, `the combination with circuit terminals each of which has a 9o pair of laminated contacts, of a bridging member comprising two bladesconnected together bytoggles and mounted to move forward. freely in between each pair of contacts, and means for operating the toggles at the limit of the'forward movement of the blades 2A' to spread the blades outwardly against said contacts to close thecircuit. f

4. ln a circuit breaker, the combination with circuit terminals having fixed contacts, '100 the opposing faces of which are beveled, of a wedge-shaped bridging member comprising two blades connected together by toggles and mounted toniove forward freely inbe,y tween said contacts, and means for operating` the toggles at the limit of the forward movey ment ofthe blades to spread the blades outwardly agail'ist the beveled faces of said corail-"jV tants. i

5. ln a circuit breaker, the combina-tien iil@ withrircuit terminals each having;` a pair ,of ,f fixed contacts, the op osing faces of whih are bcvelerhof a wet ge shaped bridglh member comprising two blades connectedtoI f gather-by toga-lcs and mounted to movejfolfi Ward freely in between each pair of contacts, and nrieans for operating the toggles at {tgie limit of the forward movement of the lila; esJ to spread the blades outwardly against the beveled faces o f saidr contacts. i 12D 6. In a circuit breaker, the combination with circuit terminals each having ajpair of fixed contacts, the o posing faces of, wlviich gf, of a wedge `-y`shaped bridging; member comprising` two blades bonnected together by tog-glee and adapted to be freely brought in between said pairs of com i'ta'cts, means for operating the bridging member, and a stop for limiting the forward movement of the blades, whcrebyany further closing movement of the bridging mem-v `eled faces of the fixed contacts, as described.

e bevsubstantially bers is in a lateral direction against t 7. In a circuit breaker, the combination with circuit terminals, voi a airoffixed contacts secured to each of sai terminals, the opposing faces ofsaid contacts being beveled outwardly, a switch arn and means for'operating the same, a block pivoted to said switch arm, a carbon Contact pivoted to said block and electricallyn connected to one circuit terminal and adapted to e age a corresponding carbon contact'seeure t o the other clrcuit terminal, a pair of blades carried b :said block in Wedge-shaped relation' to eac tially as described.

' In Witness whereof, I-hereunto subscribe my namethis 22nd day of July A. D., 1905.A

A EDWIN H. SMYTHE. Witnesses:

DE WITT C. F.Ainxma,V JOHN G. ROBERTS.

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