US958788A - Magnetic switch. - Google Patents

Description

Patented May 24, 1910.

2 SHEETS-BEBE! 1- J. J. WOOD.

MAGNETIC SWITCH.

. APPLIOATION TILED SEPT. 29, 1905.

FIG.

. INVE NTORZ I A K \y M h l b 2 r J v @w. 0

WITNESSES: 7%;

J. J. WOOD.

MAGNETIC SWITCH.

APPLICATION FILED SEPT. 29, 1905.

Patented May 24, 1910.

2 SHEETS-SHEET 2.

INVE NTOR:

By Aim/ways,

l. to open it.

' front plate or cover UNITED STATES PATENT OFFICE.

JAMES WOOD, OF FOR 'I WAYNE, INDIANA.

MAGNETIC SWITCH.

To all whom it may concern: Be it known that I, JAMES J. Woon, a citizen of the United States residing at Fort Wayne, in the county of Allen and State of Indiana, have invented certain new and useful Improvements in Magnetic Switches, of which the following is a specification.

This invention provides a magnetically operated switch adapted to be controlled froma remote circuit.

The invention aims to provide a remote control switch which will operate with certainty, require the minimum expenditure of electric energy for its operation, and be capable of controlling a circuit of considerable capacity.

' The accompanying drawings illustrate the preferred embodiment of my invention. Figure 1 is a front elevation showing the front plate or cover of the inclosi'ng casing removed and the switch closed; Fig. 2 is a vertical mid-section showing the cover ap plied; Fig. 3 is a horizontal section through the casing showing the switch in plan; Fig. 4is an elevation of the magnet core and armature; Fig. 5 is a vertical mid-section showing the switch open; Fig. 6 is a side elevation of one pair of circuit terminals and binding posts with their insulating plate; Fig. 7 is an elevation of one of the switch levers; Fig. 8 is a plan of a fragment of the switch showing the open position thereof.

Referring to the drawings, let A designate any suitable inclosin case or box having a K. These should beof fireproof material, as cast iron, and in order to inclose the working parts 'andprotect them against'tampering, the cover is fastened on by screws 6 b engaging lugs a a. The screw heads are embedded in a'boss 0, through which is drilled transversely a hole d. By turning the screwdriver nick in the screw so as to coincide with this hole, a seal joined by a seal f, as shown in Fig. 3, whereby the casin is sealed against any attempt Dr any other means for locking of sealing the casing may be substituted.

The ends of the circuit wires are intro- .duced through holes 9 g, preferably in the sides of the casing, and are fastened in binding posts BB, as best shown in Figs. 5.-and 6. These posts are formed as tubular sockets with set-screws in the usual manner, and are preferably made integral with conpoint through an electric bridge or brush F, which Specification of Letters Patent. Patented May 24, 1910, Application filed September 29, 1905. Serial No. 280,591:

nection plates C C (Fig. 6) which are also formed integrally with the terminal contact plates D D of the switch. The connection plates C C and their appurtenances are fas-.

- passing through holes 2' (Fig. 6). Any other known and suitable means for mounting the terminal contacts D D andmaking electric connection between them and the circuit wires, may be adopted. For a double pole switch these contacts and binding posts, one

cated on opposite sides of the casing, as,

shown.

For closing the circuit, the contacts D D are bridged or connected by a conducting lever G pivoted at y to lugs in the easing. The lever .G is duplicated for a double-pole switch, and the two levers G G are operated simultaneously and oppositely by means of a suitable electro-magnet H through any suitable mechanical connection. If it is desired that the excitation of the magnet shall close the switch, the parts are best arranged as shown.

' set of which is shown in Fig. 6, are dupliis carried by a The magnet H is designed to afford a short magnetic circuit with the minimum separation at'the gap, so as to afford a powerful pull with the minimum expenditure of current in the exciting coil." The magnet core comprises a fixed part I and a movable part or armature J. These project partly within the exciting coil K, preferably so far that when the magnet is excited they form a practically continuous inner core, as shown in Fig. 2. The fixed part I has legs which extend down outside of the coil and terminate in polar ends, partly inturned, and with angular faces, as clearly shown in Figs. 4 and 5. The movable part or armature J has its external portion expandedlaterally so as to .early meet the polar ends of the fixed core, as best shown in Fig. 4. Both. the fixed and movable cores are preferably laminated as shown. The

magnet is arranged to draw the movable cessity of using a retracting spring, which would be requlred if the magnet were arranged in any other position.

The movable core or armature ofthe magnet is connected to the levers G G so as to move the latter simultaneously toward or from the'respective airs of fixed contacts D D. This connection is made in a simple manner by toggle links L L, which are referably duplicated at the front and ack sides of the armature, as shown, being pivoted loosely thereto on a pin is. The

' bushings g.

of liLIIllHtB united byscrews or rivets'to rear plates I, whlch are fastened at top angular position shown in thickness of the armature necessitates se a-} rating these links somewhat widely,'an to provide for this the levers G G are formed with prolonged bosses Z Z.

The arrangement of the toggle links L L is such that the upward attraction of the armature J draws these links from their Fig. 5, to a position nearly in alinement as shown'in' Fig. 1, thereby forcing the levers G G apart, and consequently forcing the conducting bridges F F against the fixed contacts with a considerable degree of force, wherebya electric contact is assured. The links The exciting coil K is fixed in place in any fixed coreI, the ends ofthe coil being carried to binding osts p p, to which are fastened the ends 0? the wires 9 which is to control the swltch, these wires passing into the casing[through insulatin The core is shown as forme to posts 1 r w1th1n the casing, and, at their bottom ends are bent back and fastened by screws 1" to the back plate of the casing.

The conducting bridges F F are of peculiar construction.

' leaves or brushes 8 s of resilient sheet metal,

preferably copper, fastened at their middles to a yoke, t, which latter has ears embracing. and pivoted to the upper end of the lever G. The laminae s are bent or bowed and graduated in length so that their ends turn toward the fixed contact plates D D, so

that when the switch is closed they make good.

however, are not so nearly alined that they.

clearly suitable manner wlth reference to the q of the circuit They are made up. of

in Fig. 3. In the closing movement the laminae first touch lightly against the contact plates, and then by the straightening out of the toggle links are forced more firmly against them, the bowed laminae beleaf is pressed individually against the contact plates, and its. ends make individual edgecontact thereagainst, and during the flattening. of thebowed laminae their: ends rub against the surfaces of the contact plates, whereby the respective contact surfaces are kept clean and bright. The laminae are thin enough to give'the requisite flexibility, and yet thick and stiff enough to firmly transmit the pressure to the contact faces, and they are sufiiciently numerous to afford the requisite conductivity for carrying any required current. Thus the capacity of the switch may be'varied of the laminm constituting the conducting bridges FF. For the'protection of these laminae and of the fixed contacts from injury by arcing du'ring the opening movement of the switch, they are backed by the leaf or lamina 10, preferably of thicker and stiffer" sheet metal, and which is given a greatercurve, so that in the open position its ends extend beyond the ends of the laminae s s, as shown in Fig. 8. movement of the switch the ends of this spring or leaf a touch the fixed contacts first, and as the conducting bridge is flattened by the circuit-breaking movement the laminae tened to the greatest extent so that its endsare thrust apart as shown in Fig. 3. In the circuit-breaking movement the laminae s first part contact with the fixed contact plates, so that in the receding movement of main in contact, and continue to remain in contact until the movin arts have acfalling of the armature, so that when they finally separate from the fixed contacts, a quicker; break is made. Whatever sparking or arcin accompanies the break in the circuit, fol ows the ends of the leaf u, so that the corrosion is' confined to these. ends, and the laminae s are protected from corrosion and left clean and bright. The corrosion due to arcing is also limited to the extreme outer edges of thefixed contact plates, so that the remainder of their surface which coacts with the laminae 8, remains clean and bri ht. The leaf a being of heavier metal, is etter adapted to carry the momentar arcs than the thinner laminae 8, and to st-il better. adapt it for this urpose, its ends are thickened or increased in mass by the provision of enlargements u. To carry this corrosion away from the normal contactirg end or edge contact therewith, as shown surfaces,'the enlargements u are rolong upwardly as shown, and the fixe contacts n'ilg thereby partly flattened, so that each.

In the closing quired a considerable ve ocity due to the between wide limits by varying the number the bridge the ends of the leaf u alone reprojections v o. .Thus the arcs formed durmg the opening movement instantly travel to the upward projections u v, and the subsequent corrosion occasioned b the arcs is wholly limited to these upwar projections. The switch casing may be provi ed with the usual lugs w for attaching 1t to a support, orit may in any other known way be fastened in place. 7

-My invention is susceptible of considerable modification in structural details, and is not to be understood as limited to the precise features of construction set forth. Those features of my improved switch which are believed to'be novel, are set forth in the claims. It is to be understood that certain features of my invention may be availed of without necessarily using the remaining features thereof.

' As far as concerns the laminated bridge F, my invention is not limited to this part levers comprising a coil, a

constituting strictly a bridge, since if one side alone be used making contact with onlyit one of the plates D D, my invention will be to that extent utilized.

What I claim -is: 1. An electric switch comprising opposite fixed contacts, levers pivoted at their lower ends and carry- I in at their upper ends the respective movab e contacts, an electroma netbetween said fixed core exterior thereto servmg as a stop to limit the movement of the levers, and a movable member, and toggle linksconnecting at their outer ends to said levers and atxtheir intermediate joint to said movable member, and adapted upon the excitation of the magnet to apoppositely movable contacts,-

apart to force the movable contacts a ainst the respective fixed contacts, and on t e demagnetization of the magnet and the retraction of said movabl member to draw gamst the intervening said levers together magnet.

2. An electric switch fixed contacts,

movable contacts mating therewith,

one of each pair of contacts being laminated, an electro-magnet comprising a coil, :1 fixed core exterior thereto and a movable member entering partly within said coil and extended partly exterior thereto as 'proach alinement, and by forcing said levers 40 comprising opposite an armature, and subject to a constant re- .tracting force, and toggle links connecting at their outer ends to said movable contacts and at their middle joint to said movable member, and arranged with said middle joint below the ends in the retracted position of said movable member and in the open position of the switch, and adapted as the movable member is attracted to approach alinement, whereby during the free closing movement of the switch the through the toggle with increasing mechanical advantage and during the final portion of the movement when the resistance is increased by the flexure of the laminae both the mechanical advantage of the toggle and the magnetic attraction of the armature are at their'maximum.

, In witness whereof,I have hereunto si ned my name in the presenceof two subscri ing witnesses. 5

JAMES J. WOOD. Witnesses:

EDWARD A. BAXUES, A. A. SERVA.

Images