US477409A - Edwin t - Google Patents

Description

(No Model.)

E. T. GREENFIELD. ELECTRIC vSWITGH.

No. 477,409. Patented June 21, 1892.

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EDXVIN T. GREENFIELD, OF NEWT-YORK, N. Y., ASSIGNOR TO THE IN'TRIOR CONDUIT'AND INSULATION COMPANY, OF SAME PLACE.

ELECTRIC SWITCH.

SPECIFICATION forming part of Letters Patent No. 477,409, dated June 21, 1892. Appiicafionfiiednecemha16,1891. `seria No. 415,253. Numan To a/ZZ whom t may concern.-

Be it known that I, EDWIN T, GEEENEIELD,

a citizen ofthe United States, residing at New York, in the county of -New York and State of New York, have made a new and useful Invention in Electrical Switches or Circuit Making and Breaking Devices, of which the following is a specification.

My invention is directed particularly to a lo novel device for preventing what is known as arcing7 between the electrodes of a switch designed to carry large-quantity or high-tension currents-such, for example, as is used in electric lighting and analogous electrical I5 systems.

For a full, clear, and exact understanding of theinvention here claimed reference is had tothe following specification, taken in connection with the accompanying drawings, in all of which like letters of reference indicate like or analogous parts wherever used.

Figure l of the drawings is a transverse sectional view of a well-known form of two-pole snap-acting switch having my improvement attached, the circuit being shown as closed, while Fig. 2 is a similar view showing the circuit open. Fig. 3 is a side or elevational view of the same switch with the cover partly broken away to better illustrate the interior construction thereof and to show, also, my improvement in connection therewith. Fig. 4 is a side elevational view of a well-known forni of jackknife-switchwith my improvement attached; and Fig. 5 is a transverse sectional view of the same, taken through the operative parts thereof.

It is a well-known fact that where a circuit carrying a large-quantity current or a current of high potential is ruptured there appears at the point of rupture an arc, which in course of time as the circuit is many times broken will seriously impair the electrodes. Numerous devices have been utilized for overcoming or preventing this are. To illustrate, currents or puits of air have been forced upon the electrodes, thereby blowing out the are. Magnets, both permanent and electro, have been utilized for drawing it aside and rupturing it. The electrodes have been immersed in oil, water, or alcohol with a view of extinguishing the arc. These and other methods,

all more or less successful, have been utilized; but no one, so far as I ain aware, has ever resorted to a positive means of disrupting the are by injecting a spring-actuated are intereepter or snui'fer between snap or spring acting electrodes which suddenly rupture a circuit, and my improvement is of this general nature.

I will now describe my improvementin de- 6o tail. B represents the base of a snap-switch, made, preferably, of porcelain, and O the cover thereof. h I) and b o are binding posts or screws secured to the base, adapted one pair to receive the wires w w on one side and the other pair to receive the corresponding wires on the other side. S S and S S' are the snap-acting contact-springs,secured one pair to the posts h l) and the other pair to the posts b h', said springs being double-leafed at their 7o free ends, the inner leat` of each pair being turned outward, as shown. E is the switchshaft, pivotally secured to the base B and provided with an operating-handle H. D is a revolving ratchet-block secured to the shaft E and held in place by a transverse pin j). All of the parts so far described are well known in the art and constitute, when assembled, what is known as a hand-switch, in which the circuit is open between the springs S S 8o on one side and S S on the other when their free ends lie in the notches of the ratchetblock D in the position shown in Fig. 2 and is closed when the ends of said springs are in contact, as shown in Fig. l.

My improvement consists in providing a pair of are interiupters or snuffers A A of insulating material-such as vegetable fiber, glass, or the like-and preferably wedgeshaped and of a width greater than the width 9o ofthe springs, said parts being attached to the free ends of springs t t, secured in turn to the binding-posts l) and h or to any part of the switch box or base. The springs t t are preferably in the nature of corrugated strips, as shown, and their normal tendency is to force the interrupters or snuters inward toward the free ends of the inner springs S and S, thereby intercepting the arc. rllie mode of operation is obvious, it being linden loo stood that at the instant the free ends of the inner springs S S drop oil the ledges or ratchets of the insulating ratchet-block D the interrupters or snuiers will be forcibly thrust forward, thereby snufling out or intercepting the are. I find that with such an arrangement the arc is effectually disrupted.

Fig. 4 illustrates the application of my improvement to j ackknife-switches, K bein g the jackknife, pivoted at P in the usual manner and adapted to contact at its free end between the electrode-plates P P2. In this instance the interrupters or snuiTers A A are attached to the free ends of the springs t t, which in turn are secured to the electrodeplates P P2. Vhen the blade K is drawn upward, the interrupters or snuffel-s A A are forced together into the path of the arc and it is snuled out. If preferred, the snuiers A A may be carried by the blade K.

I do not limit myself to the specific apparatus herein shown and described for effectually snuiing or wiping out an arc between positive or snap-acting electrodes, as I believe I am entitled to claim, broadly, the combination of one or more pairs of spring-actuated or other positive snap-acting` electrodes with instantaneous or positive spring actuated snufiing devices adapted to be inserted between the electrodes at the instant that they are separated by such positive snap action.

Having thus described my invention, what I claim, and desire to secure by Letters Patent of the United States, is-

l. A pair of snap-acting` electrodes, in combination with a springactuated arc-interrupter of insulatingmaterial for interccptinfl,r an arc established between said electrodes, substantially as described.

2. A switch provided with one or more pairs of snap-acting electrodes, in combination with a spring-actuated arc-interrupter of insulating material for each pair of electrodes.

3. A switch, a pair of spring-actuated electrodes, with their free ends resting normally on a ratchet-block made of insulating` matcrial, in combination with a spring-actuated arc-interrupter of insulating material, substantially as described.

et. A switch provided with two pairs of spring` actuated electrodes and a ratchetblock secured to an operating-handle, in co|nbination with spring-actuated arc-interrupters of insulating material adapted to pass between the ends of the electrodes and disrupt the are7 substantially as described.

EDWIN T. GREENFIEL'D. lVitncsses:

EDWARD F. SEIXAs, CHAS. J. KINTNER.

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