US1289996A - Electric switch. - Google Patents

Description

6. WRIGHT.

ELECTRIC SWITCH. APPLICATION FILED MY 5.1915.

Patentefl Dec. 31, 1918..

\nventor:

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Hi5 'Attorn eg UNITED STATES PATENT @FFTQE.

GILBERT WRIGHT, OF SOHENECTADY, NEW YORK, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

ELECTRIC SWITCH.

T 0 (1 whom it may concern:

Be it known that I, GILBERT VVRIGHT, a citizen of the United States, residing at Schenectady, county of Schenectady, State of New York, have invented certain new and useful Improvements in Electric Switches, of which the following is a specification.

My invention relates to electric switches and the like, and more particularly to the construction and inclosure of electric switches in such a way as to minimize the danger of operating and working with them and with the apparatus that they control. My invention comprises various features and details of operation and construction and various combinations and arrangements of parts that can best be disclosed by the description of a particular apparatus embodying them, -its scope being indicated in my claims.

In the accompanying drawings, Figure 1 is a side elevation of the apparatus with the switch closed, the side of the inclosing casing being cut away.

Fig. 2 is a view from beneath, various parts being in section at a surface corresponding to the broken line 2-2 in Fig. 1.

Fig. 3 is a view similar to Fig. 1 with the switch open.

Fig. 4 is a side view of a locking device.

Referring first to Figs. 1 and 2, it Will be seen that the amiaratus shown comprises a switch proper 10 of ordinary three blade construction mounted on a base 11 of slate or other insulating material. Also mounted on the base 11 and appropriately connected with the switch 10 are fuse holding means 1: shown as in the form of receptacles oi the Edison screw type adapted to receive or dinary plug fuses. secured to the bottom of nursing 13 which incloscs the switch 10 and the receptacles i2 and other accessory parts. This casing 13 is shown as a substantial sheet-iron box with its upper and lower ends rounded in front; preferably its joints or seams are electrically welded. The box proper has upper and lower openings where thus rounded, and rounded covers it and 15 are provided to close these openings. The cover l-l (for as the covers 14 and 15 are exactly alike onlyone of them need be described) has a twocared bracket 16 ot' channel-like form welded to its lower edge, and this bracket 16 (its between brackets or cars 17, l? fastened to Specification of Letters Patent.

The switch base 11 is Patented Dec. 31, 1918.

Serial No. 25,909.

the front portion 18 of the box proper between the aforesaid openings and is pivoted to said brackets 17 by a pin or bolt 19. Through switch actuating means presently to be described the covers 14: and 15 are so interlocked with the switch 10 that the latter must be actuated to open the circuit before either cover can be opened. The covers 1% and 15 always tend to close under the action of tension springs 20, 20. The upper cove! 1% gives access to the switch 10; the lowe1 cover 15 to the fuse plug receptacles 12.

The switch apparatus shown being intended for push and pull operation and also to give a quick make and break, its actuating means includes a reciprocating operating member 21 that extends through the casin front 18 and a spring mechanism interposed between said member and the switch proper It). The member 21 comprises two parallel strips 23, of sheet metal secured together and spaced apart in any suitable way, and is provided with a convenient handle. The member 21 slides between the brackets 17, 1'5 and between the cars of the brackets 16, 16 and in ways in a channel-like girder 524 that extends across the casing 13 behind the front portion 18, These ways, itwill be seen, are formed by the sides of the channel 2% and by depending extension pieces 25 attached to brackets or cars 26 secured to the lower side of the front portion 18 by screws 27 that extend down through the brackets 17, 11?. Coming, now, to the spring mechanism through which the switch 10 isordinarily actuated, it will be seen that on the inner side of each of the bracket extensions 25 a. rocker member 2a is pivoted at 29. and to the ends of the rockers 28, 25% (on their outer sides) the forward ends of links 50, 30 are pivoted by means of a pin 31. The rear cuds of th links 3!), 2-30 are pivoted at 32, 32 to logs or ears attached to the inner side of the insulating bar 3-1 that unites the free ends of the switch blades. 0n the pin 31 (but between the ends of the rockers 28, 28) is pivoted a block 36 in which is secured one end of a rod 37 which slides freely through a block 38 pivtnied at 33) between the lower ends of the strips 523, of which.

spring, 41 that serves mainly to cushion the movements of the parts and to take up backlash,

From the foregoing description it will be evident that when the parts are in the positions shown in Fig. 1 and pressure is applied to the member 21 to push it inward the pivot 89 will move downward and toward the pivots 21), 29, and that the spring will be compressed and will exert on the block 36 a pressure tending to hold the switch 10 closed. As, however, the pivot 39 passes the line of centers oi the pivots 29,29 and 3l,which is a. dead center for the parts 28, 28 and 37,-the spring 40 will be left free to expand and throw open the switch 10 as shown in Fig. 3; and at the same time it will throw the member 21 inward as also shown in that figure. This action will be very rapid and powerful, so that any arc that may be drawn will. be quickly broken. 'hen the parts are in the positions shown in Fig. 3 and a pull is exerted on the member 21 the switch 10 will be closed with a similar quick action, and member 21 pressed to its outward limit.

In the lower end of the member :21 is fixed a pin -12 whose protruding ends slide in slots in the bracket extensions 25, and thus limit the in and out. movement of. the 111811} her. It will be seen that if the spring it) should fail to throw the switch 10 in either direction,whether from sticking; ot the parts, breakage of the spring, or any other cause,the pin will come against one end of an enlarged foot portion -18 of each of the rockers 28, 28 and either positively open or close the switch or start it so as to cause the spring to throw it.

So far nothing has been said regarding the interlocking of the switch 10 with the covers 14, 15 except that it is accomplished through the switch operating means. It has, however, been pointed out that the strips 23, 23 of the operatin member :21 slide just between the edges or the ears on the brackets 16, 16. From this fact and the various figures of the drawing, it will be evident that when the member :21 is pulled out and the switch 10 closed as in Fig. 1 the edges of said strips 23, will effectually block such movement of said ears as must take place when the covers 14, 15 are swung open; whereas when the men'iber 21 is pushed in to open the switch 10 as shown in Fig. 3 the notches =14 in the strips 23, will be opposite said ears and allow the covers to swing q'iite freely. A very slight outward movement of the member 21 from the position of Fig. 3. wholly insullicient to throw the switch, will block the covers 1i, completely. Finally, it will be observed that when the parts are as shown in Fig. 3 and the cover 14 has been opened it is possible to take hold of the member 3i with the hand and move the switch 10 toward the closed position, but that before the pivot 39 has passed the dead center or the switch blades have approached their contacts suliiciently to cause any danger of arcing the lower ends of the rocker portions 43 will encounter the pins l2 and movenn-rnt will be blocked. It follows, therefore, that the switch 10 cannot be closed except by the operating member 21; neither can it. be brought to an intermediate position where it will remain if released.

It will be observed that in the member 21 there is a slot -15 and that the brackets 16,16 have extensions l6, 16 that approach one another very closely and overhang this slot, when the switch 10 is open and the covers 14, 15 are closed (see By inserting the locking element 50 in this slot l5 and snapping a padlock 51 in one of the holes 52, SStherein it will be rendered impossible to manipulate the members 2'1 to close the switch 10 or to open either at the covers 14, 15. lily inserting the element 50 in simi lar slots 17, f? in the braciret ears 1?, 1?, opening of the cover 14 will be prevented without interference with the cover 15 or with the manipulation of the switch 10. The various holes 52, 53 in the element 50 allow the switch apparatus to be controlled by several persons, as the electrician in charge of repairing the motor controlled by it and the machinist in charge of machinery driven by said motor,so that each will be protected against any other by merely using his own padlock.

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

1. The combination of a casing having an opening and swinging closure means therefor, an electric switch in said casing, op erating means for said switch includinga member which interposes directly in the path of swing of said closure means except when the switch is in open position, a yieldable connection between said operating means and said switch whereby the latter is moved with a snap action, and means for locking the switch open whilethe closure means remain open.

2. The combination of a casing having an opening and swinging closure means therefor, a switch in said casing, reciprocating actuator for said switch including a mernher which inter-poses directly in the path of swing of said closure means except when the switch is open, a rocker connected to said switch and mounted on a stationary axis, and a spring connection between said rocker and said actuator adapted to be moved from side to side of said rocker axis by said actuator.

ii. The combinat on of a casing having an opening with a door therefor, a switch in said casing, a reciprocating actuator for said switch having a member which directly intel-poses in the path of swing of said door exceptwhen tl .2 switch is in open position, a rocker connected to said switch, a spring connecting said rocker to said actuator, and interlocking means to prevent the'closure 01' said switch while said door remains in open position.

4. The combination of a casing having openings at opposite ends of one side and an intervening central portion, doors hinged to said central portion, a switch in said casing, and a reciprocating actuator for said switch having a notched member passing through said central portion adjacent said hinges and adapted to interpose directly in the path of swing of said doors except when said switch is open.

opening and movable closure means therefor; a switch in said casingand actuating means for said switch inclu inga pull and push operating member which extends out through the wall of the casing in the path of movement of said closure means in opening, said member being notched so as to permit opening of said closure means when the switch is open, a spring mechanism interposed between said operating member and the switch and adapted to give a quick make and break, and additional means associated with said member for opening and closing the switch positively if said spring mechanism fails to do so.

In Witness whereof, I have hereunto set my hand this 30th day of April, 1915.

GILBERT WRIGHT.

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