US1700268A - Electric switch - Google Patents

Description

Jan. 29, 1929. 1,700,268

G. N. LEMMON ELECTRIC SWITCH Filed June 27, 1925 Fig. 1 7

7 a? N LEMMO/V.

Paamea Jan. 29, 1929.

GEORGE N. LEMMON, or BIRMINGHAM, ALABAMA.

ELECTRIC swrrcn.

Application filed June 27, 1925. Serial No. 40,065.

My invention relates to electric switches, and more particularly to air break switches for use upon high potential circuits.

The object of my invention is to provide an air. break switch having ample clearance for proper operation at high voltage and which afibrds suflicient pressure between jaws and switch blade to give ample current carrying capacity while at the same time being operable to open and close it without imposing objectionable strains upon the porcelain in-' sulators, one of which is movable to actuatethe switch. a

My invention contemplates operating the switch by means'which will impart a double motion to the blade, on motion being arcual to provide the wide clearance between con tact parts when the switch is swung to opened or closed position and the other being a short motion longitudinal of the switch blade which is effective during a part of the blade stroke and which is powerfully executed by reason of the available high leverage, to force the blade into or to withdraw it from the switch jaws.

My invention further contemplates the modification of the operating mechanism to swing the blade arcually either horizontally or vertically as may be desired.

vMy invention further comprises'the novel details of'construction and arrangements of parts, which in their preferred embodiment only are illustrated in the accompanying drawings which form a part of this specification, and in which Fig. 1 is a side view of a horizontal throw switch with the blade shown aboutto enter the jaws with a longitudinal movement. Fig. 2 is a plan view showing the position of the blade relative to its actuating means during its arcuate motion. 7

Fig. 3 is a plan view showing the blade at the com letion of the arcual motion and just before t e commencement of the powerful drive which imparts to the blade its short longitudinal motion which forces it into the 1 switch jaws.

Fig. 4 is a plan view showing the switch blade thrust into closed position between the aws.

Similar reference numerals refer to similar parts throughout the drawings.

Referring to the embodiment of my invention shown in Figs. 1 to 4, I show the mechanism mounted upon a suitable base 1 carrying standard high tension current insulators 2 and 3, the insulator 3 being arranged for rotation about the pivotal bearing 4. The crank arm 5 ofl'ers a means for rotating the insulator 3 and for operating the switch either singly or in combination with a group of similar units. proper comprises a longrigid blade 6 which co-acts with the switch jaws 7 mounted upon an insulator 2, the switch blade itself being pivotally mounted on a pin 8 disposed at the top of the insulator 3,near its center. -The blade is disposed between'two fixed stops 9 and 10 on the insulator 3 and is free to have a limited swinging movement between these stops. A spring 11, attached directly to the switch blade on the side adjacent to the stop 10, normally engages said stop and provides a means for keeping the switch blade, when free of contact with the jaws, in position against the stop 9. The jaws 7 have the usual flaring edges to receive and guide the switch blade into position between them and in ad dition thereto one of the jaws is provided with a stop 13 against which the blade will strike so that it cannot swing through'the outer or. free ends of the jaws. The jaws of the switch, as viewed in plan, are cut away diagonally and the enlarged end 12 of the Switchblade also has-its edge corresponding- 1y bevelled so that when the switch blade completes its free arcual swing its end will lie between and parallel with the diagonal edges of the jaws. as is seen more clearly in Fig. 3. l

In operation, when the switch is. open the switch blade assumes the position shown in :Fig. 2 and is held against the stop 9. As the crank 5 is swung around, it rotates the insulator 3 and imparts an arcuate stroke to the blade, causing the latter to swing freely towards and to engage between the ends of the jaws 7, as shown in Fig. .3. Thereupon' the arcuate stroke of the switch blade is completed and the further rotation of the insulator will act to compress the spring. 11

and permit the blade to swing over against the stop 10. In thus swinging the pivot point moves through an are which will act to impart a short powerful longitudinal motion to the switch blade that results in thrusting- -its end 12 deeply and firmly between the jaws 7; i. e., from the position shown in Fig. 3 to that shown in Fig. 4, and this completes the closing of the switch. In reversing the movement of parts to open the switch, the initial movement imparted'by the crank to The' switch mechanism position.

Though I have described with great particularity the details of the embodiment of .the invention herein shown, it is not to be construed that I am limited thereto, as changes in arrangement and substitution of e ui'valents may be made by those skilled in t e art without departing from the invention as defined in the appended claims.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is

1. In an electric switch, a stationary assembled insulator carrying a stationary contact member, a bodily movable assembled insulator, a loosely pivoted switch arm carried by the movable insulator, means to limit the swing of the pivoted arm on the movable )insulator, and means to swing said movable insulator thereby to make or break the switch contact with successive lineal and angular motions of the switch arm.

2. In. an electric switch, a stationary insulator carrying a stationary contactmember, a bodily movable insulator having pivotally mounted thereon a movable contact member,

means carried by the movable insulator to limit its swing, and crank means to swing said movable insulator about an axis parallel with the axis of the pivot connection of the contact member to operate the switch.

3. An electric switch according to claim 2,

in which a spring means is provided to urge the pivoted switch element towards the stationary contact'member.

4. An electric switch according to claim 2, in which the movable contact member is pivoted on the movable insulator substantially nearer to the latters axis than is the point of power application to the crank means.

5. In an electric switch, a stationary insulator carrying a stationary contact member, a bodily movable insulator having a rigid contact arm pivotally mounted on the top thereof to swing in a plane at right angles to the axis of the insulator, stop means to limit the swingof saidarm relative to the movable insulator, spring means adapted to urge the arm towards said contact member, and a crank having the movable insulator mounted thereon with its axis eccentric toand parallel with the axis of the crank, whereby the movable insulator is swung bodily to cause the switch arm thereon to have a component motion in making and breaking contact with the stationary contact.

In testimony whereof I aflix my signature.

GEORGE N. LEMMON.

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