US1900647A - Electric switch - Google Patents

Description

March 7, 1933. HQQPES 1,900,647

I ELECTRIC SWITCH Filed Aug. 17, 1931 f/zomzar. 2772665 A. W66

Patented Mar. .1. 1933 umran STA TES PATENT OFFICE ERNEST A. 'HOOPES, OF DES IOIFES, IOWA ELECTRIC SWITCH Application filed August 17, 1981. Serial K015515557.

' an electric switch without friction joints, in I which there are no bearings or other surfaces subjected to friction during the operation of the switch, to" thereby provide a switch which at all times is moved to its open or closed position by the same amount of applied pressure and not ependent upon the condition of various bearmgs and friction surfaces.

A further object is to provide a switch in which the switch is especially designed for Figure shows an end elevation of same. Figures 6, 7 and 8 show respectively sectional views on the lines 66, 7-7 and 8-8 of Figure 3; and

Figure 9 shows an isometric View of the 55 supplemental spring.

Referring to the accompanying drawing, I have used the reference numeral 10 to'indicate generally the base or frame-of the switch. At one end there is a support 11 having a curved upper face and above it is a use as an automatic switch and in which a minimum degree of change in pressure will operate the switch in both directions.

A further object is to provide a switch" in which the element .provided for applying pressure to. the switch to open or close it may be given a relatively short length of 'movement.

A further object is to provide a switch in which, when the contact points arefirmly and forcibly held in actual contact during the initial states of the movement of the pressure applying element to the switch,-a relatively rapid opening movement of the switch is attained when the desired pressure has been applied. Y

My invention consists in the construction, arrangement and combinatlon of the various parts of the device, whereby the objects contemplated are attained, as hereinafter more fully set forth, pointed out in my claims, and illustrated in the accompanying drawing, in which:

Figure 1 shows a side. elevation of my improved switch with the contacts closed and the pressure applying element in its normal position. t

Figure 2 shows a similar view with the pressure applying element moved to position just prior to the opening movement of the switch.

Figure 3 shows a similar view with the switch in open position, portions being shown in section. 1

0 Figure 4 shows a top or plan view of my improved switch.

plate 12 having a curved lower face.

The main spring 13 is formed of a single pieceof relatively thin spring metal, normally concavo-convex in cross section. One end of the spring is inserted between the support 11 and the plate 12, and firmly forced into position by the screw 14.

On the under side of the free end of the spring there is mounted a contact carrier 15, preferably a straight piece of insulating material flat on its surface adjacent to the spring. The spring and contact carrier are connected by. a metal band 16 passed around them and held together by a rivet l7, and by this means the outer or free end of the main spring 13 will be flattened, as shown in Figure 6.

At the outer end of the contact carrier 15 is a contact point 18, and mounted on. the 0 base 10 is a coacting contact point 19. On the under side of the contact carrier 15 is a lever 20 fixed in position by the rivet 17 and standing spaced apart from the main spring 13 and projecting in a direction toward the support 11 for the main spring. Fixed to the free end of the lever 20 is a socket 21 having a tapered opening at its under side and a round projection 22 at its upper side projected above the lever. Interposed between the lever 20 and the spring 13 is a supplemental, substantially U- shaped spring 23 formed with a notch 24. This notch receives the projection 22 and holds the supplemental spring 23 in position.

' The means for applying pressure to the switch for moving it to open position comprises a rod 25 inserted in the socket 21,\and having its lower end inserted in a socket 26 in a plate 27. Plates of this kind are now no for lubrication and the rapid commonly em loyed in connection with that class of switc es 0 rated by fluid ressure diaphragms, and t is late 27 may used in connection with suc diaphragms or any other means .for applying pressure to the In practical operation, and assu that the switch is in the position shown in igure 1, with no pressure applied, then the main spring 13 on account of its concavo-convex shape will retain its straight line position durm the time that a considerable pressure is ap fiied to its outer end from the concave Assuming that pressure has been applied to the free end of the lever in an amount suficient to bring the parts to the position shown in Figure 2, the spring 13 has been moved upwardl a slight amount by this pressure applied through the supplemental spr' 23, which, it will be noted from an examination of Figure 2, has been considerabl compressed.

rin this movement, however, the pressure 'ap 'ed to the free end of the lever 20 causes e free end thereof to move upwardly and cause the main spring 13 at the point shown b the dotted lines 8-8 to flatten. It can easi y be bent at that point, and hence that point of the spring 13 has been bent slightly downwardly, as clearly shown in Fi re 2, and the contact carrier has been he (1 firmly in closed position during this part .of the movement.

When the pressure applied to the free end of the lever 20 is increased to a very slight amount over that required for bringing the parts to the 'tion shown in Figure 2, then some art 0 the main spring 13 assumes a stra'ig t line osition, as shown at 66 in Figure 3, an when this position has been reached, the main sp As soon as the main spring 13 flattens at one point as shown at 6-6 in Figure 3, then the supplemental spring 23 expands and moves the contact carrier to relatively wide position, and this wide open movement o 0% contact carrier is accom lished with a It will be noted that in my improved switch there are no pivot bearings or surfaces to which it is necessary to apply friction. All of the parts, except the springs themselves, can be made of material which will not rust or corrode, and the springs may be treated by any of the well known processes to prevent rust or corrosion.

-Henoe, with, my improved switch there s 13 moves very freely in a switch opening position.

opemng movement of the switch is never slowed u by thelack of lubrication or the accumm ation of rust or corrosion onfrictional surfaces thereof.

In practice I have found that with my improved switch, and when used in connection'with an air pressure tank, a certain predetermined degree of pFessure will move the switch to open position, and a relatively slight decrease in said move 1t to closed position. I

. I have also found in'use that the length 0 movement of the pressure a plying rod 25 required for moving theswi from the position shown in Figure 2, to that-shown in Figure 3, is relatively small, and that a relatively small diaphragm may be employed for causmg this small movement. I

I do not desire to be understood as limitm invention to its specifi' c use in coniitio with electric switches, because obviously the carrier member may be utilized for purposes other than opening and closing the contacts of an electric switch. s

I claim as my invention:

1. In an electric switch, the combination of a spring formed concavo-convex in cross section, means for supporting said sp at one end portion, a contact carrier on th d i'ee end portion of said spring, means for applying pressure to the concave side of said spring, and a supplemental spring interposed between the first mentioned spring and the said means for applying pressure.

2. An electric switch comprising a spring concavo-convex in cross section, means for supporting it at one end portion, a contact carrier having a flexible connection with the free end of said spring, a lever fixed to the contact carrier, means for applying pressure to said lever in a direction tending to move the contact carrier to open position, and a supplemental spring coacting with the contact carrier for increasing its opening move: ment.

3. An electric switch comprising a contact carrier, g. spring having a concavo-convex portion and being connected with the contact carrier for normally holding it in its elm position, means for applying pressure to said spring tending to move the contact carrier to open position, ,and a sup lemental spring placed under compression by the said pressure applying means and tending to increase the opening movement of the contact carrier.

4. An electric switch comprising a spring concavo-convex in cross section, means for supportingit atone end portion, a contact carrier having a flexible connection with the free endof said spring, alever fixed to the contact carrier at one end, means for appl ying pressure to the free end of the lever 1n the direction required for causing the lever to hold the contact carrier to closed position during the initial part of the movement of the spring toward open position.

5. An electric sw tch comprising a spring concavo-convex in cross section, means for supporting it at one end portion, a contact carrier having a flexible connection with the free end of said spring, a lever fixed to the contact carrier at one end, means for applyillig (pressure to the free end. of'the lever in t e rection required for causing the lever to hold the contact carrier to closed position during the initial part of the movement a contact carrier arm fixed to the other end of the spring, the end of the springadjacent to said arm beingxsubstantially flat in cross ed to the contact carrier section, a lever arm and extending in substantially parallel spaced relation to the concave side'of the said spring, a yielding pressure device interbetween said lever and said spring, and

means for applying pressure to the free end portion of said lever in a-direction tending to force it toward the said spring 7. In an electric switch, the combination of a contact carrier formed of spring metal substantially straight longitudinally and substantially concavo-convex transversely,

means for supporting it, and means for applying pressure to the concave side of the contact carrier in an amount sufiicient to cause a portion of the contact carrier to assume a substantially straight line osition V transversely at one portion to there y suddenly greatly rec-iuce the resistance of the contact carrier at that portion, and to cause a rapid movement of a portion of the contact carrier in the direction required for opening the switch.

8. The combination of a carrier member formed-of spring metal substantially straight longitudinally and substantially concavoconvex transversely, means for supporting it, and means for applying pressure to the concave side of the carrier member in an amount suflicient to cause a portion of the carrier i to cause a ra id movement of a portion of the carrier mem r in the direction in which said pressure is applied.

9. The combination of a spring substantially straight longitudinally and substantially concavo-convex in cross section, means for supporting it at one end portion, a carrier member having a flexible connection with the free end of said spring, a leverfixed to the carrier member, means for applying pressure to the lever in the direction required for causing the lever to hold the carrier member in its orlginalposition during the initial part of the movement of the spring in the direction in which the pressure is applied to the lever.

10. The combination of a spring substantially straight longitudinally and substantially concavo-convex transversely, means for supporting it at one end, a carrier member fixed on the free end of the spring, said carriers member being normally in closed position when the spring is substantially straight and in open osition when the spring has been moved cm a substantially straight line position, and means for applying pressure to the concave side of the spring to move the carried member to open posltion.

' ERNEST A. HOOPES.

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