US2472333A

US2472333A - Snap acting electric switch

Info

Publication number: US2472333A
Application number: US597555A
Authority: US
Inventors: Everard F Kohl
Original assignee: Individual
Current assignee: Individual
Priority date: 1945-06-04
Filing date: 1945-06-04
Publication date: 1949-06-07
Anticipated expiration: 1966-06-07

Description

June 7, 1949;

3 Sheets-Sheet 1 Filed June 4. 1945 IN VEN TOR. Everard F. Kohl ATTORNE Filed June 4, 1945 June 7, 1949. E. F. KOHL. 2,472,333

SNAP-ACTING ELECTRIC SWITCH 3 Sheets-Sheet 3 IN V EN TOR. Everard F. Kohl ATTORNEY Patented June 7, 1949 UNITED STATES PATENT OFFICE i 2,412,333 SNAP ACTING ELECTRIC swrron Everard F. Kohl, Lakewood, Ohio Application June 4, 1945, Serial No. 591,555

' (c1. zoo-7o)- 20 Claims. 1

My invention relates to electrical switches and znore particularly to switches of the snap acting In electrical switches oi. the snap acting type, it has heretofore been the practice to utilize a portion of the blade of the switch or a comparetively thin spring arm as the current-carrying member and consequently the current-carrying capacity of such switches is limited unless a comparatively large switch is employed. Considerable difflculty has also been experienced in modifying switches of the ordinary snap acting type to provide a small, compact switch of the multipole type.

It is the purpose of the present invention to provide an improved switch of the snap acting type having a comparatively high current-carrying capacity that is small in size and in which the parts are easy to fabricate and assemble. My improved switch may be utilized to interrupt and establish a single circuit, or to interrupt one circuit and establish another circuit, or may be of the double pole, double throw type in which a plurality of circuits are interrupted and a plurality oi. circuits are established during each throw of the switch and the parts are arranged so that when the switch is in either of its two alternative positions, the contacts are held in place by the tension of a pair of balanced springs which are disposed in overlapping relation to occupy a comparatively small space. Compact spring means are also provided in my improved switch for returning the parts to their original position when the force upon the actuating means is released which spring means also serve to permit overtravel of the actuating means without injury to the switch parts.

It is therefore an object of my invention to provide an improved switch of the snap acting type that is small in size and which has a comparatively high current-carrying capacity.

Another object of my invention is to provide an improved switch in which a pair of contacts are movable into engagement with a pair of stationary contacts with a snap motion and are maintained in seating engagement therewith by resilient means which exert a balanced pressure upon the movable contacts and are arranged in overlapping relation to occupy a comparatively small space.

A further object of my invention is to provide an improved switch of the multipole, double throw type. in which during each throw of the switch at least four movable contacts engage four stationary contacts and are maintained in seating engagement therewith by resilient means which exert the same or substantially the same pressure upon each of the movable contacts.

A still further object of my invention is to provide an improved switch in which compact spring means are provided to return the parts to their original position when pressure upon an actuating plunger is released and which spring means also function to permit overtravel of the actuating means without injury to the switch parts.

Other objects and advantages of my invention will be apparent as the specification proceeds.

My invention will be better understood by reference to the accompanying drawings in which:

Fig. 1 is a. plan view of my improved switch with parts broken away to show underlying structure;

Fig. 2 is a cross sectional view on the line 22 of Fig. 1 with parts shown in elevation;

Fig. 3 is a central cross sectional view of the switch with the movable parts in a position different from that shown in Fig. 2;

Fig. 4 is a cross sectional view on the line 44 of Fig. 2;

Fig. 5 is a cross sectional view on the line 5-5 of Fig. 2;

Fig. 6 is a detail plan view of the spring actuat ing means carried by the shaft;

Fig. 7 is a detail plan view 01 one of the actuating springs; and

Fig. 8 is a cross sectional view on the line 8-8 of Fig. 1.

As illustrated in the drawings, the movable parts of the switch,are enclosed in a housing,

the walls oi. which are formed of a suitable electrically insulating material, such as a molded phenolic condensation product, and while the housing may be of any desired shape and formed of any suitable numberv of parts, as illustrated in the drawings, it comprises an upper section I, a central section 2, and a lower section 3 which sections are provided at opposite ends with aligned apertures through which sleeves 4 and 5, respectively, extend to hold the parts together and provide openings to receive suitable mounting bolts, not shown.

The central section extends outwardly beyond the upper and lower sections at each corner to form posts '8, I, 8 and '9, each of which provides a seat for upper and lower terminal bars 10 and II, respectively, and each post is provided with upper and lower apertures to receive screws I2 and I 3, respectively, each of which extends through a threaded aperture in one of the terminal bars and is adapted to maintain a suitable conductor in place.

provided on its inner face with a stationary contact. As illustrated, bars l and II of post 6 are provided with stationary contacts l and I6, respectively, bars I and II of post I are provided with stationary contacts I! and I8, respectively, bars l0 and H of corner post 8 are provided with stationary contacts l9 and 20, respectively, and bars l0 and II of corner post 9 are provided with stationary contacts 2| and 22, respectively, and while the contacts maybe composed of any suitable conductive material and be afilxed to the terminal bars in any desirable manner, as illustrated, each contact is composed of a comparatively strong member, such as steel, which is welded or otherwise aflixed to the face adjacent the inner margin of its terminal bar and to which is brazed another member having a comparatively high conductivity, such as silver.

Arranged within the chamber M are the movable parts of the switch which are actuated by movement of a suitable plunger 23 slidably extending through an aperture in the raised central portion 2% of upper section I. V

The movable parts of the switch include a floating shaft or carrier 25 formed of a suitable electrical insulating material, such as a molded phenolic condensation product, a pair of actuatingsprings 26 and 2'6, a support 28 for one end of each spring, a resilient spring 29 which may be welded or otherwise amxed, such as by a rivet 25m, to support 2t for returning the parts to their original position when the force upon the plunger is released, and a block 36 formed of an insulating material, such as a phenolic condensation product, which is adapted to be engaged by the base 35 of the plunger 23.

Shaft or contact carrier 25 extends across the chamber id and its opposite ends terminate in

flanges

32 and 33. Shaft 25 is also provided with collars 3d and 35 formed integral with the shaft and spaced equal distances from the opposite ends and carries between flange 332 and collar a pair or movable contacts, each of which has oppositely disposed portions 36 and 37 and 3d and Sid, respectively, and while these contacts may he carried by the shaft in any suitable manner, as illustrated in the drawings, two mating bars 4 6| to provide an aperture to receive shaft and upper plate 48 is provided with centrally disposed notches' in its side margins to receive

tongues

52 and 53 on the lower plate which extend through the notches and are bent over plate to maintain the plates in position on the shaft.

Plates

48 and 49 are also provided with central openings and extending inwardly from the plates are oppositely disposed

tongues

54 and 55 and the ends of support 28 are bent inwardly to form abutments which are provided with oppositely extending tongues 56 and 51. Springs 26 and 21 are similar in construction and each is provided with apertures adjacent the opposite ends and as shown tongue 54 extends through an aperture adjacent one end of spring. 26 and tongue 55 extends through an aperture adjacent one end of spring 21. The opposite end of spring 26 is arranged adjacent one of the inwardly extending abutments on support 28 and tongue 51 extends through the aperture adjacent that end and dd and M, see Figs. 4 and 5, are provided having oppositely disposed central grooves which provide an aperture to receive the shaft and the opposite ends of the mating bars are provided with apertures and are connected together by a pin or rivet joining

portions

36 and 3? of the movable contact at one end and

portions

38 and 39 of the movable contact at the opposite end. In a like manner, two

mating bars

22 and 63 arranged between collar 35 and flange 33 are provided with oppositely disposed central grooves at their central portion to form an aperture to receive shaft 25 and with aligned apertures at their opposite ends, one of which receives a pin or rivet connecting two oppositely disposed portions 84 and of a movable contact and the opposite end re ceiving a pin or rivet connecting two oppositely disposed portions :36 and tl of another movable contact.

Means carried centrally by shaft 25 is provided to support one end of each of the springs 26 and 2'? so that upon movement of plunger 23 to a predetermined extent the movable contacts carried by the shaft may be forced into engagement with the stationary contacts carried by terminal bars it with a snap motion. For this purpose, a pair of

plates

38 and 49 are provided, the ends of each of which have oppositely disposed grooves and in alike manner the opposite end of spring 21 is arranged adjacent the other inwardly extending abutment on support 28 and tongue 56 extends through the aperture adjacent that end, and while the opposite ends of each

spring

26 and 21 may be connected to the tongues in any desirable manner, as illustrated, the apertures in the opposite ends of each of the springs are of suflicient size to permit one end of spring 26 to engage and rock upon the abutments of the support opposite tongue 51 and its opposite end to engage and rock upon abutments on plates 58 and d9 opposite tongues as during actuation of the switch and in a like manner, th apertures in spring 2? are of sumcient size to permit spring 2? to engage and rock upon abutments on support 28 opposite tongue 56 and to engage and rock upon abutments on plates 88 and d9 opposite tongues during actuation of. the switch.

The manner in which springs 26 and 27 rock upon their supports during actuation of the switch is now well known in the art and is described more particularly in Patent No. 2,237,!05 granted to me on April 8, 1941.

Springs

26 and 27 are preferably formed of thin fiat strips of resilient metal of spring temper, such as steel, brass, bronze, a beryllium-copper alloy, or the like, as illustrated in Fig. 7 of the drawings, and consequently they may be readily formed of identical lengths and with apertures of the same size in the margins adjacent each end. Pressure may 'then be applied to the opposite ends of each of the springs so that one aperture in each spring receives one of the tongues on the support and the other aperture in each spring receives tongues extending inwardly from one side of plates 18 and t9 and since

springs

26 and 21 are arranged in similar relation with respect to support 28 and to. shaft 25, it will be apparent that a balanced relation exists by means of which the

upper portions

36, 38, M and d6 of the movable contacts may be forced into engagement with stationary contacts 115, ll, 99 and 2| and will be held in such position by the force of springs 26 and 2'! while plunger 23 is held in the position shown in Fig. 3. It will also oe noted that

springs

26 and 21 are arranged in overlapping relation with their arcuate-shaped portions opposed to each other so that a compact arrangement may be provided even when comparatively large springs are utilized and that during actuation of the switch they rock upon their supports in opposite directions to maintain this compact arrangement irrespective of the position of the contacts.

To actuate the switch, pressure is applied to plunger 23 which places tension on spring 29 and

rocks springs

28 and 21 on their supports, thus changing'their direction of force until they reach a critical position at which tim the

upper portions

38, 38, 44 and 46 of the movable contacts are forced into engagement with stationary contacts [5, I1, l9 and 2! with a snap motion, thus providing a circuit between terminal bars III on posts 1 and 8 and terminal bars l8 on

posts

6 and 9 as shown in Fig. 3 of the drawing.

when the switch is in its actuated position, it will be noted that the current flows through

bars

48 and 4| in its passage from terminal bar secured to post 8 to terminal bar I8 secured to post 1 and in a like manner it flows through

terminal bars

42 and 43 in its passage from terminal bar In on post 9 to terminal bar 18 on post 5. These bars while short are comparatively thick and consequently my im roved switch is adapted to interrupt circuits transversed by comparatively high currents.

its upward movement carries support 28 with it, thus rocking

springs

28 and 21 upon the abutmentson support 28 and

plates

48 and 49 adjacent the tongues, changing the direction of the force of

springs

26 and 21 until they reach a critical position at which time the springs cooperate to force

portions

31, 39, 45 and 41 of the movable contacts into engagement with station- Spring 29 is so constructed and arranged that when pressure is applied to plunger 23, tension -is placed upon the spring and consequently when the pressure upon plunger 23 is released, spring 29 functions to return the movable parts of the switch to their original position. For this purpose, spring 29 is provided with

legs

58 and 59 which engage and slide upon the wall forming the bottom of chamber l4 during actuation of the switch and to facilitate this sliding action, the legs are provided with arcuate-

shaped portions

60 and 6| which engage the bottom wall of the housing as illustrated in Figs. 2 and 3.

To increase the resilience of spring 29 and to provide a compact structure,

legs

58 and 59 are of less width than the

strips

62 and 63 which constitute the side walls of the spring and leg 58 is oifset from one edge of strip 62 and leg 59 is offset from the opposite edge of strip 53 so that the

legs

58 and 59 will lie in overlapping relation to each other and the combined width of the two legs, including the space between them, is of the same width as

side walls

62 and 63.

In view of the structure of spring 29 when pressure is first applied to plunger 23, the arcuate-shaped portions 68 and 6| of

legs

58 and 59 slide upon the bottom of the housing. During this pretravel, spring 29 and support 28 are moved inwardly rocking

springs

26 and 21 on their abutments until they reach a critical position at which time springs 26 and 21 cooperate to force shaft 25 and the movable contacts carried by the shaft upwardly with a snap motion, thus

forcin portions

36, 38, 44 and 46 of the movable contacts into engagement with stationary contacts l1, l9, l5 and 2! respectively, and when the springs are in this position, they cooperate with each other to exert a balanced force to maintain the upper portions of the movable contacts in en-" gagement with the upper stationary contacts.

During this movement, it will be noted that additional tension is placed upon spring 29 and that the termini of legs 68 and 6| slide over the bottom wall on the housing to the position shown in Fig. 3. When the spring is in this position, however, thetermini of the legs still do not engage the side walls of the housing so that after the switch is actuated, plunger 23 may be compressed still further to provide a limited amount of overtravel without injury to the switch parts.

When the force upon plunger 23 is released, the tension upon spring 29 is also released and plunger 23 is forced outwardly and spring 29 in ary contacts I8, 28, I6 and 22, respectively thereby establishing an electrica1 circuit between terminals H on posts 1 and 8 and terminals II on

post

8 and 9. When the switch is. in this position as illustrated in Figs. 2 and 8, it will be noted that springs 26 and 21 cooperate to maintain the movable contacts in firm seating engagement with the stationary contacts and that stationary contacts l8 and 20 are bridged by

terminal bars

40 and 4| and

stationary contacts

16 and 22 are in a like manner bridged by

terminal bars

42 and 43. The terminal bars 48, 4|, 42 and 43 while short are comparatively thick and consequently my improved switch although small will have a comparatively high current-carrying capacity.

What I claim is:

1. Apparatus of the class described comprising a housing having a bottom wall, a pair of stationary contacts and a pair of movable contacts arranged in said housing, an actuator slidably mounted in said housing, means for throwing the movable contacts into engagement with the stationary contacts upon movement of said actuator, and resilient meanscompressible upon movement of said actuator for returning the parts to their original position, said resilient means including side strips and a pair of legs, each of which legs is offset from a different edge of said side strips and said legs being arranged in overlapping relation to occupy a comparatively small space, and said legs being slidable upon said bottom wall during movement of said actuator.

2. Apparatus of the class described comprising a housing having a bottom wall, a pair of stationary contacts and a pair of movable contacts arranged in said housing, an actuator slidably mounted in said housing, spring means for throwing the movable contacts into engagement with the stationary contacts upon movement of said actuator and resilient means compressible upon movement of said actuator for returning the parts to their original position, said resilient means including side strips and a pair of legs, each of which legs is ofiset from a different edge of said side strips and said legs being arranged in overlapping relation to occupy a comparatively small space and being engageable with and slidable upon said bottom wall during movement of said actuator and said resilient means being movable after the movable contacts have been thrown into engagement with the stationary contacts to permit overtravel of the actuator.

3. An electrical switch comprising a housing having a central chamber bounded by oppositely disposed end walls, an actuator slidable through one of said end walls, a pair of spaced stationary contacts arranged in said chamber, a pair of movable contacts arranged in said chamber which are electrically connected together, a pair of arcuate-shaped springs arranged in overlappin relation associated with said actuator and the movable contacts and being movable in response to the inward movement of said actuator for throwing the movable contacts into engagement with the stationary contacts, and resilient means associated with said actuator and arranged at an angle thereto which are of sufficient length to air/aces engage andslide along the wall opposite to that through which the actuator extends to store energy during the inward movement of the actuator to return the actuator to its original position when the force upon the actuator is released.

4. An electrical switch comprising a housing having a central chamber bounded by side and end walls and one of said end walls being provided with an aperture, a pair of stationary contacts arranged in said chamber, a movable shaft, a pair of movable contacts mounted on said shaft which are in electrical connection with each other, a plate mounted on said shaft having oppositely disposed tongues, an actuator slidable in said aperture and having oppositely extending abutments provided with tongues, a pair of arcuate-shaped springs, each having apertures arranged adjacent its opposite ends and said springs being arranged in overlapping relation with one of the apertures in each spring loosely receiving a tongue on said abutment and the other aperture receiving a tongue on said plate, a pair of arms associated with said actuator and arranged along said walls, each of which terminates in a resilient prong which prongs are inclined relative to said arms and which slide on the end wall of said chamber opposite to that through which the actuator extends, and said actuator being effective in rocking said springs on the abutments adjacent said tongues to force the movable contacts into engagement with the stationary contacts with a snap motion and to slide said prongs upon the end wall of the housing which they engage to store energy to return the parts to their original position. 7

5. An electrical switch comprising a housing having a central chamber bounded by side and end walls-and one of said end walls being provided with an aperture, a pair of stationary contacts arranged in said chamber, a movable shaft, a pair of movable contacts mounted on said shaft which are in electrical connection with each other,

a plate mounted on said shaft having oppositely.

disposed tongues, an actuator slidable in said aperture and having oppositely extending abutments provided with tongues, a pair of arcuateshaped springs, each having apertures arranged adjacent its opposite ends and said springs being arranged in overlapping relation with one of the apertures in each spring loosely receiving a tongue on one of said abutments and the other aperture receiving a tongue on said plate, a pair of arms associated with said actuator which terminate in resilient prongs that slide on the end wall of said chamber opposite to that through which the actuator extends, said actuator being effective in rocking said springs on the abutments adjacent said tongues to force the movable contacts into en gagement with the stationary contacts with a snap motion and to slide said prongs upon the ends of the housing to store energy to return the parts to their original position, and said prongs being spaced from the side walls when the movable contacts enga e the stationary contacts to permit overtravel of the actuator.

6. An electrical switch comprising a housing having upper, central and lower hollow sections which cooperate in their assembled form to provide a central chamber and the central section being extended outwardly beyond the upper and lower sections at portions arranged opposite to each other and the upper section being provided with an aperture, a pair of terminal bars, one of which rests on the central section at one of the outwardly disposed portions and extends into said chamber and the other of which rests on the other outwardly disposed portion and extends into said chamber and which is arranged in spaced relation to the other bar, and said bars being held in engagement with the central section by one of the other sections, a stationary contact amxed to the end of each bar which extends into said chamber, a pair of spaced movable contacts arranged in said chamber and being electrically connected to each other, a carrier for said movable contacts, an actuator, and a pair of springs arranged in said chamber which are disposed in overlapping arrangement with respect to each other, each or said springs having one end associated with said actuator and the other end associated with said carrier, the actuator being slidable through the aperture, in the upper section into said chamber and said springs being responsive to the move ment of said actuator for throwing the movable contacts into engagement with the'stationary contacts.

7. An electrical switch comprising a housing composed of upper, central and lower hollow sec tions-which cooperate in their assembled form to provide a central chamber and the centrai section having portions extending outwardly b-e-= yoncl the upper and lower sections at portions arranged oppositely to each other and the upper section being provided with an aperture, a pair of upper and a pair of lower terminal bars with each terminal bar of the upper pair resting on one of the outwardly disposed portions of the central section and extending toward each other into the central chamber and each being provided with a stationary contact arranged in the central chamber which contacts are spaced from each other to provide a pair of upper stationary c0n= tacts and each terminal bar of the lower pair being disposed against opposite outwardly disposed portions on the central section with one end of each extending into the central chamber to form end portions within the central chamber which are spaced from each other and each of the lower bars being provided with a stationary contact arranged within the chamber to provide a pair of spaced lower stationary contacts, and said terminal bars being held in place by the upper and lower sections, a pair of spaced movable contacts arranged in said chamber which are electrically connected to each other, a floating carrier for said movable contacts, an actuator, and a pair of springs arranged in said chamber which are disposed in overlapping arrangement with respect to each other and which normally maintain the-movable contacts in engagement with the lower stationary contacts, each of said springs having one end associated with said actuator and the other end associated with said carrier, said actuator being slidable through the aperture in the upper section into said chamber and said springs being responsive to the movement of said actuator for throwing the movable contacts into engagement with the upper stationary contacts.

8. An electrical switch comprising a pair of spaced stationary contacts, a centrally disposed floating shaft, 2. second pair of spaced contacts which are movable into and from engagement with the stationary contacts and the contacts of the second pair being arranged on opposite sides of said shaft and being electrically connected together and supported by said shaft, an actuator, means movable with said actuator having an abutment. arranged on each side of said shaft, means secured to said shaft and providing supports on opposite sides thereof, first and second similar arcuate-shaped springs, the first arcuateshaped spring having one of its ends loosely secured to the support at one side of said shaft and being rockably mounted thereon and its other end being loosely secured to the abutment arranged on the opposite side of said shaft and being rockably mounted thereon and the second arcuate-shaped spring being loosely secured to the support extending from the opposite side of said shaft and being rockably mounted thereon and having its opposite end loosely secured to the other abutment and being rockably mounted thereon and the movement of said actuator being effective in rocking said springs upon said supports and said abutments to change the direction of the force of said springs a sufficient extent when said actuator has been moved a predetermined distance to cause a snap motion of said shaft to force the movable contacts into en agement with the stationary contacts and to maintain a substantially balanced resilient force upon the movable contacts to maintain them in engagement with the stationary contacts when the actuator is held in one position.

9. An electrical switch comprising a pair of spaced stationary contacts, a centrally disposed floating shaft, a second pair of spaced contacts which are movable into and from engagement with the stationary contacts and the contacts of the second pair being arranged on opposite sides of said shaft and being electrically connected together and supported by said shaft, an actuator, means movable with said actuator having an arm arranged on each side of said shaft, each of which arms has a tongue extending therefrom, means secured to said shaft having a support arranged on opposite sides of the shaft, each of which has a tongue extending therefrom, first and second similar arcuate-shaped springs, each having openings at opposite ends thereof, the first arcuate-shaped spring being secured at one of its ends to the support at one side of said shaft with the tongue of the support extending loosely through one of its openings and its other end bein securedto the arm arranged on the opposite side of said shaft with the tongue of the arm extending loosely through its other opening and the second arcuate-shaped spring being secured to the support extending from the opposite side of said shaft with the tongue of the support extending loosely through one opening and the opposite end of the second spring being secured to the other arm with the tongue on said arm extending loosely through its other opening, and

said arcuate-shaped springs having their bows extending in reverse directions and being disposed in overlapping relation to conserve space and the movement of said actuator being effective in moving said arms to rock said springs on the supports adjacent said tongues to change the direction of the force of said springs and to cause a snap motion of said shaft when said actuator is moved a predetermined distance to force the movable contacts into engagement with the stationary contacts with a snap motion and to maintain a substantially balanced resilient force upon the movable contacts to maintain them in engagement with the stationary contacts when the actuator is held in one position.

10. Apparatus of the class described comprising a housing having a bottom wall, a pair of stationary contacts arranged in said housing, a centrally disposed floating shaft, and asecond pair of spaced contacts arranged in said housing, said second pair of spaced contacts being movable into and from engagement with the stationary contacts and being, arranged on opposite sides of said shaft and being electrically connected together and supported by said shaft, an actuator slidably mounted in said housing, means movable with said actuator having arms arranged on opposite sides of said shaft, means secured to said shaft and providing supports arranged on opposite sides of the shaft, first and second similar resilient members, one of said resilient members being secured to the support arranged on one side of said shaft and to the arm arranged on the opposite side of said shaft and the other resilient member being secured to the support arranged on the opposite side of said shaft and to the other arm to thereby maintain said shalt in a balanced relation, the movement of said actuator being effective in moving said arms to change the direction of the force of said resilient members and to cause a snap motion of said shaft when the actuator is moved a predetermined distance to force the'movable contacts into engagement with the stationary contacts with a snap motion and to maintain them in engagement with the stationary contacts when the actuator is held in one position, and resilient means associated with said actuator having portions disposed in overlapping relation and engaging the bottom of said housing which are flexed during the movement of said actuator to store energy therein which is efiective in returning the parts to their original position when the force upon the actuator is released.

11. An electrical switch comprising a pair of spaced upper stationary contacts, a pair of spaced lower stationary contacts, a centrally disposed fioating shaft, a third pair of spaced contacts which are movable from engagement with the lower spaced contacts into engagement with the upper spaced contacts and from engagement with the upper spaced contacts into engagement with the lower spaced contacts, the third pair of spaced contacts being arranged on opposite sides of said shaft and being electrically connected together and supported by said shaft, an actuator, means movable with said actuator and having an abutment arranged on each side of said shaft, means secured to said shaft and providing supports on the opposite sides thereof, first and second similar arcuate-shaped springs, the first arcuate-shaped spring having one of its ends loosely secured to the support at one side of said shaft and being rockably mounted thereon and its other end being loosely secured to the abutment arranged on the opposite side of said shaft and being rockably mounted thereon and the second arcuate-shaped spring being rockably secured to the support extending from the opposite side of said shaft and beingrockably mounted thereon and having its opposite end loosely secured to the other abutment and being rockably mounted thereon, said springs being normally effective in maintaining the movable contacts in engagement with the lower pair of spaced contacts and the movement of said actuator being effective in rocking said springs upon said supports and said arms to change the direction of the force of said springs a sufficient extent when said actuator has been moved a predetermined distance to cause snap motion of said shaft to force the movable contacts into engagement with the upper pair of stationary contacts and to maintain a substantially balanced resilient force upon the movable contacts ill, to maintain them in engagement with the upper stationary contacts when the actuator is held in its lower position,

12. An electrical switch comprising two pairs of upper spaced contacts in which the contacts of each pair are spaced from each other, two pairs of lower spaced contacts in which the cnntacts of each pair are spaced from each other, a floating carrier provided with o first oil electrically connected spaced contacts adjacent one end and a second of elcctriy connected spaced contacts adjacent the other end which are electrically pair, an actuator, a pair of new springs, one end of each of which isconnected to said carrier and the other end of each oi wch is movable with said actuator, said sprs om normally effective in said carrier in position to maintain one pair oi" the contacts carried thereby in engagement with one of. the lower pairs oi contacts and the other pair oi con tacts carried thereby in easement with the other pair of lower contacts, said springs being responsive to the moveent oi said actuator for moving said carrier with a snap motion to force one pair of the contacts carried thereby into engagement with one pair of the upper contacts to establish an electrical circuit therebetween and to force the other pair oi contacts carried thereby into engagement with the other pair of spaced upper contacts to establish an electrical circuit therebetween.

13. An electrical switch f. *r a p of spaced stationary contacts, a pair of spaced movable contacts electrically connected together, a centrally disposed movable carrier on ch said movable contacts are mounted, a plate mounted on said carrier having oppositely ex tending tongues arranged on opposite sides of said carrier with abutments ged on the opposite sides of each of said tongues, an actuator,

u irem the the oneness a support movable in response to the movement of said actuator, said support having a tongue arranged on one side of said carrier with abutments adjacent the opposite sides of said tongue and a. tongue arranged on the opposite side of said carrier with abutments sides thereof, first and second or arcuateshaped springs veach having apertures at its end margins, said springs being arranged in overlapping relation with their bows win opposite directions, the first arcuatesped spring having one end rocka'blymounted on one of the abutments on on the plate extending loosely through the aperture in the opening at one 0! its end margins and the other end 01 said spring being rockably mounted on the support arranged on the opposite side of the carrier with the tongue on the support extending loosely through the other opening in the spring, and the second spring having one end rockably mounted on the other abut: ment on said plate with one oi the marginal openings in the spring receiving the other tongue on said plate and its opposite end being rockably mounted on the other support with the tongue of that support extending loosely through its other marginal opening, and said springs being rockable on said abutments in response tothe movement of said actuator and support to change the direction of the force of said springs to a sufllcient extent to move said carrier with a snap motion to force the movable contacts into engagement with. the stationary contacts.

14. An electrical switch comprising a housing said plate with the tongue arranged on opposite in overlapping having a central chamber bounded by oppositely disposed top and bottom walls and oppositely disposed side walls, a pair of spaced stationary contacts arranged in said chamber adjacent the top wall, a pair of movable contacts arranged in said chamber below the stationary contacts and being electrically connected together, a carrier for said movable contacts. an actuator slidable through the top wall and having oppositely disposed supports elated therewith, a pair of spring means ed in overlapping relation with one end of each spring means connected to said carrier and its opposite end connected to one of said supports, and second spring means associated tvith said actuator having oppositely disposed. a n used along am ite side walls of the er chamber which terminate in free ends inclined with respect to the side arms with the free ends or the arms being arranged in overlapping relation; said being of sumcient length to engage the bottom wall and said actuator being ective during inward movement to move said carrier with a snap motion to force the movable contacts into engagement with the stationary contacts and to slide the free ends of said arms along the bot wall to store energy therein to return the parts to their original position when the force upon the actuator is released.

15. Anelectrical switch comprising a housing having a central chamber bounded by oppositely disposed top and bottom walls and oppositely disposed side walls, a pair of spaced stationary contacts arranged in said chamber adjacent the top ll, a pair of movable contacts arranged in said to: ber below the stationary contacts and being electrically connected together, a carrier for said movable contacts, an actuator slidable h the top wall having oppositely disposed supports associated therewith, a pair of spring means arranged in overlapping relation with one end of each spring means connected to said carrier and its opposite end connected to one of said supports, and second spring means associated with said actuator having oppositely disposed arms arranged along opposite side walls and each of said arms terminating in a prong of less width than the arm to which it is connected, and said prongs being inclined at an angle to the arm to which it is connected and being of sufllcient length to engage said bottom wall, said actuator being efiective during inward movement to move said carrier with a. snap motion to force the movable contacts into engagement with the stationary contacts and to slide said prongs along the bottom wall to store energy therein during the inward movement of said actuator to return the parts to their original position, and said prongs being spaced from the side walls when the movable contacts engage the stationary contacts to permit overtravel of said actuator.

16. Apparatus of the class described comprising a housing having a bottom wall, a stationary contact and'a. movable contact arranged in said housing, an actuator slidably mounted in said housing, resilient means associated with said actuator and the movable contact for causing engagement of the movable contact with the stationary contact upon movement of said actuator, and second resilient means compressible upon movement of said actuator for returning the parts to their original position, said second resilient means including side strips and a pair'of legs, each of which legs is offset from a difierent edge of said side strip and said legs being arranged relation to occupy a comparatively 7 carrier which is opposite to the small space, and said legs being slidable upon said bottom wall during movement of said actuator.

17. An electrical switch comprising a. pair of spaced stationary contacts, a floating carrier having first and second supports arranged on opposite sides thereof, a second pair of spaced contacts movable into and from engagement with the sta-' tionary contacts and the contacts of the second pair being arranged on opposite sides of said carrier and being electrically connected together and supported by said carrier, an actuator, means movable with said actuator having a first abutment spaced from said carrier and arranged on that side of said carrier which is opposite to the first support and a second abutment spaced from said carrier and arranged on that side of said second support, first and second resilient members arranged in overlapping relation, thev first resilient member being connected to the first support on said carrier and to the first abutment and the second resilient member being secured to the second support on said carrier and the second abutment to thereby maintain said carrier in a balanced state, and the movement of said actuator being eflective in changing the direction of the force of said resilient members to cause a snap motion of said carrier when said actuator is moved a predetermined distance to force the movable contacts into engagement with the stationary contacts with a snap motion.

18. An electrical switch com-prising a, pair of spaced stationary contacts, a fioatin-g carrier having first and second supports arranged on opposite sides thereof, a second pair of spaced contacts movable into and from engagement with the stationary contacts and the contacts of the second pair being arranged on opposite sides of said carrier and being electrically connected together and supported by said carrier, an actuator, means movable with said actuator having a first abutment spaced from said carrier and arranged on that side of the carrier which is opposite to the first support and a second abutment spaced from said carrier and arranged on the side of the carrier which is opposite to the second support, first and second arcuate-shaped springs arranged in overlapping relation, the first spring having one end connected to the first support on said carrier and its other end to the first abutment and the second spring having one end connected to the second support on said carrier and its other end connected to the second abutment to thereby maintain said carrier in a balanced state, and the movement of said actuator being effective in changing the direction of-the force of said resilient members to cause a snap motion of said carrier when said actuator is moved a, predetermined distance to force the movable contacts into engagement with the stationary contacts with a snap motion.

19. An electrical switch comprising a pair of spaced stationary contacts, a floating carrier having first and second supports arranged on opposite sides thereof, a second pair of spaced contacts movable into and from engagement with the stationary contacts, and the contacts of the second pair being arranged on opposite sides of said carrier and being electrically connected together and s pported by said carrier, an actuator, means movable with said actuator having a first abutment spaced from said carrier and arranged on that side of the carrier which is opposite to the first support and a second abutment spaced from said carrier and arranged on that side of the carrier which is opposite to the second support, first and second arcuate-shaped springs arranged in overlapping relation with the bow of the first spring extending in a reverse direction to the box of the second spring to conserve space, the first spring having one end connected to the first support on said carrier and its other end to the first abutment and the second spring having one end connected to the second support on said carrier and its other end connected to the second abutment to thereby maintain said carrier in a balanced state, and the movement of said actuator being effective in changing the direction of the force of said resilient members to cause a snap motion of said carrier when said actuator is moved a predetermined distance to force the movable contacts into engagement with the stationary contacts.

20. An electrical switch comprising a pair of spaced stationary contacts, a floating carrier, a conductor supported by said shaft and having arms extending in opposite directions therefrom, a movable contact connected to each arm of said conductor, said carrier having a first support on one side thereof and a second support on the opposite side thereof, an actuator, means movable with said actuator having a first abutment spaced from said carrier and arranged on that side of said carrier which is opposite to said first support and a second abutment arranged on that side of said carrier which is opposite to said second support, first and second arcuate-shaped springs arranged in overlapping relation with the bow of the first spring extending in a direction reverse to the bow of the second spring to conserve space, and the first spring having one end connected to said first support and its other end connected to said first abutment and the second spring having one .end connected to said second support and its other end connected to said second abutment to thereby maintain said carrier in a balanced state, and the movement of said actuator being effective in changing the direction of the force of said springs to cause a snap motion of said carrier when said actuator is moved a predetermined distance to force the movable contacts into engagement with the stationary contacts.

EVERARD F. KOHL.

REFERENCES CITED The. following references are of record in the file of this patent:

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