US2647179A

US2647179A - Double-pole double-throw snap switch

Info

Publication number: US2647179A
Application number: US140069A
Authority: US
Inventors: Wilbert A Martin
Original assignee: Honeywell Inc
Current assignee: Honeywell Inc
Priority date: 1950-01-23
Filing date: 1950-01-23
Publication date: 1953-07-28
Anticipated expiration: 1970-07-28
Also published as: DE917320C; GB675716A; FR1032723A

Description

July 28, 1953 w. A. MARTIN 7 DOUBLE POLE DOUBLE THROW SNAP swrrcn Filed Jan/23, 1950 2 Sheets-Sheet 1 8/ 7z ma i. a; 86 4 5a M INVENTOR. 64 I i 52 37 9 Mad QM i y Z! Z 2 '3 27 4L ATTYS July 28, 1953 w. A. MARTIN 2 647,17

DOUBLE POLE DOUBLE THROW SNAP SWITCH Filed Jan. 23, 1950 V 2 Sheets-Sheet 2 INVENTOR. 74% Q.

Patented July 28, 1953 DOUBLE-POLE DOUBLE-THROW SNAP SWITCH Wilbert A. Martin, Freeport, Ill., assignor, by mesne assignments, to Minneapolis-Honeywell Regulator Company, Minneapolis, Minn, a corporation of Delaware Application January 23, 1950, Serial No. 140,069

19 Claims. 1

This invention relates to snap acting devices and more particularly to a double pole double throw snap acting switch.

An object of this invention is to provide a double pole double throw snap acting switch that has the same overall and mountingdimensions as a standard precision snap acting switch.

Another object of the invention is the provision of a double pole double throw switch having a novel snap acting spring system that effects a positive pressure between the movable and the fixed contacts until the instant of movement of the movable contacts between the fixed contacts, and that insures a uniform pressure between the movable contacts and the fixed contacts.

Another object of the invention is the provision of a novel snap acting spring system having a novel combination of levers for obtaining successive snap movements.

Another object of the invention is the provision of a double snap acting spring system that is simple to construct, that is easy to assemble, that is positive in its action, that is rugged, that has a relatively long service life, and that is rel- I atively inexpensive to manufacture.

Other objects and advantages of the invention will become apparent from the following detailed description taken in connection with the accompanying drawings, in which Figure 1 is a perspective view of a double pole double throw snap acting switch embodying the present invention;

Fig. 2 is an enlarged side elevational view of the switch shown in Figure 1 with portions of a side wall cut away to show details of construction of the spring system;

Fig. 3 is a sectional view taken substantially along the line 3-3 of Fig. 2;

Fig. 4 is a greatly enlarged fragmentary side elevational view of the switch similar to Fig. 2 with members of the snap acting spring system in section and the driving member of the spring system in a position to urge the movable contacts into engagement with the lower contacts;

Fig. 5 is a sectional view taken substantially along the line 55 of Fig. 3;

Fig. 6 is a view similar to Fig. 4 showing the relation of the parts prior to the first snap movement;

Fig. 7 is a view similar to Fig. 4 showing the position of the parts following the first snap movement;

Fig. 8 is a view similar to Fig. 4 showing the relation of the parts after the second snap move-'- ment;

Fig. 9 is a section-a1 view taken substantially along the line 99 of Fig. 4, and

Fig. 10 is an enlarged sectional view taken substantially along the line l0l0 of Fig. 2.

The invention is shown embodied in a double pole double throw electric switch. In general the latter comprises a pair of mobile-contacts 2| movable between opposed positions, a double snap acting spring system. 22 interconnected with the mobile contacts 2! and operable to move the latter between opposed positions with a snap action and a plunger 23 for actuating the double snap acting spring system 22. The mobile contacts 2| and the spring system 22 are disposed in a chamber 24 of a housing 26. The latter may be formed from any suitable material such as insulating material and includes a base or support 21 and a removable cover 28 interfitting with the base 21 to define the chamber 24. The plunger '23 is of conventional construction and extends through the cover 28 for engagement with the spring system.

The mobile contacts 2| (see Fig. 2) are disposed centrally of the chamber 24 and are mounted on the free ends of spaced contact carriers 29, in this embodiment of the invention, elongated flexible resilient leaf springs. The opposite end of each carrier is secured, as by welding or the like, to one end of a support 3| (one only being shown) to provide a cantilever mounting for carriers 29. Each support 3| rests on a shoulder 32 formed near one end of the chamber 24. The opposite end of the support 3| is offset with respect to the end supporting the carrier 29 and is secured to the base 21 as by a screw 33 threaded into the support 3|. Each screw 33 also secures a terminal 34 to the bottom of the base 2! accessible for connection to an external circuit.

Disposed to be engaged by each of the mobile contacts 2| are spaced fixed stops or contacts 36 and 31, which may form an upper contact and a lower contact. The upper contacts 36 are formed by spaced elongated rigid metallic strips, each strip being mounted in a cantilever fashion on a shoulder 38 spaced above the shoulder 32. The free end of each strip overlies a mobile contact 2i and is engageable thereby when the movable contacts are in their upper position as shown in Fig. 8. Each strip is secured to its respective shoulder 38 by a rivet 39 extending through the strip, the base 21 and a terminal 4i, mounted on the bottom of the base 21, to be accessible for connection to an external circuit. The lower contacts 31 are formed by metallic elements each having a pad 42 and a free end 43 offset with respect to the pad and disposed directly below and in spaced relation with one of the strips forming the contacts 36. Each free end 43 is disposed to be engaged by one of the mobile contacts 2| when the latter are in their lower position as shown in Fig. 2. Each lower contact is secured to the base 27 as by a rivet 44 extending through the pad 42, the base 21 and terminal 45 mounted on the base and accessible from the exterior of the housing for connection to an external circuit. A rib 4'! formed on the bottom of the housing separates the terminals 4|, 34 and 45 adjacent one side of the housing from the terminals 4|, 34 and 46 (not shown) adjacent the opposite side of the housing. Where desired the strips, forming the contacts 36, and the elements, forming the contacts 37, may be provided with inlaid contact surfaces to insure a good electrical contact between the mobile contact 2| and the

contacts

36 and 3?. A partition 48 extending from one end of the chamber 24 to a central portion thereof separates the contacts 35, 2| and 31 adjacent one side of the chamber from the contacts 35, 2| and 31 adjacent the opposite side of the chamber 24 so as to prevent arcing r flashing therebetween.

The double snap acting spring system 22 is disposed adjacent the free ends of the leaf springs 29 and is interconnected with each leaf spring 29 to move the mobile contacts 2| between the contacts 36 and 31 with a snap action. In this en.- bodiment of the invention the spring system includes a bracket an anchor 52, an actuator 53, a coil spring 54, a toggle link 56 and a driver 51. The anchor 52 includes spaced upstanding sides 58 (see Fig. 9) and a pad 59 on the base 21. The bracket 5| includes an upstanding portion 8| and a pad 62. The pad 62 rests on the pad 59 and the upstanding portion 5| is spaced from the side portions 58. A rivet 63 extending through the pads 82 and 59 and the base 21 secures the anchor 52 and bracket 5| to a shoulder 54 formed near the end of the chamber opposite to the shoulders 38.

The actuator 53, best shown in Figs. 2, 3 and 4, is pivotally supported on the bracket 5|, the upstanding portion Bl of which has upwardly projecting ears 66 adjacent the edges for the reception of the actuator therebetween. The upper ends of the ears are provided with 1nwardly extending lugs 51 adapted to overhang the actuator and retain the same in place. One

.end of the actuator is shaped to cooperate with the ears 6B in pivotally supporting the actuator and has a portion 68 snugly but freely received between the ears 55 below the lug 5? and provided with laterally disposed tabs 69 shaped to bear against one side of the ears 65 as best shown in Figs. 2 and 3. The pivotal connection between the actuator and the bracket 5| is referred to hereinafter generally by the numeral N. This construction maintains the parts in assembled position and prevents movement of the actuator 53 transversely of the bracket 5|. The end of the actuator 53 spaced from the bracket 5| s bent back upon itself and shaped to form a pro ection 12 shaped to pivotally engage a recessed end cap 13 on one end of the coil spring 54. The p votal connection between the cap and the projection is referred to generally by the numeral 14.

The rigid toggle link 56 as best seen 1n F1g 3 is generally U-shaped and comprises a br dg ng portion 16 and spaced legs 11. The bridging of the bracket portion 15 extends through an aperture 19 in the bracket 5| and is movable between opposed positions or stops defined by the upper side wall 8| defining the aperture and the head 82 of the rivet 53 which secures the pad 52 on the base. A projection 83 is formed on the bridging portion between the legs T! to pivotally support the cap 84 on the opposite end of the coil spring 54, the pivotal connection being designated generally by the numeral 38. The legs 7'! of the toggle link are spaced to permit movement of the actuator 53 therebetween. As best seen in Fig. 4 the outer ends of the legs 11 are offset with respect to the bridging portion 3'5 to overlie the sides 58 of the anchor and the extreme outer ends of the legs have depending flanges 81. Each of the flanges 81 has a pivotal recess formed thereon facing the bridging portion (5.

The driver 57 as best seen in Figs. 3 and 4 is formed as a rigid member and includes wings 83 formed along opposite edges of the driver and an end portion 89 disposed centrally of the wings and interconnecting the latter. One end of each wing 68 is formed with a knife edge 9! shaped to be received in one of the recesses on the flanges 81 to define a ivotal connection between the parts, indicated generally by the numeral 92. Tabs or shoulders 84 on each wing, disposed outwardly from the knife edge, are disposed to engage the sides of the flanges 81 to maintain the driver 5'; and the toggle link 55 in assembled relation. The opposite end of each wing 88 is formed with a knife edge 98 shaped to be received in a recess formed on the sides 58 of the anchor 52 to define a pivotal connection 55. Tabs or shoulders 9'! disposed outwardly from the knife edges 90 are disposed in notches 58 formed at the upper ends of the sides 58. The above construction prevents transverse movement of the driver with respect to the toggle link and the anchor after assembly of the parts and facilitates alignment of the parts during assembly of the spring. The end portion of the driver 51' terminates in an upstanding flange 99.

When the actuator 53, the toggle link 55, the coil spring 54 and the driver 5! are mounted as shown in Fig. 2 the parts are stressed to define a double snap acting spring system. The latter is drivingly connected with the leaf springs 29 through a connection as best seen in Figs. 4 and 10, the connection including an inverted T- shaped member I62 of insulating material. The stem of the T-shaped member M2 is pivotally connected on the flange 99 as by a rivet I03 and the arms I04 extend outwardly from the stem to define shoulders I66 engageable with the bottom sides of the leaf springs 29. Pivotally mounted on the flange 93 in side by side relation with the T-shaped member I62 is a member M? of insulating material having its bottom edge in substantially spaced parallel relation to the arms I M and spaced therefrom to define shoulders I68 engageable with the top side of the leaf springs as shown in Fig. 10. The rivet H3 also pivotally supports the member Hi7 on the flange 99.

The operation of the double pole double throw switch is as follows: Assuming that the switch parts are in a position shown in Fig. 4, which may be considered the normal position for the switch, the shoulders i0 3 then engage the top side of the leaf springs 29 and. urge the mobile contacts 2| into engagement with the lower fixed contacts 37. The spring system is biased so that the mobile contacts 2| are urged into engagement with the contacts 37 with a positive pressure.

The pivotal connection between the flange 99 and the member I02 insures that the pressure between each mobile contact 2| and its associated fixed contact 31 is approximately uniform. When the plunger 23 is depressed the actuator 53 is moved about the pivotal connections H and the pivotal connection 14 is moved through a plane definedby the pivotal connection 92 and the pivotal connection 86. The position of the parts with respect to each other just prior to movement of the pivotal connection 14 through the above described plane is shown in Fig. 6. As soon as the pivotal connection 14 passes through the above described plane the bridging portion 15 of the toggle 56 is caused to move between the stops 6| and 82 with a snap action. As the bridging portion 16 moves between the stops it moves the pivotal connection 86 through a plane defined by the pivotal connection 92 and the pivotal connection 96. As soon as the pivotal connection 86 passes through this plane the free end of the driver 51 is moved between its opposed positions with a snap action. Thus the snap movement of the bridging portion 16 between the stops 0I and 82 effects snap movement of the free end of the driver between opposed positions. When the free end of the driver moves between its opposed positions the shoulders I08 are moved out of engagement with the top side of the leaf springs 29 and the shoulders I06 are moved relative to the leaf springs 29 and engage the latter. Until movement of the driver 51 occurs, positive pressure is applied by the shoulders I08 on the leaf springs 20 so that the mobile contacts 2| are urged into engagement with the contacts 31. As soon as the shoulders I06 start to move the resiliency of the springs 29 also causes the contacts 2| to move away from the contacts 31. This resiliency of the leaf springs 29 and the force applied by the driving spring system effects the breaking of welds in the event such should form between the contacts 2| and 31. movement of the driver 51 the snap spring system is stressed so that the shoulders I06 engage the bottom sides of the leaf springs 29 and urge the mobile contacts 2| into engagement with the contacts 36 with a positive pressure. The pivotal'mounting of the inverted T-shaped member I02 insures that the pressure between each mobile contact 2I and its associated fixed contact 36 is substantially uniform. It is to be understood that Where desired the shoulders I06 and the shoulders I68 may be in closely spaced relation so as to engage the leaf springs 29 in both positions of the latter. In this instance there would be no lost motion between the shoulders on the leaf springs as is the case for the construction described hereinbefore.

When the force on the plunger 23 is released the pivotal connection 14 passes through a plane defined by the pivotal connections 86 and the pivotal connection 92. When this occurs the bridging portion 15 of the toggle moves between the stops BI and 82 with a snap movement. As the bridging portion 16 moves between the stops, the toggle member carries the pivotal connection 86 through a plane defined by the

pivotal connections

92 and 96 and as a result the free end of the driver is moved between its opposed positions with a snap motion. At it moves the shoulders I06 are moved out of engagement with the leaf springs 29 and the shoulders I06 move into engagement therewith. During this move ment of the shoulders, the springs 29 are urged At the conclusion of the 6. away from the contact 36 due to the resiliency of the springs. At the conclusion of the snap movement of the driving member 51 the mobile contacts 2I are forced into engagement with the contacts 31 as described hereinbefore. The opposed positions of the driver described herein are determined by engagement of the mobile contacts 2| with the contacts 36 and 31 respectively. -The above construction is extremely simple, and the parts may be formed as metal stampings. Also the parts are of such shape and configuration that they can be readily assembled. The size and shape of the spring system is such that it can be disposed in a housing having the same as the dimensions as a standard snap action precision switch. This construction provides for uniform contact pressure, breaking of welds and the maintenance of positive pressure on the contacts until snap action of the movable contacts occurs. This construction also minimizes the tendency of the switch contacts to bounce upon moving into engagement with the fixed contacts.

I claim: 1. In a snap acting-device, the combination of a base, a plurality of pairs of spaced stops mounted on said base, a pair of flexible leaf springs, each spring having an end free to move between one of said pairs of stops, means on said base for supporting the opposite end of each leaf spring to provide a cantilever mounting therefor, a double snap acting spring system mounted on said base adjacent the free ends of said leaf springs, said double snap acting spring system comprising two snap mechanisms operatively interconnected so that the snap action of the first snap mechanism effects a successive snap action operation of the second snap mechanism between opposed positions a driving connection between said second snap mechanism of the double snap acting spring system and the free ends of each of said leaf springs for moving said free ends simultaneously between said stops, said double snap acting spring system in each position of said second snap mechanism being stressed to urge said leaf springs into engagement with their respective stops with a positive pressure until the instant of movement of said second snap mechanism of the double snap acting spring system between its opposed positions, and means for actuating said first snap mechanism of the double snap spring system to effect movement of said free ends of the leaf springs between said stops.

" 2. In a snap acting device, the combination of a base, a plurality of sets of spaced stops mounted on said base, a cantilever mounted contact carrier'movable between each pair of said sets of stops and biased to be out of engagement with either adjacent spaced stop, a double snap acting spring system mounted on said base in end to end relation with said contact carriers, said double snap acting spring system comprising two snap mechanisms operatively interconnected so that the snap action of the first snap mechanism effects a successive snap action operation of the second snap mechanism between opposed positions, a lost motion driving connection between said second snap mechanism of the double snap acting spring system and the free end of each of said contact carriers including a pair of spaced shoulders engageable with each of. sai'd'contact carriers, said double snap acting spring system in each position of said second snap mechanism being stressed to urge one shoulder of each pair into engagement with its respective contact carrier to force the latter into engagement with one of its associated stops with a positive pressure until the instant of movement of said second snap mechanism of the double snap acting spring sys-- tem between its opposed positions and upon limited relative movement of said second snap mechanism of the double snap acting spring system, said other shoulder of each pair being engageable with the associated contact carrier, and means for actuating said first snap mechanism of the double snap spring system to effect simultaneous movement of said contact carriers between said stops.

3. In a double pole double throw switch, the combination of a base, a plurality of pairs of opposed contacts mounted on said base, a pair of elongated flexible contact carriers mounted in side by side coplanar relation and each having an end portion movable between one of said pairs of opposed contacts, a mobile contact mounted on each of said end portions, means for mounting the opposite ends of theicontact carriers on said base in cantilever fashion, said contact carriers being biased to urge the mobile contacts out of engagement with the respective opposed contacts, a double snap acting spring system mounted on said base adjacent the movable end portions of said contact carriers, said double snap acting spring system comprising two snap mechanisms operatively interconnected so that the snap action of the first snap mechanism effects a successive snap action operation of the second snap mechanism, a member connected to said second snap mechanism of the double snap acting spring system and movable between opposed positions with a snap action upon said snap action of the second snap mechanism of the double snap acting spring system, pairs of pivotally mounted spaced shoulders on said movable member engageable with the movable end portion of each contact carrier, said double snap acting spring system being stressed to have a shoulder of each pair engageable with one of said contact carriers in each position of the member to urge the associated movable contact into engagement with opposed contact with a positive pressure until movement of the movable member occurs, and means for actuating said first snap mechanism of the double snap acting spring system to effect movement of said member.

4. In a double pole double throw switch, the combination of a, base, a plurality of pairs of opposed contacts mounted on said base, a pair of elongated flexible contact carriers mounted in side by side coplanar relation and each having an end portion, a mobile contact mounted on each end portion and movable between one of said pairs of opposed contacts, said contact carriers being biased to urge each mobile contact out of engagement with either of the adjacent opposed contacts, means for mounting the opposite ends of the contact carriers on said base in cantilever fashion, a double snap acting spring system mounted on said base adjacent the end portion of said contact carrier, said double snap acting spring system comprising two snap mechanisms operatively interconnected so that the snap action of the first snap mechanismefiects a successive snap action operation of the second snap mechanism, a member connected to said second snap mechanism of the double snap acting spring system and movable between opposed positions with a snap action upon said snap action of the second snap mechanism of the double snap acting spring system, pivotally mounted spaced shoulders on said movable member engageable with the end portion of each contact carrier, said double snap acting spring system in each position of said member being stressed to urge said movable contacts into engagement with the opposed contacts with a positive pressure until movement of the movable member occurs, said pivotally mounted shoulders providing for uniform pressure between the mobile contacts and the opposed contacts in each position of said member, and means for actuating said first snap mechanism of the double snap acting spring system to move said member to effect simultaneous movement of the mobile contacts between the opposed contacts.

5. In a snap acting device, the combination of a base, a bracket mounted on said base, an anchor mounted on said base, spaced cantilever mounted contact carriers each having an end in spaced relation to said anchor and free to move between opposed positions, a driver pivotally supported on the anchor and having an end portion free to move between opposed positions with snap action, a, driving connection between said end portion and said contact carriers to move the latter, a toggle link in spaced face to face relation with said driver and having a pivotal con nection with said free end portion of the driver, said toggle link having a portion movable between preselected positions on opposite sides of a first plane defined by the pivotal connection between the driver and the toggle link and the pivotal connection between the driver and the anchor, spaced stops mounted on said base and engageable with said toggle link to limit movement of said portion between said preselected positions, resilient means pivotally connected with said portion of the toggle link and having an end free to move between opposed positions on opposite sides of a second plane defined by the pivotal connection between the driver and the toggle link and the pivotal connection between said portion of the toggle link and the resilient means, an actuator pivotally mounted on the bracket and pivotally connected with said free end of the resilient means and means engageable with the actuator for moving it to move said pivotal connection between the actuator and the resilient means through the second plane to move said portion of the toggle link through the first plane to effect simultaneous movement of the free ends of said contact carriers between said opposed positions.

6. In a snap acting device, the combination of a support, a bracket mounted on said support, an anchor mounted on said support, spaced coplanar contact carriers, means for mounting each contact carrier to have an end in spaced relation to the anchor and free to move between opposed positions, a driver supported on the anchor and having an end portion extending away from said anchor, said end portion being free to move between opposed positions with a snap action and interconnected with said contact carriers to move the latter, a toggle link in spaced face to face relation with said driver and interconnected with said free end portion of the driver, said toggle link having a movable end, a compression spring interconnected with the free end of the toggle link, stop means engage... able with said toggle link to limit movement of the pivotal connection between the toggle and the compression spring between positions on opposite sides of a plane defined by the pivotal connection between the driver and the toggle link and the pivotal connection between the driver and the anchor, an actuator supported on said bracket and interconnected with the compression spring and free to move the pivotal connection between the actuator and the compression spring between positions on opposite sides of a plane defined by the pivotal connection between the driver and the toggle link and the pivotal connection between the toggle link and the compression spring and means engageable with the actuator for moving it to move the pivotal connection between said actuator and the compression spring through the second plane to move the pivotal connection between the compression spring and the toggle through the first plane to eifect simultaneous movement of the free ends of said contact carriers between said opposed positions with a snap action.

'7. In a snap acting device, the combination of a base, a bracket mounted on said base, an anchor mounted on the base, a driver pivotally supported on the anchor and having an end portion free to move between opposed positions with snap action, a toggle link in side by side relation with said driver, said toggle link being pivotally connected with said free end portion of the driver and having a movable end, a compression spring pivotally connected with the free end of the toggle link and having a movable end, means engageable with the toggle link for limiting movement of the pivotal connection between the toggle link and the compression spring between positions on opposite sides of a first plane defined by the pivotal connection between the driver and the toggle link and the pivotal connection between the driver and the anchor, an actuator in side by side relation with the toggle link and pivotally supported on the bracket, said actuator having an end pivotally connected with said movable end of the compression spring and free to move the pivotal connection between the actuator and the compression spring between positions on opposite sides of a second plane defined by the pivotal connection between the driver and the toggle link and the pivotal connection between the toggle link and the compression spring and means engageable with the actuator for moving it to move the pivotal connection between the actuator and the compression spring through the second plane to move the pivotal connection, between the compression spring and the toggle link through the first plane to efiect movement of the free end portion of the driver between said opposed positions.

8. In a multi pole double throw switch, the combination of a support, a plurality of pairs of spaced contacts mounted on said support, spaced resilient leaf springs each carrying a movable contact, means for mounting each spring with said movable contact-associated therewith free to move between one of said pairs of spaced contacts, an anchor mounted on the support and spaced from said spaced contacts, a bracket mounted on said support, a driver pivotally mounted on the anchor and having an end portion adjacent said spaced contacts and free to move between opposed positions with a snap action, a lost motion driving connection between said ,free end portion and each of said leaf springs, a toggle link in side by side relation with said driver and pivotally connected with said free end portion of thedriver, said toggle link having a portion movable between opposed positions on opposite sides of a first plane deand the pivotal connection between said portion of the toggle link and the compression spring, an actuator pivotally mounted-Yon the bracket and having an end pivotally connected with said free end of the compression spring and means engageable with said actuator for moving it to move said free end of the compression spring across the second plane tov move said portion of the toggle link across the first plane to eiTect a snap movement of said movable contacts between said spaced cont-acts through said connection.

9. In asnap acting device, the combination of a base, spaced stop means mounted on saidv base, a rigid upstanding bracket mounted on said base, a rigid anchor'disposed between said" stop meansand the bracket, a rigid driver pivotally mounted on said anchor and having an endfree to move, means. acting between said stop means and said free end for limiting movement thereof between opposed positions, a rigid toggle I link in side by side relation with said driver and having a pivotal connection with said free end of the driver, said toggle link having a movable end, 'a resilient coil spring having a pivotal con-- nection with the free end of the toggle link and having a movable end, spaced stop means engageable with said toggle link to limit movement of the pivotal connection between the toggle link and the coil spring between positions on opposite sides of the first plane defined by the pivotal connection between the driver and the toggle link and the pivotal connection between the, driver and the anchor, a rigid actuator pivotally supported on said bracket and pivotally connected with the movable end of the coil spring and free to move the pivotal connection between the actuator and the coil spring'between positions on opposite sides of asecond plane defined by the pivotal connection between the driver and the toggle link and the pivotal connection between the toggle link and the coil spring and means engageable with said actuator to move the pivotal connection between the ac-v tuator and the coil spring through the second plane to efiect movement of the pivotal connection between the toggle'link and the coil spring through the first plane to effect movement of the free end of the driver between said opposed positions with a snap action, said driver in either of its opposed positions applying a positive pressure on said stop means until snap movement occurs.

10. In a snap acting device, the combination of a support, a bracket mounted on said support, an anchor mounted on said support, a driver pivotally supported on the anchor and having an end portion free to move between 0p-. posed positions with snap action, means acting between said anchor and said driver forholding the latter against movement transversely of the anchor, a toggle link in side by side relation with said driver, said toggle link being pivotally connected with said end portion of the driver-and having a movable end, resilient meanspivotally connection between the driver and the toggle link and the pivotal connection between the driver and the anchor, means acting between said toggle link and said driver for preventing. movement of said toggle link transversely of the driver, an actuator pivotally supported on said bracket and pivotally connected with said movable end of the resilient means and free to move the pivotal connection between the actuator and the resilient means between positions. on op.-. posite. sides of a second plane. defined by the pivotal connection between the driver; and the toggle link and the pivotal connection between the toggle link and the resilient means, means. acting between the actuator and. the bracket tor holding the actuator against movement trans versely of. the bracket and means engageable with said actuator for moving it to move the. pivotal connection between the'actuator and the resilient. means through the second: plane to. move the pivotal connection between the. re.-. silient means and. the toggle link through the first plane to effect snap. movement. of the end portion of said driver between said opposed positions.

1,1. In a snap. acting device, the combination of a support, an upstanding bracket having an. aperture, an anchor having spaced. pivotal recesses facing. away from said bracket, a. driver having an end-portion free tomove between. op.- posed positions and having spaced wings interconnectedwith said end porti'o'n' and defining the sides of said driver, each of saidwings having a knife edge shaped to be received in one of said pivotal, recesses on saidanchor and having. a knife edge facing away from said anchor, means acting between each. wing and-the anchor for maintain.- ing said driverin assembled relation with. the anchor, a. toggle link comprising. agenerall'y. U- shap'edamember having spaced legsand a' bridging. portion, each of said legs having a recess shaped to receive: the knife edge on the wings facing away from, the anchor, sai'd' movable bridging portion shaped to be receivedin' said aperture, a compression spring pivotally. connected with said. bridging portion and ha-ving a movable. end,- stops, one of'which is defined by one of: the side. walls of. the aperture, positioned to; beengageable by said bridging portion to limit movement of the pivotal connection between thebri'dging portion and the compression. spring between position's on opposit sides of a first plane definedby the. pivotal connectionbetweenthe driver andthe legs and the pivotal support. between the driver. and the anchor,. means acting between each wing andiits associated leg for-holding-..said toggle link and said driver in assembled relation, an actuator pivotally' mounted. on. said bracket and having an end shaped to. pass between thelegs ofsaidtoggle linkand to be pivotally. connected with saidimovable endi-of'the' compression spring and free to move. said pivotal connection between said actuator and the-compression spring between positions on opposite sides of a second plane defined by the pivotal connection between the driver and the legs and the pivotaliconnection between thebridging portionandLthe compression.

spring, means acting 4 between saidflbracket. and opposite sides of the actuator to maintain-the actuator in assembled relation and means en: gageable with said actuator to move said pivotal connection between the actuator and the compression spring through the second plane to move the pivotal connection between the compression spring and the bridging portion through the first plane to efiect movement of the; free end portion of the driver between said opposed positions.

12. In a snap acting device, the combination of a base, an upstanding bracket having an aperture and spaced sides on opposite sides of the bracket, said sides each having aninwardly facing recess; an anchor having spaced upstanding sides each having an outwardly facing notch at the extreme upper end ofthe side and a recess facing in a direction away from the bracket; a driver having an end free tomove-between opposed positions with a snap action and having wings interconnected with said end portion disposed onopposite sides thereof; one end of each wing having a knife edge shaped to be received in the recesson said sides of the anchor and having ashoulder portion shaped to be received in saidnotch, the opposite end; ofeach of said wings being; formed wi-tha knife edge facingaway from said anchor, a toggle link comprising a generally U- shaped member having spacedlegs and a bridging portion, eachof said legs having its outer end formed with a flange, each of said'flangeshavinga recess shaped to receiveone of the knife edges on said Wings facing awayfromthe anchor, said bridging portion being shaped to be received in said aperture and having a projection extending between said legs, a compression spring having an end pivot-al-l'vmountedon saidprojection and; having its opposite end disposed between said legs and free to move, spaced stops, one of which is formed, by aside wall of said aperture; en gageable with said bridging portion to limit movement of the pivotal connection between the toggle link and the compression spring between positions. on opposite sides of a first" plane defined by the knife edgeson the wings, an actuator having anendformed, with sides shapedft be received in said recesses onthe bracket andjhav- 111g ho lde n a a l t h b a ket. maintain the actuator in assembled relationwith e k t. a ect ie rhav n ts nq iie. end. shaped to pass betweenthe legs of the-to gle link and-having a projection shaped to be pivotally connectedwith the movable: end of the compres' sion spring and; free, to move thepivotal connec-. tion between the: actuator the compression spring-on opposites ifld es;o f a second plane defined, by the knife edges on said wings facing away from theanchor and" the pivotalconnection be tweenthe compression spring and the toggle link, and a plunger engageable. with said actuator to move saidpivotal-connection between the actu ator and the compression spring through said? second plane to move the pivotal connection be tween se link ha empr ions ri through; the first' plane to effect successive snap} movements of the bridging: portion of the toggle link and the; free end portion ofthe driver,

13% In a spa-p acting device; in combination, a base, apairof'spaced stops fixedly mounted on said-base, acontact carrier-movable between said stops, a- -doubiesnap acting spring system comprising two snap mechanisms operatively interconnected sothat the snap actionof the first snaptmechanism effects a successive-snap-actienoperation. of the second snap mechanismbe tween. spacedpcsitions, a-lost-motion driving con-- nectiombetween; saidcisecond :snan-.mecl1anism ct the double snap acting spring system and the contact carrier for moving said contact carrier between the spaced stops with a snap action, said double snap acting spring system in each of the spaced positions of said second snap mechanism thereof being stressed to exert a'positive pressure against the contact carrier to urge the. same into.

engagement with the respective stop until :the instant of movement of said second snap mechanism of thedouble snap acting spring system between its positions, and means foractuating said first snap mechanism of the double snap acting spring system to effect movement of the contact carrier between said stops.

14. In a snap acting device, in combination, a base, a pair of spaced stops fixedly mounted on said base, a contact carrier movable between said stops and biased to be out of engagement with either of said stops, a double snap acting spring system comprising two snap mechanisms operatively interconnected so that the snap action ofthe first snap mechanism effects a successive snap action operation of the second snap mechanism between spaced positions, a driving connection between said second snap mechanism of the double snap acting -spring system and the contact carrier for moving said contact,

carrier between the spaced stops with a snap action, said double snap acting spring system in each of the spaced positions of said second snap mechanism thereof being stressed to exert a positive pressure against the contact carrier to urge the same into engagement with the respective stop until the instant of movement of said second snap mechanism of the double snap acting spring system between its positions, and means for actuating said first snap mechanism of the double snap acting spring system to effect movement of the contact carrier between said stops.

15. In a snap acting device, in combination, a base, a pair of opposed spaced stops fixedly mounted on said base, a contact carrier movable between said stops and resiliently biased to be out of engagement with either of said stops, a double snap acting spring system mounted on said base, said double snap acting spring system comprising two snap mechanisms operatively interconnected so that the snap action of the first snap mechanism effects a successive snap action operation of the second snap mechanism between opposed spaced positions, a driving connection between said second snap mechanism of the double snap acting spring system and the contact carrier for effecting movement of said contact carrier between the spaced stops with a snap action, said double snap acting spring system in each of the opposed positions of said second snap mechanism thereof being stressed to exert a positive pressure against the contact carrier to urge the same into engagement with the respective stop until the instant of movement of said second snap mechanism of the double snap acting spring system from one of its opposed positions to the other, and means for actuating said first snap mechanism of the double snap acting spring system to effect movement of said second snap mechanism of the double snap acting spring system between its opposed positions to thereby move the contact carrier from one of the opposed fixed stops to the other.

16. In a snap acting device, in combination, a base, a pair of opposed spaced stops fixedly mounted on said base, a flexible leaf spring having an end free to move between said stops, means on said base supporting the other end of said leaf spring to provide a cantilever mounting therefor, a double snap acting spring system mounted on said base, said double snap acting spring system comprising two snap mechanisms operatively interconnected so that the snap action of the first snap mechanism effects a successive snap action operation ofthe second snap mechanism between opposed positions, a driving connection between said second snap mechanism of the double snap acting spring system and the free end of the leaf spring for moving said free end between the opposed stops with a snap action, said double snap acting spring system in each position of said second snap mechanism thereof being stressed to exert a positive pressure to urge the leaf spring into engagement with the respective stop until the instant of movement of said second snap mechanism of the double snap acting spring system between its opposed positions, and means for actuating said first snap mechanism of the double snap acting spring sys-.

tem to effect movement of the free end of the leaf spring between said stops.

i 17. In a snap acting device, in combination, a base, a pair of opposed spaced stops fixedly mounted on said base, a flexible resilient leaf spring having an end free to move between said stops, means on said base supporting the other end of saidleaf spring to provide a' cantilever mounting therefor, said leaf spring being biased to urge its free end away from engagement with either of the opposed stops, a double snap acting spring-system mounted on said base, said double snap acting spring system comprising two snap mechanisms operatively interconnected so that the snap action of the first snap mechanism effects a successive snap action operation of the second snap mechanism between opposed positions, a driving connection between said second snap mechanism of the double snap acting spring system and the free end of the leaf spring for moving said free end between the opposed stops with a snap action, said double acting snap spring system in each position of said second snap mechanism thereof being stressed to exert a positive pressure to urge the leaf spring into engagement with the respective stop until the instant of movement of said second snap mechanism between its opposed positions, and means for actuating said first snap mechanism of the double snap acting spring system to effect movement of the free end of the leaf spring between said stops.

18. In a snap acting device, in combination, a base, a pair of opposed spaced contacts fixedly mounted on said base, a cantilever mounted leaf spring mounted on said base and having an end free to move between said opposed fixed contacts, a mobile contact mounted on said leaf spring adjacent the free end thereof to be movable for alternate engagement with one or the other of said fixed contacts, said leaf spring being biased to urge the mobile contact out of engagement with either of the opposed fixed contacts, a double snap acting spring system mounted on said base, said double snap acting spring system comprising two snap mechanisms operatively interconnected so that the snap action of the first snap mechanism effects a successive snap action operation of the second snap mechanism movable between opposed positions, a driving connection between said second snap mechanism of the double snap acting spring system and the gamma free endof the leaf spring for movingthe mobile contact between the opposed fixed contacts with a snap action, said double snap acting spring system in either position of said second snap mechanism thereof being stressed to exert a positive pressure against the freeend of the leaf spring to urge the mobile contact into engagement with the respective fixed contact until the instant of movement of said second snap mecha nism of the double snap acting spring system to its other position, and means for actuating said first snap mechanism of the double snapacting spring system to effect movement of said secand snap mechanism of the double snap actingspring system between its opposed positions to thereby move the contact carrier from engagement with one of the fixed contacts into engagement with the other fixed contact.

19. In a snap acting device, in combination, a base, a pair of opposed spaced contacts fixedly mounted on said base, a cantilever leaf spring mounted at one end on said base and having its other end free to move between said fixed contacts, a mobile contact mounted on said leaf spring adjacent the. free end thereof to be movable for alternate engagement with one or the other of said fixed contacts, said cantilever leaf spring being biased to urge the mobile contactout of engagement with either 01' the fixedcontacts, a double snap acting. springsystem mounted on said base comprising two snap: mechanisms operatively interconnected so that the snap action of the first. snap mechanism effects a suecessive snap action operation of the second snap mechanism, said second snap mechanism of the 16 double snap acting spring system having an end adjacent the tree end of the cantilever leaf spring free to"- move between opposed positions with a snap action, a member pivotally mounted on said end at said second snap mechanism of the double snap actmg spring system for movement between said opposed positions and engageable with the free end of the cantilever leaf spring for moving the mobile contact between the opposed fixed contacts with a snap action, said double snap acting spring system in either opposed position of said movable member being stressed to exert a positive pressure against the free end of the cantilever leaf spring to urge the mobile contact into engagement with the respective fixed contact until the instant of movementof said movable member to its other opposed position, and means for actuating said first snap mechanism of the double snap acting spring system to effect movement of the mobile contact between said fixed contacts.

VVILBERT A. MARTIN.

References Cited in the file of this patent UNITED STATES PATENTS