US3715534A

US3715534A - Miniature multi-pole toggle switch with momentary action

Info

Publication number: US3715534A
Application number: US00167964A
Authority: US
Inventors: E Piber
Original assignee: Cutler Hammer Inc
Current assignee: Cutler Hammer Inc
Priority date: 1971-08-02
Filing date: 1971-08-02
Publication date: 1973-02-06
Anticipated expiration: 1990-02-06

Abstract

Three and four pole toggle switches. Miniature size is attained by providing springs affording contact pressure that require a minimum of space and by providing momentary action spring structure that can be incorporated in the same dimensional housing as used for the non-momentary action switches.

Description

United States Patent [191 Piber 1 Feb. 6, 1973 I541 MINIATURE MULTI-POLE TOGGLE SWITCH WITH MOMENTARY ACTION [75 Inventor: Earl T. Piber, Oconomowic, Wis.

[73] Assignee: Cutler-Hammer Inc., Milwaukee,

. Wis.

[21] Appl. No.: 167,964

[52] US. Cl ..200/67 G, 200/68 [51] Int. Cl. ..H0lh 13/28 [58] Field of Search ..200/67 G, 133 K, 68

[56] References Cited UNITED STATES PATENTS 2,248,362 7/1941 Krieger ..200/68 3,482,067 12/1969 Sanford ..200/67 G 2,759,075 8/1956 Hults ..2001153 R 3,350,521 10/1967 Brown ..200/67 G Primary Examiner-David Smith, Jr. Att0rneyl-lugh R. Rather et a].

[57] ABSTRACT Three and four pole toggle switches. Miniature size is attained by providing springs affording contact pressure that require a minimum of space and by providing momentary action spring structure that can be incorporated in the same dimensional housing as used for the non-momentary action switches.

10 Claims, 10 Drawing Figures PATENTEDFEB 6|973 3,715,534

SHEET NF 3 PATENTEDFEB 6 197a SHEET 30F 3 Invantvr Barf 1'. Pz'ber y .fhtornoy MINIATURE MULTI-POLE TOGGLE SWITCH WITH MOMENTARY ACTION BACKGROUND OF THE INVENTION Momentary action switches have been known heretofore. Generally, momentary switch action has been attained by use of compression springs or the like for returning the switch actuator back to its original position. Torsion springs positioned around the pivot pin of a toggle lever or between the toggle lever and the housing have also been used for this purpose. In addition, a helical spring looped around the toggle lever has been used to provide one-way momentary action. Moreover, in some prior switches, the contacts have been shaped so as to cause sliding return of the actuator to its unactuated position.

Proper contact pressure has generally been attained in three and four-pole toggle switches by providing individual spring biased plungers for the respective poles of the switches.

These prior art structures have had the disadvantage of requiring greater-overall switch dimensions.

SUMMARY OF THE INVENTION This invention relates to miniature multi-pole toggle switches having provision for proper contact pressures and. momentary action without increasing the overall size of the switch.

An object of the invention is to provide an improved multi-pole toggle switch of a miniature size.

Another object of the invention is to provide a toggle switch of three or more poles with improved contact pressure means.

Another object of the invention is to provide a toggle switch of three or more poles with improved momentary action means.

Other objects and advantages of the invention will hereinafter appear.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an enlarged isometric ,view of a miniature three-pole toggle switch with provision for one or two way momentary action constructed in accordance with the invention;

FIG. 2 is a further enlarged lateral center line crosssectional view of the switch of FIG. 1;

FIG. 3 is a longitudinal center line cross-sectional view of the switch of FIG. 2;

FIG. 4 is an exploded isometric view of the upper portion of the switch of FIGS. 1-3;

FIG. 5 is an exploded isometric view of the lower portion of the switch of FIGS. l-3;

FIG. 6 is an enlarged isometric view of a miniature four-pole toggle switch with two way momentary action constructed in accordance with the invention;

FIG. 7 is a further enlarged lateral center line crosssectional view of the switch of FIG. 6;

FIG. 8 is a longitudinal center line cross-sectional view of the switch of FIG. 7;

FIG. 9 is an exploded isometric view of the switch of FIGS. 6-8; and

FIG. 10 is a fragmentary view showing a modification I of the switch of FIGS. 6-9 for one way momentary ac- IIOII.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. 1, there is shown a toggle switch having an insulating base 2, a metal frame 4 closing the top of the base and having an upstanding bushing 4a, and a toggle lever 6 pivotally mounted in the bushing for actuating the switch. Base 2 comprises two adjacent center sections 2a and 2b and two

opposite end sections

26 and 2d as shown in FIGS. 1 and 5. These base sections have interfitting locking portions whereby they are held in position with respect to one another and clamped by the frame to provide a compartment for the switch contacts. Stationary contacts are mounted within the base and clamped between the base sections with their terminals extending to the exterior through the bottom. These terminals comprises three center terminals 8, three terminals 10 for connection to the respective center terminals on a first throw of the toggle lever, and three terminals 12 for connection to the respective center terminals on a second throw of the toggle lever.

As shown in the further enlarged transverse center line cross-sectional view in FIG. 2, the toggle lever is provided with an enlarged portion 6a having partially spherical shaped upper sides bearing against a constricted portion at the upper end of the bore in the bushing to provide a seat for limited pivotal movement of the toggle lever, the toggle lever being biased upwardly against this constriction in the bushing by springs therebelow as hereinafter described.

The three stationary contacts 8a in the middle row are each provided with an integral cradle shown in FIG. 5 for rockably supporting a movable contact 14 capable of being rocked into engagement with either stationary contact 10a or by an operator hereinafter described.

The contact operator comprises an elongated actuator 16 of insulating material having a vertical hole at its center as shown in FIGS. 2-4 and a triangular runner 16b at each end. These runners run on the left and right movable contacts as shown in FIG. 3 and a plunger 18 extends through its center hole and has an enlarged lower end 18a that runs or slides on the center movable contact as shown in FIG. 2. The movable contacts 14 each being a metal strip with the two halves bent slightly up at the middle, sliding of the runners or plunger thereon toward the left in FIG. 2 causes the left half thereof to bridge

contacts

8a and 10a. Similar sliding toward the right causes the right-half thereof to bridge

contacts

8a and 12a. In the center off position, the movable contact is biased within the cradle in the center stationary contact and is open with respect to the other two stationary contacts. The movable contact has a pair of opposite arms 14a at itscenter as shown in FIG. 5 to retain it within the cradle. Contact actuator 16 is provided with a pair of transverse grooves 16c, shown in FIG. 4, on its upper surface near its ends which grooves provide clearance in its movement for a pair of guide brackets hereinafter described.

The contact operator additionally comprises a spring biased plunger 20 for biasing actuating 16 down against the left and right movable contacts. For this purpose, the toggle lever is provided with a bore into which a helical compression spring 22 is first inserted followed by plunger 20. Plunger 18 is biased against the center is biased by spring 24 against the center movable contact. In this manner, proper contact pressure is applied to all three contacts and the pressure applying means of any two contacts does not relieve the pressure on the third contact as might be the case if a single rigid actuator were used for all three contacts.

The switch is also provided with one or two way momentary operation. Momentary operation means automatic return to off when a toggle lever is released after actuation. For this purpose, a pair of torsion springs 26 are provided and one or both can be used in assembly to provide one way or two way momentary operation, respectively.

This torsion spring 26 comprises a wire having a one turn loop at its center through which plunger is inserted so that these torsion springs rest in stacked relation on top of actuator 16. The ends of these torsion springs are inserted in and held in notches 28a in guide brackets 28 welded within the top of the frame spaced from the ends thereof as shown in FIG. 4. Each guide bracket has a downwardly-bent part into which such notch is made. The lower edge 28b of this part is curved as shown in FIG. 4 to clear the actuator in its motion.

Each torsion spring 26 is placed on the plunger so that one torsion spring is wound up more when the toggle lever ispivoted in one direction and the other torsion spring is wound up more when the toggle lever is pivoted in the other direction. In each case, the torsion spring primarily concerned returns the toggle lever to the center when it is released. One torsion spring is omitted in assembly if only one way momentary is desired.

To insulate the guide brackets, and consequently the frame, from the contacts, and to provide anti-friction guiding of actuator 16 in its reciprocable movements, a pair of insulator plates 30 of mylar or the like reduced friction material are placed between the ends of the actuator and the guide brackets. As shown in FIG. 4 these insulator plates have a central notch 30a in their lower edge to clear center stationary contact 8 as shown in FIGS. 2 and 3. Also, the guide brackets each havea relatively wider central notch 28c in their lower edge to provide electrical clearance or lengthen the electrical. path between it and the center stationary contact around notch 30a of the insulating plate. These mylar" plates reduce the friction that would otherwise exist between the phenolic actuator and the metal guidebrackets.

A four-pole double-throw toggle switch is shown in FIG. 6. As shown therein, the switch comprises an insulating base 32, a metal frame 34 closing the top of the base and having an upstanding bushing 34a, and a toggle lever 36 pivotally mounted within the bushing for actuating the switch. Base 32 comprises three adjacent center sections 32a, 32b and 32c and two opposite end sections 32d and 322 as shown in FIGS. 6 and 9. These base sections have interfitting locking portions whereby they are held in registration with respect to one another and clamped by the frame to provide a compartment for the switch contacts. Stationary contacts are mounted within the base and clamped between the base sections with their terminals extending to the exterior through the bottom. These terminals comprise four center terminals 38, four terminals 40 for connection to the respective center terminals on a first throw of the toggle lever, and four terminals 42 for connection to the respective center terminals on a second throw of the toggle lever.

As shown in the further enlarged transverse center line cross-sectional view in FIG. 7, the toggle lever is provided with an enlarged portion 36a formingwith a constriction at the upper end of the bushing bore a pivotal support for the toggle lever, the toggle lever being biased against this constriction by springs therebelow as hereinafter described.

The

stationary contacts

38a, 40a and 42a and movable contacts 44 are like those hereinbefore described except that there are four sets instead of three.

The contact operator, as shown in FIGS. 7-9, comprises an elongated actuator 46 of insulating material such as phenolic having a vertical hole 46a atits center for receiving the reduced diameter lower end portion 48a of a spring-biased plunger 48. Actuator 46 also has a triangular runner 46b at each end. These runners run on the left and right movable contacts as shown in FIG. 8. Actuator 46 also has a pair of vertical, square holes 46c equally spaced on opposite sides of its center hole as shown in FIG. 9. A pair of plungers 50 extend up through these holes above the upper surface of the actuator. For biasing these two square plungers downwardly against the two center movable contacts, there is provided a leaf spring 52 shown in FIG. 9. This leaf spring is provided with a hole 52a at its center through which reduced end portion 48a of plunger 48 extends. Thus, the shoulder above this reduced end portion presses the leaf spring down and the leaf spring resiliently biases plungers 50 down onto the center two movable contacts independently of any movement of actuator 46.

Toggle lever 36 is provided with a bore into which a helical compression spring 54 is first inserted. Plunger 48 is inserted in this bore next and spring 54 applies a bias through plunger 48 and actuator 46 to the left and right end movable contacts to afford equal contact pressures, actuator 46 being arranged to be self-leveling on plunger 48. Plunger 48 also applies a bias through secondary spring 52 and square plungers 50 to the center two movable contacts, this bias being independent of the end contact bias so that no two contacts will hang up or relieve the contact pressure on a third contact.

Actuator 46 is also provided with a pair of transverse grooves 46d, shown in FIG. 9, on its upper surface near its ends to clear a pair of guide brackets hereinafter described.

This four-pole switch is also provided with one or two way momentary operation. For this purpose, a straight spring wire 55 shown in FIG. 8 extends through a small transverse hole in the lower end of plunger 48 just above its reduced lower end portion. The opposite ends of this wire are inserted into and held in notches 56a in guide brackets 56 welded within the top of the frame slightly spaced from the ends thereof as shown in FIG. 8. Each such guide bracket has a downwardlybent part into which such notch is made. The lower edge 56b of this downwardly-bent part is curved as shown in FIG. 9 to clear groove 46d in actuator 46 during reciprocal movement of the latter.

It will be apparent that notch 56a-is placed in the center of its bracket to provide two way momentary action. That is,-the spring effect of wire 55 will return the toggle lever back to center from either direction of l pivotal movement.

For one way momentary switch action, a guide bracket 58 as shown in FIG. 10 is provided in one end of the frame having its notch 58a extended from the center toward the front or back. it will be apparent that the guide bracket at the other end of the frame will have its notch extended in the same direction from the center as shown in dotted lines in FIG. 10 to provide clearance for spring wire 55 to move in one direction, without deflecting that is, in the non-momentary direction of actuation. This requires two different guide brackets, that is, notches extended in opposite directions so that when they are placed in position to face one another, the notches will extend in the same direction.

As in the case of the three-pole switch hereinbefore described, this four-pole switch is also provided with a pair of insulating friction-free plates 60 each'having a rectangular notch 60a to clear the center stationary contact. Also, guide brackets 56 are provided with a notch 56c for electrical clearance relative to the contacts.

While the apparatus hereinbeforedescribed is effectively adapted to fulfill the objects stated, it is to be understood that the invention is not intended to be confined to the particular preferred embodiments of miniature multi-pole toggle switches with momentary action disclosed, inasmuch as they are susceptible of various modifications without unduly departing from the scope of the appended claims.

lclaim:

l. in a multi-pole electric-switch especially adapted for miniaturization:

an insulating base;

a frame secured to said base;

stationarycontacts mounted in said base and having terminals extending to the exterior thereof for connection to an external circuit;

movable contacts seated on first stationary contacts and arranged to be rocked into engagement with others of said stationary contacts to complete elecand spring biased couplingmeans coupling said toggle lever to said first actuator and said second actuator means to apply separate forcesthereto allowing said first actuator and said second actuator meansto move relative to one another under their relative resilient forces without any hang-up therebetween.

2. The invention defined in claim 1,-wherein said actuator mechanism also comprises:

momentary action spring means having a center portion connected to said spring biased coupling means and being elongated in form;

and means fixed to said frame for anchoringthe opposite ends of said momentary action springmeans so that it will return the toggle lever after it is actuated and released.

3. The invention defined in claim 2, wherein said momentary action springmeans comprises:

a spring wire extending through a small hole in said spring biased coupling means and having its ends anchored as aforesaid for two-way momentary action.

4. The invention defined in claim 2, wherein said means fixed to said frame comprises:

one-way slots for the opposite ends of said spring wire for one-way momentary action.

5. The invention defined in claim 1, wherein said frame comprises:

a pair of guide brackets, one at each end of said first actuator means;

and a pair of low-friction insulating plates between said guide brackets and the ends of said first actuator means to guide the latter in its movement.

6. -In a multi-pole electric switch especially adapted for miniaturization:

an insulating base;

a frame secured to said base;

stationary contacts mounted in said'base and having terminals extending to the exterior thereof for connection to an external circuit;

movable contacts seated on first stationary contacts and arranged to-be rocked into engagement with others of said stationary contacts to complete electrical connections therebetween;

a toggle lever;

.means pivotally supporting said toggle lever on said frame;

and an actuator mechanism operable by said toggle lever for rockingsaid movable contacts and for applying and maintaining contact pressures between said movable and stationary contacts so'that the contact pressure on any two contacts will not rehave the contact pressure on a third-contactcomprising:

a first actuator means engagingtwo of said'movable contacts;

second actuator meansengaging atleast a third'one of said movable contacts;

and spring biased coupling means couplingsaid toggle'lever to said first and second actuator means to apply separate forces thereto, .allo-wing said first and second actuator means to move relative to one another under their relative resilient forces without any hang-up therebetween comprising:

a first spring within a bore in said'toggle lever;

a plunger in said bore biased by said first spring for applying a resilient force to said first actuator means;

and a second spring reacting against said plunger for applying a resilient force to said second actuator means thereby allowing the latter to move relative to said first actuator means.

7. The invention defined in claim 6, wherein said second spring comprises:

a helical spring within a bore in said plunger;

and said second actuator means comprises another plunger extending from within the bore in the first plunger through a hole in said first actuator means and being biased by said helical spring against the associated movable contact.

8Q The invention defined in claim 6, wherein said second spring comprises:

a leaf spring having a hole at its center;

and said plunger having a reduced end portion extending through said hole in said leaf spring into a hole in said first actuator means whereby said leaf spring is held against the latter;

and said second actuator means comprises a pair of spaced plungers extending through holes in said first actuator means under the opposite ends of said leaf spring whereby the latter resiliently biases said spaced plungers against respective movable contacts.

9. The invention defined in claim 6, wherein said actuator mechanism also comprises:

momentary action spring means having a connection at its center to said plunger;

and means restraining movement of the opposite end portions of said momentary action spring means whereby actuation of said toggle lever stresses the latter to render it effective to return said toggle lever to its unactuated position upon release.

10. The invention defined in claim 9, wherein said connection of said momentary action spring means to said plunger comprises:

a one turn loop at the center of said momentary action spring means through which said plunger extends.

Claims

1. In a multi-pole electric switch especially adapted for miniaturization: an insulating base; a frame secured to said base; stationary contacts mounted in saiD base and having terminals extending to the exterior thereof for connection to an external circuit; movable contacts seated on first stationary contacts and arranged to be rocked into engagement with others of said stationary contacts to complete electrical connections therebetween; a toggle lever; means pivotally supporting said toggle lever on said frame; and an actuator mechanism operable by said toggle lever for rocking said movable contacts and for applying and maintaining contact pressures between said movable and stationary contacts so that the contact pressure on any two contacts will not relieve the contact pressure on a third contact comprising: a first actuator engaging two of said movable contacts; second actuator means engaging at least a third one of said movable contacts; and spring biased coupling means coupling said toggle lever to said first actuator and said second actuator means to apply separate forces thereto allowing said first actuator and said second actuator means to move relative to one another under their relative resilient forces without any hang-up therebetween.

2. The invention defined in claim 1, wherein said actuator mechanism also comprises: momentary action spring means having a center portion connected to said spring biased coupling means and being elongated in form; and means fixed to said frame for anchoring the opposite ends of said momentary action spring means so that it will return the toggle lever after it is actuated and released.

3. The invention defined in claim 2, wherein said momentary action spring means comprises: a spring wire extending through a small hole in said spring biased coupling means and having its ends anchored as aforesaid for two-way momentary action.

4. The invention defined in claim 2, wherein said means fixed to said frame comprises: one-way slots for the opposite ends of said spring wire for one-way momentary action.

5. The invention defined in claim 1, wherein said frame comprises: a pair of guide brackets, one at each end of said first actuator means; and a pair of low-friction insulating plates between said guide brackets and the ends of said first actuator means to guide the latter in its movement.

6. In a multi-pole electric switch especially adapted for miniaturization: an insulating base; a frame secured to said base; stationary contacts mounted in said base and having terminals extending to the exterior thereof for connection to an external circuit; movable contacts seated on first stationary contacts and arranged to be rocked into engagement with others of said stationary contacts to complete electrical connections therebetween; a toggle lever; means pivotally supporting said toggle lever on said frame; and an actuator mechanism operable by said toggle lever for rocking said movable contacts and for applying and maintaining contact pressures between said movable and stationary contacts so that the contact pressure on any two contacts will not relieve the contact pressure on a third contact comprising: a first actuator means engaging two of said movable contacts; second actuator means engaging at least a third one of said movable contacts; and spring biased coupling means coupling said toggle lever to said first and second actuator means to apply separate forces thereto allowing said first and second actuator means to move relative to one another under their relative resilient forces without any hang-up therebetween comprising: a first spring within a bore in said toggle lever; a plunger in said bore biased by said first spring for applying a resilient force to said first actuator means; and a second spring reacting against said plunger for applying a resilient force to said second actuator means thereby allowing the latter to move relative to said first actuator means.

7. The invention defined in claim 6, wherein said second spring comprises: a helical spRing within a bore in said plunger; and said second actuator means comprises another plunger extending from within the bore in the first plunger through a hole in said first actuator means and being biased by said helical spring against the associated movable contact.

8. The invention defined in claim 6, wherein said second spring comprises: a leaf spring having a hole at its center; and said plunger having a reduced end portion extending through said hole in said leaf spring into a hole in said first actuator means whereby said leaf spring is held against the latter; and said second actuator means comprises a pair of spaced plungers extending through holes in said first actuator means under the opposite ends of said leaf spring whereby the latter resiliently biases said spaced plungers against respective movable contacts.

9. The invention defined in claim 6, wherein said actuator mechanism also comprises: momentary action spring means having a connection at its center to said plunger; and means restraining movement of the opposite end portions of said momentary action spring means whereby actuation of said toggle lever stresses the latter to render it effective to return said toggle lever to its unactuated position upon release.