US2229022A - Double throw switch - Google Patents

Description

Jan. 14, 1941. B. E. SHAW DOUBLE THROW SWITCH Filed Hay l, 1939 Patented Jan. 14, 1941 Y UNITED STATES PATENT! ori-ica DOUBLE THROW SWITCH Burton E. Shaw, Bristol, Ind., assigner to Penn Electric Switch Co., Goshen, Ind., a corpora tion o! Iowa l Application May 1, 1939, senat No. 271,122 17 claims (ci. 20o-e7) An object of my present invention is to prodevice, whereby the objects contemplated are atvide a switch structure including a switch arm tained, as hereinafter more fully set forth, pointpivotally mounted so that it can be rocked one ed out in my claims, and illustrated in the accomway for opening one set of contacts and the other panying drawing, inwhich: way for opening another set of contacts and clos- Figure 1 is a plan view of a double throw ing the first set, permanent magnets being assoswitch embodying my invention, the cover being ciated with each end of the switch arm and such omitted therefrom in order to show internal ends having armatures carried thereby for costructural details, this view being about twice action with the permanent' magnets to, provide actual size.

snap action for both sets of contacts. Figure 2 is a sectional view on the line 2-2 of 10 Another object is to provide a compact switch Figure 1 showing the cover in position. unit adaptable for carrying comparatively heavy Figure 3 is a sectional view on the line 3-3 of current loads, the switch being so constructed and Figure 2. the component parts thereof being so designed Figure 4 is a side elevation of my switch strucand arranged as to provide a minimum number ture with the cover removed and the lower` por- 15 of parts and a very compact arrangement thereof tion of the base broken away. whereby a switch structure of large capacity may Figure 5 is a sectional view on the line 5-5 of be made comparatively small in size. Figure 2. More particularly it is an object of my inven- Figure 6 is a perspective view of a bracket used tion to provide a switch unit including a base and in my switch structure. :20l

a cover therefor with three terminals mounted Figure 7 is a sectional view on the line l-l of in the base and switch mechanism mounted with- Figure 2. in the cover and comprising a stationary contact Figure 8 is a sectional view on the line 8 8 of mounted on each terminal with a pair of leaf Figure 2; and

springs carrying contacts which normally en- Figure 9 is a perspective view of a spring used 25 gage the stationary contacts, a centrally pivoted in connection with the armature of my structure switch arm being provided for disengaging the for effecting adjusting ot the armature and thereleaf spring contacts from the stationary contacts by the differential of operation of the switch and an operating pin for the switch arm extendstructure.

ing through the cover. On the accompanying drawing I have used the 30 A further object is to provide opposite ends of reference character B to indicate a base and C a the switch arm with armatures and to provide cover therefor. 'I'he cover C is provided with ina magnet for each armature, the armatures beternal bosses I0 through which screws I2 extend, ing adjustable in a novel manner relative to the the heads thereof being counter-sunk in the base switch arm for changing the differential of op-V B and the shanks of the screws extending beyond 35 eration of either set of switch contacts. Y the cover C as in Figure 2 whereby they may be A further object is to provide means to retain threaded into any suitable type of support S. the magnets in position which consists of brack- In Figure' 6 I illustrate a bracket A having a ets mounted on terminals of the switch and base part I3 and perforated ears I4 and I5. The 40 which also serve as stops for the ends of the bracket A is secured to the base B by a terminal 40 switch arm in its diilferent positions. sleeve I6. The upper end of the sleeve I6 has Still a further object is to provide means for a square head Il while its lower end is rivetedoperating the switch arm including a stationary over a washer I8. At one side of the portion I3 spring for one end to normally urge the switch v of the bracket A, a ange I9 is provided which arm in one direction and a movable pin for the rests against a shoulder 20 of the base B to pre- 45 other and having a spring connection with such vent turning of the bracket A and sleeve I6. A other end. terminal screw 2l is threaded into the lower end Still another object is to provide a means for oi'. th terminal sleeve I6. mounting the switch arm and the leaf springs I provide other terminal sleeves IE and I6b that carry the contacts on a single bracket which having similar washers I8a and I8b and terminal 50 is retained in assembled position by another of screws 2Ia and 2lb. `The sleeves Ilia and IBb are the terminals of the switch. adjacent sockets 22 and 22a formed in the base B With these and other objects in view, my into receive permanent horseshoe magnets 23 and vention consists in the construction, arrange- 23a. The magnets 23 and 23a are retained in the u ment and combination of the various parts of my sockets 22 and 22a by brackets 24 and 24a formed 55 The bracket A is provided with a. pair of lugsy 26 and 26a, which are screw threaded to receive screws 21 and 21a respectively. The screw 21 serves to anchor one end of a leaf spring 28, while the screw 21a similarly serves to anchor one end of a leaf spring 28a. Contacts 29 and 29a are carried by the leaf springs 28 and 28a respectively for coaction with the contacts 25a and 25 respectively. 'I'he springs 28 and 28a are, under tension to normally engage the contacts 29 and 29a with the contacts 25a and 25 and the tension may be varied as desired byv bending the lugs 28 and`28a.

I provide a switch arm 30 having a pair of perforated ears 3| adapted to receive a pivot pin 32. The pivot pin 32 is supported in the pivot ears I4 and I5. Opposite ends of the switch arm 30 are bent downwardly as indicated at 32 and 32a to engage the brackets 24 and 24a, whereas the one bracket serves as a stop for the arm in one of its positions and the other bracket serves as a stop therefor in its other position. The portions 32 and 32a of the switch arm 30 are perforated as at 33 and 33a to receive the ends of the leafl springs 28a and 28 respectively whereby operation of the switch arm may serve to actuate the leaf springs and thereby control the circuits through the contact mechanism of the switch.

For the magnet 23, an armature 34, is provided and for the magnet 23a I provide a similar armature 34a. The armatures are mounted on the switch arm'30 adjacent the ends thereof by screws 35 and 35a. Interposed between the heads of the screws and the switch arm are leaf springs 36 and 36a which are of the shape shown in Figure 9. These springs serve to space the armature from the switch arm as at the right side of Figure 2 when the screw is loosened thus keeping the armature substantially parallel to the switch arm in the different positions of adjustment and thereby always at the proper angle relative to the pole faces of the magnets. The springs 36 and 36a, it will be noted, have upwardly inclined fingers and these are reduced substantially equally in inclination as the screw is tightened. To prevent rotation of the armatures 34 and 34a they are provided with lugs 42 and 42a engaging opposite sides of the switch arm 30.

With the portions 32 and 32a of the switch arm 30 acting as stops, the armatures, however, are prevented from actual contact with the magnets as can be seen in Figure 4, but the differential of operation of either set of contacts of the switch may be varied by loosening the screws 35 or 35a to decrease the differential or tightening them to increase the differential as the magnetic attraction is in inverse squared proportion to the distance of the armature from the magnet when the armature is in stopped position as at the left side of Figures 2 and 4.

One end of the switch arm 30 is provided with a projection 31 with which a spring 38 coacts, the spring being mounted on a projection 39 from the top of the cover C. The tension of the spring 38 is such that it normally tends to separate the contacts 25a and'29 and permit the contacts 25a and 29 to engage.

For operating the switch against the constraint of the spring 38,-1 provide a spring 38a. It is interposed between a projection 31a of the switch arm 30 and an operating pin 40. The pin 40 is slidable in a boss 4| of the cover C and may be engaged by any suitable operating mechanism, 'such as a bellows, bimetaliic element or the like.

'I'he foregoing described switch is very compact in arrangement, yet is capable of carrying relatively heavy currents since snap action is provided by the magnet and-armature arrangement. The compactness of the structure is due to several features of design, among which may be men-I tioned:

l. The bracket A which serves as a pivotal mounting for the switch arm` 30 and has an anchorage means and current conducting means for the switch blades 28 and 28a;

2. The terminal sleeve I8, ||ia and |6b serve to secure the brackets A, 24 land 24a in position and at the same time serve as receptors for the terminal screws 2|, 2|a and 2lb;

3. The brackets 24 and 24a serve both as a means to retain the magnets 23 and 23a in position and as stops for the ends 32 and 32a of the 4. The spring 38 is under tension to normally swing the switch arm 30 in one direction, whereas the normal tendency is for the switch arm to stay at either position due to the effect of the magnets on the armatures, the operating pin 40 then serving through the spring 38a to swing the switch arm to its other position when the pressure against the pin is sufcient tc load the spring 38a until its tension overcomes the tension of the spring 38 plus the pull of the magnet 33 on the armature 34.

When the pin 40 is later permitted to move outwardly in the boss 4|, a point will be reached before the position of Figure 2 is assumed where the tension of the spring 38 will overcome the pull of the magnet 23a on the armature 34a plus the tension of the spring 38a and the switch will return to the position shown in Figure 2.

Some changes may be made in the construction and arrangement of the parts of my device without departing from the real spirit and purpose of my invention, and it is my intention to cover by my claims, any modified forms of structure or use of mechanical equivalents, which may be reasonably included within their scope.

I claim as my invention:

1. In a double throw switch, a base, a switch arm centrally pivoted thereon, an armature carriediby eachend of said switch arm, a magnet for each armature to impart snap action to the switch arm when moved in either direction, a pair of leaf springs between said base and said switch arm, overlapping each other and each at one end extending beyond the other, said leaf springs each having its other end anchored, a contact carried by each of said first ends of said leaf springs, a stationary contact on said base for each leaf spring contact, said leaf spring contacts being normally engaged with said stationary contacts, said switch arm cooperating with said leaf springs to disengage one set of contacts from each other when the switch arm is moved in one direction and to disengage the other set of contacts from each other when the switch arm is moved in the other direction, means biasing said switch arm to one of said positions and an actuator for moving it to the other of said positions.

2. In a double throw switch, a base, a switch arm pivoted intermediate its ends thereon, an armature carried by each end of said switch arm, a magnet for each armature to impart snap action' to the switch arm when moved in either direction, a pair of leaf springs between said base and ,said switch arm and overlapping each other,

said leaf springs each having one of its ends anchored, a contact carried by the other end of I each leaf spring, a stationary contact on said base for each leaf spring contact, said leaf spring contacts being normally engaged with said stationary contacts, said switch arm cooperating with said leaf springs to disengage one set of contacts from each other when the switch arm is movedin one directionand to disengage the other set of contacts from each other when the switch arm ismoved in the other direction and an actuator for effecting movement of said switch arm to its different positions. i

3. In a double throw switch, a base, a bracket thereon having three supports at different distances from said base, a switch arm pivoted to one of said supports, a pair of armatures carried by said switch arm, a magnet for each armature to impart snap action to the switch arm when moved in either direction, a pair of leaf springseach having one of its ends anchored relative to one of the remaining supports with the springs parallel to said base, and a portion of one' spring overlapping a portion of the other, a contact car'- ried by the other end of each of said leaf springs beyond said overlapping portions thereof and as stationary contact for each leaf spring contact, said leaf spring contacts being normally engaged therewith, said switch arm cooperating with said leaf springs to disengage one set of contacts from each other when the switch arm is moved in one direction and to disengage the other set of contacts from each other when the switch arm is moved in the other direction.

4. In a switch structure, a movable switch arm, a pair of oppositely directed leaf springs each having one of its ends anchored, the portions of 40 said leaf springs adjacent Said anchored ends overlapping each other and contacts carried by the other ends of said leaf springs beyond said overlapped anchored ends thereof, a stationary contact for each leaf spring contact, said switch 45 arm cooperating with said leaf springs to effect operation of said contacts with relation to each other when the switch arm is moved in opposite directions, means biasing said arm to one of its opposite positions and an actuator for moving 50 it to the other of its opposite positions.

5. In a switch structure, a base, three terminals thereon, a bracket mounted on said base by the center terminal, a switch arm pivoted intermediate its ends to said bracket, said bracket 55 having a pair of lugs, a pair of leaf springs, each 'having one end anchored to one of said lugs, said leaf springs extending toward and past each other and one of them being located between the other one and the base, contacts carried by said leaf springs, the second and third terminals having stationary contacts normally engaged by said leaf spring contacts, said switch arm having means to pick up one of said leaf springs when the switch arm is rocked in one direction and to pick up the other leaf spring when it is rocked in the other direction and means to impart snap action to said switch arm when moved to either Vof said two positions.

6. In a'.` switch structure, a base, three terminals thereon, a bracket mounted on said base by cooperation of the center one of said terminals therewith, a switch arm pivoted to said bracket, f

a pair of leaf springs, each having one end anchored to said bracket, said leaf springs extending toward and past each other, contacts carried by said leaf springs, the remaining terminals having stationary contacts normally engaged by said leaf spring contacts,-said switch arm having means to pick up one of said leaf springs when the switch arm is rocked in one direction and to pick up the other leaf spring when it vls rocked .in the other direction and means to impart snap action to said switch arm when moved to either of said two positions.

7. In a switch structure, a base,` three substantially aligned terminals thereon, a bracket mounted on Said base by the center one of said terminals, a switch arm pivoted intermediate its ends to said bracket, a pair of reversely arranged leaf springs, each having one end anchored to said bracket with portions of said leaf springs the points of anchorage arranged in overlapping relation, and contacts carried by said leaf springs, the second and third terminals having stationary contacts normally engaged by said leaf spring contacts, said switch arm having means alternately coacting with said leaf springs to separate their contacts from said stationary contacts when the switch arm is rocked in opposite directions.

8. In a switch structure, a base, a bracket mounted on said base and having a pair of lugs, a pair of leaf springs, each having one end anchored to one of said lugs, said leaf springs extending toward and past each other and one of them being located between the other end and said base, contacts carried by said leaf springs, stationary contacts on said base normally engaged by said leaf spring contacts, a switch arm pivoted on said base,v said switch arm having means to pick up one of said leaf springs when the switch arm is rocked in one direction and to pick up the other leaf spring when it is rocked in the other direction and means to impart movement to said switch arm to effect movement thereof to either of said two positions.

9. In a switch structure, a base, three terminals thereon, a bracket mounted on said base by the center terminal, a switch arm pivoted intermediate its ends to said bracket, second and third brackets on the end terminals, a magnet at each end of said base and coacting with the ends of said switch arm to produce snap action thereof when the arm is moved in either direction, said base having sockets receiving said magnets, said brackets retaining said magnets in said sockets resilient means urging said switch arm in one direction and an actuating pin for moving it in the other direction.

10. In a switch structure, a base, a bracket mounted on said base, a switch arm pivoted intermediate its ends to said bracket, second and third brackets on said base, a pair of U-shaped magnets coacting with said switch arm to produce snap action thereof when moved in either direction, said base having sockets adjacent said second and third brackets receiving said magnets at their crosspieces said second and third brackets having iingerlike extensions located between the poles of said magnets and thereby retaining said magnets in said sockets and means for imparting movement to said switch arm.

11. In a switch structure, a base, three terminals thereon, a bracket mounted on said base by said center terminal, a switch arm pivoted to said bracket, second and third brackets on the end terminals, a magnet end coacting with each end of said switch arm to produce snap action thereof when moved in either direction, said last two brackets retaining said magnets assembled on said base, means urging said switch arm to move in one direction and an actuating, element for moving it in the other direction.

12. In a switch structure, a base, magnet sockets therein, a bracket mounted on said base, a switch arm pivoted to said bracket, second and third brackets on said base,'a pair of magnets mounted in said sockets and coasting with said switch arm to produce snap action thereof when the arm is moved in either direction, said second and third brackets retaining said magnets in said sockets, contacts carried by said second and third brackets and cooperating contacts controlled by said switch arm.

13. In a switch structure, a base, three terminals thereon, a bracket mounted on said base by the center terminal, a switch arm pivoted to said bracket, a magnet for each end of said switch arm, an armature on each end of said switch arm, each of said armatures comprising a plate element, a screw for mounting said plate element on the switch arm, lug means to prevent rotation of the armatures relative to the switch arm when the screws are rotated, a spring between each arma'- ture and the switch arm and comprising a relatively iiat central portion and upwardly inclined fingers capable of substantially equal reduction in inclination upon tightening oi said screw and an actuating element for moving said switch arm.

14. In a switch structure, a switch arm pivotally mounted, an armature on said switch arm and comprising a'plate element, a screw for mounting said plate element on the switch arm, means to prevent rotation of the armature relative to the switch arm when the screw is rotated, a leaf spring between said armature and the switch arm and comprising a relatively fiat central portion and upwardly inclined fingers capable of substantially equal reduction in inclination upon tightening of said screw and means for imparting pivotal movement to said switch arm.

15. In a switch structure of the character described, a base, a cover therefor, a switch arm having its central portion pivoted to said base, a spring carried by one end of said cover and engaging said switch arm to normally throw the switch arm in one direction, an actuating pin slidably carried by the other end of said cover, a

spring interposed between said actuating pinand end of thereof,

the other end of said switch arm to swing the switch arm in the opposite direction upon depression of said actuating pin a predetermined distance, permanent magnets associated with each said switch arm to eifect` snap action the tension oi.' said nrst spring being sufficient to swing said switch arm to one position against the action oi' one of 'said magnets and the second spring thereon, and a pair ofA Vcontact mechanims, one for opening a circuit when the switch arm is swung in one direction and the other for opening a circuit when the switch arm is swung in the opposite direction.

16. In a switch structure, a pivotally mounted switch arm, a spring engaging said switch arm to normally swing it in one direction, actuating means, a second spring interposed between said actuating means and said switch arm, said second spring being operative to swing the switch arm in the opposite direction upon movement of said actuating means to a predetermined position, magnets associated with said switch arm to eect snap action thereof, the tension of said ilrst spring being suiiicient to swing said switch arm to one position against the action of one of said magnets and of said second spring thereon, and a pair of contact mechanisms, one for opening a circuit when the switch arm is swung in one direction and the other for opening a circuit when the switch arm is swung in the opposite direction.

17. In a double throw switch, a base, a switch arm pivoted thereon and arranged substantially parallel thereto, means to impart snap action to said switch arm when moved in eitherdirection, a pair of leaf springs between said base and said switch arm and also arranged substantially parallel to said base, said leaf springs overlapping each other and each at one end extending beyond the other, said leaf springs each having its other end anchored, and a contact carried by each of said nrst ends, a stationary contact on said base for each leaf spring contact, said switch arm cooperating with said leaf springs to engage and disengage their contacts with relation to said stationary contacts when the switch arm is moved in either direction and an actuator for said switch arm.

BURTON E. SHAW.

Images