US2838622A

US2838622A - Electric switch

Info

Publication number: US2838622A
Application number: US523521A
Authority: US
Inventors: Robert W Bachi
Original assignee: Controls Company of America
Current assignee: Controls Company of America
Priority date: 1955-07-21
Filing date: 1955-07-21
Publication date: 1958-06-10
Anticipated expiration: 1975-06-10

Description

R. w. BACH! ELECTRIC SWITCH Filed July 21, 1955 June 1o, 195s nited States Patent Office ELECTRIC SWITCH Robert W. Rachi, Marion, ind., assigner, by mestre assignments, to Controls Company of America, Schler Park, Ill., a corporation of Delaware Application July 21, 1955, Serial No. 523,521 9 Claims. (Cl. 200m@ This invention relates to electric switches and has more particular reference to improvements in single pole double throw electric switches.

It is the purpose of this invention to provide a single pole double throwvelectric switch of simplified construction featuring a heating contactor normally occupying a switch off position seated upon a pair of spaced supports which provide alternate fulcrums about which the contactor may be tilted to carry contact means thereon in opposite directions toward and from engagement with a pair of stationary contacts.

More specifically, this invention has as its purpose the provision of an electric switch of the character described, wherein the alternate fulcrums upon which the contactor is floatingly supported are carried by a pair of plunger like actuators which when alternately moved out of a normal switch off position, eifect tilting of the contact portion of the contactor in opposite directions toward and from engagement with its cooperating stationary contact.

Still another purpose of this invention resides in the provision of an electric switch of the character described wherein a single spring acting upon the floating contactor at a point intermediate its alternate fulcrums yieldingly maintains the contactor seated on the fulcrums and also serves as biasing means for both actuators to yieldingly urge the actuators in the same direction.

With the above and other objects in view, which will appear as the description proceeds, this invention resides in the novel construction, combination and arrangement of parts substantially as hereinafter described and more particularly defined by the appended claims, it being understood that such changes in the precise embodiment of the hereindisclosed invention may be made as come within the scope of the claims.

The accompanying drawing illustrates two complete examples of the physical embodiments of the invention constructed according to the best modes so far devised for the practical application of the principles thereof, and in which;

Figure l is an elevational view of a single pole double throw switch embodying the principles of this invention, portions thereof being broken away and shown in section;

Figure 2 is a View similar to Figure 1 but showing the contactor of the switch tilted out of neutral position to one circuit closing position;

Figure 3 is a view similar to Figure 2 but showing the contactor of the switch tilted to its other circuit closing position; and

Figure 4 is a View similar to fied embodiment of the inventio Referring now more particularly to the accompanying drawing in which like numerals designate like parts, the numeral S generally designates a supporting structure or housing for the switch having a base 6, a top wall 7 spaced a distance above the base, and

upright end walls

8 and 9 extending between and joined to the base and the top wall.

Figure l showing a modi- 2,838,622 Patented June l0, 1958 The switch mechanism 10 of this invention is mounted in the housing and comprises an elongated contactor blade 11, a pair of vertically spaced stationary contacts 12 and 13 Xed on the end wall 9 of the housing, and a pair of

actuators

14 and 15 movably carried by the base 6. The actuators have plunger-like lower end portions 16 which are slidingly received in spaced vertical holes 17 in the base opening to its upper surface, and are further provided with enlargements 13 thereon spaced from their upper ends and positioned above the base 6.

The upper surfaces of the enlargements 18 are rounded and provide fulcrums upon which the contactor 11 seats. For this purpose, the contacto-r is provided with holes 20 to loosely receive the pil0t-like upper end portions 21 of the actuators which project upwardly from the enlargements 18, and the pilotlike upper end portions of the actuators thus hold the contactor against edgewise displacement from the fulcrums provided by the enlargements 18 without interfering with alternate tilting motion of the contactor about its fulcrums.

ln the embodiment of the invention illustrated in Figures l to 3, the switch is provided with an operating member 23 comprising a rod which is axially slidably received in a bore 24 in the base crosswise intersecting the holes 17 in which the lower plunger-like ends of the actuators slide. Normally the rounded lower ends of the actuators engage the periphery of the rod 23 as shown in Figure l, to be held thereby in predetermined positions on the base with their enlargements 18 spaced equal distances from the upper surface of the base.

A coiled compression spring 26 exerts a downward force upon the contactor to yieldingly hold it engaged with both of its fulcrums, and this spring, acting through the contactor, also presses the actuators downwardly to assure engagement of their lower ends with the periphery of the rod 23. The spring 26 is properly held in place exerting its force upon the contactor at a location intermediate its fulcrums by a pilot 27 projecting downwardly into the coils of the spring from the top wall 7 of the supporting structure, and by a boss 28 on the upper face of the contactor blade 11 intermediate the enlargements 18 upon which the contactor rests.

In the normal positions of the actuators described, therefore, the enlargements 18 on the actuators hold the contactor 11 in a neutral position extending lengthwise over the base substantially parallel thereto but spaced therefrom, and with the outer end portion 30 of the contactor remote from its fulcrums substantially midway between the upper and lower stationary contacts 12 and 13 respectively.

The contactor 11 is tilted about one or the other of its fulcrums toward engagement with one or the other of the stationary contacts as a consequence of motion of one of the actuators out of its normal position defined by the engagement of its lower end with the periphery of the operating rod 23. For this purpose, the operating rod is provided with a circumferential groove 32 therein which may normally occupy a position substantially midway between the two actuators in the neutral or switch off position shown in Figure l.

When the operating rod is shifted to the left to the position shown in Figure 2, its circumferential groove 32 aligns with the plunger-like lower end portion of the actuator 14, and the actuator 14 is propelled downwardly under the force of the compression spring 26 into the groove 32 while the actuator 15 remains in its normal position. As a consequence, the spring 26, which acts upon the contactor at an area intermediate its two fulcrums, causes the contactor to tilt upon the fulcrum of the actuator 15' in a counterclockwise direction to carry contact means on its outer end portion 30 upwardly into engagement with the upper stationary contact12 as shown in Figure 2. It will be understood that the outer end portion of the contact blade may itself provide the contact means o`n the contacter although it is the usual practice to secure a contact point 34 to the blade forthis purpose.

While the contacter l1 may be made of relatively stiff metal, it is shown as a thin, ilexible blade. Consequently, the engagement of its contact means 34 with the upper stationary contact 12 will cause the blade to flex and assume an upwardly bowed attitude (as shown in Figure 2) as a consequence of the spring force exerted on the contacter at the side of its fulcrum remote from the stationary contact l2.

When the operating rod 23 is shifted to the right from its neutral position seen in Figure l to bring its-circumferential groove 32 into alignment with the actuator 15, the latter is propelled downwardly into the groove of the operating red by spring 26 while the other actuator 14 remains in its normal position, and the contacter 11 is Ithus caused to tilt in a clockwise direction to carry the contact'means on its outer end portion downwardly into engagement with the lower stationary contact 13 as seen in Figure 3. In this case, the contacter blade will assume a downwardly bowed attitude by reason of the fact that it is supported at its opposite end portions while the spring force is being applied to a middle portion thereof.

VIt will be understood, of course, that the stationary contacts 12 and 13 are so spaced that as the contacter .is tilted te either circuit closin7 position, its contact means 34 will be engaged with one or the other of the stationary contacts before the depressed actuator bottoms in the groove 32 of the operating rod 23. Y

It will also be apparent that while the operating rod has been shown provided with but a single circumferential groove 32, there may be instances when it is desirable to provide the rod with more than one groove to enable selective depression of the actuators7 or even simultaneous depression of the actuators, in which latter event the contact means 34 is brought into engagement with the lower stationary contact 13.

Terminals 35 Vconnected with the stationary contacts 12 and 13 may be provided on the end wall 9 of the switch housing, and iioating contacter il may be connected by a flexible pigtail 36 with a third terminal 37.

the fulcrums on the actuators so that the lead does not have toy be excessively long to compensate for the tilting motion of thercontactor.

In'the embodiment ofthe invention shown in Figure 4, the enlargements i8 on the actuators provide downwardly facing shoulders 39 on their undersides which are yieldingly held engaged with the upper surface of the base 6 by the spring 26 te deine the normal positions of the actuators, and the neutral position of the contacter. In this case also, the lower plunger-like end portions 16 of the actuators project all the way through the base to have portions exposed atrits underside to provide for manual depression of the actuators upwardly into the housing. No operating member such as therod 23 previously described is necessary.

Thus when the actuators are alternately depressed in upward directions out of their normal positions, the contacter is caused to tilt in opposite directions upon the fulcrums provided by the rounded upper surfaces of the'enlargements 13 Von the actuators in a manner' similar to that described previously. i

From the foregoing description, taken together with the accompanying drawings, it will be readily apparent tothose skilled in the art that this invention provides an exceptionally simple single pole double throw electric switchV by reason of the novel manner in which the 4 contacter of the switch is iloatingly supported on alternate fulcrums which effect tilting of the contacter in opposite directions when the fulcrums are alternately shifted eut of normal positions.

lfd/hat I claim as my invention is:

l. In an electric switch: a base; a contacter overlying the base in spaced relation thereto and having contact means at ene portion thereof; a pair of actuators extending between the base and the contacter; means j mounting said actuators in spaced, side by side relationship on the base and for motion to and from dened positions along paths which intersect the contacter; means on said actuators loosely engaged with portions of the contacter which are spaced in the same direction from said contact means to provide alternate fulcrums at one side of the contacter and engaged thereby, about either of which fulcrums the contacter may tilt; and spring means acting on said contacter in a direction to maintain the contacter seated'upon both fulcrums; motion of one of said actuators away from its detined position effecting tilting of the contacter about one of said fulcrums to carrythe Contact means on the contacter in one direction, and motion of the other of said actuators away from its defined position effecting tilting of the contacter about the other of said fulcrums to carry the contact means on the contacter in the opposite direction.

2. ln an electric switch having a contacter, means mounting the contacter for back and forth tilting motion se as te carry contact means on the contacter in opposite directions, comprising: a base having spaced Vsubstantially parallel holes therein; a pair of plunger-like actuators each having one'endportion slidably received in one of said holes; cooperating means on the base and said actuators defining the normal position of eachV of said actuators, out of which normal positions the actuators are movable independently on one another; means providing a fulcrum on each actuator spaced from butfaciug the other end thereof; said contacter seating upon said fulcrums and having holes therein to loosely receive the other end portions of the vactuators which project from said fulcrums; and spring means acting upon the contacter in a direction to hold the contacter seated on beth of said fulcrums; motion of one of said actuators away from its normal position effecting tilting of the contacter about one of said fulcrums to carry the contact means on the contacter in one direction, and motion of the other of said actuators away from its normal position efecting tilting of the contacter about the other of said fulcrums to carry the contact means on the contacter in the opposite direction.

3. In an electric switch: a supporting structure having a base; spaced stationaryV contacts on the supporting structure; a contacter overlying the base and having contact means on one portion thereof cooperable with said stationary contacts; a pair of actuators extending between the base and another portion of the contacter; means mounting said actuators on the base for back and forth motion along spaced paths which intersect the contacter; cooperating means on the actuators and the base'dening the normal positions of the actuators; means on the actuators providing alternate fulcrums engaged with one side of the contacter and about either of which fulcrums the contacter may tilt; and spring means acting on said contacter in a direction to maintain the contacter seated upon both fulcrums so that the contacter is normally held thereby with its contact means between and spaced from said stationary contacts Awhen both actuators are in their normal positions; motion of one of said actuators away from its normal position effecting tilting of the contacter about one of said fulcrums to carry said contact means in one direction into engagement with one of the stationary contacts, and motion of the other of said of the contacter about the other of said fulcrums to carry said Contact means in the opposite direction into engagement with the other stationary Contact.

4. The electric switch set forth in claim 3 further characterized by the provision of cooperating loosely engaging means on the contactor and said actuators for holding the contactor y.against displacement from said tulcrums without interfering with tilting of the contactor thereon.

5. In an electric switch: a supporting structure having spaced stationary contacts mounted thereon and having a base provided with a pair of holes on spaced upright axes; a plunger axially slidably received in each of said holes and projecting upwardly from the base; cooperating means on the base and said plungers dening the normal axial positions of said plungers in their holes, out of which normal positions the plungers are movable axially and independently `of one another; an enlargement on each plunger spaced from the upper end thereof but lying above said base, said enlargements providing spaced fulcrums having rounded upper surfaces; an elongated contactor having one portion seated upon said fulcrums and having holes therein through which the upper end portions of the plungers loosely project to hold the contactor against displacement from the fulcrums in directions normal to the plunger axes, without interfering with tilting motion of the contactor about either fulcrum, said contactor having contact means t another portion thereof remote from said first designated portion of the contactor which contact means is cooperable with said stationary contacts; and a spring carried by the supporting structure and acting upon a portion of the contactor intermediate said fulcrums and in a direction to hold the contactor engaged therewith so as to prevent accidental displacement of the contactor off of the upper end portions of the plungers in the direction of the plunger axes; motion of `one of said plungers away from its normal position effecting tilting of the contactor about one of said fulcrums to carry said contact means in one direction toward engagement with one of the stationary contacts, and motion of the other of said plungers away from its normal position effecting tilting of the contactor about the other of said fulcrums to carry said contact means in the opposite direction toward engagement with the other stationary contact.

6, The electric switch set forth in claim 5 further characterized by the provision of movable operating means connected with said plungers for effecting motion thereof out of their normal positions.

7. The electric switch set forth in claim 6 wherein said operating means comprises a bar carried by the base beneath the plungers and against which their lower ends bear to define the normal position of the plungers, said bar being constrained to back and forth sliding motion along a path crosswise of both plungers and being notched to provide for movement of the plungers out of their normal positions by said spring as a consequence of sliding of the bar back and forth to positions at which the lower ends of the plungers align with the notched portion of the bar.

8. The electric switch set forth in claim 5 wherein the lower end portions of the plungers project through the base and are exposed at the exterior of the supporting structure to provide for manual actuation of the plungers lout of their normal positions.

9. The switch set forth in claim 8 further characterized by the fact that said enlargements on the plungers define downwardly facing shoulders at their undersides which are yieldingly held engaged with the base by said spring to define the normal positions of the plungers.

References Cited in the tile of this patent UNITED STATES PATENTS 292,687 Scott Jan. 29, 1884 1,551,379 Eaton Aug. 25, 1925 1,628,191 Rattay May 10, 1927 FOREIGN PATENTS 431,753 Germany July 16, 1926 UNITED STATES PATENT OFFICE CERTIFICATE OE CORRECTION Patent Noo 2,838,622 June lO 1958 Robert W Baohi It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 4, line 36, for "on oneH read of onev fm; column 5f, line 269 for means t" read er means .at

Signed and sealed this 12th day of August l958f.

(SEAL) Attest:

KARL H, AXLINE ROBERT C. WATSON Commissioner of Patents Attesting Ocer Patent NQ, 2, 838,622

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION June l0, 1.958

Robert W Baoh VIt. is hereby certified that error appears in the printed specification of 'bhe above numbered patent requiring correction and that the Said Letters Pa'bent should read as corrected below.

Coltmm 4 line 36, for "on onen read 'of oneA um; column 5 line 2,6, for "means t" read at en,

Signed and sealed this 12th day of August 1958:.

(SEAL) Attest: v

KARL 11 Amm Attesting Ofcer ROBERT C. WATSON Commissioner of Patents