US2523786A

US2523786A - Electrical switch

Info

Publication number: US2523786A
Application number: US771785A
Authority: US
Inventors: Edgar M Soreng
Original assignee: SORENG Manufacturing CORP
Current assignee: SORENG Manufacturing CORP
Priority date: 1947-09-02
Filing date: 1947-09-02
Publication date: 1950-09-26
Anticipated expiration: 1967-09-26

Description

p 6, 1950 E. M. SORENG 2,523,786

ELECTRICAL SWITCH Filed Sept. 2, 1947 Edi/52 M 5 TEN/I77 V f mm Patented Sept. 26, 1950 ELECTRICAL SWITCH Edgar M. Soreng, Skokie, Ill., asslgnor to Soreng Manufacturing Corporation, Chicago, 111., a corporation of Illinois Application September 2, 1947, Serial No. 771,785

4 Claims. 1

This invention relates to electric switches, and more particularly to an improved push button actuated switch of the double throw type.

It is an object of this invention to provide a doublethrow single pole switch actuated by a pair of push buttons by means of which either of two circuit connections may be readily selected for completion by the switch.

Another object of this invention is to provide a compact switch of the character described having a positive snap action and at all times providing positive visual indication to designate which of two circuits the switch is set to close.

Another object of this invention is to provide a switch of the character described which is extremely compact and good looking and is thus particularly suitable for installation in household appliances in which appearance is an important consideration.

Another object of this invention resides in the provision of an inexpensive double throw switch of the character described which has relatively few parts, and, particularly, very few moving parts, and which lends itself especially well to mass production and rapid assembly by unskilled labor.

With the above and other objects in view,

I 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 one com- .plete example of the physical embodiment of the invention constructed according to the best mode so far devised for the practical application of the principles thereof, and in which:

Figure 1 is a perspective view of the switch of this invention with a portion of one wall of the case cut away;

Figure 2 is an end view of the switch;

Figure 3 is a side elevational view of a switch of this invention with one wall cut away to show the switch mechanism, portions thereof being shown cut away; i

Figure 4 is a perspective view of the contactor lever and spring member.

Referring now more particularly to the accompanying drawings, in which like numerals designate like parts throughout the several views, the numeral 5 designates generally the case of the switch of this invention which has a substantially U-shaped cross section, the base of the U forming the front wall 6 of the case and the legs of the U forming a pair of spaced parallel sides 1 thereof. Extensions 8 of the front of the case, having holes 0, form mounting lugs by means of which the switch may be mounted in any conventional manner.

A flat strip of insulative material Ill provides the rear of the case and serves as a terminal head to which the fixed terminals ii, l2 and it of the switch are secured. The terminal head strip is preferably made wide enough so that its marginal side edges M will abut the rear edges it of the side walls of the case, and it may then be secured in position at the rear of the case by means of lugs I6 extending rearwardly' from the side walls, recessed in notches il in the side edges of the terminal head strip and clinched around the rear or outer surface thereof.

Rivets ii, i2 and I3 of suitable conductive material, such as silver or German silver, are accured at equally spaced intervals along the longitudinal centerline of the terminal head strip. Each of these rivets secures a suitable wire connector it to the rear surface of the strip; and the center rivet l2 serves to mount on the inner surface of the strip iii a fulcrum member or standard I9 upon which a contactor lever'35 is pivotally supported at its center for roclring motion about an axis normal to the sides,'-'l of the case, while the heads of the end rivets I If and 13', which lie beneath the opposite ends of the contactor lever, provide the fixed contacts of the switch mechanism per se, andare adapted to be engaged by

contacts

36 and 31, respectively, at the ends of the contactor lever.

Two push buttons 20 and 2|, accessible at the front of the switch case, extend rearwardly into the interior of the case through

apertures

22 and 23, respectively, in its front wall 6. The push buttons are spaced apart longitudinally of the case a short distance so as to lie in line with the opposite ends of the contact lever, and have their axes in a plane parallel to and intermediate the side walls of the case. Preferably they are formed of plastic and have a hollow interior and a rectangular cross section so that they present an attractive appearance. Appropriate indicia may be engraved or otherwise delineated on their front faces 24.

The edges of the

apertures

22 and 23 cooperate with the sides of the outer portions of the buttons to constrain the buttons to fore and aft, or in and out motion. At the rear of each button its sides have ears or enlargements 25 which coact with the inner surfaces of the side walls of the case to limit sidewise play of the rear portion of each button. A rivet-like pintle 26, passing transversely through the inner portion of each of the buttons, has its opposite end portions received in slots 21 in the side walls of the case and these pintles cooperate with the

apertures

22 and 23 in which the outer portions of the buttons are received to preclude tilting motion of the buttons in a plane parallel to the side walls 1. One end of each pintle is swedged, as at 28, to preclude axial displacement of the pintle, and a washer 28 provides a bearing surface between the swedge and the marginal edge surface of the slot.

Thus, it will be seen that the push buttons are constrained to in and out translating motion on axes parallel to one another and to the side walls 1 but normal to the pivot axis of the contactor lever 35. The extent of in and out motion of the buttons is limited by engagement of the pintles 26 with the opposite ends of the slots 2!.

Near the front wall of the case, between the two push buttons, a pivot pin 30 extends from one side wall to the other, parallel to the pintles 26 and the pivot axis of the lever 35, and this pin 30 journals a cross-shaped link member II for oscillating motion in a plane parallel to the sidewalls 1 but midway therebetween. The pivot pin 30 may be formed from a rivet similar to the pintles, and, like them, has its headless end swedged to restrain it against axial displacement.

The link member is preferably formed from insulative sheet material, such as fiber or Bakelite impregnated canvas, and serves to coordinate the motions of the push buttons and to transmit their motion to the switch mechanism per se. Each of the opposite arms 32 and 22 of the link member has a longitudinal slot 55 near its extremity through which one of the pintles 24 passes.

Slots 34 opening to the inner ends of the push buttons receive the extremities of the arms 32 and 3! so that the inner ends of the buttons straddle these arms.

It will thus be seen that the action of the cross shaped link is such that when one of the push buttons is moved inwardly the link rocks about the pivot pin 30 to propel the other push button outwardly of the switch case.

Opposite the axis of the pivot pin III, the link member carries a roller 38 which is at all times in engagement with a bowe'd leaf spring ll on the inner side'of the contactor lever. The roller minimizes friction between the actuator and the spring strip and comprises a pair of washers 40 journaled on a small rivet 4! at the base of the actuator, on either surface of it, to provide a pair of small spaced apart rollers which ride upon the spring strip during motion of the actuator therealong as the actuator rocks about the pivot pin. The roller 38 is so located on the actuator as to be carried slight distances to either side of the line passing through the pivot pin 30 and the pivot axis of the contactor lever 25 upon rocking motion of the actuator.

The fulcrum member is is a substantially U- shaped metal stamping having a notch 42 in each of its upper edges in which trunnion lugs 43 on, the contactor lever 25 are received to mount the contactor lever for rocking motion about the fulcrum. The rivet l2 passes through aligned holes in the base of the fulcrum member, the terminal head strip Ill, and a wire connector it to mount the fulcrum member and the wire connector on opposite faces of the strip and to conduct current from the connector to the fulcrum.

The contactor lever is stamped from conductive material, such as spring brass or phosphor bronze, in the form of a strip having lugs 43 extending laterally from the middle of each of its side edges. These lugs have an arcuate cross section in the direction of the length of the contactor lever and are adapted to be received in the notches 42 in the fulcrum member and thus serve as trunnions upon which the contactor lever rocks.

The

contacts

26 and 21 are preferably formed of silver or German silver rivets secured through holes at the ends of the lever. It will be seen that the contactor-lever serves as a connector which completes a circuit between the wire connector secured to the fulcrum member and that secured to contact II or contact l2, depending upon which end of the contactor is rocked into engagement with a terminal head contact.

The bowed leaf spring 29 isformed from a strip of light, springy material somewhat longer than the contactor lever, and serves to impose yielding bias between the actuator and the contactor lever. One end 44 of the leaf spring is secured fiatwise to an end of the contactor lever by means of the contact rivet 26, while its other end 45 engages the opposite end of the contactor fiatwlse. The medial portion 46 of the spring is bowed to be spaced from the front face of the lever at the medial portion thereof. A slight hump 49 in the medial portion of the spring,

substantially in line with the trunnion axis of the lever, provides a definite detent action and affords positive snap switch action.

To prevent the spring strip from rotating about the rivet It with respect to the contactor, a tang 41 at the riveted end 44 of the spring strip engages in a notch-4| in the corresponding end of the contactor strip. If desired, a second leaf spring 29' may be employed, identical in every respect with the first, to afford greater bias pressure and consequently more positive switch action. The bowed shape of the leaf spring makes for positive engagement of the switch contacts, since the outer ends of the contactor lever are urged rearwardly by the ends of the leaf spring; hence a relatively light strip of metal may be employed for the contactor lever.

It will be seen that in operating the switch of this invention one of the push buttons is depressed (i. e., moved rearwardly or inwardly) depending upon the circuit which it is desired to complete. Assume, for example, that the button 20 is pushed. The corresponding arm 33 of the link member is moved rearwardly toward the terminal head I! and the other arm 33' is rocked forwardly toward the front wall 5 of the case as the link member pivots about the pin 30, thus bringing the other push butfion 2| to the forward or out position. At the same time, the actuator roller 38 of the link member is moved along the spring member 39 from the left side (Fig. 3) of the rocking axis of the contact lever to the right side thereof, over and across the hump 49 on the spring. As the roller 38 passes the line joining the pivot axes of the link member and the contact, representing dead center of a toggle, the contactor lever will be rapidly swung in a clockwise direction to engage its contact I! with the stationary contact [3 with a snap action.

A circuit will thus be completed from the wire connector secured to rivet I 2' through the fulcrum member, the contactor lever and the contact 31 to terminal i3, thus connecting contact II in series circuit with contact 13. visual indication of this circuit connection is provided at all times by the fact that push button is depressed while push button 2| is extended. This condition is depicted in Fig. 3. It will be seen that contact 31 is urged into pofltive engagement with rivet N by the free end of the leaf spring 33.

To obtain the other circuit of the switch the push button 2! is depressed, and the link member arms 33 and 33', rocking about the axis of the pin in a clockwise direction as viewed in Fig. 3, swing the actuator back across the hump of the spring member to the other side of the fulcrum axis, disengaging the contacts 31 and I3 and engaging contacts 36 and II with a snap action as the lever is rocked counterclockwise to its other position.

The second of the two possible switch connections available by means of the switch of this invention is thus completed, connecting contact l2 in series circuit with contact H; and this connection is indicated visually by the fact that push button 21 is depressed while push button 20 is extended.

It will be readily understood that the length and location of the slots 21 in the side walls of the case not only determines the travel range of the push buttons but also defines the limits of arcuate motion of the actuator.

It will be noted that assembly of the switch of this invention is. extremely simple. The two push buttons are inserted from the the rear of the case through the

apertures

22 and 23 in the front wall of the case, and the link member, with the washers riveted in place thereon, is set in place in the slots 34 in the push buttons. The

pivot pin 30 is then passed through the holes in the side walls of the case and the head of the link member, and its headless end is thereupon swedged. Similarly the pintles 26 are passed through the slots 21 in the side walls of the case, through holes in the rear or inner portion of the push buttons, and. through the slots 55 in the arms 33 and 33' of the link member, and washers 29 are slipped on their ends which are then swedged.

The terminal head is assembled by inserting rivets ii and i3 through the end holes in the insulative strip and through the wire connectors andjnserting rivet 12' through the base of the fulcrum member, the strip, and a wire connector, and then peening the ends of the three rivets. Rivet contact 31 is secured to the contactor lever and the spring member is secured in place on the lever by means of rivet 36. The lever is then set in place on the fulcrum and the entire terminal head assembly is placed in position at the rear of the case. Clinching the lugs [6 around the rear of the terminal head strip completes the assembly of' the switch.

From the foregoing description, taken together with the accompanying drawings, it will be readily understood that this invention provides a double throw switch of the character described which will be unusually simple, compact and neat in appearance, and which will provide positive snap action and instant visual indication of the circuit which the switch is completing.

What I claim as my invention is:

1. In a switch of the character described: a unitary substantially U-shaped case, the legs of Positive the U providing a pair of side walls and the base of the U providing a relatively flat front wall at right angles to the side walls; a pair of push buttons accessible at the front of the case and extending rearwardly into the interior of the case through apertures in said front wall thereof, said push buttons having a substantially rectangular cross section and the apertures in the front wall of the case having a corresponding shape so as to preclude rotation of the buttons in the apertures while guiding the same for movement axially into and out of the case; a pintle carried by each push button at its end inside the case, the opposite ends of each pintle projecting through aligning slots in the side walls of the case extending in a direction normal to the plane of said front wall whereby said pintles cooperate with the apertures in said front wall to constrain the buttons to substantially in and out translating motion; an actuating lever pivotally carried by the side walls of the case for rocking motion on an axis substantially parallel to the front wall of the case and lying between said push buttons; and means for connecting said lever with the buttons comprising oppositely extending arms on the lever each projecting into a slot in the inner end of the adjacent push button, said arms having slots in their inner ends to receive the pintles whereby inward motion of one .push button rocks the actuating lever on its axis and effects outward motion of the other push button.

2. In a switch of the character described: a unitary substantially U'-shaped case, the legs of the U providing a pair of side walls parallel and relatively close to one another, and the base of the U providing a relatively flat front wall for the case; an actuating lever pivotally carried by said side walls of the case for rocking motion inside the case about an axis intermediate the ends of said side walls and near the front wall of the case, said lever having opposite amns extending toward the ends of the case, and each of said arms having a slot in its outer end portion extending lengthwise of the arm; a pair of push buttons accessible at the front of the case and extending rearwardly into the interior of the case through apertures in the front wall thereof, one at each side of said axis of rocking motlon of the actuating lever, so that the inner end of each button extends toward the slotted extremity of one of the arms of the actuating lever, said push buttons having slots in their inner extremities in which the slotted ends of the arms of the actuating lever are received; and a pintle extending through the inner end of each push button and through the slot in the adjacent lever arm to pivotally connect each push button with the lever, said pintles extending through aligned slots in the side walls of the case extending in a direction normal to the front wall of the case whereby the pintles and the apertures which receive the push buttons cooperate to constrain the push buttons to substantially straight in and out motion.

3. In a switch of the character described: a case including a front wall and a pair of opposite side walls substantially perpendicular to the front wall and parallel to one another; an actuating lever pivotally carried by the case for rocking. motion inside the case about an axis interme-- diate the ends of said side walls and perpendicular to them, said lever having opposite arms extending toward the ends of the case; a pair of push buttons accessible at the front of the case and extending rearwardly into the interior of the case through closely fitting apertures in the front wall thereof whereby the outer portions of the buttons are guided for axial in and out motion, said buttons also having slots in their inner portions, parallel to the side walls of the case, in which the lever arms are received to hold the lever centered between the side walls: a connection between each push button and one of the arms on the lever whereby axial inward motion of a push button is translated into rocking motion of the lever about its axis; and cooperating means carried by the inner portions of said push buttons and the side walls of the case for guidingly constraining the inner portions of---the push buttons to axial motion, said means including shoulders on each side of each push button slidable along portions of said side walls.

4. In a switch ofv the character described: a case including a front wall and a pair of opposite side walls substantially perpendicular to the front wall and parallel to one another; an actuating lever carried by the case for rocking motion inside the case about .an axis intermediate the ends of said side walls and perpendicular to them, said lever having at least one arm extending from its axis toward an end of the case; a push button accessible at the front of the case and extending rearwardly into the interior of the case through a, closely fitting aperture in the 8 front wall thereof whereby the outer portion of the button is guided for axial in and out motion; cooperating means at the inner end of the button and on the side walls for constraining the inner portion of the button to axial in and out motion. said last named means cooperating with the aperture in the front wall of the case to constrain the entire button to such motion; a motion transmitting connection between the button and the lever arm whereby axial motion of the button is translated into rocking motion of the lever about its axis: and cooperating tongue and slot means on the inner .portion of the button and on the arm of the lever for constraining the lever arm to motion in a plane parallel to the side walls of the case and precluding other types of motion.

EDGAR M. BORING.

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

UNITED STATES PATENTS