US2634340A

US2634340A - Push-button switch

Info

Publication number: US2634340A
Application number: US160667A
Authority: US
Inventors: Hugh W Batcheller
Original assignee: Individual
Current assignee: Individual
Priority date: 1950-05-08
Filing date: 1950-05-08
Publication date: 1953-04-07
Anticipated expiration: 1970-04-07

Description

April 7, 1953 H.1w. BATCHELLER 2,634,340

PUSH-BUTTON SWITCH Filed May 8, 1950 3 Sheets-Sheet 2 y /NI/ENTOR HUGH W. BATCHELLER ATTVS April 7, 1953 H. w. BATCHELLER 2,634,340

PUSH-BUTTON SWITCH Filed May 8, 1950 5 Sheets-Sheet 5 /N VEN TOR HUGH W BA TCHEL LER Patented Apr. 7, 1953 UNITED STATES PATENT OFFICE 4 Claims.

rIhis invention relates to a push-button switch of a type which is sometimes used on electric ranges or similar apparatus having a plurality of circuits to be connected in diierent combinations. lt is an object of the invention to provide a pushbutton switch which operates easily and positively, which is composed of relatively simple and easily manufactured parts, which can be readily assembled, and which is reliable and durable in operation.

In the embodiment of the invention herein shown and described, a set of eight push-buttons is included in a switch designed for use with a range unit consisting of two elements adapted to be connected to a three-wire power circuit in various ways to give seven degrees of heating according to which of seven of the buttons is pressed, the eighth button being a release button to restore to the off position any button which has been pushed in to close a circuit through one or both of the heating elements in the unit.

For a more complete understanding of the invention reference may be had to the following description thereof and to the drawing, of which- 'Figure 1 is a front elevational View of a pushbutton switch embodying the invention;

Figure 2 is a rear elevation of the same;

Figure 3 is an exploded perspective view of the switch, portions being broken away to show in section;

Figure e is a section on the line 4-4 of Figure 1;

Figure 5 is a section on the line 5 5 of Figure 4';

Figure 6 is a perspective View of the rear portion of the switch, the cover being shown as removed;

Figure 7 is a fragmentary exploded view of one of the fixed terminals and bridging conductors;

Figure 8 is a diagrammatic view of the slides in one position of operation and the corresponding circuits; and

-Figure 9 is a diagrammatic view of the slides in another position of operation and the corresponding circuits.

The switch may include a molded casing member 2t which is elongated and is shown in the drawings and hereinafter described as in a vertical or erect position. This casing, which may be molded in one piece if desired, has a front portion 22 and a rear portion 24, the former being longer, narrower and deeper than the latter. These two portions have a common partition wall 2B which donnes front and rear chambers 2S and 3B. A front cover 32 closes the chamber 28, a rear cover 34 closing the rear chamber 30. The casing member 2Q is of moldable insulating material, the front cover 32 being of sheet metal or any other suitable material. The rear cover 34 is preferably a plate of insulating material. The switch elements themselves are enclosed in the rear chamber 3c. The front chamber 23 encloses the actuating means by which the movable switch elements are operated. For this purpose, a plurality of slides du, 12, d4, and 46 are mounted side by side in a central channel in the front chamber 2a and are adapted to slide vertically a limited distance therein. The extent of sliding movement of each of these slides is positively limited by

lugs

50, 52, 54, and 56 respectively. rihese lugs project through slots in the partition wall 26. Thus the lug 5B projects through a slot 5S. The lug 52 projects through a slot E0. The lugs 5d and 55 project through a slot 62. Each of these slots is of limited length so that the portion of each lug which rides in a slot engages one end or the other of the slot when the corresponding slide reaches its limits of movement. Each lug has a longer portion immediately adjacent to the slide and a shorter portion projecting into the rear chamber 3B to engage switch elements as hereinafter described. In the forward edge of each slide is a series of V-notches 64 adapted to be entered by corresponding buttons which have wedge ends for this purpose. In the switch illustrated on the drawings, eight such buttons are provided as at l), 12, '14, '16, 18, 8G, 82, and 32%. As these buttons are preferably of identical shape and construction, the description of one will serve for all. The button 84 shown in Figure 3 is preferably a molded plastic member which is somewhat elongated and may have a rectangular cross section slidably fitted through one of the rectangular apertures 86 in the front cover plate 32. The button 84 may be slightly dished as at 88 at its forward end to receive a finger tip of the operator when the button is to be pushed in for operation of the switch. Each button has at its rear end a central wedge 90 which is adapted to enter and t in corresponding V- notches (i4 in the several slides. On either side of the wedge ed at the rear end of the button is a semi-cylindrical projection 92 having a bore 34 extending therein to receive the end of a compression spring 96. There are thus two springs -96 provided for each button, these springs being normally compressed so as to press the button forward. The semi-cylindrical projections S2 of each button extend beyond the side walls of the rectangular portion and thus serve as stops to limit the forward o1' outward movement of the button. On two opposite side faces of the rectangular portion of each button are a pair of locking lugs 98, the purpose of which is to retain any of the seven active buttons in its rearward position until the locking means is released, the uppermost button 8E being simply for releasing any of the other buttons which may be pushed in to its rearward position. Each lug 98 has an inclined cam face Idil at its rear end and a front face H32 on which a latch element can catch. Cooperating with these locking lugs is a locking plate iili, this plate having a series of openings i large enough to receive a button and its lugs 98. The locking plate |56 may conveniently be made of sheet metal which can be punched and stamped to shape. A portion of the metal which is cut away to form the apertures it is preferably rolled into a cylinder |08, one such cylinder being between each pair of successive apertures |86. These cylinders are the latch elements which engage lugs 98 on the pushbuttons. When a button is pushed in, the cam face me of its upper lug 98 engages the corresponding latch element H38 and cams the locking plate Hit upward. The weight of the locking plate itil tends to move it down so that when a button is pushed further in and the latch element |58 moves beyond the lug 98, the plate then drops so that the latch element its catches on the lug 98 and maintains the button in its rearward position. in Figure 4 the button 82 occupies such position, its upper lug 98 being caught behind a cylinder m8 of the locking plate ltd. In order to insure the proper operation of the locking plate Ill when the switch is mounted in any desired position, a suitable leaf spring |23 is mounted in the upper end of the front chamber Eil so as to bear resiliently against the upper end of the locking plate it. 1t may be observed that whenever any one of the buttons is pushed in, the locking plate Illiis lifted so that if another button is in its in position, it is thereupon released and is pushed forward to its out position by its springs 96. The only function of the uppermost button Sii is thus to release any of the other buttons which may be locked in its in position. The notches 6ft in the several slides are approximately inline with the wedge ends of corresponding buttons but are for the most part slightly offset up or down so that when any one of the seven active buttons is pressed inward, its wedge end Se cams one or more of the slides so as to move such slides longitudinally and thus to operate one or more of the movable switch elements in the rear chamber 35. The notches Bil are so arranged that when any one of the seven active buttons is pushed all of the way in so as to line up the corresponding notches in the four slides,

' then at least one of thel notches opposite each of the other six active buttons is out of alignment with the wedge end of its corresponding button. Hence not more than one button can be pushed all the way in at the same time.

The four lugs which project through the partition wall 26 into the rear chamber 32| move up and down with their respective slides and press against corresponding resilient elements which, as shown on the drawings, are bridging conductors carrying contact points. As indicated in Figure 2, four such resilient bridging conductors M2, Mii, H6, and H8 are mounted in the rear chamber Sii. These bridging conductors are secured at one end to respective terminal members |26, |22, mit, and |26, so that the free end of each conductor swings in a plane parallel to the direction of movement of the slides. A typical bridging conductor and its terminal member are illustrated in Figure 1. As therein shown, conductor H2 consists of a strip of spring metal such as bronze which is bent to an L shape except that the bend is curved. The short leg of the L is permanently secured to the terminal member |26 by any suitable means such as extruded eyelets 33 which pass through holes |32 in the conductor and are clinched. The terminal member |25 is preferably made oi heavy strip metal, a portion of which is a blade projecting through the rear cover plate 3Q as indicated in Figure a. The other end of the member E25 nts into a suitable recess it@ in the partition wall 25. The short leg of the L-shaped conductor H2 is thus rmly xed. The free end portion 52.*5 of the conductor is provided with a Contact point or element |35 which is clinched in a hole in the end portion |36 and moves therewith when the long leg of the l.. is pushed back and forth, the motion of the movable contact element E3B being in a direction substantially parallel to the sliding movement of the four slides. As shown in Figures 2, 8, and 9, the conductors H2 and M are provided with single contact elements 33 and ill@ but the conductors |15 and HS are provided with double contact elements Hifi and it respectively. All of these elements move in paths which, while slightly arcuate, are substantially parallel tc the direction of movement of the slides. Fixed contact elements |125, idd, iii, |52, B55, and i525 are mounted within the chamber il in positions to be engaged by corresponding movable contact elements. For the operation of the bridging conductor H2, the lug 5S bears against it at an intermediate point between the bend and the free end which carries the contact element |38. in like manner the conductor lid is engaged by an edge of the lug 55, the conductor iid is engaged by the lug 5t, and the conductor H8 is engaged by the lug 52. The lugs are pressed toward the respective bridging conductors by springs which are in the rear chamber, these springs being preferably in the shape of hairpins. Thus a spring i60 is mounted against the partition wall 26 with the bend of the spring engaging on a short pin |62 which is integral with and projects from the wall 25. The legs of the spring it@ diverge when unstressed but are sprung together to engage the lugs 5t and 5L! respectively so as to press the lug 56 against the conductor H2 and to press the lug 5d against the conductor Hdl. In like manner a spring |64 is mounted against the partition wall 25, one of the lugs of this spring being arranged to press against the lug 5@ so as to press this lug against the conductor l5. The legs of the spring |56 diverge at a considerable angle when the spring is unstressed. rihcse legs are held in approximately parallel position by a stop member |55 which may be integral with the partition wall 25 and has a C shape, the arms of which corinne the legs of the spring |54 in a state of tension so that when the lug 5B is moved downward by its slide, it is resisted by a considerable initial tension or" the spring |64. When the slide is released, the spring |64, being stronger than the resilient conductor H5, moves the lug 5u and its slide upward until the spring is stopped by the stop member |55. At this point the double contact element H52 is in a neutral position between the xed elements |59 and |52. The slide carrying the lug 5G is movable by certain of the push-buttons to an active position in which it causes the contact element M2 to bear against the fixed element |52, as vshown in Figure 9. Otherpush-buttons move the lug inthe other direction against the pressure of thespring permitting the conductor itt, which is under tension, to press the contact element U12 against the xed point tbe.

ln like manner a hairpin-shaped spring llt is mounted against the partition wall 2t, the legs ,oi this spring being coniined under` tension by a stop member' |72 which may be similar to the stop member 5&5. Aleg of the spring im bears against the lug 52 when the parts are in the positions shown in Figure 2, the lug E?. being pressed in the opposite direction by the. weaker spring ofthe conductor H8. The movable con tact element |44 isr then midway between the fixed elements 54 and |55 and is out of contact with both of these elements. Movement of the lug 52 downward brings thecontact element it into contact with the fixed element |54. Movement of the lug 52 upward from the position. shown in Figure 2 permits the resilient elementl i8 to spring upward to press the element |44 against the element 55E.

in order to maintain the springs i El?, and |7|l in place during the operation ci the switch, the lugs 5t, 52, 5.4, and 56 may each be notched as at Il' so as to receive a leg of one of the springs and to hold the spring against working away from the wall 2S.

The iixed contact elements are electrically connected with suitable terminals which project from the rear cover of the switch. Thus the elements |45V and Mit are mounted in a metal strip |78 which is bent to a U-shape so that the contact elements face in opposite directions for engagement by corresponding movable elements, and a blade |80 projects up through a suitable slot IZ in the rear cover of the switch so as to receive a complemental electric connector member when the switch is connected in a circuit. Likewise the -xed Contact elements l5@ and 56 are mounted on a metal member |84 having a blade It projecting through a notch |58' in the rear cover plate 34. The -xed elements |52 and i511 are connected by a metal member i9@ to which they are secured, this member having a blade |92 projecting up through a slot 94 in the rear cover 34.

Two representative operating conditions of the switch are diagrammatically illustrated in Figures 8 and 9. Figure 8 shows the positions of the four slides when the button Eil is pushed in so as to align the four notches opposite to this button. In aligning the notches the wedge of the button 80 moves the slides 40 and 44 downward and the slide l-l upward, the slide 42 not being moved since the notch in that slide is normally in alignment with the wedge end of the button 8G. Downward movement of the slide it and its lug 5u permits the conductor il@ to press the mow able contact element |42 against the xed element |58. lDownward movement of the slide f-i with its lug 5! permits the conductor l i4 to press the movable contact element Idil against the fixed element Mii. Upward movement of the slide G5 with its lug 58 permits the conductor H2 to press the movable element |33 against the fixed element Ille. As indicated in the dia" gram in Figure 8, the conductor |22 is permanently connected to a pilot light i955, the conductor Sie is permanently attached to a low heating element |93 and the conductor H is permanently attached to a high heating element 200, the low and high heating elements constituting a heating unit for a range. The conductor H4 is permanently .connectedto a return wire 202.from both of the heating elements 19t and 29u.

When the switch is properly connected in service, the iised contact elements Mt and ll are connected to the low potential wire itil of a threeivi1e power circuit. The fixed elements |523 and it@ are connected to the ground wire Ztl-6 and the fixed elements |52 and ld are connected to the high potential wire 205i. In ordinary power supply sources, there a voltage ci approximately 1104.15 volts maintained hetween the wires 291i and 296 and between the wires tl and 2te?, the voltage between the low wire 26d and the high wire being approximately 22.@230 volts. Thus when the button 2l) is pushed in as indicated in Figure 8, the low element Hit is connected between the ground wire 25S and the low potential wire 2G51, the high unit 2% not being connected. Thus low heat is obtained trom the unit.

When the button l0 is pushed in, the slides take the relative positions diagrammatically indicated in Figure 9, the slides 49 and Lit being ce1-mined upward, the slides E and t being camined downward. As a result oi the upward movement of the slide 4%; the lug 5G pushes against the conductor HE so as to press the contact element la? against the `died element |52. The downward movement of the slide d'2 with its lug pushes against the conductor i so as to the contact element hifi against the .xed element 35d. The downward movement of the with its lug 54 permits the conductor llt to press the element Mil against the xed element tdt. The upward movement of the slide dii and its lug 56 permits the conductor H2 to press the element |36 against the rfixed element |66. Thus the heating elements and 20|] are each connected in parallel between the low potential wire 294 and the high potential wire 2ii8 thus getting the maximum amount of heat from the heating unit. In like manner the notches in the slides 4t, ft2, and are so arranged that when the button 32 is pressed in, the two heating elements 98 and 2M are connected in series in a 11G-volt circuit, this giving the lowest degree of heat obtainable from the unit. When the button 'IS is pressed in, the high element 2M is connected in a 11o-volt circuit. The button 'It connects both heating elements in parallel in a 11G-volt circuit. The button l con nects the low element |95 in a 22Q-volt circuit, and the button l2 connects the high element Eet in a 22o-volt circuit. The notches in the slide 46 are so located that the pilot light is connecte in a circuit every time any of the seven active buttons is pushed in.

I claim:

1. A push-button switch comprising a casing, an elongated slide longitudinally movable in said casing, said slide having a series of V-notches in its forward edge and a lug projecting from its rear edge, a resilient member pressing against said lug in a direction parallel to the movement of the slide, a spring element engaging said lug and opposing a stronger .torce to the pressure of said resilient member, a iixed stop element against which said spring element normally presses, and an actuating member carried by said casing to move said slide and its lug, said actuating member having a wedge portion arranged to enter one oi said `f-notches to cam said slide.

2. A push-button switch comprising a casing, a

slide longitudinally movable in said casing, actuating means operable to move said slide from a normal position, a lug projecting from an edge o1 said slide, a strip of spring metal mounted at one end in said casing and swingable in a plane parallel to the direction of movement of said slide, said strip normally pressing against an edge of said lug, a hair-pin-shaped spring mounted in said casing, stop elements engaging the ends of said spring to hold them closer together than their normal spacing, one leg of said spring bearing against the edge of said lug opposite to said strip to oppose movement of said lug and slide in a direction away from said strip, a contact element carried by the free end of the strip, and a xed Contact element engageable by the movable contact element when said strip is swung.

3. A push-button switch comprising a. casing, a plurality of parallel slides in said casing, actuating means operable to move said slides'lengthwise selectively, a lug projecting from the reai edge of each said slide, resilientl members mounted at one end only in said casing to swing in aplane parallel to the direction of movement of the slides, each said resilient member being normally engaged at an intermediate point by a corresponding lug, springs mounted in said cas ing and arranged to press respective lugs and resilient members toward each other, a contact element mounted at the free end of each said resilient member for movement therewith in a direction parallel to the direction of movement of the slides, and i'ixed contact elements mounted in said casing for contact by corresponding movable contact elements.

4. A push-button switch comprising a casing having a partition wall dening front and rear chambers, said wall having short narrow slots therethrough, a plurality of slides slidably mounted in said front chamber, each slide having a lug extending through one of said slots, a plurality of resilient conductors mounted at one end in said rear chamber, each conductor having a contact element at its free end and engaging one of said lugs to be swung thereby when the corresponding slide is moved, xed Contact elements mounted in said rear chamber for engagement by respective movable contact elements, hair-pin-shaped springs mounted on said wall, stop elements on said Wall engaging the legs of said springs to hold them under tension, said springs bearing against respective lugs in opposition to pressure by said resilient conductors against the lugs, and actuating means in the front chamber operable to move said slides selectively.

' HUGH W. BATCHELLER.

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

UNITED STATES PATENTS Number Name Date 1,152,963 Mueller Sept. 7, 1915 2,354,779 Smessaert Aug. 1, 1944 2,414,307 Johnson Jan. 14, 1947 2,431,904 Andrews Dec. 2, 1947 2,442,768 Garvin June 8, 1948 2,529,374 Caruso Nov. 7, 1950