US2639344A - Electric switch - Google Patents

Description

May 19, 1953 E. w. RICKMEYER ELECTRIC SWITCH 2 Sheets-Sheet 1 Filed Aug. 16, 1949 INVENTOR. 77255 ZZ/fickmgg k May 19, '1953 E. w. RICKMEYE'R ELECTRIC SWITCH Filed Aug. 16, 1949 2 Sheets-Sheet 2 0 W. 3 w a r w a 3 INVENTOR. 57'7Z6i Mi lie/57725997; i BY Patented May 19, 1953 UNITED STATES ?ATENT OFFICE 12 Claims.

This invention relates generally to electric switches and has to do more particularly with a switch of the type which is resiliently biased to ward one position and is adapted to be actuated, by foot or hand pressure, to a secondposition to make or break an electrical circuit connection.

An object of this invention is to provide an improved electric switch of the foregoing character.

Another object is to provide an electric switch which may be operated by foot or hand pressure applied thereto, substantially irrespective of the point or direction of application of such pressure on the switch Another object is to provide an electric switch adapted to be=operated by footor handpressure, which switch is adapted to be disposed on a supporting surface such. the floor orthe top or a desk and which switch may be moved readily from. place toplace but which at the same time resists any tendency to slide alongv the surface ble; which. has few moving; parts, which requires no. adjustment of: parts after assembly, whicl'r not likely to get-out-ot order even-thoughsubjected to considerable abuse,;. and which is not subject to. material wearof parts over a long periodof use;

Other objectsan'd advantages-of the'invention will appear from the following descriptiontaken in. connection with the appended drawings;- inwhich I Figure l is a. perspective viewof one embodiment of my invention;

Fig. 2-is an enlarged-top plan View ofthe s-witch of Fig. 1, certain of-theparts: beingibrolten away to show the interior: 0t the switchg.

Fig. B is an-enla'rg'ed, transverse" sectional taken. alongtlie li ne tt of-Figi 1;.

Fig. 4- is. a fragmentary,. enlarged transverse-- sectionallview-taken-along lined-4 oi-Eig. 1;

Fig. 5'.- is' an exploded perspective; view of the interior mechanism of the switch ofFig: 1;

Fig. 6- is a top plan-view, with certain parts broken away, showing; a secondembodiment of my invention;

Fig. 7 is an-en1arged;sectional ViEW tQk-BII along Fig. 8 is a fragmentary, enlarged sectional view taken along line 8-8 of Figl fi; and v Fig.- 9 is exploded perspective view of the interior mechanismof the switch of Fig. 6. u v

The switch of the present invention is adapted for a. large number of applications where it isdesired that the switch be operated by footer hand pressure and particularly" where, it is desired that the switch operate even though no particular care is exercised by the operator as to the direction in which the actuating pressureis applied. One application to which the switch of this present invention is especially well adapted is in connection with sound recording and reproducing machines used in g'ivingand transcrib ing dictation whereinit is desirable to provide a control switch for starting" and stopping the machine, which switch is paced on the floorior foot operation s0 mar ne users hands are for other purposes, asfor example, the operation of a typewriter. &

In accordance with-the present" invention, the switch includes a pair" of contact-carrying memhers which are connected in substantially parallel coaxial relation for relative movement to" ward and away from each other in a direction along their common axis and for universal relative rocking movement". The contact-carrying members are normallyspring biased to a first limit positionin which they are substantially parallel and spaced apart a maximum distance and are adapted to be moved closer together toward a second limit position by the application; of foot or hand pressure exerted against the switch casing from substantially nearly any direction, whereupon the switch members are moved relatively, either in an axialdirection. or are rocked-or both, to bringat least the peripheral portion-s01" the'mernbers closer together; Cooperable electrical contact elements are caried onthe members in a positionto-abut when the members are in one of the two limit positions andtobe separated when the members are moved into the other of the limit positions.

Referring now particularly to Fig. 3 of the drawings, theswitch in one embodiment includes a first contact-carrying member Hi preferably of discoidal form and having a body portion i l and a post portion If? upstandingcentrallyfrom the body portion: The member It is adapted to insulatin-gly carry electrical contact elements hereinafterdescr-ibed and is formed preferably oi insulatingmaterial. For convenience in mann facture; the -member 'i t is-made as a single bo'dy of molded insulatmgmatei'ial, such as hard me: her or a' suitabie'plastic'f The member l O' carries-a -pair of contact "ele men-ts I 3=-of -suitable electrically conductive ma teii'al which" elements are' disposed-on diametri cally opposite sidesnf the'akisof -th'e' n'iember l 0" 3 and spaced outwardly from the axis a substantial distance. The contact elements I3 are carried by a rigid bridge member I4 of electrically conductive material, such as brass or copper, secured to the member Iii by a rivet I5. Preferably, the bridge member is disposed in a slot IS in the member I in order to maintain the former against angular displacement about the axis of the member II). The bridge member I4 serves both to carry the contact elements I3 and connect them electrically and also serves as a retaining element for a second contact-carrying member I! now to be described.

The second contact-carrying member I! preferably is of discoidal shape and of a diameter equal to that of the member Iii. The member I! is adapted to insulatingly carry a pair of contact elements I8 and therefore preferably is itself formed essentially of insulating material. The member I! preferably is formed by a plurality of discoidal members or laminations I9, 2&1, 2I, 22 of insulating material secured together in a stack by a plurality of metal rivets 23, arranged in a generally circumferential pattern. While the laminations I9, 20, 2|, 22 may be formed of any suitable material, I prefer to employ molded material of a known type formed by impregnating paper or cloth with a moldable plastic material, in order to provide the desired strength.

The contact elements l8 are disposed on diametrically opposite sides of the axis of this member and spaced outwardly therefrom a suitable distance whereby when the contact-carrying members II) and H are assembled in operative relation, the contact elements it and I8 are in alignment. Each contact element I8 is carried by a terminal member 24 of electrically conductive material. While the contact element I8 may be formed integrally with the terminal member 24, preferably I form it separately and rivet it to the terminal member. Each terminal member 24 is secured in the contactcarrying member I! by inserting the former between the laminations I9 and 26! before they are riveted together. Each terminal member 24 is formed with a small projection which is adapted to be received in a corresponding recess 26, which conveniently may be formed by perforating the lamination 19, whereby the terminal member is locked against displacement on the member I'd. Also, the contact element I8 preferably is formed as a rivet, the lower head of which enters a recess 21, preferably formed by perforating the member I9, which may provide additional locking effect.

The terminal members 24 extend outwardly from the periphery of the contact-carrying member I! and each is preferably provided with a perforation 28 by which a conductor 29 may be attached.

The contact-carrying member I! is formed with a central, circular opening 30 adapted to receive the post I2 of the other contact-carrying member I0, whereby to permit the contactcarrying members Ill and I! to be assembled in general coaxial, parallel relation, with the con- When the members Ill and I! are assembled in the manner illustrated, the bridge member I4 serves to limit separation of the members l0 and I! in an axial direction and also cooperates with the post portion I2 in preventing transverse separation of the members I0 and I1, However, the members I0 and I! are free to move relatively to a limited extent in a direction along their com mon axis. Also, sufficientclearance is provided tact-carrying member I! assembled over the post portion I2. The laminations 20, 2| and 22 are each formed with diametrically opposed radially extending notches 3| which receive the radially extending portion of the bridge member I4. It will be understood, of course, that the contactcarrying members If! and I! are assembled prior to the attachment of the bridge member I4 to the contact-carrying member I0.

between the post portion I2 and the central opening 30 to permit the members I0 and I! to be rocked relatively in any direction. Thus, the members I0 and I! may either be moved axially or rocked, or both, simultaneously, to a limited extent. I

The contact-carryingme'mbers I0 and I! are normally urged resilientlytoward the first limit position in which they are disposed substantially parallel and are a maximum distanceapart (as in Figs. 3 and-4). To this end, a pair of coil springs 32 are provided (Fig. 40' which are received in diametrically opposed recesses 33 in the contact-carrying member I! by perforations 34 and 35 formed in the laminations I9, 20 and 2I. Each of the springs 32 bears at one end against the body portion I I of the member I 0 and at the other end against the lamination 22 of the member H. The springs 32 are located on a diameter of the member H which extends perpendicularly to the diameter in which the contact elements I8 are located.

When the contact-carrying members It! and I! are in their first or normal limit position, as established by the biasing action of the spring 32, the contact elements I8 and I3 are in contact and an electric circuit is established from one of the conductors 29 through the corresponding terminal member, the contact elements I8 and I3 and the bridge member I4 to the other set of contact elements i3 and I8 and the terminal 25 carrying the latter to the second conductor 29. Relative movement of the contact-carrying members It! and I? out of the aforesaid limit position causes separation of' one or both of the sets of cooperable contact elements I3 and It, thereby interrupting the electrical connection between the two conductors 29. Such separation of the contacts may be accomplished eitherbythe relative movement of the 'contaotwarryingmembers I0 and IT toward each otherin a direction along their common axis, or by relative rocking movement of the contact-carrying members Ill and IT, whereby the latter are brought closer together at least at one peripheral portion thereof. Such relative movement of the contactcarrying members I0 and I! as will effect separation of one orboth of the sets of contact elements may be produced by applying opposed forces on the contact-carrying members from any direction, except in a plane passing perpendicularly to the common axis-of these members. Thus the circuit which is completed by the switch when in normal condition may be interrupted by disposing the switch on a supporting surface, with either of the contact carrying members uppermost, and depressing the uppermost member. The switch also may be actuated by squeezing it between the fingers although the previously described mode of operation is generally preferred.

It will be seen that where the uppermost contact element is'moved toward the other in a direction along the common axis of the contactcarrying members, both sets of contact elements are separated. On the other han.d',.where the.

out of the above-described first limit position and toward a secondlimit position in which the members 58 and BI are at a minimum distance apart. It will be seen that where the members 50 and are moved out of the first limit position and into a second limit position wherein they remain in parallel relation, all of the contact elements 52 will contact the corresponding contact elements 62. However, because of the 120 circumferentiai spacing of the contact elements on each contact-carrying member at least one set of cooperable contacts 52 and 62 will contact even if the contact-carrying members are rocked out of the first limit position and toward a second limit position, instead of being moved axially.

Means are provided for preventing relative rotational movement of the contact-carrying members about their common axis, but which means does not interfere with the desired axial relative displacement or relative rocking movement of the contact-carrying members. Such means includes a plurality of upstanding projections 15, it and ll on the member 50 and projections 18, is and ti) on the member 5|. The projections and it are arranged as a pair, being closely spaced at a distance sufficient to freely receive the projection l8 therebetween when the members are assembled and the projections 19 and till also are paired, being spaced in an analogous manner to receive the projection ll therebetween. The projection T! is disposed at an angle of 120 around the circumference of the member 50 from the space between the projections l5 and i6. As explained above, the projections it and 8t and the projection l8 on the member 5| are complementally arranged to the projections on the member til. Accordingly, while the several projections serve to prevent any substantial relative rotational movement of the members 5|] and 5| about their common axis the arrangement of the projections is such as to permit the members 58 and 5| to be moved relatively in an axial direction or rocked relatively.

In connection with the foregoing, it will be noted that while the projections 71 and 18 extend into the spaces between the pairs i9, 80 and 15, it respectively, yet the projections are of such height that sufficient clearance is provided when the members 50 and 5| are in normal position to permit the desired axial movement of those members. Moreover, the spacing between the projections of each pair is sufiicient to permit the desired rocking movement or the axial movement.

The switch mechanism of the embodiment illustrated in Figs. 6 to 9 preferably is inclosed in a casing so similar to the casing illustrated and described in connection with the first embodiment of the invention.

From the foregoing it will be seen that the present invention provides a new and improved electric switch which is capable of use in a large number of applications where it is desired to operate the switch by continued application of root or hand pressure to maintain a certain circuit condition. The switch is especially well adapted for controlling the operation of an office dication recording and reproducing machine.

- Because of the novel structure the switch may be operated by foot or hand pressure applied from almost any direction and without particular attention being paid to the exact point or direction of application of force. For this reason the switch is well adapted for use as an emergency switch which may be operated by the knee or elbow, for. example.

The switch is simple and inexpensive to manufacture but at the same time may be made very strong and rugged. The construction is such that the switch is not easily damaged and may even be stepped on by the operator without damage.

The switch mechanism is inclosed and substantially sealed against contact with dirt or moisture. Thus the switch may be disposed on a dirty or moist floor without damage to the switch. Also, since the mechanism is inclosed in air sealed, moisture proof and insulating casing there is little danger due to sparking. Moreover there is little chance of the operator receiving an electric shock from the switch, even where it is located on a moist floor.

The switch may be constructed so as to be operated by a relatively light force and a relatively slight movement of the relatively movable parts. Thus the operator may obtain the desired response in the electric circuit quickly and with a minimum of movement of the foot or hand. On the other hand the switch may be made so that the operating pressure required may be rela tively heavy, in cases where this type of switch is desired.

There are but few moving parts in the switch and such parts are not subject to undue wear. Therefore, the switch is capable of use over a long period without repair or replacement. It does not require any adjustment after assembly and no servicing or adjustment during use.

I claim:

1. An electric switch comprising a pair of discoidal shape, contact-carrying members disposed normally in generally coaxial parallel relation. guiding and retaining means connecting said members for relative movement toward and away from each other in a direction along their common axis and for universal relative rocking movement between a first limit position in which said members are substantially parallel and at a maximum distance apart and a second limit position in which said members are at a minimum distance apart at least at one peripheral portion, spring means urging said members toward said first limit position, and contact elements insulatingly carried by said members respectively, outwardly of their centers, positioned for mutual abutment when said members are in one of said limit positions and separation when said mem bers are in the other of said limit positions, and a generally discoidal shape casing of flexible, resilient insulating material surrounding and enclosing said contact-carrying members and the contact elements carried thereby, said casing having normally parallel, generally flat opposite portions closely fitting respective ones of said contact-carrying members and interengaging peripheral portions surrounding the periphery of said members, said casing being adapted to be flexed and compressed by pressure upon any peripheral portion thereof for moving the corresponding peripheral portions of said contactcarrying members relatively together, and being adapted to return to its normal condition upon release of said pressure, said casing being imperforate except for a portion having an opening adapted to receive conductors leading into said casing.

2. An electric switch comprising a first generally discoidal contact-carrying member having an upstanding post extending centrally therefrom in an axial direction, and a second contact-carrying member having a central opening freely receiving said post for guiding said members for axial relative movement and relative universal rocking movement, spring means urging said members apart, a bridge member secured to the outer end of said post and extending radially outwardly beyond said. post in two opposite directions and across an adjacent underlying portion of said second contact-carrying member to limit separating movement of said contact-carrying members and thereby establish a limit position. of said contact-carrying members, a first pair of contact elements carried by said bridge member outwardly of said post and a second pair of contact elements carried by the underlying portion of second contact-carrying member in positlon. to abut said first contact elements respectively in said limit position, said second contactcarrying member having a circumferential portion disposed axially beyond said post and bridge member when the two contact-carrying members are a maximum distance apart whereby to enable the members to be moved relatively toward each other in response to pressure applied to any portion of the opposite sides of the members.

3. An electric switch comprising a first contact carrying member having a generally cylindrical central portion and an annular flange extending outwardly therefrom, a second contact-carrying member of generally cylindrical form disposed in coaxial parallel relation to said first contactcarrylng member having a central opening extending axially therethrough and receiving said central portion therein for axial relative sliding movement between said contact-carrying members. said second contact-carrying member having two recesses extending from its outer face to short of its inner face and opening into said central opening throughout their lengths, on diametrically opposite sides thereof, a first set ot contact elements carrieclby said second contact-carrying members in said recesses, and a second set of contact elements carried by and radially outwardly from said central portion on diametrically opposite sides thereof and disposed in said recesses in position to abut said first contact elements, and spring means urging said contact-carrying members apart to effect abutmerit of said contact elements.

4. An electric switch comprising a first contactcarrylng member having a generally cylindrical central portion and an annular flange extending outwardly therefrom, a second contact-carrying member of generally cylindrical form disposed in coaxial parallel relation to said first contactcarrying member having a. central opening extending axially therethrough and receiving said central portion therein for axial relative sliding movement between said contact-carrying members, said second contact-carrying member having two recesses extending Iroznlts outer face to short of its inner face and opening into said central opening throughout their lengths, on diametrically opposite sides thereof, a first set of contact elements carried by said second contactcarrying members in said recesses, and a second set of contact elements carried by and radially outwardly from said central portion on diametrically opposite sides thereof and disposed in said recesses in position to abut said first contact elements. said second contact-carrying element having recesses extending from its inner face to short of its outer face, and springs disposed in said last-named recesses for urging said contact carrying members apart to effect abutment of said contact elements.

5. An electric switch comprising a pair of sub- Pil ' stantially identical, enerally discoidal contactcarrying members disposed in spaced, coaxial and generally parallel relation, means for guiding and. retaining said contact-carrying members including a guide member extending axially between said contact-carrying members and on which at least one of said contact-carrying members is universally rockable and axially slidable, spring means between and centrally of said contactcarrying members, urging them apart, at least three contact elements carried on each of said contact-carrying members, outwardly of the center thereof and circumferentially spaced uniformly, with the contact elements on each contactmarryin member being aligned and in opposed relation with those on the other contactcarrying member whereby at least one pair of contact elements abuts when the contact-carrying members are urged together by either relative rocking or axial. movement, and interengageablo means on the members operative for restraining the member against relative rotational movement in both directions.

6. An electric switch comprising a pair of generally discoidal contact-carrying members disposed in spaced, coaxial and generally parallel relation, means for guiding and retaining said contact-carrying members including a guide member extending axially between said contactcarrying members and on which at least one of said contact-carrying members is universally rocltable and axially slidable, spring means between and centrally of said contact-carrying members, urging them apart, at least three contact elements carried on each of said contactcarrying members, outwardly of the center thereof and circumferentially spaced uniformly, with the contact elements on each contact-carrying member being aligned and in opposed relation with those on the other contact-carrying member whereby at least one pair of contact elements abuts when the contact-carrying members are urged together by either relative rocking or axial movement and projections extending from each contact-carrying member toward the other contact member at points outwardly from the centers thereof with the projection extending from one contactwarrying member being circumferentially adjacent the projection extending from the other contact-carrying member to prevent relative rotational movement of said contactcarrying members about their common axis.

7. An electric switch comprising agenerally cylindrical switch mechanism including a pair of contact-carrying members connected for relative movement toward and away from each other and having contact elements thereon adapted to abut in one position of said contact-carrying members and to be separated in another position of said contactwarrylng members and spring means urging said contact-carrying members apart, and a casing of flexible resilient, insulating and moisture proof material surrounding and inclosing said switch mechanism, said casing having a generally cylindrical inner chamber in which said mechanism snugly fits, said casing being adapted to be compressed for moving said contact-carrying members toward each other, said inner chamher being effective for retaining said contactcarrying members centrally in the casing. said casin having an annular chamber radially outwardly of and opening throughout its circumference into said inner chamber for receiving conductors connected to said mechanism, and an outlet extending from said outer chamber for the conductors.

8 An electric switch comprising a pair of contact-carrying members disposed in coaxial, gem

erally parallel relation, means connecting said members for relative universal rocking move- 'ment, said members having portions in telescoped relation, a pair of contact elements carried by each contact-carrying member outwardly and on diametrically opposite sides of the center thereof, and in alignment with the contact elements of the other contact-carrying element for abutment therewith when said contact-carrying members are urged apart, all of the contact elements being disposed radially inwardly of the periphery of the members, and spring means ur ing said members apart to resiliently and yieldingly maintain said contact elements in mutual abutment.

9. An electric switch comprising a pair of discoidal shape contact-carrying members disposed in coaxial, generally parallel arrangement, means connecting said members formovement toward and from each other and for relative universal rocking movement, a set of three contact elements carried by each contact-carrying member outwardly of the center thereof at circumferentially equally spaced points, the contact elements of each set being disposed in alignment with those of the other set respectively for abutment between at least one contact element with the aligned contact element when said. contact-carrying members are rocked, spring means urging said contact-carrying members apart to resiliently and yieldingly maintain all of said contact elements out of abutment, and a casing of electrically insulating and waterproof material surrounding and inclosing said contact-carrying members, said casing having a generally discoidal overall shape providing two external generally parallel major surfaces both shaped so that either surface is effective for stably supporting said switch on a flat surface for actuation by foot pressure applied from any angle in the direction of the supporting surface, said casin being formed of resilient, flexible, relatively soft, rubber-like material having a high coefficient of friction against a flat surface.

10. An electric switch comprising a pair of discoidal shape, contact-carrying members disposed normally in generally coaxial parallel relation, said contact-carrying members being of substantially identical peripheral outline, guiding and retaining means connecting said mem here for relative movement toward and away from each other in a direction along their common axis and for universal relative rocking movement between a first limit position in which said members are substantially parallel and at contact elements carried thereby, said casing including substantially identical opposite portions having recesses receiving respective ones of said contact-carrying members, said opposite portions of said casing being normally parallel and adapted to be flexed and compressed by pressure upon any peripheral portion thereof for moving the corresponding peripheral portions of said contact-carrying members relatively together, and being adapted to return to normal condition upon release of said pressure, said casing being imperforate except for a portion having an opening adapted to receive conductors leading into said casing.

11. An electric switch comprising a pair of discoidal shape contact-carrying members having contact elements thereon, guiding and retaining means connecting said members for relative movement toward and away from each other and universal rocking movement between a contact engaging position and a position in which at least certain of the contacts are disengaged, spring means urging said contact-carrying members apart and into one of said positions, and a casing of electrically insulating and waterproof material surrounding and inclosing said contactcarrying members, said casing having a generally discoidal overall shape providing two external generally parallel major surfaces both shaped so that either surface is effective for stably supporting said switch on a fiat surface for actuation by foot pressure applied from any angle in the direction of the supporting surface, said casing being formed of resilient, flexible relatively soft,'rubber-l-ike material having a high coeilicient of friction against a flat surface;

12. An electric switch comprising a pair of generally discoidal contact-carrying members disposed inspaced, coaxial and generally parallel relation, means for guiding and retaining said contact-carrying members including a guide member extending axially between said contactcarrying members and on which at least one of said contact-carrying members is universally rockable and axially slidable, spring means urging the contact-carrying members apart, a plurality of contact elements carried by each of said contact-carrying members, between the center thereof and circumferentially spaced uniformly, with the contact elements on each contact-carrying member being aligned and in opposed relation with those on the other contact-carrying member whereby at least one pair of contact elements come into and out of contact in response to relative movement between the contact-carrying members by either rocking or axial movement, and interengageable means on the members op erative for restraining the members against relative rotational movement in both directions.

ERNST W. RICKMEYER.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1 804,389 Dow Nov. 14, 1905 1,256,210 Dean Feb. 12, 1918 1,670,649 Brown May 22, 1928 1,716,373 Ellis June 11, 1929 2,409,483 Gandelot Oct. 15, 1946 2,440,943 Gonsett et a1 May 4, 1948 2,516,584, Parr July 25, i)

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