US2675436A - Switch for electric fans - Google Patents

Description

April 13, 1954 P. G. FRERER 2,675,435

SWITCH FOR ELECTRIC FANS Filed Maron 29, 1952 Patented Apr. 13, 1954 2,675,436 SWITCH Fon ELECTRIC FANS Paul G.`Frer`e`r, Peru, Ill., assignor to Soreng Products, Inc., Schiller Park, Ill., a corporation of Delaware Application March 29, 195.2, Serial No. 279,367

(Cl. 20G-11) 4 Claims.

My invention relates to electric Switch means and more particularly to av multiple contact Switch means of the type such as used for varying the speed of an electric motor. 4

One of the objects of my invention is the provi- Sion of a switch means embodying a contact blade adapted to undergo sharp, engaging and separating movements at it meets with a series of contact terminals so as to minimize the effects of arcing and Wear which are presentin conventional switches wherein the movable contact arm or blade slides over contact terminals in edge to surface engagement.

. A further object of my invention is the provision of a switch means of lthe foregoing character in which the Switch bladejupon making or breaking contact with a contact terminal is caused to be liftedtoward or away4 from the said .terminal, thereby minimizing arcing and wear between the switch blade and the terminal...

Another object of my invention is the provision of a switch means which is simple in construction, economical to manufacture and durable and ef,

ficient in service.

Other and further objects and advantages of my invention will become apparent-from thefollowing description when considered. in connection with the drawings in which Fig. l is an elevational view of an electric fan with a portion broken away to illustrate my invention incorporated in the base. thereof.

Fig. 2 is a cross sectional View of an enlarged scale taken substantially from line 2--2 of Fig. 1 and looking in the direction of the arrows.

Fig. 3 is a cross Sectional View taken substantially on line 3--3 of Fig. 2.

Fig. 4 is a cross sectional View taken substantially on line 4--4 of Fig. 3.

Fig. 5 is a cross-sectional View similar to Fig. 3 but showing the parts in a diierent operative position.

Fig. 6 is a plan View of the switch blade.`

Fig. '7 is a cross sectional view taken on line 7--1 of Fig. 6, and r .Fig 8 is a cross sectional IView taken on line 8-8 of Fig. 7.

Referring to the drawings, the numeral I0 indicates generally an electric fan in the base of which is disposed the switch means of my invention the base being indicated generally by I I. It will be understood, however, that the particular application is merely illustrative of one use Afor the switch means and that myinvention is not to be limited specifically tothe application illustrated; The switch means Il Vof'my invention comprises a mount plate I2V molded of suitable electrically,non-conductive material and provided with a pairof openings for receiving screws I3 by which'` the plate may be mounted in the base of an lelectric fan or at any other desired place. The mount plate I2 may be of any suitable form. that illustrated in the drawings being triangular. The mount plate I2 is provided with an aperture I4 at a point corresponding substantially to the apex of the triangular form, the said aperture being adapted to receive one end of the switch lever I6 hereinafter to be described. The plate I2 is preferably molded with atoothed bed I1 on one surface thereof, Athe toothed bedy having radial serrations I8, asillustrated in Figs. 2 and 4. Additionally, the mount plate I2 isy provided with a plurality of pairs of slots I 9 in concentric relation totheserrations With each pair of slots arranged in substantial alinementwith a trough of a serration I8 as illustrated in Fig. 2. It will be noted that while four' Serrations or teeth I8 are illustrated only threepairs of .slots I9 are provided in themount plate. Interlocked in each pair of slots Iain the manner illustrated in Figs. 3 and 5, is a contact .terminal 2| Yformed of relatively thin gageelectrical conducting material. Each of the contact terminals is. provided with a solder lug 22 for,k connection toa suitable electrical conductor wire.,2'2.a. Eachcontact terminal 2| is related to one position of speed adjustment, as for example, high, medium or low for t-he fan motor. The end tooth or serration Ia is notprovided with an alined contact terminal-2l and thus constitutes the ",Off. position-for the fan motor.

.The lever I6-is formed substantially in longitudinaicross section as illustrated in Figs. 3 and 5 .and includes a boss 23 at one end thereof, the said boss being receivedinthe aperture I4 of the mountplate vI 2 so that the lever is pivotable about the axes of the said aperture in a plane substantially parallel to that of the mount plate. The lever I6 is provided ,with a circular aperture 24 which liS alinedwith the toothed bed I'I of the mount plate and is also provided with a substantially rectangular aperture 2.6. which is alined with thecontact terminals 2 I. YA resilient arm or blade 21, hereinafter tobedes'cribed is secured to thelever I6 by a pin v28 which also Secures the lever to the mount plate. The end of the resilient arm is provided with a solder lug 29 to which an electrical conductor 30 is attached'.

`The resilient arm 21 isformed of resilient electrieallyuconductive material' and includes body portion 3lV and a contact `element 32 at a right angle'to the plane of the body, the said contact element entering into the aperture 26 of the lever and being adapted to engage the contact terminal 2| on the mount plate. As will be seen more clearly by reference to Fig. 7 the body portion 3| has a finger portion 33 struck out from the plane thereof, the said finger portion being connected to the body as at 3|a. It will be apparent that the finger purtion 381 is@ hinged rela.- tive to the body portion 3| and may move rela-- tive thereto as a result of the finger portion being offset from the plane of the body portion. At the* extreme end of the finger portion 33. are late erally directed ears or lugs 34 corresponding'to similarly located cutouts 35. inithebody portion 3|. As a result of the offsetting of. the iingen portion 33 the lugs 34 are moved out of registration with corresponding cutouts 35. in the body. portion as clearly illustrated in Figs. 6` and 7 and, accordingly, the said lugs engage withr the underside of the body portion and effect an elevation thereof. when the. finger portion. 33 is raised in a manner, as will bepresently described. The aperture 24`` in the lever |-.`6.i`s. adapted. tore.- eeive apin 36 having a rounder blunt noselwith. the nose being adapted to engage. in the serra..- tions ofthe toothed bed; The opposite endof the said pin is preferably` reduced insize. to provide a shoulder 31the reduced.` end passing through anaperture in the finger portion 311iJ and the. shoulder 3'! engaging the topside. ofthe said. ringer portion.

The operation of myimproved switch` means should be apparent from theforegoing but briefly stated it is as follows: Whenv the switch is in Off position the lever I6 is aline'd with serration |8a and the pin 36 eng'ages'th'erewith... When the lever I6 is moved' to High speed position immediately adjacent to the Oil position, the. pin 35 is caused to ride to the crestof. the. serration so as to act on the nger portion 33. and. move the same in a direction away from the` plane of the surface ofthe contact terminal.` Movement of the finger portion. 33 in a direction. indicated causes the laterally' directed' lugs 34 thereof to engage against the body portion' 3| intermediate out of contact position illustrated;

in Fig. 5', the latter position corresponding' to one of maximum movement ofthecont'act" member in a direction away from the` plane of a contact' terminal. When the pin 36 reaches" a point just beyond the crest of' al serration, the resilience of the finger portion 33 urges the pin' 33 to follow the contour' of the serration in' a direction to' en'- gage in the trough between two crests' as illustratedv in the solid lines in Fig'. 4. Thus; the iinger portion 33 serves to retain the lever I3' in a position of placement until it is manually dislodged therefrom thus effecting positive' indexing of the said lever. The foregoing action takes place between adjacent contact terminalsso that in moving the switch lever |5 from one contact terminal 2| to another the contactmember. 3'2 is. caused to be sharply moved' away from engage.- ment with a contactterminal almost` mmede.-

Cil

ly upon initiation of movement of the switch lever. After traversing the gap between two adjacent contact `terminals the contact member 32 is caused to be moved into sharp engagement with a succeeding contact terminal. Thus there is substantially no wiping action of the contact member 32 over the contact terminals with a consequent. reduction iniwear andia minimum of arcingm Eurthen. because the finger` portion 33 is normally spaced from the body portion 3| when the switch is in On position effective contact pressure of the contact member 32 on a contact terminal 2| is always maintained.

Various changes.- coming within the spirit of my: invention: mayi suggest themselves to those skilled in ther: art. Hence I do not wish to be limited. to the. specific embodiments described ork uses" mentioned, but intend the same to be merelyr exemplary, the scope of my invention being limited only by the appended claims.

I claim:

1".. An electrical switch comprising a mounting plate.a lever. pivotally attached to said plate, a plurality ofA contact terminals carried on said mountingv plate. a resilient arm having a contact portion andi` movable with said lever, said arm having a resilient finger intermediate said arm and said leverand adapted to engage withsaid arm. camming. surfaces on said plate each intermediate adjacent contact terminals and inwardly of said terminals, a detent pin movable with said lever and? engageable with said cammin'g surface and with said resilient arm, said pin when. moved from a position of rest by said f lever oversaid' camming surface rstmoving said ngerin a' direction toengage said arm to cause the Contact portion thereofv to move in a direction away from the' surface of contact of a contact terminal and" then causing said finger to movesaid contact portion ina direction towards the surface of contact" of' a succeeding contact ternrlnal.A

2: Arr electrical switch comprisingcombinan tiona` plate having a plurality of contact terminals mounted thereon, a lever pivotally mounted on said" plate, c'amming surfaces on said plate each intermediate adjacent contact terminals and inwardly thereof betweenlsaicl terminals and the pivotal connection of said lever, a resilient cond'ucto'r arm having a contact end and supported to" move with said` lever., said contact end being normally urged'in a direction to engage with said contact terminals., a resilient nger connected to said conductor. ann and disposed in a piane spacedl from and intermediate said arm and said lever, said' nger having a. portion engageable with. said arm, a protuberance on said finger arranged to wipe over said camming surfaces whereby said finger is. caused to engage said arm to cause said' contact end in passing to an anijacent terminal` to move away sharply from engagement with. a terminal and then to move towards an adjacent terminal.

3. An'v electrical switch comprising a mounting plate, .a plurality of contact terminals mounted on saidjplate', a lever pivotally mounted on said plate, said plate havingV a toothed bed with the teeth thereof intermediate adjacent contact terminals and inwardly thereof between the terminals and the pivot connection of said lever, a resilient conductor arm supported to move with said lever, said'arm having. a contact end passing through. an aperture in said4 lever and normally. urglcdtinto engagement with a contact terminal, a` resilient finger struckv out of said arm but integrally connected thereto at one end and offset from said arm in a plane spaced from and intermediate said arm and said lever, said nger having a portion engageable with said arm, a protuberance on said nger projecting through an opening in said lever and arranged to wipe over said toothed bed whereby said linger is caused to engage said arm to cause said contact end in passing to an adjacent terminal to move away sharply from engagement with the terminal and then to move towards an adjacent terminal.

4. An electrical switch comprising a mounting plate, a plurality of contact terminals mounted on said plate, a lever pivotally mounted on said plate, said plate having a toothed bed with the teeth thereof intermediate adjacent contact terminals and inwardly thereof between the terminals and the pivot connection of said lever, a resilient conductor arm supported to move with said lever, said conductor arm formed with a nger struck out from said arm and offset therefrom intermediate said arm and said lever, said nger terminating short of said arm and having References Cited in the le of this patent UNITED STATES PATENTS Number Name Date 1,626,463 Harrington Apr. 26, 1927 2,291,249 Nielsen July 28, 1942 FOREIGN PATENTS Number Country Date 605,675 Great Britain July 28, 1948

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