US2608631A - Electrical switch - Google Patents

Description

A118- 26, 1952 w. P. GALLAGHER Er AL 2,608,631

ELECTRICAL SWITCH Y original Filed oct. e, 1947 mma- Patented Aug. 26, 1952 ELECTRICAL SWITCH William ncauagher ana can Weber, chicago, i Ill., assignors to International Register Company, Chicago, Ill., a corporation of Illinois Original application October 6, 1947, Serial No. 778,104. Divided and this application April 8, 1949, Serial No. 86,324 l l The present invention relates to electrical switches of1 general utility type, such as may be used for controllingdll or 220 volt heating, lighting or power circuits.

The present application is divisional of our copending application, Serial No. 778,104, filed October 6, 1947, which is directed primarily to an improved automatic timing mechanism for controlling the heating circuits of electric stoves, electrical ovens and the like. In that earlier application, we disclosed the present electrical switch as being responsiveto the automatic timing controls for closing and opening the heating circuit of the stove at preselected times. While the present electrical switch was devised particularly for use in that automatic timing mechanism, and functions very satisfactorily in that mechanism', the switch is not limited to such use.

One of the objects of the invention is to prof vide a simple, inexpensiveelectrical switch which will produce a relatively large, quick-opening movement of the switch .contacts in response to a relatively small range` `of movement of the switch actuator. In-thev above mentioned automatic timer for electric stoves 'and the like, the actuating motion is imparted or translated from the timing controlslto the switch assemblies through a multiple stepirotating cam. Our improved switch is uniquelyadapted to this cam type of operation, butis not necessarily limited thereto. i r;

Another object of the-invention is to provide a utility switch of the above general type which is extremely simple and inexpensive t0 assemble.

In arriving at a low cost of production, the item of cost of assembly can be just as important, or more important, than cost of materials, or cost of fabrication into switch parts. Our improved construction of switch can be quickly `and easily assembled intoa complete, self-contained unit which can be stocked as such, and `thereafter assembled in the general assembly with the automatic timing mechanism.`

Other objects, features'and advantages of the invention will appear from the following detailed description of one preferred embodiment thereof, In the accompanyingdrawlng illustrating such embodiment:

Figure 1 is a fragmentary plan view illustrating our improved switch on an enlarged scale, and showing the switch actuating cam in dotted lines;

Figure 2 is a longitudinal, sectional view through the switch assembly, taken approximately on the plane of the line 2-2 of Figure 1;

i4 claims. (01.200-153) Figure 3 is a detail, sectional View taken hori- Zontally on the plane of the line 3 3 of Figure 2;

Figure 4 is a detail, sectional view taken vertically on the plane of the line 4--4 of' Figure 3;

Figure 5 is a fragmentary, detail View corresponding to a section taken approximately on the plane of the line 5-5 of Figure 2;

Figure 6 is a fragmentary, plan view illustrating the actuating cam in greater detail; and

Figure 7 is a fragmentary, detail view of a modified construction of switch blade.

The switch is assembled upon a base plate H8 composed of any suitable insulating material.

`In accordance with the'disclosure in ourprior application, Serial No. 778,104, we have shown the switch as `being actuated by a rotatable or oscillatable cam |22 mounted upon a switch actuating shaft III. This cam is shown as having four switch actuatingpositions formed in its periphery, viz.a` cam valley |54 for closing the switch, a cam hump |5`5for opening the switch, a cam valley |56 for closing the switch, and a cam hump |51 'for opening the switch. Riding on these camfformations isi a cam following pin |59 which projects laterally from the end of a switch actuatingplate or slide bar IBI. It will be understood that other operating mechanisms may be employed for actuating the switch. For example, any appropriate operating instrumentality can be employed which will impart motion to thepin |59 comparable to that imparted by the cam |22.

The switch actuating plate or slide bar |6| is composed of insulating material, such as Bakelite and is mounted for endwisze reciprocating motion parallel to the surface of the base plate IIB, but spaced slightly therefrom. The switch actuating shaft passes down through a longitudinal slot |62 in the plate or slide bar |6|, and establishes a point of guidance for guiding the to and fro motion of the plate |61. Referring to Figure 2, the lower end of the shaft ||I has a reduced portion ||6 which is seated in a bearing ferrule |l'l set into the insulating base plate ||8 ofthe electric switch. The shaft can rotate in this bearing-.ferrule ||1, andin the aforementioned adaptation to an automatic timing mechanisml the-shaft could tilt slightly in this bearing ferrule. -This'ferrule comprises an a boss portion |I1c, and with a retaining iiange ||1cZ projecting from the upper portion thereof. The boss portion bears against the top oi. the base plate IIS, and the annular retaining fiange guides or coniines the yoke to which the tension springs are connected, as will be later described.

The slide plate |51 has T-shaped cross arms 63 projecting outwardly to the sides and overlying the movable switch blades. These switch blades, designated |S4, are of angular or sub stantially L-shaped formation carrying movable contacts |65 on the inward sides of their outwardly diverging ends Ia. These movable contacts |85 are adapted to engage with stationary contacts |56 carried by stationary terminals |51 Y rectangular openings in the base plate i8 and secured to the insulating base plate'of the-switch. Y

The switch blades are adapted to have rocking movement about the outer corners iii of terminal blocks |58. The inside corner angle |1| at the angle bend'of each blade has rocking movef ment on such shoulder edge |58 of its companion terminal kblock itt". Current is conducted to the movable switch blade `through this terminal block |68 and through this rocking edge contact established at |68 -|1'|.

projecting from'the cross arms |53. When the switch actuating plate or slide bar I6! is shifted to the right, motion is transmitted through the humps |12 to the inwardly extending arms |6419 of the switch blades for rocking theblades to open circuit positions.

Tongues |14v punched inwardly from the outer arms '|5405 of the switch .blades serve as attachment hooks to which the 'outer ends of tension springs |15 are connected. These tongues alsov function as guiding and retaining elements for the Vswitch blades by extending into U-shaped guide spaces |16 formed in the outer surfaces of the terminal blocks |68, asishown in Figures 3 and 4. Similar U-shaped guideways |18 are Vformed in theinner sides or edges of the terminal blocks |63 for receiving guide wings `|19 projecting from the plate itl This arrangement vestablishes lateral guidance'for'the left hand end of the plate IGI. The inner ends'of the tension springs |15 are hooked to hoolrends on an 'insulating yoke 18| which Vhas rockable bearing contact against the boss portion ||1c under the coniining hange Hl'd of the bushing or ferrule 'i I1. The tension springs |15 perform the two- 'fold function of normally holding the .movable switch contacts |65 pressed iirmly against the stationary switch contacts |66, and also of holding the corner angles `|1|'of the switch blades pressed firmly against the corner edges |58 of the terminal blocks |68 foreffective current conduction through these lines of rocking contacts. The T-shaped cross armsA `|63 of the switch actuating slide plate |6| areformed with downwardly l turned sloping-ends |63 which perform the twofold function 'of stop members for limiting the outward swinging movement of thecurrent conducting legs Itllc of the lswitch blades, as indicated in dotted lines, and lwhich also serve as i The inwardly bent c arms |66?) of the blades bear against A,humps .|12

conning members for preventing accidentaloutare headed or crimped over on the under side thereof, as indicated at |81 in Figure 4. Threaded bores ISS extend upwardly through each of these terminal blocks for receiving terminal screws adapted to be inserted into the terminal blocks from the back side of theA base plate |3 for connecting conductors to these terminal blocks. The construction illustrated affords a single throw, double pole switch, but it will be understood that the invention might also be embodied in a single throw, single pole switch, or even in a double throw switch. f

In the embodiment shown in Figures 1 and 3, the tongues |14 Aare punched out of the switch blades with .the free ends of the tongues pointing toward the switch actuating legs |645 of the switch blades. In the alternative construction illustrated in Figure 7, this is reversed so that the free end of the tongue |14 is bent inwardly toward the current conducting leg Hita of the switch blade.

With regard to Athe assembly of this improved switch, it will be seen that no screws, rivets, or other fastening devices are necessary for holding the switch plate ll, switch blades Itri, springs |15, .or Ayoke vIt! in assembled relation. One simplified method .of assembling these parts is to place the yoke IBI :under the retaining iiange lid, connect the spring |15 from this yoke to the tongues '|14 of the switch blades, and then temporarily place the switch blades in outwardly disposed positions. with the actuating arms |645 bearing yon the rockeredgesvlt, and spaced outwardly sufficiently to permit the guide Wings |13 to pass therebetween. Thereupon, the switch actuating .plate VISI is `slid inwardly from the left so as to Vhave .the guide wings.` |1| move into the guide ways |18 in the pivot terminal blocks iit.

:slot |62 iis dropped down over the ferrule shank |1112, thereby preventing lateraldisplacement of the switch plate to the left. This practically com-l p'letes Ythe assembiyof the switch; the 'actuating camxlzf can be included in the assembly at this time, or at va"later2-staf.,fe when the assembied switch is included inthe timing mechanism.

While we Vhave 'illustrated and described what we regard 'to be the preferred embodiment of our invention, nevertheless it will be understood Vthat such is merely exemplary and that numerous modicationsand vrearrangements may bev made therein without departing `from the Vessence oi the invention. Y

W e claim:

l.. In lan.. electric switch, the Vcombination Aof a T-shaped actuating plate of -insulating material, means mounting said plate for endwise reciprocation, a rotary actuating member,` follower means responsive to said actuating member for reciprocating said plate, apair of movable contact blades, one to each side of said actuating plate, said blades comprising 'bars having inwardly extending actuating ends and angularly extending 'contact' ends, movable contacts carried by said angularly extending ccntact'ends, stationary contacts cooperating with said movable contacts, stationary Supports'on whi'chsaid contact blades have -rocker mounting, actuating `surfaces ,onsaidji -shaped `actuating plate adapted to engage'said Yactuating ends of said blades and to cause rocking movement of said `blades, and spring means :connected with said blades tending to oppose such latter movement.

Inan electric switch, the combination of a switchblade, a pivot terminal therefor, saidblade comprising two angularly extending portions defining an inside corner angle therebetween, said inside corner angle having rockable pivoting engagement against said pivot terminal, a movable contact carried by one of said angularly extend- Ving portions of said switch` blade, a stationary contact adapted to be engaged by said movable contact, spring means normally holding said contacts closed, and a slide bar switch actuator adapted to press against the other of said angularly extending portions in a direction toward said pivot terminal for actuating said switch blade through the other of said angularly extending portions.

3.'In a switch, the combination ofa switch blade, a pivot terminal therefor having a fulcrum edge, said blade being Substantially l.- shaped comprising two angularly extending portions defining an inside corner angle therebetween, said inside corner angle having rockable pivot mounting againstsaid fulcrum edge of the pivot terminal, a movable contact carried by one of said angularly extending portions of said switch blade, a stationary contact adapted to be engaged by said movable contact, spring means holding said inside corner angle pressed against said fulcrum edge and also normally holding said contacts closed, said inside corner angle and fulcrum edge establishing a current conducting path between said pivot terminal and said switch blade, and a slide bar type of actuating means operative to apply pressure to the other of said angularly extending portions for actuating said switch blade to open circuit position.

4. In a switch, the combination of a switch blade, a pivot terminal thereforcomprisin'g a fulcrum edge, said blade being substantially L- shaped comprising two angularly extending portions deiining an inside corner angle'therebetween, said inside corner angle having rockable pivoting engagement against said fulcrum edge, a movable contact carried by one of the angularly extending portions of said switch blade, a stationary contact adapted to be engaged by said movable contact, spring means holding said inside corner angle pressed against said fulcrum edge, said inside corner angle and fulcrum edge establishing a current conducting path between said switch blade and said pivot terminal, and actuating means operative to apply pressure to the other of said angularly extending portions for actuating said switch blade.

5. In a switch, the combination of a switch blade, a fulcrum terminal therefor comprising a fulcrum edge, said blade comprising a current conducting arm and a switch actuating arm extending at an angle to each other to deiine a corner angle therebetween, the inner surface oi. said corner angle having rockable engagement against the fulcrum edge of said fulcrum terminal, a movable contact carried by said current conducting arm, a stationary contact adapted to be engaged by said movable contact, and reciprocable switch actuating means operable to transmit a reciprocable switch actuating motion to said actuating arm, said reciprocable switch actuating means comprising stop means for limiting the outward swinging movement of said current conducting arm.

6. In a switch, the combination of a switch actuating slide bar having a pair of laterally extending arms, a pair of switch assemblies actuated by said pair of arms, each of said switch assemblies comprising a switch blade, a fulcrum terminal therefor havinga 'fulcrum edge, said bladeY comprising two angularly extending portions deiining a corner'angletherebetweengsaid corner angle having rockablef fulcrum `engagement againstthe fulcrum edge of said terminal, a movable contact carriedbysaid'switch blade, a stationary contact 'adapted to be engaged with said movable contact, said pair of 4laterallyextending arms on said switch' actuating slide bar beingarranged `to transmit switch opening motion to said pair of blades, and tension springs connected with saidp'air of switch blades serving to hold said contacts closed, said blades pulled into fulcrum engagement against said fulcrum edges, and said slide bar shifted to one position.

rI. In a switch, thev combination of a T-shaped switch actuating plate mounted for endwise shifting movement, a pair of substantially L-shaped switch blades adjacentthe sides of said plate and arranged to be actuated by the cross arms of said T-shape'd plate, afulcrum terminal for each switch blade, each bladecomprisingan inside angle portion adapted to have rockable fulcrum engagement against said fulcrumterminal, the cross arms of said T-shaped plate exerting switch actuating pressure against said blades in a direction to hold said inside 'angle portion pressed against said fulcrumterminal-an'd contacts controlled by said switch blades.` Y

8. In a switch, the combinationfofa pairA of substantially L-shaped'switch blades having movable contact portions, 'stationary'contacts adapted to be engaged by said movable "contact portions, a pair of pivot `terminals for saidswitch blades, said switch blades having pivot mounting on said Divot terminals at the inside angle of their ysubstantially L-shaped formation, andHaT-shaped switch actuator mounted forreciproatory movement between said s'witchblades and having its cross arms arranged to actuate said switch blades by exerting pressure against said blades in a direction toward said pivot terminals.

9. In a switch, the combination of a pair of substantially L -shaped switch blades having movable contact portions, stationary contacts adapted to be engaged by said movable contact portions, a pair of pivot terminals for said switch blades, the inside angle of said substantially L-shaped switch blades having rockable pivot bearing against said pivot terminals, a T-shaped switch actuating plate mounted for reciprocatory movement between said switch blades and having its cross arms arranged to actuate said switch blades, a yoke mounted under said switch actuating plate, and springs operatively connected between said yoke and said switch blades tending to move said switch blades to closed position.

10. In a switch, the combination of a pair of switch blades having movable contacts, stationary contacts adapted to be engaged by said movable contacts, a pair of pivot terminals for said switch blades, each of said blades comprising a current conducting armand a switch actuating arm extending at an angle to each other to define a corner angle therebetween, said corner angle having rockable engagement against said pivot terminal, and a T-shaped switch actuating plate mounted for reciprocatory movement between said switch blades, said T-shaped switch actuating plate havingits cross arms arranged to transmit switch opening movement to the switch actuating arms of both blades, and having angularly projecting ends operative to engage the current 11.V In an electric switch, the `combination of a switch blade, -a'fulcrum terminal therefor com" .prising a fulcrum edge, ,said blade Acomprising a current conducting arm and a switch actuating arm extending 'at y,ani-angle tol each other in a substantially L-'shaped formation to define alcorner angle therebetween, s aid cornerl angle having -rockable engagement against the fulcrum edge of said fulcrum terminal, a Aconi-"ming slot formed in said fulcrum terminal, ,a conningflug projecting from said switch blade and engaging in said conning slot, and a switch actuator arranged to transmit switch Aactuating Pressure to said switch actuating arxn,.s aid :switch actuator comprising confining means for'preventing accidental displacement'of said confining lugs from saidconfiningslots.

-1'2,.1In a ,-switch, the combinationpof a switch blade, vafulcrumterminal therefor comprising a Vfulcrum Iedg, ,Sad blade comprising a current conducting ,arm and ,a switch actuating `arm extending at an angle to each `other in a subsstantially L-'shaped formation to define a corner angle therebetween, said corner anglehaving rockable .engagement against theL fulcrum edge of said fulcrum lterminala movable-'contact carried by said current :conducting arm, a stationary contact adapted to be engaged by said -movable contact, a conning slot formed -in -said fulcrum terminal, a confining lug projecting from `said switch blade and vengaging l-in said confining slot, and spring vmeans connected -to said conning 'lug normally tending toihold said contacts closed.

13. In a switch, the combination of -a pair of .Switch blades having `movable switch contacts, a pair of stationary switch contacts adapted to be engaged withsaid movablecontacts, a pair of pivot terminals for saidswitch -blades havingconning slots formed in `their outer surfaces and guard slots formed Vin their inner surfaces, .said blades having confining lugs engaging in said confining slots, and Aa switch actuatingfslide plate having guide wings engaging in said guide slots andarranged-tcactuate said switchblades.

14. In a switch, the `combinationof a Vrotatable 4switch :actuating shaft, a ,cam on said shaft, Va lcam followerresponsive to said cam, ,a T-shaped switch actuating plate towhich said cam follower is secured, -said switch actuating plate `having ka guide slottherein through which said shaft extends,.apair of switch blades, said switch blades having movable switch contacts adapted to engage with-stationary switch contacts, separate fulcrum terminals forsaid switch blades, each of said fulcrum `terminals comprising a fulcrum edge, each -ofsaid ,switch blades comprising a current conducting arm and a switch actuating arm extending at an angle to each-other to vdeiine a corner angle therebetween, said corner vangle having rockable engagement against the fulcrum edge .of said fulcrum terminal, said current conducting arm carrying said movable switch contact, the cross r,armsof said T-shaped switch actuat ing plate being arranged to transmitgswitch opening motion'to the switch kactuating arms of both switch blades, and spring means normally ktending to vholdfsaid contacts closed and to hold said corner angles pressed against said fulcrum edges. -V -WTLLIAM P. 'GALLAGHER CARL WEBER.

REFERENCES .eirnn The following references are of record in the 'die of this'patent: f

UNITED STATES PATENTS Number Name p Date 789,572 AStauifer May 9, 1905 1,165,192 McMllion Dec. 21, 1915 1,215,807 Huff l Feb. 13, 1917 1,390,492 Burnham i s Sept. 18, 1921 1,749,200 Van Valkenburg l/lay 4, 1930 1,991,718 ,Armstrong j.- Feb. 19, 1935 2,248,362 Krieger July 8, 1941

Images