US1731932A - Electric switch - Google Patents

Description

Oct. 15, 1929.

G. J. MEUER 1,731,932Y

ELECTRIC SWITCH Filed Feb. 10, 1926 ATTORNEY Patented Oct. l5; 1929' UNITED STATES PATENT OFFICE GEORGE il'. NEUER, 0F MILWAKEE, WISCONSIN, ASSIGNOR, BY MESNE ASSIGNMENTS, T CUTLER-HAMMER, INC., A CORPORATION OF DELAWARE ELECTRIC SWITCH Application led February rlhis invention relates to improvements in electric switches, and more particularly to improvements in rotary snap switches for concealed mounting in canopies or the like.

a An object of the invention is to provide a switch of the above character of extremely simple and compact construction.

Another obj ect is to providel improved means for insuring a snap action of the switch io in making or breakinggan electric circuit.

Another object is to provide a switch having a relatively small number of parts, together with improved means for holding the several parts in assembled relation.

`Other objects and advantages of the invention will hereinafter appear.

lin the accompanying drawing l have illustrated an embodiment of my invention which will now be described7 it being understood 29 that the invention is susceptible of other embodiments without departing from the spirit f and scope thereof'as defined in the appended claims.

lln the drawing, Figure 1 is a sideelevation 25 of a rotary snap switch constructed in accordance with my invention; Fig. 2 is a vertical sectional view, on the line 2-2 of Fig. 3;

Fig. Sis a top plan view of the switch; Fig. 4l is a horizontal sectional view thereof on the line 4--4 of Fig. 2; l Fig. 5 is a vertical sectional view, on the line 5 5 of Fig. 3, certain parts being brokenk away for purposes of illustration;

Fig. 6 illustrates, in top plan and side elevation, one of the combined contact and terminal members; and

Fig. 7 illustrates, in top plan and side elevation, a modified forni vof fastening screw for the operating knob or handle.

Referring to the drawing, the numeral 10 designates a base member formed of insulating material, preferably porcelain. Base 10 is provided with a relatively large circular det5 pression or recess 11, and a concentric circular recess 12 which is relatively smaller and deeper. The bottom surface of recess 11 is therefore annular in outline, and said surface is divided into four angular segments 13, 14, 15 and 16 of equal size. The surface of each dll till

10, 1926. Serial N0. 87,243.

of said segments slants upwardly and in a clockwise direction whereby a circular ratchet is provided. Superimposed upon each of the diametrically opposite segments 14.- anol 16 is an angularly extending contact 17 having a terminal portion 18 integrally connected thereto as by means of the neck portion 19. Terminal 18 is bent, as best shown in Fig. 6, to provide an upper Hat portion 18a and a lower iiat portion 18b whereby the intermediate portion 18c is adapted to lie in the same plane as the neck portion 19 and contact 17. Base member 10 is provided at opposite ends with recesses 20 and 21 the surfaces of which are formed in a manner to permit the terminals 18 and neck portions 19 to fit snugly thereagainst. Moreover, the terminals 18 are provided with bent ends 22 and' 23 which extend upwardly to a point substantially iiush with the top surface of base 10. The end portion 28 is provided with a lateral notch 24 to facilitate soldering of the circuit wire to the terminal, as hereinafter described; whereassaid terminal is also` provided with an upstanding lug 25 for a like purpose. The recesses 20 and 21 extend outwardly, as shown at 26 and 27, to accommodate the circuit wires.

rlhe inner circular de ression 12 is adapted to receive the lower end of a rotatable shaft 28, said shaft being provided with an upwardly extending recess 29 adapted to house a compression spring 30. Shaft 28 is diainetrically slotted, as indicated at 31, to receive a cylindrical rod or pin 32, of bronze or other suitable conductive material, said rod extending laterally of shaft 28 into engagement with the oppositely disposed contacts 17 or into engagement with segments 13 and 15, depending upon the degree of rotation of shaft 2.8. `As best shown in Fig. 2 the shaft 28 extends into the recess 12 a distance sufcient to prevent ejection of rod 32 from slot 31 by the action of spring 30. It will be understood, however,i that recess 12 merely provides clearance for the lower end of sha-ft 28 and does not act as a bearing for the latter. On the other hand, shaft 28 is'provided with a reduced portion 33 and the shoulder 34; thereof bears upwardly under the action of spring 3() against the outwardly spun annular flange of an externally screw-threaded bushing 36. Said flange 35 is also adapted to form a rigid connection between bushing manner well known in the art.

Cover plate 38 is provided with diagonally disposed tapped perforations, each adapted' to recelve the threaded end of a screw or bolt 39 extending through a registering passage 40 vin base 10, as shown in Fig. 2; said passages being provided with countersunk portions 41 to receive the heads of bolts 3 9. An insulating plate or sheet 42 is interposed between cover plate 38 and base 10, said insulating plate being provided with perforations to permit passage of bolts 39, whereas the same is also provided with an enlarged opening 43 to accommodate shaft 28.

The reduced portion 33 of shaft 28 is drilled and tapped as indicated at 44, and a knob 45 is placed thereon. Knob 45 is knurled, as indicated at 46, or otherwise formed to provide a finger grip for operating the switch; whereas said knob is likewise provided with an opening 47 to permit yfree passage of a screw 48 therethrough into engagement with the screw thread 44. Screw 48 is provided.with a round slotless head 49, and the arrangement is such that upon substantial tightening of screw 48 the head thereof binds the knob 45 against the reduced. portion 33 of the shaft, whereas upon clockwise rotation of knob 45 thelatter is clamped more tightly to said shaft to insure joint movement of said parts. On the other hand, screw 48 is readily loosened upon counter-clockwise rotation of knob 45, thus preventing an undue strain upon the switch parts under such conditions.,

In mounting the switch upon a canopy or the like, a relatively thin nut or washer 50 is threaded onto the bushing 36, whereupon the latter is projected outwardly through an opening of suitable size in the canopy, and the nut'51 screwed onto the bushing to clamp the assembled switch in position. As will be apparent, the nuts 50 and 51 may be placed in position without requiring removal of the knob 45 or any other switch parts. Similarly it will be obvious that part 50 need not be screw-threaded, whereas if desired the same may be omitted.

The finished article may include suitable len ths of lead wiresn52 the bared ends of eac bof the latter being engaged with the notch 24 and then bent around the lug 25 whereby the terminal 18 and the wire end are temporaril held together. A suitable amount of sol er 53 is then placed over the 'wire end (as shown in Figs. 2 and 4) and melted to provide a permanent mechanical and electrical connection between the wire and terminal. vThe tip iof the wire is then preferably clipped olf close to the portion 23 of the terminal. The combined contacts and terminals are then inserted in the correspondin recesses in base 10. Thereupon the operating shaft 28 with its bridging contact rod 32 is inserted and the insulating plate 42 and top plate 38 with its bushing 36 are placed thereover. The various elements are then secured in assembled relation by means of screws 39 as aforedescribed. In practice when base 10 is formed of porcelain the segments 13 and 15 are preferably glazed to reduce friction and wear upon the metallic rod 32.

With the parts in the relative positions illust-rated in Fig. 4, and assuming-connection of wires 52 in a suitable circuit, such circuit will be completed across stationary contacts 17 by means of the contact rod' 32, whereas upon a quarter turn of the operating knob 45 in a clockwise direction rod 32 will be caused to ride upwardly on the contacts 17 against the action of spring 30, and when the highest point in each ofthe contacts 17 is reached rod 32 will snap out of engagement therewith into engagement with the lowest point in each of the segments 13 and 15. The circuit will thus be broken with a snap action, whereas upon an additional quarter turn of knob 45 in the same direction rod 32 will ride upwardly on insulating segments 13 and 15 and drop downwardly with a snap action into engagement with the lowe'st point in each of the contacts 17, as shown in Fig. 4.

In Fig. 7 I have shown a screw 54 which may be substituted for the screw 48 as a means for securing knob 45 to the operating shaft.` Screw 54 is provided with a plate or lens 55 of glass or other transparent or translucent material, said plate being adapted to cover and protect a coating or body of luminous material, whereas said plate is secured in any suitable manner within a recess in the screw head 56.

What I claim and desire to secure by Letters Patent is: l

1. In an electric switch, the combination with an insulating base having a circular recess therein, a rotatable diametrically slotted shaft extending into said recess but spaced from the Walls thereof, a plurality of ratchet teeth formed in said base around said recess, stationary contacts extending throughout the length of each of a diametrically opposed pair of ratchet teeth, terminal members formed integrally with said 'contacts and adapted to seat incorresponding recesses insaid base, an insulating cover on said base adapted to engage said termina-l members to hold the same in fixed osition, a cylindrical metallic rod extending aterally through said shaft into overlapping en agement with said ratchet teeth, and a coiled spring carried by said shaft and engaging said rod to provide for movement o the latter into and out y upper surface thereof, a shaft having a longitudinal slot therein, said shaft being rotatable in one of said recesses but spaced from the walls thereof, a rigid conducting rod'eXtending through said shaft and reciprocable within said slot, a plurality of annularly arranged ratchet teeth formed on said base with which said rod is adapted to engage, metallic contacts covering the upper surfaces of one pair of diametrically opposedgfratchet teeth, terminals integrally connected with said contacts and recesses adapted to receive said terminals, said terminals having portions extending upwardly to the top surface of said base, a' top plate having a bushing against which a shoulder on said shaft is adapted to bear, means for securing said top plate to said base, and an insulating plate interposed between said top plate and said base, said insulatin plate being adapted to engage the upward y extending port-ions of said terminals to hold the latter in substan tially fixed position.

3. In an electric switch for concealed mounting, the combination with an insulating base having a plurality of recesses in the upper surface thereof, a shaft having a longitudinal slot therein, said shaft being rotatable in one ofsaid recesses but spaced vfrom the walls thereof,l a rigid conducting rod extending through said shaft and reciprocable within said slot, a plurality of annular-ly arranged ratchet teeth, formed on said base with which said rod is adapted to engage, metallic contacts covering theupper surfaces of'one pair of diametrically opposed ratchet teeth, terminals integrally connected with said contacts and recesses adapted t0 receive said terminals, said terminals having portions extending upwardly to the top surface of said base, a top plate having a bushing against which a shoulder o n said shaft is adapted to bear, means for securing said top plate tosaid base, an insulating plate interposed between said top plate and said base, said insulating plate being adapted to engage the upwardly extending portions of said terminals to hold the latter in substantiall)7 fixed position, an operating knob adapted to fit over the upper end of said shaft, and a smooth-headed screw extending through said knob into engagement with a threaded recess in said shaft to thereby clamp said knob and shaft together.

4. In an electric switch for concealed mounting, the combination with an insulating base,- a series of annularly arranged ratchet teeth formed on said base, stationary contact members covering the top of each of a plurality of said ratchet teeth, said base having a circular recess arranged concentrically withv respect to said ratchet teeth, a diametrically slotted shaft extending into said recess but' spaced from the walls thereof, a metallic rod reciprocable within said slot under the action of said ratchet teeth upon rotation of said shaft, a metallic top plate secured to said base, said top plate having a portion against which a shoulder on said shaft is adapted to bear, and a coiled spring interposed between said shaft and said rod to bias the latter into engagement with said ratchet teeth, said spring being also adapted.

to bias said shaft into engagement with said bearing portion.

5. In an electric snapswitch, the combination with an insulating base, of a one-piece stationary contact and terminal, said base having a recess to receive said terminal bodily and a seat for said contact to support the same in a fixed position, a top plate to cover said recess, and means for securing said top plate to said base, said terminal having spaced portions thereof extending flush with the upper surface of said base to be engaged by said top platefor clamping said terminal in position. 6. In a device of the character described, the combination with integrally connected contact and terminal members, of a plurality of upstanding lugs on said terminal member, one of said lugs having a lateral notch to receive a terminal Wire, and the other lug being engageable by said wire, whereby said wire may be interlocked with said lugs to facilitate soldering thereof.

7 In an electric snap switch, the combination with a switch contact, of a terminal member therefor, a plurality of upstanding lugs on said terminal member, certain of said lugs being arranged at substantially right angles to each other, one of said lugs having la lateral notch to receive a terminal wire and another of said lugs being frictionally engageable by said wire, whereby said wire may be interlocked with said lugs to support said terminal member during soldering of the wire thereto.

In witness whereof, I have hereunto subscribed my name.

`GEORGE J. MEIJER.

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