US2006954A - Electric switch - Google Patents

Description

July 2, 1935. c.4 w. KUHN 2,006,954

ELECTRIC SWITCH Filed July 3, 1933 5 Sheets-Sheet l- July 2, 1935. r; w, KUHN 2,006,954

ELECTRIC SWITCH Filed July 5, 1933 5 Sheets-Sheet 2 @M @m MKM @s XM/mg' C. W. KUHN ELECTRIC SWITCH July 2, 1935.

Filed July s, 1953 5 sheets-snaai 5 Patented July 2, 1935 2,006,954

UNITED STATES PATNT lFFECE ELECTRIC SWITCH Clarence W. Kuhn, Milwaukee, Wis., assignor to Cutler-Hammer, Inc., Milwaukee, Wis., a corporation of Delaware v Application July 3, i933, Serial No. 678,750

lo Claims. (Cl. Zilli-l2@ This invention relates to electric switches, Fig. e is a fragmentary vertical sectional View and more particularly Vto manually operated illustrating the operating mechanism in a posiswitches having automatic means associated tion for effecting resetting of the overload retherewith for releasing and throwing the switch sponsive mechanism;

5 to off position under overload conditions. Fig. 5 is a perspective view of the movable 5 An object of the invention is to provide an Contact element of the switch; improved manually operated switch having a Fig. 6 is a front elevational view of the switch trip free overload mechanism associated therewith the movable contact element removed; with, or in other words, a switch which is Fis` 7 iS a perspective View Of the Snel) Operate l0 tripped to open lposition in response to preing mechanism of the switch; 10 determined current conditions even though Athe Fig. 8 is a rear elevational View of the switch manual operating means is deliberately held with portions broken away and shown in secin on position. tion;

Another object is to provide an improved Fig. 9 is a front elevational view of an enclosswitch of the aforesaid character which opering Casing fOr the SWiiChJ" 15 ates with a snap action when actuated either Figs. l0 and ll are sectional views on lines manually or automatically and which is reset i-i@ and ii-ii, respectively, 0f Figs. 9; by return of the manual operating means to Fig. 12 iS a fragmentary betteln View O the olf position. enclosing casing;

2o Another object is to provide a switch of the Fis. 13 is a front elevational view of a no 20 aforesaid character having improved overload voltage release mechanism for the switch shown tripping means associated therewith including in Fig. l, and overload responsive elements of the self-solder- Fig. 14 is a side elevational view of the no ing type. voltage release mechanism shown in Fig. 13

2,5 Another object is to provide c, Switch of the with portions of the switch shown in section. aforesaid character having improved no voltage Referring to the drawings, the same illustrate protective means associated therewith. a starter for multi-phase alternating current Another object is to provide an improved` motors including an insulating base i having enclosing casing for switches of the aforesaid a snap switch mechanism 2 mounted thereon go character having means associated therewith which is provided with contacts for connecting for indicating tripping of the switch under overline terminal devices L1, L2, L3- mounted upon load conditions. the upper end of said base to load terminal de- Another object is to simplify and generally vices T1, T2, T3, respectively, mounted upon the improve the construction of switches of the lower end of said base. As hereinafter set forth,

above mentioned type and to provide a conswitch mechanism 2 is of the free tripping type, 35

struction in which practically all of the parts and base l carries a pair of electro-thermal may be cheaply made of molded material and overload devices 3 and l, each of which is resheet metal stampings. sponsive upon predetermined overload condi- Various other objects and advantages of the tions in one of the load circuits to effect tripping Ll() invention will hereinafter appear. of said switch mechanism.

The accompanying drawings illustrate an em- The switch mechanism 2 includes a movable locdiment of the invention which will now be contact carrier 5 formed of insulating material described, it being understood that the emhodiand having openings adjacent opposite ends ment illustrated is susceptible of modicaticn thereof for receiving a pair of guide pins 6-6 la without departing from the spirit and scope of mounted upon the front face of insulating 1oase 45 the appended claims. i and projecting forwardly therefrom. Said In the drawings, contact carrier is biased outwardly by coil Figure l is a front elevational View of a switch springs l-'i which surround the guide pins @-51 embodying the invention; and said guide pins are provided with heads on al) Fig. 2 is a vertical sectional view taken sub.- the outer ends thereof which act as stops to 50 stantially on line 2 2 of Fig. l and illustrating limit outward movement of said carrier when the the switch in open position; same is moved into the open position shown in Fig. 3 is va sectional view similar to that shown Fig. 2. Contact carrier ti is movable between the in Fig. 2, illustrating the switch in lclosed posiopen position shown in Fig. 2 and a closed position; 'tion shown in Zi hy a snap operating mechanism 3 including an actuating lever l@ and a cooperating spring pressed actuated member II.

Actuating member I comprises a sheet metal stamping which is rotatably mounted upon a pin l2 carried by a bracket |13 fixed to the rear face of base i. As shown in Fig. 7, said actuating member is formed to provide spaced parallel.

side arms each having a leg I5 projecting downwardly from pivot pin I2, and a leg l5 projecting forwardly from said pin. As shown in Figs. 2 and 3, the legs l5 extend through an opening Il in base l and are connected at their outer ends by a portion l@ to which an operating handle I9 is secured by a screw 2B. The legs l5 are located within a recess 2l in the rear face of base I, and each o f said legs has its lower end shaped to pro-'- vide a cam surface having a crest 22 and inclined faces 23 and 24 on opposite sides thereof. I

The actuated member II is arranged within an opening 25 in base l (Figs. 2 and 3) and has a pin 28 fixed thereto adjacent the inner end thereof which carries a pair of rollers 29-29 arranged to ride upon the cam surfaces on the lower ends of the legs I5. A spring 3| having one end connected to actuated member I l and its opposite end connected to pin i2 serves 'to yieldingly hold the rollers 29--29 in engagement with -said cam surfaces, and as shown in Figs. 2 and 3 said spring is connected to said actuated member Il at a point to the left of said rollers to thereby bias the outer end of said actuated member upwardly. The outer end of actuated member II is located within a centrally arranged opening in contact carrier 5 and the upper edge thereof is provided with a slot 32 for receiving a latch plate 33 secured tothe rear face of contact carrier 5 by rivets 3G.

The bracket f3 is provided with a vertically arranged body portion 35 having its upper end bracket I3 to limit movement of said actuating member in opposite directions. The securing secure an angle plate 43 to a forwardly extending projection 44 on the front face of insulating base I, said plate being also secured to said base by a screw 45.' Asis apparent from Fig. 3, plate 43 cooperates with plate 33 on contact carrier 5 to limit inward movement of said contact carrier and as shown in Figs. 4 and 6 said plate is provided with an inwardly extending portion 46 having. a 'slot 41 therein for receiving the actuated member II to guide the latter.

The operation of the aforedescribed operating mechanism will now be described.' Assuming that the aforedescribed parts are in the position shown in Fig. 2, upward movement of the operating handle I9 causes the cam surfaces on the lower, ends of legs I5 of actuating member I0 accepts carrier 5 from the open position shown in Fig. 2 into the closed position shown in Fig. 3. It will be noted that when the operating handle i9 is in the position shown in Fig. 3 the rollers 29 engage surfaces 268 of increased angularity upon the inner ends of cam surfaces 24 to therebyincrease the holding force on contact carrier 5 when the same is moved into closed position. Upon return movement of the operating handle I9 from the position shown in Fig. 3 into the position shown in Fig. 2 the cam surfaces on the lower ends of legs l5 of actuating member lll move inwardly with respect to the rollers 29. During final movement of operating handle I9 into the position shown in Fig. 2 the crests' 22 of the cam surfaces assume a position to the right of the'aXes of' rollers 29 and spring 3l then causes said rollers to move outwardly over the cam surfaces23 to effect snap movement of actuated memberv Ill and contact carrier 5 from the closed position shown in Fig. 3 into the open position shown in Fig. 2.

As will now be set forth, when contact carrier 5 is moved into the closed position shown in Fig. 3 the aforementioned overload devices 3 and il are responsive upon given overload conditions in the circuits connected to terminal devices 'I'l and T2 to rmove actuating member II out of engagement with plate 33 and thereby permit said contact carrier to move to open position. Also as will now be set forth, the operating handle I9 is returnable from the positionshown in Fig. 3 into the position shown in Fig. 2 to effect resetting of either or both of the overload responsive devices 3 and i and to also relatch actuating member II with plate 33 on contact carrier 5. f

Each of the overload devices 3 and l includes a vertically arranged tripping member 50 slidably mounted upon the rear face of base l and having an overload responsive element 5I of the self-soldering type associated therewith for normally holding the same Yin a retracted position shown in Fig. 8 against the action of a spring 52.`

The self-soldering elements 5I are arranged in spaced relation adjacent the lower end of base I and their associated tripping members 50 are arranged in opposed relation therebetween. Each of the self-soldering elements 5I includes a heater 53 of helicall form, arranged within a recess 54 in the front face of base I, a tubular member 55 surrounded by said heater and fixed within an opening in said base, and a pin 56 located within said tubular member and normally held against rotation with respect thereto by a solder connection; Each of the pins 56 has an enlarged toothed head 51 on the inner end thereof to be engaged by a spring latch 58 fixed to the lower end of its associated tripping member 50. As shown in Fig. 8 the tripping members 50 are slidably mounted between oppositely disposed L-shaped projections 60-60 on the rear face of base I and the same are held in position upon said base byV an insulating plate 6I having its lower end secured to said base by a screw 62 and having its upper end supported by the bracket I3. The springs 52 associated with the tripping members 50 are held under compression between projections on the upper ends of said members and the lower legs of procooperate with a, trigger 64 associated with the actuated member II. Said trigger is arranged below the actuated member `II and has a tongue Aen accepteon the inner end thereof to be engaged by either of the tripping members t and has its outer end provided with spaced side arms tt-tt which are pivotally mounted upon a pin il xed to said actuated member adjacent the slot Y .as is apparent from the foregoing, the selfsolclering overload elements 5i serve to normally hold the tripping members 50 in the positions shown in Fig. 8. However, upon closure of the switch each of the elements 5i is responsive upon given overload conditions to release its associated tripping member 5B and thereby permit upward movement thereof under the action of its associated spring 52. Upon upward movement of either or both of the tripping members 5t the inner end of trigger 64 is moved upwardly land the side arms ES of said trigger, by engagement with the inwardly extending portion it of plate t3, effect downward movement of the outer end of actuated member il. The slot 32 in the actuated member il is thus moved out of engagement with latch plate S3 and contact carrier 5 is then moved forwardly into open position with a snap action by its associated springs l.

It will be noted from Figs. 3 and 7 that the actuated member il has an upwardly extending toe projection t3 on the inner end thereof. Upon tripping of the switch the rollers '29 are moved slightly inwardly with respect to the cam surfaces 2da from the position shown in Fig. 3 under the action ci spring 3i and actuated member ii then assumes a position wherein its toe projection engages a shoulder @E formed by the offset portion Si on the lower end ci bracket With the actuated m'em er ii in this position downward movement oi the operating handle iii from the position shown in Fig. 3 causes said actuated member to move downwardly into a position shown in 4 just prior to movement o said operating handle into the position shown in Fig. 2. As is apparent, during movement of the actuated member li into the moves downwardly therewith to return either or both of the tripping members from its tripped position into normal position. Upon return ci the handle into the position shown in Fig. 2 the crests of the cam surfaces are moved to the right of the axes o rollers and said rollers then move outwardly over the cam surfaces to effect latching or" actuated member l with plate on contact carrier In connection with the foregoing it should be noted that during the aforedescribed resetting operation the toe projection on actuated member ii is held in engagement with shoulder 69 on bracket i3 and the outer end or said actuated member is thus biased downwardly into engagement with a surface l@ on plate 33 as shown in Fig. e. With the actuated member ill held in this position during resetting operations the tripping members are reset in such positions as to prevent the upper ends thereof from obstructing inward and outward movements of said actuating member and its associated trigger @d during manual operations of the switch.

As hereinbeiore stated the above described switch mechanism is provided with contacts 'for connecting line terminal devices .L1-L2 and L3 mounted upon the upper end of base i to load terminal devices 'T1-T2 and T3, respectively, mounted upon the lower end of said base. As shown in Fig. 5, contact devices l2, it and ld are mounted upon the rear face oi contact carable therein against the action of a rier E, the Contact devices 'i2 and i3 beingarranged in spaced relation adjacent the upper edge of said carrier, and the contact device lll being arranged midway between the former contacts and adjacent the lower edge of said carrier. Each of said Contact devices includes a U- shaped holder 'i5 and a U-shaped bridging contact 'it mounted within said holder and movspring l'i. Each of the contacts it is held in assembled relation within its associated holder i5 by inturned end portions i8 on the latter, and as is apparent from Fig. 5 said contacts may be tilted with respect to their associated holders to permit removal thereof. Base l is provided with openings for receiving each of the contact devices "i2, 'i3 and and each of said devices cooperates with a pair or" spaced stationary contacts mounted within recesses formed in the rear face of said base.

As shown in Figs. 6 and 8, the heater 53 of overload device Si is connected between terminal device T1 and a binding post il@ and Contact device 62 cooperates with a pair of stationary contacts i2@- and lh, the former being connected to terminal device L1, and the latter being connected to binding post d@ by a connection Si. The heater 53 of overload device is connected between terminal device T2 and a binding post 32, and contact device 'i3 cooperates with a pair or stationary contacts its and i311, the former being connected to terminal device L2 and the latter being connected to binding posty by a connection Contact device fl cooperates with stationary contacts Eil@ and lili), he iol-mer being connected a connection and the latter being connected to terminal device T3 by a connection As shown i gs. 9 and is the aioredescribed switch is provided with boit-shaped enclosing casing provided wth a cover Base i of the switch is secured to the rear wall or the enclosing casing by securirur screws which pass through corner openings in said base and an insulating plate S9 is in`erposed between said wall and the rear face of said base. The cover is hinged to the upper wall oi casing Si', as shown at 9S, and the face of said cover is provided with an opening for receiving the operating handle i@ oi the switch. A vertically arranged ioclring bar 9i having an opening therein for receivin7 the operating handle is mounted upon the rear face of cover Said bar is supported by brackets S2 secured to the rear face of said cover, 'and the low-er wall of casing 8l is provided with an opening 93 for receiving a projecting portion on the iower end of said bar. As shown in Fig. l2, the opening 93 is shaped to provide oppositely disposed inwardly extending locking projections @il-@fl for engaging the outer face oi locking bar di and as shown in 9 said inciting bar is provided with recesses on opposite sides thereof for receiving the locking projection When the switch is in closed position, as shown in Fig. 9, the locking projections Sill on casing engage the outer race oi locking bar to prevent opening of the cover. However, when the operating handle i@ is moved downwardly into open position the locking bar 9i moves therewith into a position wherein its recesses are aligned with the locking projections @Il and the cover 88 can.. then be swung outwardly into open position.

The cover of the enclosing casing is provided with a mechanism operable by the contact carrier 5 to indicate opening and closure of the switch. A- small window 97 is provided in a plate 98 fixed to the front face of cover 88 and through this window a slider 99 bearing legends on and off is visible. The slider 99 is slidably mounted between plate 98- and locking bar 9| within an opening in cover 88 and is biased upwardly byA a spring |06. A button IUI is secured to the inner face of slider` 99 and the outer face of contact carrier 5 is provided with a projection having an inclined face |02 for engaging said button. When contact carrier 5 moves into oi position the facel |02 engages the button ||Il| to move slider 99 downwardly into a position wherein the off legend thereon shows within the window 9i. Upon movement of contact carrier 5 into on position face |62 moves out of engagement with button |Q| and slider 99 is then moved upwardly by its associated 4spring .|90 into a position wherein the on legend thereon shows within the window 9|.

The enclosing casing 8l and its cover 88 are provided with lock projections |86 and |05, re-

spectively, which are arranged on opposite sides of the locking bar 9|. Said locking bar has its lower end provided with a slot |96 and an opening |0`| and said lock projections are provided with padlock openings |98 in verticalalignment with slot |06 and padlock openings |09V in vertical alignment with the opening |01. With the switch in. on position the lower end of locking bar 9| is located immediately above the openings |09 in the lock projections, and when a padlock is inserted in said openings the switch is locked in on position. Upon opening of the switch the opening in locking bar 9|' is aligned with the openings |09' in the lock projections and when the padlock is inserted in said openings the switchislocked in open position. Upon insertion of-the padlock 'in openings |08 cover 88 is locked to the enclosing casing 81 and the lockingbar 9| is released to permit closure or openingof the switch.

Referring now to Figs. 13 and 14, the same illustrate a no-voltage release mechanism for the aforedescribed switch. The actuating member I0 of the switch is biased towards open position by a spring and is adapted to be held in closed position by a pair of no voltage release magnets ||2 and I|3 each to be connected in one of `the circuits controlled by the switch. Said magnets are mounted upon a plate H4 secured to the rear fac of insulating base and the spring is held under compression between a forwardly extending bracket |I5 fixed to said plate and a block ||6 pivotally mounted upon a pin ||1 carried by the forwardly projecting legs |6 of actuating member |0. An operating lever ||8 is pivotally secured to the forwardly projecting legs |6 of actuating member by a pin 'H9 and said operating lever is provided with'orwardly projecting arms |20 and upwardly projecting arms |2|. An operating handle |22 .is secured to the .outer ends of arms |20 and the upper ends of arms |2| have an armature member, |23 mounted thereon to be attracted by the magnets ||2 and H3. The arms |2| also carry ,a pin |2l having a roller |25 mounted thereonwhich cooperates with a downwardly extending projection |26 on the front end of bracket H5.

When the operating handle |22 is pressed upwardly from the position shown in Fig. 14, lever m is held against clockwise rotation by engagement of roller |25with the projection |26 on bracket ||5. Lever ||8 is thus movedupwardly and the actuating member l0 moves therewith to eiect closure of the switch. Upon closure of the switch roller |25 moves over the upper end of projection |26, as shown in dotted lines in Fig. 14, and the armature member |23 is then attracted by the electromagnets ||2 and ||3 to hold the switch in closed position against the action of spring When the operating handle |22 is released spring I tends to move the roller |25 outwardly over the upper end of projection |26, but the upper end of said projection is soshaped that a relatively slight holding force on the armature member |23 serves to maintain the switch in closed. position against the action of spring I. Under no volt- `age conditions the armature member |23 is re- YLetters Patent is:

l. A switch device having a movable contact element biased towards open position, a manual operating member reciprocable to move said contact element between open and closed positions, snap operating mechanism interposed between said operating member and said contact elementto move said contact element into and out of open or closed position with a snap action,

said mechanism including a latching part adapted to be tripped to disconnect said contact element from said manual operating member, and an overload mechanism responsive to trip said latching part, said latching part and said overload mechanism being resettable by said manual operating member.

2,. A switch device having a movable contact element biased towards open position, a manual operating 'member reciprocable to move said contact element ,between open and closed positions, snap operating mechanism interposed between said operating member and said contact element to movesaid contact element with a snap action, said mechanism including a latching part adapted to be tripped to disconnect said contact element from said operating member, and an overload mechanism responsive to trip said latching part, said overload mechanism including a self-soldering overload responsive element, and a spring biased tripping part normally held in a given position by said overload element and movable upon response of said overload element to trip said latching` part, said latching part and said tripping part being resettable by said manual operating member..

3. A switch device having a movable contact element biased towards open position, a manual operating member reciprocable to move said contact element between. open and closed positions, snap operating mechanism interposed between said operating `member and said contact element for moving said contact element ating to reset said overload mechanism and #to connect said actuated element.

4. A switch device having a movable contact element biased towards open position, a manual operating member having a cam associated therewith, an actuated part releasably connected to said contact element and yieldingly held in engagement with said cam, said operating part being movable with a snap action by said cam upon reciprocating movements of said opermeniber, an overload mechanism responsive to release said actuated part from said Contact element, said operating member when moved into a position to edect opening of-said switch providing ior resetting oi said overload mechanism and for reconnection oi said actuated part to said contact element.

5. in an electric switch, in combination, a reciprocable contact element biased towards open position, operating means therefore including a pivoted operating part and a releasable operating connection between said operating part and sai-d contact element adapted to be tripped to iree said contact element 'from restraint by said operating part, and an electro-thermally controlled device of the solder type having a spring biased part releasable automatically under given electrical conditions to trip said operating connection, and means associated with said operating means for resetting said spring biased part upon release thereof and for also eifecting resetting ofsaid operating connection.

6.111 an electric switch, in combination, a reciprocable contact element biased towards open position, operating means therefor including a manual operating part and a latch connection between said operating part and said repart to said contact contact element adaptedto be tripped to free said contact element from restraint by said operating part, and an 'electro-thermally controlled device of the solder type having a spring biased part releasable automatically under given electrical conditions to trip said latch. and means associated with said operating means for resetting said spring biased part upon release thereof. l

7. In an electric switch, in combination, a reciprocablecontact element biased towards open position, operating means therefore including a manual operating part and an operating connection between said operating part and said Icontact element including a latch adapted to be tripped to free said contact element from restraint by said operating part, and an electro-thermally controlled devicec of the solder type having a spring biased part releasable automatically under given electrical conditions to trip said latch, said operating part when moved to a position to eifect opening of said contact element being adapted to reset said latch and said spring biased part.

8. In an electric switch, in combination, an insulating base having a pair of stationary contacts mounted upon the front face thereof, a movable contact element mounted upon said base for bridging said stationary contacts, said contact element having spring means associated therewith for moving the saine away from said stationary contacts, operating means for said movable contact element including pivoted operating part and a releasable operating connection between said operating part and said contact element adapted to Toe tripped to iree said contact element from restraint by said operating part, an electro=tiierinally controlled device oi the solder type having a spring biased tripping part mounted upon the rear face of said base and releasable automatically under given electrical conditions to trip said operating connection, and means associated with said operating means for resetting said spring biased part upon release thereof and ior also effecting resetting oi said operating connection.

9. L'n an electric switch, in combination, an insulating pase having a plurality of pairs or" stationary contacts mounted upon 'the iront face thereof, a movable insulating yolie mounted upon said base and having a plurality of bridging contacts associated therewith for engaging each of said pairs of stationary contacts, spring means associated with said yolte for biasing the saine and the bridging contacts carried thereby away from said stationary contacts, operating means for said yoke including a manual operating part and a releasable operating connection between said operating part and said yoke adapted to be tripped to free said'yoke from restraint by said operating part, a plurality oi electrotherrnally controlled devices of the solder type mounted upon said base, each of said devices including a heater connected to certain oi said stationary contacts and a spring biased tripping part releasable automatically under given electrical conditions in said heater to trip said operating connection, and means associated with said operating means for resetting any or all of said spring biased tripping parts upon release thereof and for also effecting resetting oi said operating connection.

10. In an electric switch, in combination, a plurality of pairs of insulated stationary contacts, a reciprocable insulating yoke having a plurality of bridging contacts yieldingly mounted thereon for engaging each of said pairs of stationary contacts, said yoke being biased to disengage said bridging contacts from said stationary contacts, operating means for said yoke including a manual operating part and a latch connection between said operating part and said yoke adapted to `be tripped to free said yoke yfrom restraint by said operating part, a plurality of electrothermally controlled devices of the solder type. each of said devices including a. heater connected to certain of said stationary contacts and a spring biased tripping part releasable automatically under given electrical conditions in said heater to trip said latch, said operating part when moved to a position to disengage said bridging contact from said stationary contacts being adapted to eifect resetting of said latch and any or all of said tripping parts.

CLARENCE W. KUHN.

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