US1872122A - Electric switch - Google Patents

Description

Aug. 16, 1932 J. R. COOK ELECTRIC SWITCH Original Filed Deo. 4. 1922 2 Sheets-Sheet l 35 5l zz 3@ l Z0 .l Z z3 l K5 7 /5 j. l0 /4 A ug. 16, 1932. J. R. cooK 1,372,122

l y ELECTRIC SWITCH -Orginal FiledkDeo. 4. 1922 2 Sheets-Sheet 2 Ten-far fymww C Patented Aug. 16, y1932 UNITED STATES PATENT OFFICE l W J' OEL B.. COOK, 0l' CLEVELAND, OHIO, ASBIGNOB, BY HEBNE ASSIGNMENTS, TO WESTING- HOUSE ELECTRIC & IANUFACTUBING COMPANY, A CORPORATION 0F PENN- 'SYLVANIL morale swrrcn Application led December 4, 1982, Serial No. 604,762. Renewed January 31, v1930.

This invention relates to circuit breakers and is particularly concerned with that ty e wherein an electro-responsive tripping evice may release a circuit closer responsive to changes in the value of the current, andin- K cludes manual means for resettingthe tripping device and closing the circuit. A convement and frequent use of the invention is in connection with a manually operated circuit closer, normally governing the circuit to open and close the same, as desired,

e but allowing the circuit breaker to act un- N and circuit breaker in series.

I consider it advantageous to so connect the circuit breaker and switch mechanism;

that the operation of the switch may close 4the circuit breaker, and resetthe latch after Vit has been opened, and thereafter allow the Vmanually operated switch to govern the circuit through an indefinite number of makes and breaks, causing opening and closing of the circuit until an abnormal condition occurs. Such a general arrangement is illustrated in my copendingl application filed Sept.,18, 1922, Serial No. 588,755.A

' An object of this invention is to provide a simple and effective arrangement of the operating connectionbetween switch operating mechanism and the electroresponsive ciricuitv closer. Further objects include compactness of the elements comprising the circuit closer,\cheapness of manufacture, certainty of operation, while having no parts subject to-excess Wear or'likely to get out of order. p

In the drawings, I have shqown an arrangement of a rotary snap switch of well known carrying current and adapted upon an overload to render active a shunt through the solenoid, thereby tripping the circuit breaker, and I have so connected the snap switch member with the circuit breaker elements that subsequent turning may reset the snap switch.

One of the objects of the present invention is to provide a simple arrangement of latching mechanism whereby if the abnormal circuit condition, that is for example, the overload still'exists, the circuit brea er can not be reset until the current is normal. Another specific object is to so arrange the circuit connections through vthe solenoid with relation to thefcircuit 'breaker that the current through ythe circuit breaker is never more than momentary,` that is, it can not pass through the solenoid longer than a period just sufficient to cause it t operate to open the circuit breaker. This vallows the use of a small, and therefore cheap, solenoid having light windings.

In the drawings, Fi 1 is in the nature of a side elevation of t e manually operated snap switch and electrofresponsive switch mounted on the same base, the housing for each being shown in section;'Fig. 2 is a substantially axial section through the rotary snap switch and corresponding parts of` the electroresponsive circuit brea er; Fig. 3 is a sectional detail showing the arrangement of the solenoid actuating the trippin mechanism; Fig. 4 is a sectional lan of t e electro-responsivev vcircuit brea er mechanism showing its housing in section; Fig. 5 is a similar view showing the parts 4ofthe circuit Ybreaker in open circuit position; Fig. 6 is a -sectionaljplan of the snap switch showing its housing in section; Fig.l 7 1s a sectlonal plan showing the step by step mechanism ofv the snap swltch; Fig. 8 is a sectional detail taken substantially on the line 8-8 of Fig.

4, showing thethermostatic electric conduc tor in its closed position; Fig. 9 is a similar view showing the open position thereof; On

design, associated with the circuit breaker, Fig. 4 is shown a broken line indicating the construction governed by latch mechanism plane of the section of Fig.l 2; the plane of controlled by a solenoid in turn, controlled the section'through the solenoid is indicated byL a current responsive member,- normally by the line 3--3 of Fig. 4. I

' 10 embraced by the spring 11, engaging one Y A suitable base for the mounting of the parts consists of a block 1, preferably rigid with a plate 2, somewhat larger in diameter, while the block 1 forms a bearing for the shaft 5 having the usual hand knob 3 for a snap switch as shown. As is customary in switches of this type, the shaft 5 is provided with a projection or cam G allowing a relative movement, and a rotatable stopwasher 7 adapted to engage projections 8 on a plate 9. This is shown particularly in Fig. 7, these parts appearing in section in Fig. 2. On this shaft 5 is provided the usual sleeve of the notches in the fiange 12, while the other end engages the carrier 13 for the switch blades 14, adapted in one position to bridge between contacts 15 and 16, and in another position, brought about by a quarter turn of the knob, to stand away from the contacts, that is, at right angles to the position in Fig. 6. The shaft 5 is shown as projecting through the block 1 and plate 2 and as carrying rigidly on its end a two part cam 20, adapted to engagea projection 21 formed rigid on a circuit breaker blade 22, shown as pivoted at 23 and adapted in one position, as shown in Fig. 4, to engage a contact 25.V

In order to make clear the function of the severai parts, the path of the current may be traced through both switches as follows: The current may pass, say from one of the lead wires 26 to the terminal 15 as shown in Fig. 2 and thence through the switch blades 14 to the terminal 16, through a wire 28 to the pivot 23, then through thepivoted blade 22, Contact 25, and thence through a thermostatic bar designated 30, to a contact strip 32; and thence to the other lead wire 26.

The thermostatic bar preferably is made up of two strips ofmetal secured together and adapted when carrying an excessive current to become heated consequent upon the resistance offered, the heat causing the barvwhich is rigid at one end, as shown in Figs. 8 and 9, to raise its contact from the member 32, thus interrupting the lnormal flow of the current, by opening the normal circuit. rihis shunts the current as will now be described, through a solenoid governing a latch for the switch blade 22.4

The circuit breaker blade 22 is urged to open by any 'suitable yielding means such as a spring 35, shown as attached at one end to the blade and at the other to a pin or post, or the like 36 which may be rigid. with the plate 2. In the position shown in Fig. 4, this blade is held in en agement With the contact 25 by a latch mem er consisting of a bar 40, pivoted at 41 and having a projecting shoulder adapted to engage the end of the blade or bar 22. The'end of the bar 40 embraces a reduced portion of a pin 45 attached to the solenoid core as shown particularly in Fig. 3. This reduced portion pro- `vides a. shoulder on the core pin at either side of the bar 40.

The solenoid may comprise the usual coils indicated at 46 in the form of a spool mounted upon supports 48 carried on the plate 2, the core being surrounded by a sleeve 49 in which the solenoid may slide. rl`he core pin 45 is preferably of nonmagnetic material while the core 50 is of suitable iron. The pin forms a reduced extension projecting through an opening in one end of the support, thus providing a space for a spring 52, normally urging the core to the right. The coil is shown as connected in parallel with the thermostatic bar 30 by wires designated leading to the contacts 25 and 32 so that when the thermostatic bar is electrical-` ly disconnected the solenoid forms a shunt, bridging this break in the circuit with the result that the heavy portion of the core 50 tends to center itself within the core 4G. The first part of the movement being idle until the inner shoulder engages the bar 40 after Athe core has attained some momentum, whereby the bar 40 is forcibly and certainly disengaged from the circ-uit breaker blade 22. The thermostatic bar 30 is of such proportions that, when it is closed, the major portion of the current through the circuit-breaker-switch blade 22 passes through the thermostatic bar, and very little current passes through the solenoid 4G. However', when the thermostatic bar, which shunts the solenoid 4G,

moves out of engagement with the contact 32, all of the current through the circuit breaker passes through the solenoid coil and causes it to trip the circuit breaker to open position.

Since the solenoid coil is carrying all of the current passing through the blade 22 at the time the circuit therethrough is beingv interrupted. the solenoid serves as a choke coil and limits the current to a predetermined value, thus preventing an excessive current under overload or short-circuit conditions that would be destructive to the circuitbreaker-switch blade 22 and the contact 25.

If now the switch handle 3 be operated, the

first quarter turn will simply open the snap switch, the next quarter turn will cause one AAJ the circuit, the latch controlled circuit breaker may be readily manually set by simply llO . these casings ma the circuit breaker blade 22, throughout an indefinite number of makes and breaks of .has the usual casing designated 60 while the latch controlled circuit breaker onthe other side of the base may be covered by a suitable casing G2. Convenient means of securing consist of a plurality of ears 63, registeringwith bosses 64 of the plate 2 provided with openings to receive suitable bolts or like securing devices. l

I am aware of various maximum current load automatic cutout devices combined with service switch constructions and particularly the disclosures of the patent to Perkins #287,321 of October 23, 1883, and the disclosure of an automatic opening and closing device having a magnetically actuated detent i in the Drake Patent `:;#569,960 of October My present effort has been to co-ordinate the mechanisms of a. magnetically controlled circuit breaker and a snap switch of modern construction in compact manner whereby the snap switch may be operable in the usual manner and the operating means therefor may function only to close the circuit breaker without influencing the functioning of the current breaker opening means in the event lof a prevailing overload condition in the circuit controlled by the device'. A

I claim f 1. An electric circuit controlling device.

lcomprising separable contacts.y means for .closing the contacts, latching mechanism for holding the contacts closed, a solenoidv and core for releasing said latch, a manually operable rotary member for actuating the closing means, a separate switch actuated by said manually operable member through successive makes and breaks. independently ofI said contacts and a. normally closed bimetallic thermostatic switch connected in series with said first named contacts and the contacts of the last named switch.

2. An electric circuit controlling comprising a circuit breaker tending to open, a. latch for holding it closed, a solenoid connected withl the latch, a manually operated switch,fmeans for connecting it to the circuit breaker, whereby movement of said y switch may close the circuit breaker and becomedisconnected while the'circuit breaker remains closed, electric connections through the solenoid whereby it may be responsive to abnormal circuit conditions to release the device latch and a normally closed bimetallic thermostatic switch connected in series withv the contacts of the circuit breaker and switch and bridging the connections of the solenoid.

, 3. The combination with a circuit breaker,

of yielding means tending to open it, a. `latch for holding it closed, an electro-responsive control device for releasing the latch, a manually operated switch having mechanicalmeans for closing the circuit breaker and placing it under the control of the latch, electrical connections through lthe circuit breaker and manually operated switch for connecting the contacts thereof in series, a normally closed bimetallic thermo-responsive bar normally carrying the current and adapted to open the circuit under abnormal conditions, and thereby cause the full current of the circuit to pass through the control device. 4. The combination with a circuit breaker, of yielding means tending to open it, a latch for holding it closed, an electro-responsive control device for releasing the latch, a manually operated switch having mechanical means-for closing thecircuitbreaker and placing it u nder the control of the latch, electrical connections through the circuit breaker and manuallv operated switch for connecting the contacts thereof in series, a bimetallic thermo-responsive bar normally carrying the current and adapted to open the circuit under abnormal circuit conditions, and shunt i connections around said bar through thecontrol device to render it'active momentarily when said bar is in open position.

-5. The combination with a circuit breaker,

-an electro-responsive means causing it to open 6, The combination with a circuit breaker,

an electro-responsive means causing it to opened and a. manually operated switch 1nv series, with the circuit breaker and adapted to be temporarily mechanically lccuinected to the circuit breakerfor closing it and to be disconnected therefrom during the normal 1 operationof the switch, said electro-responsive means including a bimetallic thermo-v resistance bar adapted to normally carry the drrent but to open the circuit under abnormal conditions, and a magnetic solenoid having'electric connections shunting around the bar.

7. In a device of the character described, the combination of a hand operated revolving snap switch, a circuit breaker switch in series therewith and adapted to be closed by a revolving movement of a manually operated member of the snap switch and having electro-responsive means for opening it automatically, and a normally closed self-closing circuit breaker governing the circuitand responsive to overload to open the circuit and thereby cause the electro-responsive means to open the circuit breaker.

8. An electric circuit controlling device comprising manually separable contacts and other automatically separable contacts, a manually operable member for closing both sets of contacts, means connecting all of said ing normally contacts in series, a latching mechanism for holding the automatically separable contacts closed, a magnetic device for tripping the latching meclmnism, said magnetic device beelectrically -connected in multiple relative to the means connecting the contacts in series, and a thermostatic switch connected in series with said contacts, bridging the connections for the magnetic device,

whereby the highly magnetic device will be in series with the contacts when the thermostatically operated switch is open.

9. In a device of the character described, the combinataion of a base member, a snap switch mechanism supported on one .side

thereof, a circuit breaking device mounted on the opposite side of the base member, an operating member extending throughfthe base, and means mounted on the operating member for closing and opening the snap switch and for closing the circuit breaker.

10. In a device of the character described, the combination of a snap switch mechanism,

- a base formed of insulating material supporting the snap switch mechanism on one side thereof, a separable pair of contacts comprising a circuit breaker mounted on the opposite side of the base and in series with the switch mechanism, an operatingtmember extending through the base, means mounted on the operating member for actuating the snap switch mechanism for closing the contacts 'of the circuit breaker, a latch mechanism mounted on the base adjacent the separable conbreaking. device mounted on the opposite side tacts of the circuit breaker for maintaining them in closed relation, a magnetic device for tripping the latch mechanism, a self-closing circuit breaking device connected in series with said contacts and a shunt connection for the magnetic device bridged by the self-closing device. n

11. In a device of the character described, the combination of a snap switch mechanism mounted upon a base formed of insulating material, a circuit breaker having the contacts thereof connected in series with contacts of the snap switch mechanism, the circuit breaker being mounted on the opposite side of the base'fan operating member in the form of a revoluble stem extending through the base for closing and opening the snap switch contacts and for closing the contacts in the circuit breaker, a magnetically released detent mechanism for latching the circuit breaker contacts in closed position including a solenoid, and a bimetallic thermostatically actuated circuit breaking device connected in series with the contacts and bridging a shunt connection for the solenoid, said operating member carrying means for closing the separable contacts ofthe circuit breaker consequent to operating movement thereof.

12. In a device of the character described, the combination of a snap switch mechanism, a supporting base therefor formed of insulating material, 4an operating member having a resilient connection with the movable contacts of the snap switch mechanism, said connection being in the form of a spring whereby the spring may be tensioned to actuate the contacts, a circuit breaker mounted on the opposite side of the base, means actuated by the operating member and extending'through the base for closing the circuit breaker contacts during the spring tensioning movement of the operating member, and automatically actuated detent mechanism for normally maintaining the circuit breaker contacts closed.

13. An electric circuit controlling device comprising manually separable contacts and other automatically separable contacts, a manually operable member for closing both sets of contacts, means connecting all of said contacts in series, a latching mechanism for holding the automatically separable contacts closed, a magnetic device for tripping the latching mechanism, said magnetic device beina normally electrically connected in Vmultlple, relative to the means connecting the contacts in series, and a self-closing and opening circuit breaking device normally closed and connected in series with -said contacts, bridging the shunt connection for the magnetic device.

.14. In a device of the character described, the combination of a sna switch mechanism, a. base member supporting the snap switch mechanism on one side thereof, a circuit of the base member, an operating member extending through the base and arranged to operate the snap switch, and a cam mounted on the operating member for closing the circuit breaker contacts.

15. In a device of the character described, the combinationlof a snap switch mechanism, a base formed of insulating material supporting the snap switch mechanism, a separable pair of contacts comprising a circuit breaker mounted on the opposite side of the base, an cperatin member for the snap switch extending t rough the base, a spring mounted on the operating member for actuatin the snap switch mechanism, a cam carriedy the operating member for closing the contacts of the circuit breaker a'iatch mechanism mountedon the base ad]acent the separable contacts ofthe circuit breaker formaintaining them* in closed relation a magnetic device for tripping the latch. mechanism, elec'- trically. conductive means connecting the snap switch mechanism contacts and the conp ing the trip coil and responsive to variations in the current through the circuit breakerI to open the shunt circuit under predetermined current conditions.

17. The combination with a circuit breaker having a current-responsive and inductivel current-limiting trip means 1n series wit the c1rcu1t breaker, of a current-responsive resetting' device inseries with the circuit breaker and normally shunting the trip means and responsiveto'variations in the current through the circuit breaker to open the shunt circuit under predetermined current conditions. v t t In testimony whereoffIhereunto aix my signature.l

JOEL R. COOK.

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