US1619219A - Automatic regulating apparatus for car heating systems - Google Patents

Description

BEST AVAILABLE com March 1927.

v EA. RUSSELL.

AUTOMATIC REGULATING APPARATUS FOR 01m HEATING SYSTEMS 2 Sheets-Sheet 1 Original Filed Julys, 1925 Imfnt 'MW/ f? w -FeL BEST AVAILABLE com March 1, 1927. 1,619,219

E. A. RUSSELL AUTOMATIC REGULATING APPARATUS FOR CAR HEATING SYSTEMS Original Filed JulyG, 1925 2 Sheets-Sheet 2 3 ,3 45/ 26 5 3 049 l ii a I l:

? aw w 1 11934 Infenm.

Patented Mar. 1, 1927.

UNITED STATES BEsr AVAiLABLE coP- PATENT OFFICE.

ED'WARD-A. RUSSELL, OF CHICAGO, ILLINOIS, ASSIGNOR T0 VAPOR CAB HE ATING COMPANY, INC., OF CHICAGO, ILLINOIS, A CORPORATION OF NEW YORK.

AUTOMATIC REGULA'IING APPARATUS FOR CAR-HEATING SYSTEMS.

Application filed July 6, 1925, Serial No. 41,779. Renewed July 17, 1926.

My invention relates to a car heating system provided with two controls, one becoming effective automatically when the car is put into service to maintain a relatively high temperature, 70 Fahrenheit, l'or cX ample, and the other made eti'ectivc. when the car is cut off from the locomotive and supplied with heating medium i'rom a yard or terminal steam line for niaiutaining the car atmosphere at a lower temperature, 5t)" Fahrenheit, for example. A car heating system operating in this manner is shown, for example, in .United States patent to Edward-A. Russell No. 1,440,701, January 2, 1923,-t he apparatus disclosed comprising two control thermostats functioning at respectively high and low temperatures which are put into sponse to: the appearance and disappearance of air pressure in one of the air train pipes of the car. When the car is operatively connected up with the. locomotive the air train line is under pressure and through operation of a selecting device the control ling mechanism maintains the car atmosphere at the higher temperature. When the car is cut ofl' from-the locomotive and sent to the train yardthe pressure in the air train line disappears and the selecting device throws the control over upon the low temperature thermostat so that the car temperature is maintained at a'lower point. Fuel economy is the'lnotive for this dual control.

The temperature tregulating system referred to is ordinarily provided.'with a circuit breaker or master switch by opening "which the controlling mechanism maybe disabled to permit the 'manual operation of the radiator valves. Such capacity for manual control is desirable in view of the possiblefailure of the automatic controlling apparatus to function properly under certain extreme and unusual conditions. But the provision of the apparatus with the master switch operable at will by the train crew hasthe disadvantage that the car may he sent to the' jyard with the controlling mechanism disabled so that when the car is connected up with the yard steam line it may be overheated or deprived of heat entirely according to the positions in which the radiator va ves have been left by the train crew.

control of the system in re- My invention provides a remedy for such mishandling of the system by furnishing the apparatus with means, whereby when the car is cut oil' from the locomotive, the heating system is automatically placed under the low temperature control regardless of whether the master switch. governing the controlling mechanism during periods of service is open or closed. a

It is sometimes desirable to put the system under the high temperature control when the car is not connected with the locomotive, for example, when the cars of.

the train are brought to the starting termi nal station. Heretofore this has been accomplished by manipulation of the air actuated selector switch, but only if the master switch of the electrical apparatus was;

closed. The arrangement of my present invention makes it possible to put the high temperature thermostat into control, when the air train line is not under pressure, even if the master switch has been left open, that is, by merely tripping the selector switch;

The invention is disclosed in a preferred embodiment in the accompanying drawings wherein Fig. 1 is a diagramillustrating the controlling mechanism as applied toa' steam heating system for railway cars.

Fig. 2 is a sectional view of-theautomatic electric'switch, air: actuated, .for making the low temperature automatic control effectivegardless -ofthe position -of- -the =master switch. e

Fig. 3 is'a'sectional' view 'on line-3-3 of Fig.2. Fig. 4 is a sectional view on line 474 of Fig. 2, and

Fig. 5 is a plan view of the-automatic switch.

Referring first to Fig. 1, A steam train line of the car; B, (J ing coils of the heating system; D the radiator valve which is o ened and closed by solenoids E and F; the-vapor regulator (the system shown being a system of the atmospheric type); H a limit switch cutting off the current to solenoids E or F at the end of the valve movement; J a relay for directing the flow of current either to solenoid E or solenoid F, K the low temthe radiatfor- I plate 20 area pair of clips 39, 40 for a fuse i perature thermostat, that is, the thermostat which is in control when the car is disconnected from the locomotive;-L the-high temperature thermostat; M the selectingdevice subject to pressure changes in one of the air train lines of the; car. for determining whether the system shall be under the high temperature or low temperature control; N a master *switch: forimaking the" controlling mechanism effective or ineffective while the car is in service, and O a switch subject to pressures in the air ,train line arranged in shunt with switch N andfunetioning so that when thecaniscut off from the locomotive it willfbe subject to the automatic control regardless of the position ofmaster switch N. P indicates a resistance to cut down the current flow through relay J and thermostats K andfLi' -"Theslupplygof electric current 15 indicated-Yat QF 1 p The switch ispreferablyconstructed as follows 1011s a cylinderconnected by pipe 11 to one of the air train 'pipe's of the car, for

ciram'ple, to thesignaltrain pipe although it mightbe connectedto the brake line. In cylinder 10 is a piston 12, the stem 13 of whichis proyidedwith a stud 14 of insulating -material' 'slotted at 15 for the rounded end 16' of a'lever17 which is pivoted to a "frame 18 by pin 19. The frame 18 is com 'pos'edofa 'sheet metal strip secured to an insulating plate by screw- 21.; Spacing sleeves 22 are arranged onv pin 19 on opposite sides of lever 17. The latter is formed with aniarcuate' sl ot 23 through which projects a ends vof which are secured in opposite sides offrame '18. The extremity of the lever 17- b'eyondslot 23 is in the form of a fork 25 which engages a stud 26 arranged'ina clevis 27'onthe end of a rod 28 which extends through an opening in a bridging member 29 provided at opposite ends-with contacts 30, 31, a coiled spring 32 being interposed between a collar 33 on rod 28'and the bridging member 29. The bridging member is formed with an arm 34 pivoted on pin 24. 35 is a contact plate secured to insulating plate 20 by binding post 36 having a contact 37 engageable by contact 30 on the bridging member. 38 is a similar contact plate secured to plate '20 by screw merely as a stop for the other end of the bridging member. When the plston 12 is raised lever 17 is rocked and with it rod 28. The contacts 30, 37 are not disturbed until the parts pass' center. Then the bridging member is moved'by snap action away from contact '37-and against the stop member 38.

On the opposite-side of the insulating 41, clip 39 being secured to plate 20 by binding post 42 and clip 40 by a screw 43 making an electrical connection between the fuse and frame 18.

BEST AVAILABLE Com The piston 12 in air 'c ylinder 10 is held in its lower position, when there is no pressure in the air trainline, by a coiled spring 46 and rests on 'a stud 47 projecting upwardly from a cross web 48 in'the bottom of the cylinder.

The other wiring of the apparatus, togethe-r with certain structural details not already mentioned, will be described in connection with the description of the operation. of the controlling mechanism which is as follows:

The parts are in the positions shown in Fig.

1 when the car iscut oi'f from-the locomotive and is being supplied with steam from a yard or terminal steam line. The temperature of the car is supposed to-be below that at which the low temperature thermostat K functions, that is, below 50 Fahrenheit, so

that radiator valve D is open and the heating coils receiving steam. USteam' passes from train line A through the vapor regulator G, thence through pipe 54 to chamber 55 of valve D, through the central space 56 of the valve, valve chamber 57 and then through the radiating coils B and C. Water of condensation (and steam when the coils are filled with steam) passes by way of pipe 58 to thethermost-at chamber of the vapor' regulator through valve chambers 59 and 60, in case of the discharge from coil C, and through valve chamber 61, port 62 and valve chamber 60,'in case of the discharge from coil B.

The steam heating apparatus shown is a vapor or atmospheric heating system. Vhen the radiator is filled with steam the excess passing through pipe 58 to the thermostat. chamber throttles inflow of steam to the coils.

So long as the conditions as above set forth prevail, the-relay J will be energized so that its bridging member 63 is held against the upper pair of contacts 64, 65, the circuit through the relay being-as follows:

HOt'rmitlNo. 1.'-Batt-ery Q, wire 66 (in which is arranged fuse 67) resistance P, wire 68, coil of relay =J,wire 69, fuse T0, master switch N',' wire71 to the battery; 38', but with no electrical function. It acts i If, however, the master switch N has been open during the period in which the car was in service, to disable'the automatic controlling mechanism and permit the manual operation of radiator valve D, and, through inattention, has been left open, as may well happen, when the car was cut off from the train and sent to the yard, the circuit as above described will be completed as follows: CirctaitiVo. JH- -Gircuit 1.to binding post 72 on wire 69;. wire-44 including fuse 41, electrical, connection 40, 43, 18 (represented for simplification as a wire in Fig. 1), lever 17, rod 28 and contact 30 on bridging member low temperature thermostat K reaches contact 75 (temperaturebf 50) a circuit will be closed through the low temperature thermostat 'whi'ch circuit is a shunt from circuit No. '1, and, when closed, deprives relay of current sufiiciently to deenergize the sa e; 'Thecir'cuit through the lo'w'tempera ture therh'lo'stat is as follows:

Qir'cu-it OJZL- Circ'uit No. '1 to binding post 76 at the" upper end of resistanceP,

wire 7?, mercury column 74, Contact 75,vkire *ragpmtg contactf79, oflthe' selector switch M,";conducting block 80 of the movable switch'l membjer 81*,of the selector switch, spring contact 82, wire 83,thence,to the bat- I teryieitherfthrough the master switch N or the switch: and No.1; 7 v j v fl hehrelay' l, deprived of current, drops thefbridging member 63 on contacts 84:, 85

Q describedincircuits N0. 1

- 'closina a circui t'through the coil of solenoid F 'a's' itutwss v I airmtit Nolfli- Circuit No.1 to binding post 86 on wirefifi wire 87, solenoid F, wire 8 8,"spriiig iicontact '89, conducting block 90 of switch spring contact 91, wire 92, colitact in member 63, contact 8 5,wire 93to'b 1nd1ng 'post 94; on wire 69, and thence to thebattery either through mastr switc'h N or'switch O. Solenoid'F,attr'actsits armature 95 mov- {ingrqd 96 to the left and turning the revoliible member'97, connected with rod 96 by lever 98, toaposition which shuts off steam from the radiator and allows the coils to drain.

As soonas the temperature in the car falls below Fahrenheit, the thermostat circuit' ci.rc1 iit No. 2Vis broken, relay J is energi zed bycurrent flowing over circuit No. '1, and ,thebridging member 63 is raised against the: upperpair of contacts 64L, closing a circuit through 'coil E is-follows:

Ci i'ciritNO 4.. Circuit'No. 3 to binding post 99 on wirel87, wire 100, solenoid E, Lwire 10 1 spri1ig"contact"102, conducting bloelr103' olthe'limit switch (which is now in its right hand positionso that contact 102 bears 'on' (block 103) spring contact 104:, wire 10 5, r'el'ay contact 64," bridging mem- "berit33,{contact"65 and thence through the master switchf N or";through the switch '0 The radiatorvalve is now shifted back to Lits'open position. 'As each movement of the h .valve'has been completed the limit switch is operated to break"tliecircuit to the then BEST AVAILABLE COP: a

energized solenoid, F or E," as the case may be. When thecar is put into service air from'the air train pipe p'as 'se's by pipe 106 to the cylinder 107 ofthe selector switch and moves piston 108 to the left-so as'to bring the insulating blockf'109 of movable switch member 81'between the spring contacts 79 and*82.' This"opens thelow temperature thermostat circuit (circuit No; 2) so that this thermostat will not function-at the 50"temperature, the control 'of the'heating system being thereby thrown upon the high temperature thermostat L. In other words, the relay J will be deenergizedand energized to bring about reverse movements of the radiator valvejat a'car temperature of, '(assuming *tl1e high temperature thermostatis set to function at this temperature) instead of 'atfa car-temperature of 50 I for which the low temperature thermostat is assumed to be set.-

I \Vitlr the car temperature below-70 the parts of the apparatus will remain as 'shown in Fig. 1. As soon'as the mercury 'column 110 of high temperature thermostat L reaches the contact point 111 of:this thermostat, a circuit will beclosed' through the high temperature thermostat as follows:

Circuit 1v0. 5.''CirouitNo. 2. to binding column 110, contact 1 11, and wire 114 to binding post-115 on wire 83, thence-to the battery through the master switch N provided the same is closed. I

hen the train is connected up with the locomotive and pressure is created in the air train line, with which pipe 11 isjconnected, piston 12 of the automatic switclrO is raised and 1ever'17is rocked so as to throw the bridging member 30 away from contact 37 against the dead contact or stop 38. This breaks the shunt' circuit around the master switchN so that the heating system may be either subjected to the auto matic control, by closing master switch N,

or maybe subject to hand control, through manipulation of radiator valve D, if the master switch N is open.

The operation of the apparatus under the high temperature control is the same, and the controlling circuit is the same as described in connection with the low temperature control except in the respects already noted.

Selector switch M is capable of manual operation with no pressure in the air line (at a terminalstat-ion for example, before the locomotive has been attached to. the cars) regardless of whet-her themaster switch N is open or closed. If the switch had been left open by-the train crew when the car was put out of service it may, remain open while the car was in the yard and when the car'was'brought-to the ter- --minal. The man at the terminal after conpost 112' on wire 77,,Wire- 113,- .merc'ury necting the steam train pipe of the rear car to the terminal steam supply line merely trips the selector switch, as will be described, =forthe purpose of throwing the control on the high temperature thermostats He is likely to .pay no attention to the position of master switch N. .l-Vith the apparatus as .herein gdisclosed, high temperature control is .obtained in this way even if the master switch be open.

..;The movable member 81 of selector switch M is normally; stopped in the .low temperature control position by a trip 116, which can be pulled out to allow spring 117 on fixed'abutment 118 to force the movable member 81 toward the inner end of cylinder -107 -,whereby.insulation 119 is interposed off from the between springs; .79, 82, the trip riding over theatopiof member 81 ready to drop behind .said. member when piston 108 is moved outwardly-by air pressure. The electrical connections arethesame whether the circuit is broken by insulation 109 or 119. That-is, the-low temperature thermostat is cut out and-the high temperature thermostat Putin-control. Now since with the car. out locomotive switch 0 is closed, the system will operate under the high temperature control, (assuming that the selector switch has been tripped as described) even if the master switch N is open because circuit No.1'kunder these conditions is a closed circuit. :1

As soon as the car is connected to the locomotive member 81 of the selector switch is moved outwardly under air pressure so that insulation 109 is between spring contacts 7 9,

82. The system remains under high temperature control but the apparatus is ready now to be thrown to the low temperature control as soon as the car is cut oil from the locomotive and the pressure in the air train line reduced to atmospheric pressure.

2 While the invention has been described in a preferred embodiment and as forming an improvement upon a specific type of control apparatus, to wit, that shown in the patent to Russell referred to, it will be understood that all modifications, adaptations and uses of the device are intended to be covered within the scope of the appended claims.

I claim:

1. In combination with electrically operated mechanism for automatically maintaining the car at a lower temperature when out of service than when in service, a circuit breaker whereby said controlling mechanism may be rendered operative or inoperative at will while the car is in service without affecting the automatic operation of said mechamsm when the car is put out of service.

2. In combination with electrically operated mechanismv for automatically maintaining the car at a lower temperature when out of service than when in service, a circuit breaker for putting said controlling'mechanism out of operation, and a switch shunted around said circuit breaker which is open when the car is in service and closed when the car is put out of service.

3. In combination with a heating apparatus, mechanism forcontrolling said apparatus to maintain a higher orlowertemperture in the vspace heated, an automatically operated selective device which determines whether the apparatus shall be subject to the high or low temperature control, and means whereby the controlling mechanism may be made ineffective when the selective device is in the high temperature control position without altecting its operativeness whenthe selective device is in the low .temperature control position.

el. In combination with a heating apparatus, mechanism for controllingsaid apparatus to maintain a higheror lower temperature in the space heated, a selective de vice which determines .whether the apparatus shall be subject to the high or low temperature control, and means whereby the controlling mechanism may be made ineffective when the selective device is :in the high temperature controlposition without afi'ecting its operativeness when the seleotived'evice is'in the low temperature control position.

5. In combination with a heating apparatus, mechanism for controlling said apparatus to maintain an automaticallly operated higher or lower temperature in the space heated, a selective device which determines whether the apparatus shall be subject to the high or low temperature control, and means whereby said controlling iechanism may be made inoperative when the selective device is in one position without affecting the operativeness of said mechanism when the selective device is in its other position.

6. In combination with a heating apparatus, mechanism for controlling said apparatus to maintain a higher or lower temperature in the space heated, a fluid pressure actuated selective device which determines whether the apparatus shall be subject to the high or low temperature control, and means whereby the controlling mechanism may be made ineffective when the selective device is in the high temperature control position without afiecting its operativeness when the selective device is in the low temperature control position.

7. In combination witha heating appar ratus, mechanism for controlling said apparatus to maintain a high or lower temperature inthe space heated, a fluid pressure actuated selective device which determines whether the apparatus shall be subject to the high or low temperature control, and

said controlling mechanism when the selec tive device is in one position, and a switch shunted around said circuit breaker which is opened when the selective device is moved to the aforesaid position and closed when moved to its other position.

, 9; In combination with a heating system, an electrically operated mechanism for controlling said apparatus to maintain a higher or lower temperature'in the space heated, an

automatically operated selective device which determines whether the apparatus shall be subject to the high or low temperature control,' fa circuit breaker to disable said controlling mechanism when the selective device is in the high temperature control position,and a switch shunted around said circuit breaker which is opened when said selective device is-movedto the aforesaid position and closed when saidselective device is moved to the low temperature control position.

I 10. In combination with a heating appaams, an electrically operated mechanism for controlling said apparatus to maintain a higher or lower temperature in the space heated, a fluid pressure actuated selective device moved to one position to subject the apparatus to the high temperature control and to another position to subject it to low temperature control, a circuit breaker to disable said controlling mechanism when the selective device is in one position, and a switch shunted around said circuit breaker which is opened when the selective device is moved to the aforesaid position and closed when moved to its other position.

11. In combination with a heating system,

an electrically operated mechanism for controlling said apparatus to maintain a higher or lower temperature in the space heated, -a fluid pressure actuated selective device moved to one position to subject the apparatus to the high temperature control and to another position to subject it to low temperature con- 'trol, a circuit breaker to disable said controlling mechanism whenthe selective device is inthe high temperature control position,

and a switch shunted around said circuit breaker which is opened when said selective device is moved to the aforesaid position and closed when said selective device is moved to the low temperature control position.

'ing said switch.

BEST AVAILABLE COP\ 5 12. In combination with a railway car, an air train line, a heatinE apparatus, electrically operated mechanism for controlling the heating apparatus to produce either a high or a low temperature in the car, a selective device actuated by pressure changes in the air train line for determining whether the heating apparatus shall be operated under the high or low' temperature control, a' circuit breaker to disable the controlling mechanism, a switch shunted aroundsaid circuitbreaker, and an air motor actuated by changes of pressure in said air line 'for opening and clos- 13. In combination with. a railway car, an air train line, a heating apparatusfelectri cally opera ted 'mechanism'for controlling the heating apparatus to produce either a high or low temperature in the car, a'selective device actuated with pressure in the" air train lin to bring about the high temperature control and one disappearance of pressure from the air line the low "temperature ;con trol, a circuit breaker to disable said controlling mechanism, a" switch shunted around said circuit breaker, and means actuated with air pressure in the trainline for opening said switch and on disappearance of pressure in' said pipe for/closing said switch. I j

14. In combination with a'ra-ilwaycar, a steam heating apparatus'comprising a radiator valve, electrically operated controlling mechanism for said valve comprising high and low temperature thermostats, a selective device for determining which of said thermostats shall control said mechanism, a circuit breaker to govern the supply of current to the controlling mechanism, a switch shunted around said circuit breaker, an air train line, and means actuated by pressure changes in said air train line for operating said selective device and opening and closing said switch.

15. In combination with a railway car, a steam heating apparatus comprising a radiator valve, electrically operated controlling mechanism for said valve comprising high and low temperature thermostats, a selective device for determining which of said thermostats shall control said mechanism, a circuit breaker to govern the supply of current to the controlling mechanism, a switch shunted around said circuit breaker, an air train line, and means actuated by pressure changes in said air train line for operating said selective device and opening and closing said switch so that the opening of the circuit breaker disables thecontrolling mechanism at the high temperature control, without affecting the operation of the controlling mechanism during the low temperature control. j

16. Anelectrical switch mechanism comprising a fluid pressure cylinder, a piston therein having a stem, a lever oscillated by.

said stem, formed with an arcuate slot and a fork, a .pin extending through said arcuate slot, a rocking member pivoted to said pin and having a bridging piece provided with a contact, a fixed contact engageable by said lastnam'ed contact, a rod engaged by the forkof said lever and loosely engaged with the bridging piece and formed with a spring abutment, and a coiled spring between said abutment and bridging piece."

17. In a car heatin apparatus, mechanism atomatically actuated when the car is connected with and disconnected from a locomotive for controlling .the heating apparatus to maintain the car at determinate high and low temperatures, respectively, whichmechanism can be set when the .car s disconnect .f ointhe o motive f h gh temperature control, andmeans for making said controlling mechanism inefi'ective when the .car is connected with .the locomotive without affecting itsoperation either for the high or low temperaturecontrol when the car is disconnected from the locomotive.

18. In a car heating apparatus, mechanism automatically actuated when the car is connect dwith'and disconnected from a locomotive for controlling the heating apparatus to maintain the car atmosphere at a determinate high temperature when the car is connected to the locomotive and at said high temperature 01' ata determinate low temperatureat will when the car is disconnected from the locomotive, and means for making ,said controlling mechanism ineffective when thecar is connected with the loco- .motive without afiiecting its operation when the car is-disconnected from the locomotive.

19. In combination. with mechanism for controlling a car heating system to maintain the carat a determinate low temperature when out of service and at a determinate high temperature when in service, which mechanism may be set to maintain the carat the high temperature when out of service, and means whereby said controlling mechanism may be rendered operative or inoperative at will while the car is in service without affecting its automatic operation for either the high or low temperature control whenthe car is put out of service.

20. In combination with electrically operated mechanism for automatically maintaining the car at a determinate low temperature when out of service and ,at a determinate high temperature when in service, 'which mechanism may be set to maintain the high temperature when the car is out of service, and a circuit breaker whereby said controlling mechanism may be rendered operative or inoperative at will while the car is, in service without affecting the automatic operation of said mechanism for either the high or low temperature'control when the car is put out of service.

21. In combination with electrically operated mechanism for automatically maintaining the car at a lower temperature when outof service than when in service, which mechanism may be set for maintaining the higher temperature when the car is out of service, a circuit breaker for putting said controlling mechanism out of operation, and a switch shunted around saidcircuit breaker which is open when the car is in service and closed when the ear is put out of service.

22. In combination with a heating apparatus, mechanism for controlling said apparatus to maintain determinate high or low temperatures in the space heated, an automatically operated selective device which determines whether'the apparatus shall be subject to the high or low temperature control which device whe n in the low temperature control position may be set manually to a third position to bring about the high temperature control, and means whereby the controlling mechanism may be madeineffective when the selectivedevice has been moved automatically to the high tempera-- turecontrol position without afiecting its operat-iveness when the selective device is in the low temperature control position or in said third position.

23. In combination with a heating apparatus, mechanism'for' controlling said apparatus to maintain determinate high or low temperatures in the space heated, at fluid pressure actuated selective device which determines whether the apparatus shall be subject to the high or low temperature control which device may be set manually from the low temperature control position to a third position bringing about'high temperature control, and means whereby the controlling mechanism may be made ineffective when the selective device has been moved automatically to its high temperature control position without affecting its operativeness when the selective device is in the low temperature control position or said third position.

24. In combination with a railway car, an air train line, a heating apparatus, electrically operated mechanism for controlling the heating apparatus to produce either a high or a low temperature in the car, a selective device actuated by pressure changes in 1,619,119 BESTAVAILABLE cop 25. In combination with a railway car temperature control position to a third poa steam heating apparatus comprising a sition subjecting the apparatus to high tem- 10 radiator valve, electrically operated controlperature control, a switch shunted around ling mechanism for said valve comprising said circuit breaker, an air train line, and 5 high and low temperature thermostats, a means actuated by pressure changes in said selective device for determining which of air train line for operating said selective said thermostats shall control said mechadevice and opening and closing said switch. nism which device may be set from its low EDWARD A. RUSSELL.

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