US1842339A

US1842339A - Assiqkob

Info

Publication number: US1842339A
Authority: US
Publication date: 1932-01-19
Anticipated expiration: 1949-01-19

Description

Jan. 19, 1932. L. F. DOEN I FUEL SUPPLY CONTROL AND IGNITION SYSTEM Original Filed Jan. 19, 1925 2 Sheets-Sheet Jan. 19, 1932. L. F. DOEN FUEL SUPPLY CONTROL AND IGNITION SYSTEM Original F iled Jan. 19, 1925 2 Sheets-Sheet 2 enfoz MW,

anal/hum,

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, Patented Jan. 19, 1932 UNI-TED STATES PATENT oer-10s LOBAN I. DOEN, OF CLEVELAND, OKIO, ASSIGNOB, BY assronmrs, '10 'I'EE PA'I' BOL VALVE comm, OI CLEVELAND, 0310, A; GORPOBA'JI'ION OF OHIO FUEL SUPPLY GONTBOL AND IGNITION Application filed January 18, 1925, Serial No. 3,833.; lenewtd Kay 14, 1981. f

This invention relates to im rovements in gaseous fuel supply control an ignition systems for use in connection with apparatus or devices using gaseous fuels, and the like, the

present embodiment of the invention being particularly designed and adapted for use 'in connection with automatic hot water heating 7 systems, such as hot water storage tanks and hot water heaters.

10 The primary object of the invention is to 7 provide a generally improved control and ignition system or apparatus of the type or class indicated,- which will be exceedingly simple in construction, and efficient and economic in operation. l.

A further and important object is the provision of an improved system or apparatus particularly applicable and advantageous for use in connection with the so-called constant temperature water storage systems, the presthe admission of fuel to the main or fuel 3o burner and to a thermal actuating or con trolling flame in lighting proximity .to the pilot light so that in the event of the latter being accidentally blown 'out the supply of gas'to the burner will be cut "oif, said thermostatic valve being of dual formation, having one port" leading to the'control flame operated from the pilot light and'another port leading to the fuel burner.

The dual valve and its thermal element are 40 flamefed from the port or conduit-leading from said dual valve, the latter being adapted in one posit-ion to open the flow" of fuel to the main burner and cut off the flow of fuel to the control flame nozzle and in another position to cut off the flow of fuel to the main or fuel burner and open and permit the flow of fuel solely to the control flame nozzle.

A still further and very import-ant object is the provision of an improved flame concontrol flame operated thermostatic valve of y the quick acting snap type adapted to be quickly and positively moved to its respective operated solely by' the safety or control trolled thermostatic valve and control flame supporting port or nozzle operated and con-' trolled thereby and arranged in lighting proxlmity to t e pilot light, the relative arrangement and disposition of the parts being such that the thermal element of the valve is only subjected to the action of the safety or control flame while the latter is heating the thermal element preparatory to shifting the dual valve for cutting off the flow of fuel to the control flame supporting nozzle and for directing the fuelsolely to the main or fuel burner. A still further object is the provision of a positions and to positively retain such positions until shifted.

With the above mentioned and other ends in view, the invention consists in the novel construction, arrangement and combination of'parts, hereinafter described, illustrated in one of its embodiments in the accompanying drawings, and particularly pointed out in the appended claims.

Referring to the drawings, forming a part of this specification, Figure 1 is a side elevation, partly in section, of my improved thermostatically controlled fuel supply and ig-- nition apparatus or system applied to an or dinary storage tank and hot water heater.

Fig. 2, an enlarged vertical sectional view of the dual flame controlled thermostatic valve, the control flame port or conduit being open and the fuel issuing from the control flame nozzle being ignited by the auxiliary or igniting flame of the pilot nozzle thereby heating the thermal element and shifting the dual valve to its reversed open position, thereby cutting off thecontrol flame supporting fuel and opening the fuel supply conduit to the main or fuel burner.

' tional view, taken on line H of Fig. 2.

Fig. 5, an enlarged vertical transverse cross sectional view, taken on line 5-5 of Fig. 2.

trol and ignition system applied to or incorporated inv a constanttemperature storage water system consisting of a suitable storage tank or reservoir 1, and hot water heater 2, provided with the usual connections. The

storage tank 1 and the heater 2 may be of any suitable and convenient form or type. In the present instance, the hot-water heater is mounted at the side of the storage tank 1 and the coils of the heater are provided with inlet and

outlet'water connections

2 and 2", to provide for a proper heating and circulation of the water.

The flow of gaseous fuel to the various parts hereinafter referred to is automatically regulated through the medium of tank and flame controlled thermostatic valves, as hereinafter referred to.

In the present instance the fuel supply conduit 3, is in the specific form of a fuel supply or feed pipe communicating with a suitable source of supply and said conduit 3 is provided with a thermostatic valve 4, provided with a suitable thermo element extending into the water in the storage tank 1 and adapted to open and close the valve-4, as certain predetermined minimum and maximum temperatures of the liquid being heated are reached. The temperature control valve 4 may likewise be of any suitable and convenient form or type and forming no specific part of the present invention need not be described in detail. 4 I

A suitable shut-off valve 5, controlled by a handle 5, is preferably mounted in the supply conduit 3 above the temperature controlled thermostatic valve 4, and as a means of providing a constant supply of gaseous fuel to the pilot light nozzle 6, at the side of the main or fuel burner and in lighting proximity to the control flame nozzle hereinafter referred to, a valve 7 is mounted at the side of the fuel feed conduit 3 and communicates with the latter above the shut-off valve and temperature control valve, said valve 7 being adapted to be opened and closed through the medium of an operating head 7 and the valve 7 communicating with the pilot light or nozzle 6 through the medium of a suitable supply or conduit pipe 7".

As a means of providing a dual flame controlled thermostatic valve in the fuel supply conduitfor controlling the admission of fuel to the main or fuel burner, and also providing a valve controlled thermal actuating or control flame in lighting proximity to the pilot light so that in the event of the latter being extinguished-the supply of gas to the burner will be cut off, and particularly as a means of only subjecting the thermal element of the valve to the action of heat when is open toopen communication to the main or fuel burner 9, and the other port or seat 8", when the valve is open communicating with the control flame supporting nozzle 10,

through the feed pipe or conduit 10. The valve 8 is mounted on a stem 8, and is connected through the medium of suitable inter- -mediate elements such for example,as the quick acting snap'elements shown and hereinafter more fully described,to a thermal element 11, mounted in a position to be operated or controlled by a safety or control flame 10", when the control flame supporting end nozzle 10 is supplied with fuel through the opening of the flame controlled dual valve and the cutting ofi of fuel to the main burner. In the present instance, the control flame supporting nozzle 10 is mounted and formed separate from the pilot light supporting nozzle 6 and the control flame supporting port is arranged in lighting proximity to the pilot 1 light. For the purpose of facilitating the ignition of the gas issuing from the port of the nozzle 10, the pilot light nozzle 6 is provided with a main port for supplying the pilot light flame 6* in the usual manner and in lighting proximity to the ports of the fuel burner 9, and a second or auxiliary port for supporting a second or auxiliary jet or lighting flame 6 adapted to intersect the path of the fuel or gas initially issuing from the port of the control flame supporting nozzle 10.

As a means of supporting and housing the intermediate or snap quick acting elements of the thermostatic valve including the thermal element 11, a valve casing 12 is provided, said housing or casing 12 being preferably provided at its front with a suitable opening to receive the thermal actuating or control flame 10 and also provided with vertically extending side walls or projections 12", to afford additional protection to the pilot and control flames as against draught, or the like.

In the present instance, the thermal element 11 is in the specific form of a curved spring shaped member connected at its top by means of an attaching element or bolt 11*, extending through the top wall of the casing 12, the lower or free end of the thenmal element being connected to a' link 13, connected to a vertically arranged longitudinally movable toggle actmg member 14, the latter acting in conjunction with the spring resisted toggle elements-14, having the inter osed spring 14", these toggle acting elements eing removably and adjustably secured in position by means of the securing and adjusting pin 14. A second set of

toggle actingelements

15,and 16 with an interposed spring 16 and a securing pin or adjusting element 16 is and the relative disposition and arrangement of the companion sets of toggle acting memhers is such that the lug 160, being of greater lateral width than the lug 14d, and being unconnected to' the thermostatic actuator 11, tends to hold the valve 8 in one of its extreme positions, whereas the lug 14d being relatively narrow laterally with respect to the lug 16c, and being controlled by the actuator 11, serves to actuate the'valve 8 from one of its extreme positions to the other. The lateral width of lug 160 is such that it prefer ably substantially fills 'the space between the blocks 17. The lugs 14d and 160 are preferably of truncated cylindrical form or disc-like shape in order that their contacting faces will be spaced the same distance apart for each operating position of the toggle members 14 and-15 by which they are respectively carried. The toggle member 15, is so I adjusted that its dead center position is substantially mid way between the extreme positions of the valve member 8, the spring 16a being adapted to tend to hold the valve member in one or the other of its extreme positions, depending upon the setting of the valve to one or the other side of its dead center position.

The lug 14d that is carried by the toggle member 14 is preferably of materially less diameter or lateral width than the corresponding lug 160 of the opposed toggle member. The toggle member 14 is preferably so arranged that it can move from its extreme position slightly beyond its dead center position iii-each direction beforeit contacts with the-opposed block- 17- of the actuating valve stem 80. In this way the thermostat element 11 is only required to do sufficient work to overcome the resistance of the spring 14?) in moving the toggle joint from one extreme position to a point past its neutral position. When the toggle member 14 passes its neutral position, the action of the spring of the toggle member 14 serves to assist the thermostatic strip 11 to continue the actuation of the valve.

The thermostat strip 11, assisted by the force of the spring 14?), overcomes the resistance the valve to a point where the toggle member 15 passes its dead center position. This causes the valve to move to its other extreme position with a snap action because both of the

toggle members

14 and 15 and the thermostat lsl assist each other in actuating the valve 8 to its other extreme position after the toggle 15 passes its dead center position. This provides a quick acting mechanism which will quickly and positively move the control flame operated thermostatic valve to 1ts respective positions and positively retain same in such positions until the thermal element has been again actuated to repeat the cycle of operation. 14 and 16 and the blocks 17 on the stem 8, A

s a means of controlling the amount of gaseous fuel entering into the main burner when the valve is open, a suitable fitting 18 may be connected to the neck of'the burner and to the fuel feedconduit below the dual valve, said fitting being provided with suit able seats and a needle valve 18 and, if desired, the casing of the duel valve may be provided with a fitting 19, having suitable seats and a needle valve 19, the fitting or stantially as follows. Gas is admitted to the constantly burning pilot 6 from the adjustable valve 7. If the pilot flame 6a is ignited,

and the valve 5 opened, gas would advance through the main 3 to the thermostatically controlled valve 4. If the liquid in the tank 1 is cold, the valve 4 will be open and will admit gas to the supply port of the valve 8.

The valve 8 will be closed to the admission of fuel to the burner 9 because the thermostat ing the dead center position, the force of the spring 14b assists the thermostatic element to carry the toggle member to the end of its stroke in the left-hand direction. In so moving. the lug 14d of the toggle engages the block 17 and moves the valve stem 80 in the direction of movement of the toggle. The right-hand block 17 engages the lug 160 of the toggle 15 and moves the toggle 15 with the valve stem 80 to a position beyond its dead center position. When the toggle 15 reaches its dead center position, it assists the toggle 14, and the thermostatic actuator to move the valve to its extreme left-hand position with a snap action, thus closing the valve on seat 8?), as will be readily understood. The movement of the valve head 8 from its seat 8 a admits gas to the main burner 9 which is ignited from the pilot flame 6a. The heat thus developed tends to heat the water contained in the tank 1.

The thermostatheating flame 10!), having been substantially cut off by the movement of the valve head 8 to its extreme left-hand position, permits the. thermostat element 11 to cool slowly. The speed of cooling of the thermostat metal is relatively slow because of the heat transmitted thereto from the main burner 9 and, therefore, the closure of the fuel supply port of the valve 8a is greatly delayed. If, however, the thermostat strip 11 does cool sufiieiently to cause the valve 8 to again out off the main gas supply to the main burner, the heating flame 10b ofthe supplemental heating pilot will again be ignited and will again heat the thermostat actuator to again reopen the valve. The second action of the valve is much more rapid than the original opening of the valve by reason of the preheating of the controlling device with the result that there is no material interruption in the operation ofthe main burner 9 until the water of the tank 1 is heated to a point where iteauses the thermostat 4 to cut off the supply of fuel to the main burner. lVith the closing of the thermostat valve 4, by reason of the temperature of the water contained in the tank 1, the operation is not started again until the thermostatic valve 4 is again opened by the cooling of the water in the tank 1. The thermostat valve 4 may conveniently be a slow acting valve.

Having thus described one of the embodiments of the invention, without having attempted to set forth all the forms in which it may be made, or all the modes of its use, what is claimed and is desiredto be secured by Letters Patent is,

l. A fuel feed control and ignition system for hot water heaters, comprising a storage tank controlled fuel feed and a pilot light controlled fuel burner, and a thermostatically actuated dual valve having a port terminating in a control flame in lighting proximity to said pilot light, said dual valve having a second port supplying said. fuel burner when said control flame port is closed.

2. A fuel supply control and automatic ignition system for'hot water heaters, and the like, comprising, in combination with a fuel supply conduit controlled by a thermostatic valve governed by the temperature of the liquid within the storage tank and a pilot flame controlled burner connected with the fuel supply conduit through a dual valve governed by a flame controlled thermostatic element and a control flame fed and controlled by said dual valve of said pilot light control flame, said dual valve being adapted in one position to open the flow of fuel to said burner and cut off the flow of fuel to said control flame. I

3. In an automatic hot waterheating system, the combination with a heating receptacle, a fuel burner for the latter, a fuel supply conduit, a thermally actuated valve controlling the fuel supply to said burner from said fuel supply conduit, a pilot flame adjacent to said burner including an independent source of fuel supply, an independent control flame in lightmg proximity to said pilot flame, and means for supplying fuel to said control flame to cause the same to supply heat for the actuation of said thermally actuated valve when it is desired to ignite the fuel burner whereby the valve is opened and fuel is supplied to the main burner.

4. In a device of the character described, the combination with a thermostatically controlled fuel feed pipe terminating in a main burner and an independently fed pilot light having main and auxiliary pilot flames; of a second pilot light adapted to be ignited by said auxiliary pilot flame and provided with a second thermostatically operated valve in said main fuel supply pipe, said second thermostatically actuated valve operating in one position to supply fuel to said second pilot light and in another position to cut off the flow of gas to said second pilot light and open the flow of gas to said main burner.

5. In a device of the character described, a storage tank, a fuel supply conduit provided with a thermostatic valve controlled by the temperature of the liquid within said tank, a burner connected to said fuel supply conduit, a pilot light provided with a fuel conduit supplied independently of said temperature controlled thermostatic valve, and a second pilot light communicating with said main fuel supply conduit through a second thermostatic valve operated and controlled by said second pilot light, said secondthermostatic valve being adapted in one position to open the flow of fuel to said burner and cut off the flow of fuel to said second pilot light and vice versa in another position.

6. A gaseous fuel supply and ignition system, comprising a fuel feed conduit provided with a thermostatic valve controlled by the temperature within the storage tank and provided with a pilot light controlled main burner, a second thermostatic valve in said fuel feed conduit provided with a second fuel feed conduit terminating in a control flame in lighting proximity to said main burner and pilot light and adapted to be ignited from the latter, said second thermostatic valve being operated solely by the control flame of said second conduit and being adapted in one position to open the flow of fuel to said main burner and cut off the flow of fuel to said control flame and in another position to cut off the flow of fuel to said main burner and open the flow of .fuel solely to said control flame. a

7. In a safety heating system, in combina tion with a heating receptacle, a gas burner therefor, and a gas supply; of a thermally actuated valve adapted to control the gas sup- I stant amount of gas to said pilot flame, and

means for supplying gas to said control flame nozzle to ignite the same from said pilot light whereby to cause the same to impinge upon and actuate said thermally actuated valve when it is desired to ignite the burner and whereby the gas is cut off from said control flame and gas is supplied solely to the main burner.

8. In a fuel supply control and ignition system for hot water heaters and the like, in combination with a storage tank, and a communicating hot Water heater therefor, a fuelburner for the latter, a source of gas supply, including a thermostatic valve controlled by the temperature of the water inv said tank, a flame controlled thermostatic valve arranged in one position to open the supply of fuel to the fuel burner and in another position to cut off the supply of gas thereto, a source of fuel supply leading from said flame controlled thermostatic valve and terminating in a control flame supporting nozzle adapted to operate said thermostatic flame controlled valve, and an independently supplied continuously burning pilot flame a jacent to said fuel burner and control flame nozzle and adapted to ignite the latter when fuel is supplied thereto whereby said thermostatic valve is opened to cut off the flow of fuel to said control flame and is opened for the supply of fuel to said burner.

9. In a device of the character described, a storage tank, a fuel supply pipe provided with a thermostatic valve controlled by the temperature within said tank, a fuel burner, a pilot light provided with a feed pipe communicating with said main feed pipe independently of said temperature controlled thermostatic valve, a flame controlled thermostatic fuel valve in said fuel supply conduit including a thermal actuating and controlling flame supporting nozzle in proximity to saidpilot light and controlled by the latter whereby upon a predetermined relatively high temperature in said storagetank and the closing of said first mentioned thermostatic. valve, said flame controlled thermostatic fuel valve will be moved to a position to cut off the flow of gas to said fuel burner and upon a predetermined relatively low tem- 65 perature said first valve will be opened and said control flame will be ignited from-said pilot flame and said flame controlled thermostatic fuel valve will be moved to a position to support combustion at said burner and close said valve with respect to said thermal control flame.

10. In a device of the character described, astorage tank, a fuel supply pipe provided with a thermostatic valve controlled by the temperature of the liquid within said tank,"

a fuel burner for said heater, a pilot light provided with a feed conduit above said thermostatic valve, a flame controlled thermostatic valve in said fuel'supply conduit, including a thermal actuating and controlling flame in proximity to said flame controlled pilot light, said thermostatic fuel valve being of dual formation having one port leading to said thermal control flame and the other to saidv fuel burner whereby upon a predetermined temperature in said storage'tank and the closing of said first mentioned thermostatic valve, said second or flame controlled valve will be to said main burner, and upon a predetermined temperature said temperature controlled valve will be opened and said control flame will be ignited from said pilot light and said fuel valve will be moved to a position to support combustion at said burner and close said control flame.

11. In a fuel supply control and automatic ignition system for hot water heaters, means for automatically maintaining storage water at a constant temperature, comprising incombination with a storage tank and a hot water.

heater therefor and a fuel burner and fuel supply conduit; of a thermostatic flame controlled fuel valve in said fuel su ply conduit,

including a conduit adapted to intermittently support a control flame in roximity to said burner and thermostatic flame controlled valve, a continuously burning pilot flame adj acent to said fuel control flame and adapted to ignite the latter when fuel is supplied ame thereto and to actuate said thermostatic age tank for automatically increasing the supply of fuelto said conduit when the temperature therein falls below a predetermined point whereby said control flame will be ignited to move said thermostatic valve to open communication to said fuel burner and close the supply of gas to saidcontrol flame to repeat the cycle of operation until a predetermined higher temperature is reached in said storage tank and said first thermostatic valve is closed. 1

12. In a device of the character described, a fuel supply conduit provided with a thermostatic valve controlled by the temperature 'of the liquid being stored, a burner connected to said fuel supply conduit, and a pilot light connected to the latter above said thermostatic valve, an intermittently actuated flame controlled thermostatic valve in said fuel supply conduit provided with a, fuel supply conduit adapted to support a control flame in operative proximity to said pilot light and flame controlled thermostatic valve, said second thermostatic" valve operating in one position to supply fuel solely to said flame supporting fuel supply conduit for opening said valve and closing said supply valve relatively of said flame supporting conduit whereby when the control flame has accomplish-ed its valve operating function the fuel will be supplied solely to the burner until either the cooling of the flame controlled thermostatic valve due to the extinguishment of said control flame causes the shifting of this valve or until a predetermined higher temperature in the liquid being heated closes said first thermostatic valve cutting ofl the flow of fuel to said burner and control flame until a lowered temperature is reached and operates the first valve whereby said fuel will again pass to said control flame supporting conduit to ignite and actuate said second thermostatic valve to repeat the cycle of operation. I g

13. In a fluid fuel control system, a fuel supply line, a main heating burner adapted for communication with said supply line for supplying heat to the medium to be heated, means in said line providing an automatically operated double control of the fuel supplied to said main burner, said means comprising a primary fuel control valve controlled in the normal operation of said system by the temperature of the medium being heated for cutting off the flow of fuel in said line at a predetermined temperature of the medium and for permitting the flow of fuel in said line when the temperature of themedium is less than the said predetermined temperature, and a secondary fuel control valve having temperature responsive actuating means whereb to also control the flow of fuel to said main urner and whereby, upon the medium reaching said predetermined temperature, both said valves shut off the flow of fuel, thereby providing a double fuel control for said main burner, and a constantly burn ingpilot for igniting said main burner operatable independently of said primary and secondary valves. Y

14. In a fluid fuel control system, a fuel supply line, a main heating burner adapted for communication with said line for supplying heat to the medium to be heated, a constantly burning pilot for igniting said burner, and means for controlling the flow of fuel in said line to saidmain burner, said means comprising a control valve in said line controlled in the normal operation of said system by the temperature of the medium bein heated, said valve being arranged to cut ofl the flow of fuel in said line when the medium being heated reaches a predetermined temperature and to permit the flow of fuel when the medium being heated drops below said predetermined temperature, a thermally operated valve in said line between said control valve and main burner and operatable, when said control valve permits the flow of fuel to control the flow of fuel to said main burner, and an intermittently operating auxiliary burner in communication with said line and arranged to be ignited by the flame issuing from said constantly burning pilot for supplying the heat for actuating said thermally operated valve.

15. In a safety fluid fuel control system, a main burner, a thermally actuated valve for controlling the fiow of fuel to said main burner, a constantly burning pilot for igniting said main burner, an intermittently burning burner arranged to be ignited by said pilot and disposed to supply heat for actuating said valve whereby said valve may cut off and admit fuel to said main burner, and temperature responsive means arranged during normal operation of said system to admit fuel to said valve, said means serving to cut off the supply of fuel to said valve and intermittently burning burner independently of the operation of said pilot, whereby to doubly insure against the passage of fuel to said main burner when the medium being heated is at the desired temperature.

16. In a fluid fuel control system, a main burner, a thermally actuated valve for con trolling the supply of fuel to said main burner, an auxiliary burner for supplying heat for actuating said valve, a constantly burning pilot adjacent said auxiliary burner and mainburner 'for'igniting the same when fuel is supplied thereto, and means for controlling the supply vof fuel to both said thermally actuated valve and said auxiliary burner during the normal operation of said system without afiecting the operation of said pilot.

17. In a fluid fuel control system, a'main burner for supplying heat to the medium being heated, an intermittently burning burner, a thermally actuated valve for controlling the supply of fuel to both said main burner and intermittently burning burner and arranged to be actuated by the heat supplied by said intermittently burning burner, a constantly burning ignition pilot for igniting said main and intermittently burning burners when fuel is supplied thereto, and means for cutting ofi the supply of fuel to said intermittently burning burner during normal operation of said system to doubly insure the cutting off of the supply of fuel to said main burner.

18. In a safety aseous fuel control system, a main burner, a t ermally actuated valve for controlling the supply of fuel to said main burner, an auxiliary burner for supplying heat to actuate said valve, a constantly burndependent of the operation of said single means for supplying gas to said ignition pilot.

19. In a fluid fuel control system, a heat supplying fuel burner, a fuel supply conduit therefor, a thermally actuated valve for controlling the supply of fuel to said burner from said conduit, a constantly burning pilot adjacent to said fuel burner for igniting the same, an auxiliary burner in lighting proximity to said constantly burning pilot for supplying heat to cause the actuation of said valve whereby said valve may open and per-- mit the flow of fuel to said main burner, a, fuel supply means for said auxiliary burner, a plurality of means for controlling the flow of fuel to said auxiliary burner and means for supplying fuel to said pilot independently of the operation ofsaid plurality of means.

20. In an automatic fluid fuel control system, a main fuel burner, a fuel supply conduit adapted for communication with said burner, a thermally actuated valve for controlling the supply of fuel to said burner from said fuel supply conduit, a constantly burning pilot adJacent said burner including an independent source of fuel supply, an independent control burner in lighting proximity to said pilot for supplying heatffor actuating said valve, whereby fuel may be supplied to said main burner upon actuation of said valve, and thermostatic means controlled during normal operation of said system by the temperature of the medium being heated for controlling the supply of fuel to both said thermall control burner in ependently of the operation of said pilot.

21. In a fluid fuel control system, a main burner, a thermally actuated valve to control the flow of fuel to said main burner, an intermittently burning burner for supplying heat for the actuation of said valve, a constantly burning pilot for igniting said main burner and intermittent burner, means controlled by the temperature of the medium being heated by said main burner for controlling the supply of fuel to said intermittent burner during normal operation of said system, and

means inde endent of said first means for supplying uel to said constantly burning pilot.

22. In a fluid fuel control system, a main burner, a thermally actuated valve to control the flow of fuel to said main burner, a constantly burning ilot, an auxiliary burner adjacent thereto or supplying heat for the actuation of said valve, means to admit fuel to the auxiliary burner to open said valve and supply fuel to the main burner, and means operatable during normal operation of said actuated valve and said system independently of the operation of said pilot to cut off the supply of fuel to the main burner and the auxiliary burner.

23. In a fluid fuel control system, a main burner, a thermally actuated valve to control the flow of fuel to said main burner, a constantly burning pilot, an auxiliary burner adjacent thereto for supplying heat for actuating said valve, means to admit fuel to the auxiliary burner to open said valve and supply fuel to the main burner, and thermostatic means operatable during normal operation of said system to cut off the supply of fuel to the main burner, the valve and the auxiliary burner. 1 y

24:. In a fluid fuel control system, a main burner, a thermally actuated valve controlling said main burner, a constantly burning pilot, an intermittently burning burner adjacent thereto for supplying heat for the actuation of said valve, temperature responsive means operatable durinv normal operation of said system to admit filel to the valve and to the intermittent burner to open the thermally actuated valve and admit fuel to the main burner, said means also serving to cut off the supply of fuel to the main burner, the thermally actuated valve and intermit tent burner and means unaffected by the operation of said temperature-responsive means for supplying fuel to said pilot.

In testimony whereof I have affixed my signature.

LORAN F. DOEN.