US2361944A - Safety control for gaseous fuel burners - Google Patents

Description

NOV. 7, 1944. w JACKSON r 2,361,944

SAFETY CONTROL FOR GASEOUS FUEL URNERs Filed May 14 1941 3 Sheets-Sheet 1 5m 27 flai Q '1 1 19 INVENTOR. 106% L v -W/LBUR E JACKSON? L T BY Wins I-LJ'EFFERS 6- ATTORNEY Nov. 7, 1944. w. F. JACKSON ETAL SAFETY CONTROL FOR GASEOUS FUEL BURNERS 3 Sheets-Sheet 2 Filed May 14 1941 WNW 1944- w. F. JACKSON El'AL 2,351,944

SAFETY CONTROL FOR GASEOUS FUEL BURNE1iS Filed May 14 1941 3 Sheets-Sheet 5 V 'I/l/ v 4,

INVENTOR.

WILBUR E JACK6ON8/ BY Worms H. Straws ATTORNEK Patented Nov. 7, .1944

UNI-TED STATE REISSUED 'wllbur F. Jackson. Lynwood. and mm a.

Jeflers, Los Angeles, Calif., auignors to Grays'on Heat Control, Ltd, poration of California V Application May 14, 1941, Serial No. 393,396

12 Claims.

This invention relates to safety controls for gaseous fuel burners and more particularly to controls for domestic water heaters and the like.

Fuel controlling devices have been proposed to permit manual opening of the pilot burner fuel passage and automatic opening 01 the main burner line only after the pilot burner is lighted. In normal operation the fuel supply to the main burner is thermostatically regulated .to main- .tain'the water to'be heated at a predetermined temperature. Should .the flame of the pilot burner be extinguished for any reason, the fuel supply to both the main and pilot burners is shut oil, and no fuel can flow through either burner until the device has been manually reset and the pilot burner relighted. Such safety devices have, however, involved the use of several valves which complicate the structure and detract" from its efliciency in'operation.

It is an object of this invention to reducethe number of parts required in such controls, while retaining the safety features thereof.

Another object of the invention is to ensure positive operation of the safetydevice when required. i

Another object of the invention is to avoid incomplete shut- 011 of the fuel, such as may be due to deposit of dirt between the valve seating" surfaces.

Another object of the invention is to shut off the flow of fuel to both'the main and pilot burners when the safety control operates.

Another object of the invention is to prevent operation of any other manual control which may be provided until after the manually controlled p lot burner has been lighted and the automatic safety control is operating.

Another object of the invention is to combine shut-oil, safety and thermostatic regulating devices into a simple, compact and reliable structure permitting economy in manufacture and facilitating installation and repair. v

Other object and advantages will become apparent from the following description taken in connection; with the accompanying drawings,

wherein Fig. 1 is a, plan view of the improved control;

Fig. 2 is a 'side elevation;

Fig. 3 is an and elevation;

Fig.1 4 is av longitudinal sectional view;

Fig. 5 is a section taken on the line 5-5 of Fig. 4 looking inthe directionindicated by the arrows;

Fig. 6 is an enlarged section taken on the line ll port 27,,

"AR 1 6 i948 Lynwood, Calif a cor- 3-3 of Fig. 3 looking in the direction indicated by the arrows;

Figs. 7. 8 and 9 are partial sections taken along the line l--1 of. Fig. 4 and showing different ,positions of the shut-off valve; and

Figs. 10, 11 and 12 are partial sectional views taken along the line Ill-40 of Fig. 4, showing the relative positions of the interlocking device for the shut-oil valve when the latter is in the positions of Figs. 7, 8 and 9, respectively.

' Referring more particularly to the drawings, the control comprises a casing I! provided at one end with a laterally extending intake nipple l1 and, at the other end with an outlet nipple i9 adapted to be connected by suitable pipingwith the main or heating burner of the water heater or other appliance (not shown).

The upper portion of the casing I5 is shaped to provide a tapered valve seat 2| within which a tapered plug cock 23 is seated. The plug cock 23 is provided with an axial bore 25 with which La port 21, extending through one wall of the cock 23, communicates. The port 21 aifords communication between the inlet nipple l'l and the bore 25 in order that ,the fuel may flow into the body of the casing I! when the cock is in the by a retainer plate 33 secured to the casing I! by I means of the screws 35 and overlying the shoulder 33 formed by the junction of the reduced stem 23 with the cock 23. A spring 31 is housed within a recess 33 at the junction of the stem 23 with the shoulder 30 and, by its engagement with the overlying portion of plate 33, serves to maintain the cook 23 resiliently in its seat 2|. A stationary reference point in the form of a depending flange 33 on plate 33 i provided to cooperate with the dial 3| as hereinafter described to indicate the various positions of the cock 23.

Rotation of the cock 23 in its seat is limited to substantially between full-open and fullclosed positions by the provision of an upstanding flange III on the plate 33 which enters the underside of the dial 3i and engages with either end of an arcuate abutment 42 formed thereon. The stem 29 of the cock is provided with a threaded bore 44 for the reception of an adjustable plug 43 which extends into the bore 23 and serves to regulate the flow of fuel through the 'I'he shut-on cock, which is constructed as described, is adapted for controlling fuel flow for both the main and pilot burners of the appliance. The pilot control includes an arcuate groove 48 formed in the seating surface of the cook 28 opposite the port 21. The seat 2I is provided with a similar but shorter arcuate groove 58 communicating with the inlet nipple II. A passage 82 extends from the seat 2I adjacent the groove 58 and communicates with a passage 54 extending obliquely across the casing I5 and terminating in a horizontal passage 88.

By referring to Figs. 7, 8 and 9, the flow of fuel in various positions of the shut-off cook 23 may be ascertained. In Fig. 7 the cock is shown in closed position designated by a notch 58 on the edge of the dial 3I marked "Off" (Fig. 1) and there is no communication between the inlet nipple I1 and the port 21 or between the arcuate groove 48 and the passage 52. Upon being rotated from the closed position the cock first reaches the pilot position, designated by a notch v88 on the edge of the dial 3|, marked Pilot (Fig. 1). This position is shown in Fig. 8 and the arcuate groove 48 is now in communication with the passage 52. The next position of the plug cook 23, upon further rotation, is the "on" position suitably designated by the notch 82 in the edge of the dial 3I and marked On. This position is shown in Fig. 9 and the port 21 in the cock communicates with the inlet nipple I'I while at the same time communication between the passage 82 and the inlet nipple I1 is afl'orded by the arcuate groove 48 extending across both the passage 52 and the groove 58 in the valve seat.

In order to facilitate positioning of the dial 3| in the pilot position a non-positive stop is provided which, as shown in Fig. 3, comprises a plunger 84 mounted within an aperture 88 formed in the underside of the dial 3| and yieldably urged into engagement with a depression 88 in the plate 33 by means of the spring I8. Thus, the "on and '01! positions of the shutof! cock are located by the positive stop and the pilot position by both an audible click and increased resistance to rotation of the dial afforded by the device described.

An end casing 58 is secured to the main casing I5 by means of the screws I2, and a gas-tight joint secured by the provision of a gasket I4 between these members. As shown in Fig. 6, the end casing 38 is provided with an adjustable plug I8 having a hollow threaded end I8 reclprocable in a threaded passageway 88 communicating with the passage 88 in the main casing. The hollow end of the plug 18 communicates with an aperture 82 in the plug body which may be moved into and out of registry with a passage 84 formed in the end casing 58. As will be apparent, rotation of the threaded plug will increase or diminish the eiIective area of aperture 82 and adjust the amount of fuel that flows through the passage 84.

The passage 84 communicates with a chamber 88 within which a pilot control valve 88 is housed. The pilot control valve 88 may be of any suitable form and, in this instance, is shown as being of the poppet type adapted to be moved into and out of engagement with its seat 88 against the pressure of a coil spring 92 retained in thechamber 88 by the cap 84. The stem 88 of the pilot control valve 88 is suitably grooved to permit the passage of fuel therearound and is guided in an opening 88 formed in the end casing. A sealing chamber I88 receives the projecting end of III the valve stem 88. Intermediate the chamber I88 and the valve seat 88 is an angular passage I82 communicatin with a passage I84 formed in the main casing I5. The latter passage communicates through a suitable coupling connection I88 with a conduit I88 connected as shown in Fig. 4 with a pilot burner II8. In order that leakage of gas from the pilot control valve chamber 88 into the main casing I5 may be prevented the valve stem 98 is provided with a projection II2 which engages a cap I I4 carried by a diaphragm I I8 extending across the end of the sealing chamber I88 and secured in engagement therewith by means of the threaded collar H8. The cap I I4 serves to reinforce the center portion of the diaphragm which receives the pressure of the operating parts.

As shown in Fig. 3, the pilot control valve assembly described is housed within part of the end casing 88 and is positioned to one side of the vertical axis of the main casing I5. That portion of'the end casing 58 which is adjacent the vertical axis of the main casing I5 is provided with a chamber I28 (Fig. 4) within which a thermoelectric assembly is adapted to be housed. This assembly includes a horseshoe electromagnet I22 seated on its base I24 in an end cap I 26 secured by screws I 21 to the end casing 58 and forming a closure for the opening I28. In order to secure the magnet I22 yieldably in position and prevent distortion thereof, a coil spring I 28 is held in position on the magnet base I24 by means of a magnet retainer I38 secured by means of the screws I32 to the end cap I28. A stem I34 extends between the legs of th magnet I22 and through the magnet retainer I38, there be ing an aperture I38 provided in the magnet base I24 to permit further extension of the stem during operation of the device. The stem carries an armature bar I38, abutting a flange I48 on the stem, and adapted to bridge the poles of the magnet I 22 in the usual manner. An armature stem spring I42 extends between the nut I48 and the magnet retainer I 38 and serves to urge the armature bar I38 away from the poles of the magnet I 22. In order to prevent the spring I42 from unseating the magnet from the end cap I 26, the spring I28 may be made considerably stronger than the spring I42.

The arms of the horseshoe electromagnet carry the coils I44 of a wire I48 which is connected by soldering or other suitable means to the head I48 of a terminal screw I58, the opposite end of the wire being secured to the magnet retainer I38. As shown in Fig. 6, the terminal screw I58 extends through the end cap 58 and emerges from the main housing I5 at a point behind the connection' for the pilot burner conduit I88. The terminal screw I58 is insulated from the body of the casing by the sleeve I52 and the terminal insulator I54.

A terminal sleeve I56 having a threaded end I58 is screwed into the end casing 58 around the insulating sleeve I52. A portion I59 of the insulating sleeve projects beyond the terminal sleeve and the terminal screw I58 projects still further. The projecting parts form terminals providing suitable electrical connection for the two elements, I88 and I82, of a thermocouple, these elements being separated at the terminals by means of the insulating washer I84.

The thermocouple may be supported by a bracket I88 in position to be heated by the pilot burner II8, thereby to establish an electric current to the coils I44 of suflicient strength to enersize the mag et I 22 and hold the armature bar j as sts as m contact with the ooierooos'tn reoruaiqst the force of the spring I42 provided that then:-

mature bar has been moved intocontact withfthe magnet in a manner -which w il l "now be :exf

plained. a a Formed in the end-casing "immediately above the chamber I20 for the thermoelectricassembly andon substantially the same vertical axis, is a smaller chamber I88 within which a reset button 7 10 I10 is slidably mounted. This reset button carries a reset stem I12 extending through anaperture inthe bottom wall of the chamber I88 and having a projecting end I14 extending into the main casing I adjacent the tapered opening'ot the valve seat 2 I. The reset stem "2 is provided with a collar I18 between the stem and its projection I14. A coil spring I18 acts between the reset button I and the end wall or the opening I88 to urge the button outwardly from the opening, this movement being limited by. the engagement of the collar 8 with the end wall. springwill cause return of the button I10 to the position shown in Fig. 4 after it hasbeen manually depressed and released.

The projection I14 cooperai s with the end of the shut-oil cook 23 to prevent manual actuation of the reset button I I0 except when the cock is in one position. The three positions of fullclosed, pilot and full-open with the position of the projection I14 are shown'in Figs. 10, 11 and 12, respectively. To this end, the cock is provided with a slot I80 which is so related to the arcuate groove 48, inlet nipple I1 and aperture 82 previously described, that when the dial is moved to the pilot position the slot will be aligned with the projection "401 the reset stem, as shown in Fig. 11.

This invent'on is particularly directed toward the provision of but a single valve for providing both thermostatic control of the main burner and safety control of the flow of fuel thereto should the "pilot burner become extinguished. Accordingly, the body of the main casing I5 is of hollow form below the portion carrying the plug cock 28 and is provided with a web I82 within which of fuel through the ports I92 in the valve seat to the outlet nipple I9, with which these ports are aligned. It will be observed that the valve assembly is axially aligned with the thermoelectric assembly with which it is operatively associated. V I w j The hollow valve stem I 88 contains a spring I04 which servesto urge a plunger I88 intocon 80 tact with a plug I98 closin'g'the inner end or the hollow valve stem. I The "reduced end ofthe plunger I98 projects through the plug and is adapted to engage and be qperated by a clicker mechanism comprised of a pair of opposed ful- 08 crum levers 200, fulcrum button 202 and clicker disc 204,-all of which are housed within a recess 205 formed in the annular valve seat I84. 4 Thermostatic means for operating the valve vided and consists of'an element or the rod-and tube type. A tube 2080f material having a high coefilcient of expansion is securely mounted at its inner end on the casing I5. The rod 208 or the 8 2881s recessed for Thus the mg a'lowooeliicient or the tube 288 one is; threadedlyf {at its outer end with a plug 2 I8 anchored thefouter end 01' the tube 288." The inner n oifthe rod w a nii o ient secured in positionbyfmeans ora p1 H cap 2I4' engages a-sealing 2 Iflsec redfinfa recess m in thecasins n by t val seat up and having its inner portion urgedi ofenga'ge mentlwith a thrust member '2'I8'byjthecap'inem ber24. As is well known, the differential in the expansion of the rod and tube under the influence of the heat '01 the water in which the device is mounted causes the rod to actuate the thrust member 2 to operate the clicker disc 204 which, in turn; operates the fulcrum button 202 and the opposed fulcrum levers -200. The levers 200 strike the plunger I88 which actuates the valve member I80 to open position, it being noted that the spring I84 is not compressed at this time as will be apparent hereinafter. Suitable means for mounting the control in the water heater or other appliance are provided by the elongated boss 220 projecting from the casing around the rod and tube element. The temperature at which the valve I80 will be operated may be adjusted by means of a manually operated lever 222 attached to the rod 288 by means of the set screw 224. The lever carries a pointer 228 for cooperationwith indicia 228 on thecasing. Movement or the lever in a vertical direction will serve to rotate the rod 288 and screw this rod further in or out of the plug 210 to change theexpansion differential. I

Movement of the valve I80 toward and away from its seat by the thermostatic ,device is governed by the condition of the thermoelectric mechanism previously described. Such governing action is eiiected by the provision '01 valve operating mechanism fcr the thermoelectric assembly which will now b described. The armature stem I84 is provided beyond the armature bar I88 with an extension having a threaded end 280. Mounted on the end 280 is an abutment member 282 having an annular recess 284 intermediate its ends. The abutment member 282 is suitably grooved to receive one end or a spring 288, the other end or which engages with the valve I80 urging it toward its seat.

The threaded extension 280- of thefannature stem also carries a collar 288 slidabiy' mounted within a guide disc 248 which, togetherwith a flexible sealing disc 242 carried on the stem. is securely retained in position across the end of the chamber I20 by means or the threaded collar 244. As will be apparent; the function of the sealing disc 242 is to prevent the entrance of fuel into the magnet chamber I20, while ,at the same with the'poles of the magnet I22.

Extending betweenythe projecting ehd I14 of bar toward and away .fromattracted position the reset stem and the recess 2'841 ih' ;the.abut-" ment member 282 'is a"pivotedflever 248.1 As

shown in Fig. 5, this lever is pivotally mounted intermediate its ends on aQpin-"ZABTIcarried by.

I spaced lugs 250 onftheinnerff'ace of'theendfcase stem extension I14 "is curved to slidably engage the extension I14" for this purpose.

end of the lever isalso slotted to extend around thermo-responsive unit, which is of material havthe recessed p tion 184 of the abutment 282 and time premitting freemovement ofthe armature ing as. The one or the lever adjaentjthefresetf I through the clicker disc mechanism is pro-'- 70 is similarly curved for slidable engagement with the walls of the recess 234. The lever 240 is further provided on one side with a radially extending arm 254 which is adapted to engage at its outer end with the cap member I I4.

To operate the control from the o position on the dial, as shown in Fig. '7, the dial is first rotated to the pilot position. Until this position is reached, no gas can pass the shut-oil? cock and both the pilot and the main burner'control valves are in closed position.

In the pilot position, as shown in Fig. 8, the fuel may flow from the inlet nipple I! by way of the arcuate groove 46 to the pilot passage 52 and.

thence to the pilot control valve 88which, as stated, is in the closed position. At this time the slot I30 in the lower portion of the shut-oi! cock 23 is in alignment with the extension I I4 of the reset stem I12. The reset button I is then manually actuated to depress the stem I12 and cause the extension I14 to enter the slot I80, as shown in dotted lines in Fig. 11. When the reset button is thus operated, the collar I16 on the stem I12 engages the curved end of the lever 246 and moves it in a clockwise direction, as viewed in Fig. 4, around the pin 246 as the fulcrum.

While the reset button is thus being actuated, the pilot control valve 88 is moved oil its seat by the engagement of the lateral arm 254 with the cap II4 on the end of the valve stem. Hence, gas is allowed to flow past the pilot control valve 88 and through the passages I02 and I04 to the pilot burner H0. The pilot burner may then be lighted and the flame size adjusted by operation of the adjusting screw I6. Due to the central pivoting of the lever 246 the lower end thereof will move in the opposite or clockwise direction when reset button I10 is depressed. Thus the lower end of the lever 246 acts against the lefthand wall of the recess 234, as viewed in Fig. 4, and forces the armature bar I36 against the pole faces of the magnet I22. The flame from the pilot burner impinges upon theend of the thermocouple which is connected in series with the coil I44 of the electromagnet I22.

In a short time the thermocouple generates sufficient current to energize the magnet and maintain the armature bar I38 in contact with the pole faces thereof. The reset button may then be released but the lever 246 remains in' pivoted position being maintained by the recess 234 in such position. Consequently, the lateral arm 254 continues to hold the pilot control valve 86 in open position and the abutment 232 remains stationary and spaced from the valve member I90. The position of the parts is as shown in Fig. 4, where the control device is in the operating position and the valve I90 free to be moved on its seat by the thermostatic control to permit flow of gas in the main burner.

To cause gas to flow to the main burner, the dial must be moved to the on" position, as shown in Fig. 4 and Fig. 9, permitting gas to flow from the inlet nipple I'I through the port 21 of the gas cock into the main body of the casing I5. In this position it will be observed that the groove 50 permits gas to flow to the pilot burner by connecting groove 48 with the inlet II. The indicator lever 222 may be set to the desired temperature indicated on the casing and the control will then be in complete operation.

As previously described in part the rod 208 of the thermostatic means will actuate the valve I90 with a snap action through the clicker mechanism provided. The movement of the plunger.

provided to, permit the fulcrum levers to move under thermostatic operation when the valve is being held closed by the safety mechanism.

In the event that the pilot burner is extinguished, the thermocouple ceases to generate cur- --rent, causing deenergization of the electromagnet and movement of the armature bar I36 away from the pole faces. Such movement of the armature bar is caused by the spring I42 which urges the abutment 232 toward the ,valve member I90. If the thermostatic mechanism is operating at this time to hold the valve I in open position, movement of. the abutment 232 will serve to close it. Such action is due to the spring I42 on the armature stem being stronger than the spring I94 in the valve stem. and thus overcoming it to move the valve I90 to closed position. During this movement of t e abutment 232 toward the right, as viewed in g. 4, the lever 246 is rotated on its pivot 240 in a counter-clockwise direction. The laterally extending arm 254 moves away from the cap II4 on the pilot control valve and the spring 92 for this valve moves it to closed position. Thus, when the pilot burner is extinguished ,for any reason the safety mechanism operates to close both the main control valve I90 and the pilot control valve 60, giving a complete shut-oil.

It .will be apparent that if an attempt were made to set the safety mechanism in any other than the correct way, as outlined hereinbefore, the construction of the control would prevent such operation from being carried out. The reset button I10 cannot be depressed if the dial is in any position other than the pilot" position. The parts are constructed and arranged so that the end of the reset stem extension "4 will strike the flange on the bottom of the shut-oil cook 23 before the collar I16 on the stem can engage the upper end of the lever 246. Thus, neither the main control valve nor the pilot control valve can be opened with the dial in any other than the pilot position.

It will be appreciated that the valve I90 is operated by the thermostatic mechanism under normal conditions but this mode of operation is supplanted by that of the electric control whenever conditions demand. If the thermostatic control, is holding the valve I90 oil" its seat and the safety mechanism comes into operation, the thermoelectric control overcomes the action of the thermostatic control, causing closure of both the main and pilot valves as described. Thus, the thermoelectric control is, in effect, a governor for the thermostatic control which normally operates the valve controlling fuel flow to the burner.

In controls where two or more valves are used in place of the single valve described and shown herein, the thermostatic valve is usually in constant operation but the safety valve is called upon to function only infrequently. It is apparent that unless abnormal conditions arise the safety valve has no occasion to operate. As this safety valve usually remains stationary for long periods-of time it becomes incapable of functioning efliciently when called upon to do so. An infrequently operated valve is subject to gumming due to the drying of lubricants and also to dirt from the gas being deposited on the seating surfaces.

Such condition of the safety valveawould not be discovered until the leakage became apparent. In the device described and. shown herein, the single valveis in oonst'antoperatlon as a thermostatic valve and, when the thermoelectric safety device becomes operative, it acts upon this valve Closure of this'valve by the safety control is readily accomplished due to the absence of dirt on the seating surfaces and the operative condition in which thevalve has been retained. It may be noted that the continual opening and closing of such a valve will tend to make it self-cleaning.

The embodiment of the invention herein shown and described is to be regarded as illustrative only, and it is to be understood that various modifications and changes may be made within the scope of the appended claims without departing from the spirit'of this invention.

We claim:

1. In asafety control for gaseous fuel burners, the combination of a main fuel valve movable between positions for controlling supp y of fuel to the burner, a control valve positioned normal to said'main valve for intercepting the supply of fuel to the burner, electromagnetic means in axial alignment with said control valve and adapted to govern the operation thereof, manually actuable means extending substantially parallel with the axis of said control valve and into the path of movement of said main valve to set said electromagnetic means for'goveming operation, said manually actuable means being operable in only one position of said main valve, and a pivoted member extending between said electromagnetic and manually'actuable means for transmitting movements of one to the other. i u

2. In a safety control for gaseous fuel burners, the combination of a main fuel valve, a thermally operated control valve intercepting the supply of fuel, a pilot burner having communication with said mainfuel valve, means responsive to,

re, movable to s at lamina es tuable for simultaneouelymoving said at,- mature and operating said pilot burnermeans for overcoming the biasing means for the main controlling means and operating sai means to permit fuel supply to the mainburnenand means associated with said armature and movable therewith into and out of operative engagement with said main controlling means for permitting\op'- eration of said main controlling means to supply fuel to the main burner onlywhen said armature is in attracted position.

5. In a safety control for gaseousfuel burners having main and pilot burnersjthe combination of a main fuel valve, a-main control valve means permitting operation of said maincon trol valve to supply fuel to said main burner only when said armature is in attracted position, and means associated with said main fuel valve permitting operation of said manually actuable means only when said main valve isin one position.

6. In a safety control for gaseous fuel burners having main and pilot burners, the combination of a main fuel valve, a thermally Operated valve intercepting the supply of fuel to the main burner, a pilot burner control valve intercepting the supply of fuel to the pilot burner, thermoelectric means energizable by said pilot burner and having an armature movable to attracted position,

the presence of a flame at said pilot burner for governing the operation of said control valve, manually actuable means for setting said flame responsive means for governing operation, means for preventing operation of said manually actuable ineans when said main fuel valve is in open position, and manually actuable means to set the temperature at which said control valve will be operated. n

3. In a safety control for gaseous fuel bumers, the combination of a main fuel valve,a thermally operatedcontrol valve intercepting the supply of fuel to theburner, thermoelectric means adapted to govern the operation of said control valve, manually actuable means to set said thermoelectric means for governing operation, means for preventing operation of said'manually actuablemeans when said main valve is in open position, and manually actuable means to set the temperature at which said control valve will be operated.

4. In a safety control for gaseous fuel burners having main and pilot burners, the combination of a main fuel valve Governing the supply of fuel to both the main and pilot burners, means for controlling the supply of fuel from the main valve to the main burner, means for controlling the supply of fuel from the main valve to the pilot burner, blasingmeans for each controlling means urging the same to a position where fuel supply is prevented, thermoelectric means energizable by said pilot burner and having an armaply of fuel to the main manually actuable means for simultaneously moving said armature and operating said pilot control valve. means permitting operationof said thermally operated valve tofsupply fuel tosaid main burner only when said armatureisin'attracted position, and means associated with said main fuel valve permitting ually actuable means only when said main fuel valve is in one position.

7. In a safety control for Gaseous fuel burners having main and pilot burners, the combination of a main fuel valve having a pilot position, a thermally operated valve intercepting the supburner, a pilot burner control valve intercepting the supDLv of fuel from said main fuel valve to the pilot burner, thermoelectric means eneraiza le by 1d Pilot burner. an armature for said thermoelectric means movable between free and attracted positions, means extending between said, armature and said thermally operated valve to retain said valve in a closed position whensaid armature is free, manually actuable means for simultaneously move ing said armature to attracted position and op erating said pilot control valve to open position, and means associated with said main fuel valve permitting operation of said manually actuable means only when said main fuel valve is in pilot Position.

8. In a safety control for gaseous fuel burners having main and pilot burners, the combination of a main control valve for the main burner, a pilot control valve for the pilot burner, biasing means for each valve urging the'same to closed position, thermally responsive means for overcoming the main valve biasing means and actu-' ating said valve to open position, spring means operation of said maninterposed between said thermally responsive means and said main valve, safety means operable in opposition to said thermally responsive means and in cooperation with said biasing means upon the main valve to compress said spring and reverse the position of said main valve from open to closed, means for opening the pilot control valve and actuating the safety means to a position permitting the thermally -responsive means to actuate the main valve, and means responsive to the presence of a flame at the pilot burner for holding the last said means in said position.

9. In a fuel control device, the combination of a casing forming a conduit supplying fuel to a main burner, a pilot burner having a fuel supply connection separate from the conduit, a valve mounted in the casing for controlling the fiow of fuel in the conduit, snap-acting means biasing said valve to a position where passage of fuel to the main burner "is prevented, thermostat means associated with the snap-acting means and responsive to heat fluctuations caused by the main burner for reversing the position of said snap-acting means and holding the valve in a position where passage of fuel to the main bumer is permitted, and separate valve closing means responsive to absence of heat from the pilot bumer to overpower the thermostat means and reestablish the biased position of the valve, said means comprising a plunger cooperable with the snap-acting means for moving the valve to biased position, a magnet for holding the plunger in position to permit reversal of the position of the snap-acting means, and a thermocouple exposed to the heat of the pilot burner for energizing the magnet.

10. In a safety control for gaseous fuel bumers, the combination of means movable between positions for controlling the supply of fuel to the burner, actuating means for said fuel controlling means positioned for operation on one side thereof, means biasing said fuel controllin means to a first position where suppl of fuel to'the burner is prevented, yieldable means intersaid first to a second position where fuel supply is permitted, and thermally responsive means adapted to exert sufficient force upon said controlling means from the opposite side to said actuating means to cause return or said control ling means from said second to said first position-to cut off the fuel supp y to the burner, said yieldable means being adapted to absorb the force of the first said thermally responsive means upon said return operation.

11.. A safety control for fuel burners having main and pilot burners, comprising a body memthereto for operation from one side of said seat,

yieldable means interposed between said actuating means and valve member and operative to vary said relation, thermally operable means responsive to the main burner for causing operation of said actuating means to disengage said valve from its seat while said yieldable means remains inoperative to vary said relation, and means responsive to the absence of heat at pilot burner adapted for operative engagement with said valve member from the opposite side of said seat for returning said valve member into engagement with said seat, said yieldable means becoming operative to vary said relation thereby permitting said valve member to return irrespective of operation of said actuating means tending to continue said disengagement thereof.

12. In a.safety control for fuel burners having main and pilot burners, comprising a body member having a passage for fuel, a valve seat in said body defining the inlet and outlet sides of said passage, a valve member engageable with said seat for controlling flow of fuel from the passage to'the main burner, actuating means for said valve member positioned in spaced relation thereto for operation from one side of said seat, means biasing said valve member toward said valve seat and operable from the opposite side of said seat relative to said actuating means, yieldable means interposed between said valve member and actuating means and having a stronger biasthan said biasing means, said yieldable means being operative to vary said relation,

means thermally responsive to operation of the main burner operatively engaging said actuating means to exert a force thereon for overcoming said biasing means and disengaging said valve member from said seat, said yieldable means remaining inoperative to vary said relation during said disengaging operation, and means thermally WILBUR F. JACKSON. THOMAS H. JEFFERB.

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