US2443892A

US2443892A - Safety control and ignition apparatus for gaseous fuel burners

Info

Publication number: US2443892A
Application number: US617703A
Authority: US
Inventors: Michael J Caparone
Original assignee: Robertshaw Fulton Controls Co
Current assignee: Robertshaw Controls Co
Priority date: 1945-09-21
Filing date: 1945-09-21
Publication date: 1948-06-22
Anticipated expiration: 1965-06-22

Description

June 22, 1948. M. J. CAPARONE I 2,443,892

' SAFETY CONTROL AND IGNITION APPARATUS OR GASEOUS FUEL BURNERS Filed Sept. 21, 1945 3 Sheets-Sheet 1 INVENTOR (07101051. d. Gamma/b.

5 ATTORNEY M. SAFETY CONTROL AND IGNITION APPARATUS June 22, 1948. J. cAPARoNE' FOR GASEOUS FUEL BURNERS 3 Sheets-Sheet 2 Filed Sept. 21, 1945 INVENTOR (aka-H651. J. Cameo/vs.

x214 .%w44- ATTORNEY June 22, 1948. M. J. CAPARONE 2,443,892

SAFETY CONTROL AND IGNITION APPARATUS FOR GASEOUS FUEL BURNERS Filed Sept. 21, 1945 3 Sheets-Sheet 3 imnmu INVENTOR 071mm; JCJMAONE.

, ATTORNEY um 'rsosmrss' PATENT OFFICE h SAFETY CONTROL AND IGNITION APPA- BATUS FOR GASEOUS FUEL BURNERS Michael J. Caparone, Pasadena, Calif., assignor to Robertshaw-Fulton Controls Company, a

corporation of Delaware 1 Application September 21, 1945, Serial No. 617,163

20 Claims. (Cl. 158-1171) This invention relates to safety control and ignition apparatus for gaseous fuel burners and, a

more particularly, to thermomagnetic controls Fig.3 is a plan view of a thermomagnetic control valve illustrated schematically in Fig. 2;

Fig. 4 is a section taken on the line Iv -IV- therefor. of Fig. 3; r r

Apparatus of this general character ha b n 5 Fig. 5 isa section taken on the line V-V of subject to the disadvantage of requiring manual and effort tov reset the thermomagnetic control device in operating position due tothe relatively weak thermoelectric current available for holding purposes only. It has been proposed to utilize automatic resetting devices energized from sources extraneous of the apparatus itself, but

such energy is not always available or its use is undesirable.

The thergnomagnetic system of safetycontrol flnds a wide field of usefulness in domestic cooking ranges where control of the oven burner is desired; It is-apparent, however, that the elimination of commercial sources of electrical energy also deprives the system of a convenient means v o'f' j automatic ignition for the oven burner by a resistance coil or spark. Nevertheless, as the toplburners of ranges are usually ignited from a constant burning top pilot burner, the inj n e vof the objects of this invention is to utilize th resetting operation as a means for effecting tion of the oven burner.

e er object of the invention is to automatically discontinue the flow of fuel for igniting purposes after ignition has occurred.

"Another object of the invention is to control the entire safety and ignition apparatus by selfcontained thermoelectric means.

Another object of the invention-is to reduce the manual effort required during the resetting operation to a minimum.

Another object of the invention is to prevent flow of fuel to the oven burner until safety conditions have been established and to discontinue such flow at any time that such conditions do not exist.

Other objects and advantages will become apparent from the following description taken in connection with the accompanying drawings. wherein:

Fig. 1 is a schematic view partly in section. of a safety control and ignition apparatus for gaseous; fuel burners embodying the present invention;

Fig. 2 is a similar view of another embodiment of the invention; r

flow of fuel in the main fuel pipe I8 is under control of a main fuel cock 18. If desired, the main fuel cook 18 may embody thermostatic control meansof any known form responsive to the oven temperature forcontrolling the flow of fuel in the main fuel pipe l6.

The main burner I0 is adapted to be ignited from a constant burning top pilot burner 20' which may. be supplied with fuel from the main fuel pipe i6 anterior of the main fuel cool: It. A flash pilot burner 22 is located in proximity of the main burner I0 and is supplied with fuel by a pipe 24 connected to an auxiliary outlet 25 in the control device I. Aflash-tube 2tv extends between the top pilot burner" and the flash pilot burner 22 for causing ignition of the latter. If desired, an ignition pilot burner 28 may also be located in proximity of both the main burner Ill and the flash pilot burner 22 and be supplied with fuel by a pipe 30 connected to a by-pass 32 controlled by the main fuel cock l8 in order that fuel will be supplied to the ignition pilot burner "28 when the thermostat has operated to discontinue flow of fuel to the main burner i0. i i a p The control device [4, as shown schematically in Fig. 1, includes a valve seat 34 having a safety shut-off valve member 38 biased by a spring 31 into engagement with one side thereof for controlling flow of fuel between the pipes 18 and I2. The valve member 36 is connected by a minals 45. 41 to the terminals of a thermocouple 48 located to be heated by a flame at the main burner ill and the ignition pilot burner 22. The thermocouple 42 forms a thermo-electric generator for supplying energy to the electromagnet comprising coil 42, magnet 40 and armature 28 and rendering the same eilective for retaining the valve member It disengaged from the valve seat 24.

The armature 22 is moved into engagement with the pole faces of the magnet 40 by a manually operable resetting means comprising a reset stem 50 extending coaxial with the valve member I from adjacent the side of the valve seat 24 opposite that engaged by the valve member 26.

' The reset stem 50 is spaced from the valve member '2 when the latter is seated. The stem 50 projects exteriorly of the control device l4 and terminates in push-button I2 to which manual pressure may be applied for moving the reset stem 50 into operative engagement with the valve member 3'. The projecting portion of the reset stem 50 carries an armature 54 which is movable into attracted relation with the pole faces of a horseshoe magnet 56. A coil spring il located between the armature b4 and the magnet serves to bias the reset stem 50 outwardly of the control device l4 and the armature 54 away from the pole faces of the magnet 56.

One leg of the magnet 56 is provided with a coil '0 which is connected at its opposite ends to terminals 6i and 63 respectively and by

wires

62 and 64 from terminals ii, 63 to the terminals of athermocouple 86 located to be heated by a flame at the top pilot burner 20. The thermocouple 66 forms a thermoelectric generator for supplying energy to the electromagnet comprising coil 60, magnet 58 and armature.

The other leg of the magnet 56 is provided with a trip coil 61 which is connected at opposite ends to terminals 69 and II respectively and in parallel circuit with the coil 42 by a wire 12 from terminal H to terminal 45 and a wire 13 from terminal 69 to terminal 41. The magnetic flux produced in magnet 56 upon energization of the trip coil 61 is opposed to that produced in this magnet by energization of the coil 60 and will cause release of the armature 54 from attracted position.

. I 4 Iv sired. The flow interrupting means comprises closure disc ll yieldably mounted on the reset stem 60 adjacent the valve seat 24 for operative engagement with the side thereof opposite the The control device It also includes an auxiliary valve 68 which is coopera-ble with a valve seat 10 formed in the control device I4 on the inlet side of the valve seat 34. Communication between the pipe 24 for th flash pilot burner 22 and the main fuel pipe i6 is provided by the outlet 25 in the control device i4 when the valve member 68 is disengaged from its seat. A spring I4 positioned in the outlet 25 between the auxiliary valve member 88 and a suitable abutment serves to bias the valve member 68 toward its seat Ill. The auxiliary valve member 68 may be in the form of a ball and the bias of the spring 14 holding the ball to its seat it is overcome by force exerted directly on valve member 28 when the latter is disengaged from the valve seat 24 during the resetting operation.

The alternative embodiment shown in Fig. 2 of the drawings contains many parts which have been described in connection with the embodiments shown in Fig. 1. Accordingly. similar reference numerals have been applied thereto and further description is deemed unnecessary. The essential distinction between the embodiments is that in Fig. 2 the reset stem It has mounted thereon, between the push-button l2 and the armature 64, a movable member carrying a contact element it which is adapted to operatively engage a relatively fixed contact element 22 during the resetting operation. As shown schematically in Fig. 2 the contact element it is connected to a terminal 81 and the contact element 42 is connected to the terminal 6i. The engagement between contacts 8' and 48 serves to close a circuit for a coil mounted on the other leg of the horseshoe magnet 40, this coil being shown as connected at opposite ends to terminals 4| and II respectively and in parallel with the coil It of magnet 56 by wires 92 and 94 extending from the terminals 9|, 92 to the terminal 62 and the terminal 81 respectively.

In the operation of the apparatus shown in Figs. 1 and 2. the main fuel cock I2 is first turned to the "on" position permitting fuel to flow to the control device i4 through the main fuel pipe it and also to the ignition pilot burner 22 through the fuel pipe 30. As the safety shut-oi! valve member 26 is biased by spring 21- into engagement with the seat 24, the flow of fuel through pipe I! to the main burner i0 is prevented. Also, as the auxiliary valve 68 is biased by spring ll into engagement with the seat l0. the flow of fuel through the pipe 24' to the flash pilot burner 22 is prevented. It may be assumed, however, that fuel is flowing to the top pilot burner 20 and that this burner is producing a flame.

The push-button 52 is now depressed and the bias of the spring 58 is, overcome to seat the closure disc I8 on the valve seat 34. Further movement of the reset stem 50, which can occur due to the yieldable mounting of the closure disc 18, is effective for engaging this stem with the valve member 36. The resetting operation so accomplished causes the bias of spring 31 to be overcome and the valve member 26 to become disengaged from the valve seat 34. Simultaneously, the armatures 28 and 54 are moved into attracted relation with the pole faces of the magnets 40 and 56 respectively.

As the first thermoelectric generator comprising thermocouple is being heated by the flame from the top pilot burner 20, there is suflicient current generated and conducted through the described circuit to retain the armature 64 in engagement with the pole faces of the magnet 56 with which the coil 60 is associated. It will further be observed that in the case of the embodiment shown in Fig. 2 the concurrent closure of the

contact elements

88 and 88 by operation of reset stem 50 will serve to close the described circuit of the coil 90 and energize the associated electromagnet suiilciently to cause the armature 28 thereof to be retained in attracted position.

The push-button 52 may now be released withv setstem 88' or associated parts due to the energiration of the electro'magnet or electromagnets'.

- It will be appreciated that this manual operation of the reset stem 88 is of short duration and no extended manual effort is required to eflect the outlet 28 and fuel pipe 28 to the flash pilot burner '22. The fuel from the flash pilot burner 22 is conducted by the flash-tube 28 to the top pilot burner 28 where it is ignited and the flame is then conducted by the flash-tube 28 to the flash pilot bumerf22 to produce a flame at this burner. The fuel issuing from the ignition pilot burner 28, disclosed in this embodiment of the invention, is now ignited bythe flame of the flash pilot burner 22. The second thermoelectric generator comprising thermocouple 88. which is positioned in proximity of the main burner I8, now becomes sumciently heated by the flame from the ignition pilot burner 28 to generate a current which is conducted through the described circuits for energizing the coil 82 and the trip coil 81 associated with

themagnets

88 and 88. respectively. vSince the magnetic flux produced in the magnet 88 by the trip coil 81 is opposed to that produced in this magnet by the coil 88, then the armature 88 is released. It is apparent, therefore, that one function of the second thermoelectric generator is for neutralizing the ens rgy supplied to the magnet 88 by the flrst thermoelectric generator and ran.- dering the same ineffective to retain the arma-v ture 88.

At the same time, however, that the trip coil 81 is energized, the coil 42 associated with the magnet 88 also becomes energized by the current supplied from the thermocouple 88. Thus.

the armature 38 is retained in engagement with the magnet 48 and the valve member 88 is held ,in the open position. The reset stem 88 is retracted under bias of the spring 58 when armature 88 is released so that the closure disc 18 becomes disengaged from the valve seat 88 while the auxiliary valve 88 ceases to be held open by the cup-shaped member I8. Thus, fuel may flow from the main fuel pipe I8 through thepipe I2 to the main burner I8 where it is ignited by the flame from the ignition pilot burner 28. The flow of fuel in the pipe 28 is cut off by closure of the auxiliary valve 88 and the flash pilot burner 22 ceases to produce a flame.

It will be noted that the switch comprising

contact elements

88 and 88, as disclosed in connection with the embodiment shown in Fig. 2, becomes opened when the armature 58 is released by operation of the trip coil 81. Hence, the .coil 88 associated with the magnet 88 is no longer energized but the armature 38 will be retained in the attracted position due to the energization of the 001182 of the magnet 48 by the thermocouple 88. Thus, in bothembodiments the valve member 38 controlling flow of fuel to main burner i8 will be held open by itsassoassassin 6 In the event that an attempt is made to start the system when-the toppilot burner 2 is burning. then the thermocouple." will be unheated and the coil 88 :(Fig. 1) and the

coils

88 and 88 ,(ll'ig. 2) will be deenergized. Thus, when the push-button "is depressedneither'of the armatures 84 mi- 88 will be retained in attracted position and consequently the valve members 88 and 88' will close when the push-button is released.

' If, however. the top pilot burner is lighted and the system is placed incperation by opening the ,main fuel cock I8 and depressing the push-button 82 but no flame is produced by the flash pilot burner 22, then the ignition pilot burner 28 will not become ignited. Hence, the trip coil 81 and the coil 82 associated with the

magnets

88 and 88, respectively, wili not become energized. Both of the

armatures

88 and 88 will be retained by theirrespective magnets and valve member 88' will remain in the open position with closure disc 18 in position to interrupt the flow of fuel in the fuel pipe I2 to the main burner-18., Since the auxiliary valve member 88 is being held away from its seat by the cup-shaped member "there will be an escape of a small amount of unburned .fuel from the flash pilot burner 22 and from the tion of the main burner pilot isnot required.

Such modifications are intended to be included inthe scope of the invention without departing from the spirit thereof.

Referring now more particularly to Figs. 3, 4. 5 and 6, the control device I8 may take the form shown in detail therein. Where possible, similar reference numerals have been used to denote parts corresponding to those described in the schematic forms of Figs. 1 and 2. In this embodiment the control device comprises a casin I88 provided with a chamber I82 therein having an inlet opening I1 and an outlet opening l8 intermediate the ends thereof and disposed on opposite sides. Passage of fuel between the inlet I I and the outlet I8 for a mainv burner is controlled by a safety shut-oil. valve member 88 which is cooperable with a valve seat 88 disposed between the inlet and outlet I8. An auxiliary outlet 25 is located in the chamber I82 on the inlet side of the valve seat Y88 and is provided with suitable connection Ill for conveying fuel to a pilot burner. The auxiliary outlet 28 is controlled by an auxiliary valve 88 in the form of a ball movable in a path normal to the safety valve member 38 and which is biased into enmoves into operativeengagement with thesafety valve member 38 for opening the same when the reset stem 88 is moved toward the valve seat 88.

The reset stem extension I28 carries a closure disc I8 which is yieldably urged toward an cuauaaos largement I88 on the extension I28 by a spring I82 which engages at its opposite end with a cupshaped element 18 mounted on the extension I28 for slidable movement therewith. The cupshaped element I8 engages the walls of the chamber-I8 and is slidable axially of the safety valve 88 into operative eng'agement with the auxiliary valve 88 for opening the'same against the bias of the spring I4. The closure disc I8 serves to interrupt the flow of fuel between the inlet II and the outlet I8 by engaging the valve seat 84 on the side opposite the safety valve member 88 when the latter is disengaged from the seat by operation of the reset stem 58.

The cup-shaped element I8 is retained against movement relative to the extension I28 by a nut I88 thereon which has its opposite face provided with an annular lip for engagement with a yieldable ring I38 in the adjacent face of the cap I22. A sealing device is provided for the chamber I82 beyond the cup-shaped element I8 to 'prevent leakage along the reset stem 58. This device comprises a sealing washer I81 on the reset stem and housed within a chamber I88 in the cap I22 under bias of a spring I48.

A first electromagnetic means is positioned on in an insulating sleeve I48 projecting from the cap member I22 around the magnet 58. The projecting end of the sleeve I48 carries a metal contact ring 88 for a purpose which will hereinafter be apparent. c

The other leg of the magnet 58 is provided with a coil58 (see Fig. having one end secured to a terminal 8I on the ring 88 and the other end secured to a terminal 88 on the sleeve I48 diametrically opposite the terminal II. An armature 54 is cooperable with the pole faces of the magnet 58 and is mounted upon the reset stem 58 abutting one side of a shoulder I5'I-thereon. The opposite side of the shoulder I5'l abuts a coil spring 58 extending along the reset stem 58 to the flexible element I43 and serving to bias the armature 54 away from the pole faces of the magnet 58. It may be noted that the armature spring 58 exerts a stronger bias than the spring I32 associated with the closure disc 18 so that the latter is also biased away from the valve seat 84.

The side of the armature 54 opposite the resetstem shoulder I51 is maintained in engagement with the inner face of a cup-shaped contact element 88 by the bias of a spring I82 which engages at one end with the element 88 and at its opposite end with a reset button 52. The reset button 52 projects from an end casing I58 which is mounted upon the insulating sleeve I48 and is secured to the cap I22 by means of screws I88 which also serve to hold the insulating sleeve I48 in position; The end casing I88 is provided with a flanged end for engagement with a flange I'I8 formed on the reset button 52 and serving to limit and is adapted when energized for retaining the safety valve in open position while rendering the first electromagnetic means ineffective for this purpose. In this embodiment, the second eiectromagnetic means comprises a horseshoe magnet 48 provided on one leg with a coil 43 and on connected to a terminal 48 and the opposite end of the coil 42 is connected to a terminal 41.

7 Both terminals are carried in spaced arrangement on an end plate I82 having an extension sleeve I84 secured to the casing I88 and forming a closure for a magnet housing I88 which engages the wallsof the chamber I82 and is provided with an end wall 4i. The coil 88 has-one end secured to a terminal 88 on the end cap I82 and the opposite end is secured to an insulated terminal 8| disposed axially of the end cap I82 said projecting through the base of the magnet 4 An armature 88 is provided for cooperation with the pole faces of the magnet 48 and is supported upon a connecting stem 88 which extends therefrom through the end wall 4I of the magnet housing I88 and serves to connect the armature 88 and valve member 88 together. A coil spring 81 operative between the end wall 4i of the magnet housing I88 and the safety valve 88 serves to bias the valve to closed position relative to the valve seat 84 and the armature 88 away from the pole faces of the magnet 48..

When the control device of the embodiment of Figs. 4, 5 and 6 is in the position shown in the drawing, then the main burner is receivingfuel and may be assumed to be in operation. when the safety control is in the off" position then the armature 38 of the second electromagnetic means will be disengaged from the pole faces of magnet 48 and the safety valve 38 will be in closed position relative to the valve seat 34.

The safety control device may be placed in operation by manually depressing the reset button 52 to move the armature 54 into engagement with the pole faces of the magnet 58 and also the armature 38 into engagement with the pole faces of the magnet 48. During this action, the re-.

set stem extension I28 engages the safety valve 38 and disengages it from the valve seat 84 immediately after the closure disc-18 has likewise been moved into engagement with the opposite side of the valve seat 34; The cup-shaped element I8 then moves slidably relative to the walls of the chamber I82 and exerts a force upon the auxiliary valve 88 to move it in a path normal to the axis of the safety 'valve 38 and away from its seat I8. The cup-shaped contact element 85 and the metal contact ring 88 are now brought into engagement and a circuit for one coil of each of the first and second electromagnetic means is provided asdescribed in connection with Fig. 2. Thus, the

coils

88 and 88 may be 52 is released due to energization of both

magnets

48 and 58.

If the trip coil 81 is now energized as by a thermocouple heated by a pilot burner, then the armature 54 will be released, the auxiliary valve 88 will close and the closure disc I8 will be disengaged from the valve seat 34. At the same time, the cup-shaped contact element 88 will become disengaged from the metal contact ring 88 to cause opening of the circuit to the coil 88.

auasoa 9 However. due to the continued energlzation of the coil 42 associated with the magnet ll, the armstui'e ll thereof is retained against thepole faces- 1 of the magnet II and the safety valve 38, re-

electromagnetic means as long as the pilot burner remains lighted as previously described. t

It willbe apparent that a self-contained system for 'safetycontrol and ignition of a domestic oven burner has been provided and that the conl p supply is prevented, an electro-responsive device for'contl'011in8 saidmovable means and includtroldevice ofFlgs. s-s "finds a peculiar held of a i net eflective for retainingsaid movable means in usefulness in connection with the flash-tube ignition and safety control system disclosed in Figs. 1 and-2. The cup-shaped contact 86 and contact ring 88 which are equivalent to the switching means comprising

contacts

86 and 88 of the Fig. 2' embodiment may be dispensed with embodiment. It is understood. therefore. that various changes may be made in the details and arrangement .of parts within the scope of the appendedclaims without departing from the spirit of this invention.

I claimr- '1. Safety control. apparatus for fuel burners having mainand pilot burners comprising, means movable. between positions for controlling the fuel supply'to-"the 'main burner and being normally biased to a position in which said fuel supply is prevented, an electro-responsive device for controlling said movable means and including a pair of electromagnets, a first thermoelectric generator adapted when heated by a flame at the pilot burner for supplying energy to at least one ofsaid electromagnets and rendering the same eflective for retaining said movable means in a position where fuel is supplied to the main burner,

and a second thermoelectric generator adapted when heated by a flame at the main burnerfor supplying energy to both the one and the other of said electromagnets, said second generator being arranged for rendering the other said electromagnet effective for retaining said movable means in the fuel supply position while rendering said one electromagnet ineffective.

2; Safety control apparatus for fuel burners having main and pilot burners comprising, means movable between positions for controlling the fuel supply to the main bumer and being normally biased to a position in which said fuel supply is prevented, an electro-responsive device for con-,

ing a pair of electromagnets having separate opcrating coils associated therewith. a first thermoelectric generator adapted when heated by a flame at the pilot burner for supplying energy to at leastone of'said coils and renderingits associated electromagnet eflectlve for retaining said movable means in a position where-fuel is supplied to themain'burner, a secondthermoelectrlc generator adapted when heated by a flame at the main burner, for supplying energypto another of said coils andrendering its associated electromagtheifuel supply position independently of the electromagnet associated with said one coil, and a trip coil operatively associated with the last saldelectromagnet and in circuit with said second thermoelectric generator for neutralizing the energy supplied to said one, coil andrendering its associated electromagnet ineffective.

4. Safety control apparatus for fuel burners having main and pilot burners comprising, means movable between positions for controlling the fuels'upply to the main burner and being normally biased to a position in which saidfuel supply is prevented, an electro-responsive device for controlling said movablemeans and including a pair of electromagnets having a plurality of separate operating coils associated therewith, means operative in one direction for transmitting movement between said electromagnets and movable means, a first thermoelectric generator adaptedwhen heated by a flame atthe pilot burner for supplying energyto two of said coils and rendering said pair of electromagnets effective for retaining said movable means in'a position where fuel is supplied to the main burner, switching means controlling thecircuitof one of said two coils and-being operable to closed position by operation of said movement. transmitting means in said'one direction thereof, a second thermoelectric generator adapted when heated by a flame atthe main burner for supplying energy to another of said coils and rendering one of said pair of electromagn'ets effective for retaining said movable means in the fuel supply position independently of the other said electromagnet, a trip coil operatively; associatedwith said other electromagnet and in circuit with said second theremoelectric generator for neutralizing the energy supplied to-the other one of said two coils and rendering said other electromagnet in 5. Safety control and ignition apparatus for fuel burners having main and a pair of pilot adapted when heated by a flame at the main burner for supplying energy to both the one and the otherof said electromagnets, said second generator being arranged for rendering the other said electromagnet effective for retaining said movable means in the fuel supply position while neutralizing the energy supplied to said one electromagnet and rendering the same ineffective.

3. Safety control apparatus for fuel burners having main and pilot burners comprising means movable between positions A for controlling the fuel supply to the main burner and being normally biased to apositlon in which said fuel burners comprising, means movable between posi tions for controlling the fuel supply to the main and one of the pilot burnersand being normally biased to a position in which said fuel supply is.

pilot burner for supplying energy to at least one of said electromagnets and rendering thesame effective for retaining said movable means in a position where fuel is supplied to both the main and said one pilot burner, and a second thermoe ectric generator adapted when heated by a dame at said one pilot burner for supplying energy to both the one and'the other of said electromagnets, said second generator being arranged for rendering the other said electromagnet effective for retaining said movable means in the fuel supply position while rendering ineffective.

6.Safety control and ignition apparatus for fuelburners having main and a pair of pilot burners comprising, means movable between positions for controlling the fuel supply to the-main and one of the pilot burners and being normally biased to'a position in which said fuel supply is prevented, an eleetro-responsive device for controlling saidmovable means'and including a pair of electromagnets. a first thermoelectric generator adapted when heated by a flame at the other pilot burner for supplying energyto at least one of said electromagnets and rendering the same effective for retaining said movable means in a position where fuel is supplied to both the main and said one pilot burner, means for conducting fuel between said pilot burners for causing ignition of said one pilot burner from the other, and a second thermoelectric generator adapted when heated by a flame at said one pilot burner for supplying energy to both the one and the other of said electromagnets, said second generator being arranged for rendering the said other electromagnet effective for retaining said movable means in the fuel supply position whilerendering said one electiomagnet ineffective. 7. Safety control and ignition apparatus for fuel burners having a main burner, an ignition pilot burner in proximity thereto, and a source of fuel supply, comprising means movable between positions for controlling the fuel supply from the source to the main burner and being normally biased to a position in which said fuel supply is prevented, an electro-responsive device for controlling said movable'means and including a pair of electromagnets. means operative in one direction for transmitting movement between said electromagnets and movable means, a first thermoelectric generator adapted when heated for supplying energy to at least one of said electromagnets and rendering the same effective for retaining said movable means in a position where fuel is supplied to the main burner, a second thermoelectric generator adapted when heated by a flame at the ignition pilot burner for supplying energy to both the one and the other of said electromagnets, said second generator being arranged for rendering the other said electromagnet effective for retaining said movable means in the fuel supply position while rendering said one electromagnet ineffective and causing operation of said movement transmitting means in another direction, a constant burning pilot burner located remote from said ignition pilot burner and connected to the source for heat- .ing said first thermoelectric generator, a flash pilot burner located in proximity to said ignition pilot burner and connected to the source, a flash tube extending between said constant burning pilot burner and said flash pilot burner for causing ignition of the latter, and means responsive to operation of said movement transmitting means in said other direction for discontinuing the fuel supply to said flash pilot burner.

8. Safety control and ignition apparatus for fuel burners having a main burner, a pilot burner in proximity thereto, and a source of fuel supply, comprising means movable between positions for controlling the fuel supply from the source t th said one electromagnet main burner and being normally biased to a position in which saidfuel'supply is prevented, reciprocable means having lost motion connection with said movable means and being manually 1 operable for moving said moving means between said positions, flow interrupting means responsive to said operation of said reciprocable means for preventing flow of fuel to the main burner, an electroresponsive device for controlling said movable means and including a pair of electromagnets, a first thermoelectric generator adapted when heated by a flame at the pilot burner for supplying energy to at least one off said electromagnets and rendering the same eflfective for retaining said movable means in'a position to which it has been moved by said reciprocable means, and a second thermoelectric generator adapted when heated by a flame at 'the main burner for supplying energy to both the one and the other of said electromagnets, said second generator being arranged for rendering the other said electromagnet efiective for retaining said movable means in said moved position while rendering said one electromagnet ineifective, said flow interrupting means being rendered ineffective by return of said reciprocable means to unoperative position.

9. Safety control and ignition apparatus for fuel burners having a main burner, an ignition pilot burner in proximity thereto, and a source of fuel supply, comprising means movable between positions for controlling the fuel supply from the source vto the main burner and being normally biased to a position in which said fuel supply is prevented, reciprocable means having lost motion connection with said movable means and being manually operable for moving said movable means between said positions, flow interrupting means responsive to said operation of said reciprocable means for preventing flow of fuel to the main burner, an electro-responsive device for controlling said movable means and including a pair of electromagnets, a first thermoelectric generator adapted when heated for supplying energy to at least one of said electromagnets and rendering the same effective for retainng said movable means in a position to which it has been moved by said reciprocable means, a second thermoelectric generator adapted when heated by a flame at the ignition pilot burner for supplying energy to both the one and .the other of said electromagnew, said second generator being arranged for rendering the other said electromagnet effective for retaining said movable means in said moved position while rendering said one electromagnet ineffective, said flow interrupting means being rendered ineffective by return of said reciprocable means to unoperated position, a constant burning pilot burner located remote from said ignition pilot burner and connected to the source for heating said first thermoelectric generator, a flash pilot burner located in proximity to said ignition pilot burner and connected to the source, a flash tube extending between said constant burning pilot burner and said flash pilot burner for causing ignition of main burner and having separate connection with said fuel supply pipe, a constant burning pilot burner positioned remote from said flash pilot burner, a flash tube extending between said pilot burners for conducting a flame therebetween,'a safety shut-off valve yieldingly urged closed for controlling flow of fuel to said main burner, means operable for opening said safety valve including electromagnetic means effective when energized for holding said safety valve open, a thermoelectric generator adapted to be heated by a flame produced by said means for igniting the main burner for energizing said electromagnetic means, an auxiliary valveyieldingly urged closed for controlling flow of fuel to said flash pilot burner. and means, responsive to operation of said means for opening said safety valve, for holding said auxiliary valve open.

11. Safety control and ignition apparatus for fuel burners comprising in combination, a main burner, a fuel supplypipe connected to the main bumer,.means for igniting said main burner ineluding a flash pilot burner in proximity of the I being normally biased to a closed position, an auxiliary valve in said casing for controlling passage of fuel from said inlet to a pilot burner, means biasing said auxiliary valve ,to closed position, electromagnetic means positioned in said casing and connected to said safety valve for holding the same in open position but being incapable of moving said safety valve to open position, a manually operable reset stem mounted in said casing and reciprocable into operative engagement with said safety valve for opening the same and resetting said electromagnetic means,

and means mounted on said stem for slidable movement in said easing into operative engagement with said auxiliary valve for opening the same during the resetting operation.

14. A safety control for gaseous fuel burners comprising a casin having a chamber therein, inlet and outlet openings communicating with said chamber and providing passage for fuel to a main fuel burner, a safety shut-off valve controlling flow of fuel between said openings and being normally biased to a closed position, an auxiliary valve in said casing movable in a path normal to said safety valve for controlling passage of fuel from said inlet to a pilot burner, means biasing said auxiliary valve to closed position, electromagnetic means positioned insaid main burner for energizing said electromagnetic means, an auxiliary valve yieldingly urged closed for controlling flow of fuel to said flash pilot burner, manually operable means for opening said safety valve, and means responsive to operation of said manually operable means for holding said auxiliary valve open.

12. Safety control and ignition apparatus for fuel burners comprising in combination, a main burner, a fuel supply pipe connected to the mainburner, means for igniting said main burner including a flash pilot burner in proximity of the main burner and having separate connection with said fuel supply pipe, a constant burning pilot burner positioned remote from said flash pilot burner, a flash tube extending between said pilot burners for conducting a flame therebetween, a safety shut-off valve yieldingly urged closed for controlling flow of fuel to said main burner, electromagnetic means having an armature connected to said safety valve, a thermoelectric'generator adapted to be heated by a flame produced by said means for igniting the main burner for energizing said electromagnetic means and holding said armature in attracted position and said safety valve open, a reset stem manually operable for placing said armature in attracted position and opening said safety valve, means carried by said stem for interrupting flow of fuel throughsaid main burner supply pipe during the resetting operation, an auxiliary valve yieldingly urged closed for controlling flow of fuel to said flash pilot burner, and means carried by said stem for actuating said auxiliary valve'to open position during said resetting operation.

13. A safety control for gaseous fuel burners comprising a casing having a chamber therein, inlet and outlet openings communicating with said chamber and providing passage for fuel to a main fuel burner, a safety shut-off valve controlling flow of fuel between said openings and casing coaxial with said safety valve and connected to said safety valve for holding the same in open position but being incapable of moving said safety valve to open position, a manually operable reset stem mounted in said casing and reciprocable axially of said safety valve into operative engagement with said safety valve for opening the same and resetting said electromagnetic means, and means mounted on said s em for slidable movement in said casing axially of said safety valve into operative engagement with said auxiliary valve for opening the same during the resetting Operation.

15. A safety control for gaseous fuel burners comprising a casing having a chamber therein, inlet and outlet openings communicating with said chamber and providing passage for .fuel to a main fuel burner, a safety shut-off valve controlling flow of fuel between said openings and being normally biased to a closed position, an auxiliary valve in said casing movable in a path normal to said safety valve for controlling passage of fuel from said inlet to a pilot burner, means biasing said auxiliary valve to closed position, electromagnetic means positioned in said casing coaxial with said safety valve and connected thereto for holding the same in open position but being incapableof moving said safety valve to open position, a manually operable reset stem mounted in said casing and having lost-motion connection with said safety valve, said reset stem being movable into operative engagement with said safety valve for opening the same and resetting said electromagnetic means, flow interrupting means mounted on said reset stem for preventing flow of fuel between said inlet and outlet openings tothe main burner, and means mounted on said stem for slidable movement in said casing axially of said safety valve intoopera tive engagement with said auxiliarvvalve for opening the same during the resetting operation.

16. A safety control fora gaseous fuel burner comprising a, casing having a chamber therein, inlet and outlet openings communicating with said chamber intermediate the ends thereof and providing passage for fuel to the burner, a safety s ut-off valve controlling flow of fuel between assassin said openings and being normally biased to a closed position, means operable for opening said safety valve and being normally biased to an inoperative position, said means including first electromagnetic means positioned in said casing on one side of said safety valve and adapted when energizedfor retaining said safety valve in open position, a second electromagnetic means positioned in said casing on the opposite side of said safety valve and adapted when energized for retaining said safety valve in open position, means for rendering said first electromagnetic means ineffective when said second electromagnetic means is energized, and means controlled by said first electromagnetic means for preventing passage of fuel between said inlet and outlet openings until said first electromagnetic means is rendered inefiective.

17. A safety control for a gaseous fuel burner comprising a casing having a chamber therein, inlet and outlet openings communicatinglwith said chamber intermediate the ends thereof and providing passage for fuel to the burner, a safety shut-off valve controlling flow of fuel between said openings and being normally biased to a closed position, means operable for opening said safety valve and being normally biased to an inoperative position, said means including first electromagnetic means positioned in said casing on one side ofsaid safety valve and including a magnet and coil adapted when energized for retaining said safety valve in open position, a

second electromagnetic means positioned in said casing on the opposite side of said safety valve and including amagnet and coil adapted when energized for retaining said safety valve in open position, a trip coil for the first said magnet for neutralizing the energy supplied to the first said coil when said second coil is energized, and means connected to the first said magnet for preventing passage of fuel between said inlet and outlet until said first coil is neutralized.

18. A safety control for a gaseous fuel burner having separate sources of electrical energy associated therewith, comprising a casing having a chamber therein, inlet and outlet openings communicating with said chamber intermediate the ends thereof and providing passage for fuel to the burner, a safety shut-off valve controlling flow of fuel between said openings and being normally biased to a closed position, means operable for opening said safety valve and being normally biased to an inoperative position, said means including first electromagnetic means positioned in said casing on one side of said safety valve and including a magnet and coil adapted to be energized from one source for retaining said safety valve in open position, a second electromagnetic means positioned in said casing on the opposite side of said safety valve and including a magnet and coil adapted to be energized from another source subsequent to energization of the first said coil for retaining said safety valve in open position, and a trip coil for the first said magnet adapted to be energized from said other source and connected in parallel with said secand coil for neutralizing the energy supplied to the first said coil simultaneously with the energization of said second coil.

19. A safety control for agaseous fuel burner,

having separate sources of electrical energy associated therewithicomprising a casing having a chamber therein, inlet and outlet openings communicating with said chamber intermediate the ends thereof and providing passage for fuel to ii the burner, a safety shut-off valve controlling fiow of fuel between said openings and being normally biased to a closed position, means operable for opening said safety valve and being normally biased to an inoperative position, said means including first electromagnetic means no sitioned in said casing on one side of said safety valve and including a. magnet and coil adapted to be energized from one source, a second electromagnetic means positioned in said casing on the opposite side of said safety valve and including a magnet and a pair of coils, one of said pair being adaptedto be energized from another source subsequent to energization of the first said coil for retaining said safety valve in open position, the other of said pair being connected in parallel with said first coil for enersization simultaneously therewith for retaining said safety valve in open position until said one coil of said pair is energized, a switch operable in said casing for controlling said parallel connection, and a. trip coilfor the first said magnet connected in parallel with said one coil of said pair for neutralizing the energy supplied to said first coil simultaneously with the energization of said one coil of said pair and operation of said switch to discontinue said parallel connection. l

20. A safety control for gaseous fuel burners having main and pilot burners and separate sources of thermoelectric energy associated therewith, comprlsing a casing having a. chamber therein, inlet and outlet openin s communicating with said chamber intermediate the ends thereof and providing, passage for fuel to the burner, a safety shut-off valve controlling flow of fuel between said openings and being normally biased to a closed position, a duct in said casing on the inlet side of said safety valve providing communication between said chamber and the pilot burner, first electromagnetic means positioned in said casing on one side of said safety valve and including a magnet and coil adapted to be energized from one source for retaining said safety valve in open position but being incapable of moving said safety valve to said position, manually operable reset means mounted in said casing and having lost motion connection with said safety valve, said reset means being normally biased to an inoperative position and being operable for resetting said first electromagnetic means while preventing fiow of fuel between said inlet and outlet, a second electromagnetic means positioned in said casing on the opposite side of said safety valve and including a magnet and coil adapted to be energized from another source responsive to a fiame at the pilot burner subsequent to energlzation of the first said coil for retaining said safety valve in open position, and a trip coil for the first said magnet adapted to be energized from said other source and connected in parallel with said second coil for neutralizing the energy supplied to the first said coil simultaneously with the energization of said second coil.

MICHAEL J. CAPARONE.

REFERENCES orrao The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,290,048 Hildebrecht July 14, 1942 2,340,234 Thornbery, et al. Jan. 25, 1944 2,351,277 Mantz June 13, 1944