US2319685A

US2319685A - Safety control fob gaseous fuel

Info

Publication number: US2319685A
Authority: US
Publication date: 1943-05-18
Anticipated expiration: 1960-05-18

Description

y 8, 1943 w. F. JACKSON ETAL 2,319 685 SAFETY CONTROL FOR GASEOUS FUEL BURNERS Filed May 14, 1941 3 Sheets-Sheet l Z22 222 INVENTOR.

W/L BUR l-fJqcxsozvg 1 TH as H.J'EFFEAS 62 "ATTORNEY May 18, 1943 w. F. JACKSON ETAL 2,319,685

SAFETY CONTROL FdR GASEOUS FUEL BURNERS Filed May 14, 1941 s sh eetssheet 2 I Q g: s

m s Q o u, g a. E v

INVENTOR. Wu. BUR E Jae/(solu- [H N/1.5 H-J FERS :3 W

ATTORNEY.

3 Sheets-Shet 5 w. F. JACKSON ETAL Filed May 14, 1941 WILBUR E Jhcmsoua/ THOHHS H. JFFER$ SAFE TY CONTROL FOR GASEOUS FUEL BURNERS May 18, 1943 III Patented May 18, 1943 SAFETY CONTROL FOR GASEOUS FUEL BURNERS Wilbur F. Jackson, Lynwood, and Thomas H. Jeflers, Los Angeles, Calii'., assignors to Grayson Heat Control, Ltd., Lynwood, Calif., a corporation of California Application May 14, 1941, Serial No. 393,397

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 passage and automatic opening of the main burner line only after the pilot burner is lighted. In normal operation fuel supply to the main burner is thermostatically regulated to maintain the water to be heated at a predetermined temperature. Should the flame of the pilot burner be extinguished for any reason, fuel supp y to both the main and pilot burners is shut ofi and no fuel can flow to the burner until the device has been manually reset and the pilot burner relighted. erator of the control to exert physical effort upon the device for a considerable period of time, usually against spring pressure before the Pilot burner can be relighted. This operation has naturally proved tedious and fatiguing on many occasions to the average user of domestic appliances.

An object of this invention is to facilitate the operation of resetting the safety control by Manual reset devices require the opeliminating push buttons and similar manually operated devices.

Another object of the invention is to render the resetting operation I entirely automatic.

Another object of the invention is to increase the safety features of such controls by reducing the number of Another object of tlie invention is to ensure complete and positive shut-off of the fuel supply to both main .and pilot burners whenever the pilot burner is extinguished.

Another object of the invention is to utilize common means for resetting the safety control and operating the pilot valve.

Another object of the invention is to permit operation of the safety control not only during main burner operation but also when the appliance is being operated on the pilot burner alone. e

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

7 4-4 of Fig. '7, looking in the direction indicated by the arrows;

Fig. 5 is a section taken on the line 5-5 of Fig. 7, looking in the direction indicated by the arrows;

Fig. 6 is a section taken on the line 66 of Fig. 7, looking in the direction indicated by the arrows;

Fig. '7 is a longitudinal sectional view;

Figs. 8 and 9 are geometrical developments of the seating surfaces of the main fuel valve;

- Fig. 10 is asection taken on the line ill-Ill of Fig. 3, looking in the direction indicated by the arrows:

Figs. 11, 12, 13 and 14 are partial sections taken on the line ll'-ll of Fig. 'l' and showin difierent positions of the main fuelvalve;

Figs. l5, l6, 1'! and 18 are partial sections taken along the line l5-l5 of Fig. '1 and showing different positions of the main fuel valve; and

Figs. 19, 20, 21 and 22 are partial sectional views taken along the line l9-l9 of Fig. 7, showing the relative positions of the resetting device when the main fuel valve is in the positions of Figs. 11 to 14, respectively.

Referring more particularly to the drawings, the control comprises a casing l5 provided at one end with a laterally extending intake nipple I1 and at the other end with an outlet nipple I9 adapted to be connected by suitable pipin with 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 cook 23 is seated. The plug cock 23 is provided with an axial bore 25 with which a port 21 extending through one wall of the cook 23 communicates. The port 21 affords communication between the inlet nipple l1 and the bore 25, in order that the fuel may flow into the body of the casing l5 when the cock is in the open position shown in Fig. 7.

The cock 23 is provided with a reduced stem 29 having a dial 3| mounted thereon against relative rotation and by means of which the ment of the cook 23 away from its seat is limited by a retainer plate 33 secured to the casing l5 by means of the screws 35 and overlying the shoulder formed by the junction of the reduced stem 29 with the cook 23. A spring 31 is housed within a recess 39 at the junction of the stem 29 with the shoulder 30 and, by its engagement with the overlying portion of the plate 33, serves to maintain the cook 23 resiliently inits seat 21.

Rotation of the cock 23 in its seat is permitted in a clockwise direction without limitation, but

means are provided to limit counter-clockwise rotation thereof in certain positions. As shown in Figs. '7 and 4, the dial M is made hollow I and is provided on its inner edge with diametrically opposite rachet teeth sections 48 which cooperate with a pawl 42 mounted on the upper portion of the casing I above the retainer plate 33. The pawl '42 is secured to the casing I5 by means of a screw 44 and is maintained in yieldable engagement with the rachet teeth 48 by means of a spring 46 of usual form. As will appear hereinafter, the rachet teeth sections '48 are arranged in particular relationship with certain passages formed in the seating surface of the plug cook 23, it being understood that the cock forms the main fuel valve for controlling fuel flow for both the main and pilot burners of the appliance.

The pilot burner of this invention is adapted to receive fuel by either of two routes from the inlet I1, depending upon the position of the plug cock 23. To this end the seating surface of the plug cock 23, as shown in Figs 8 and 9, is pro-- shorter arcuate groove 55 which may also communicate with the groove 58 in the plug member 23 when in certain positions. As shown in Fig. 6. the passage 52 communicates with a passage 51 formed in an end casing 58, while the passage 54 communicates with a passage 88 also formed in the end casing 58. It. should be notedv that

passages

52 and 54 in the main casing and passages 51 and 58 in the end casing are respectively in the same plane but on diametrically opposite sides of the casings.

The end casing 58 is'secured to the main casing I5 by means ofthe screws 52 and a gas -tight joint between these .casings isprovided by a gasket 84. The passage 58 communicates with a chamber 88 in the end casing 58 and within which a pilot control valve 58 is housed. The pilot control valve 68 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 18 against the pressure of a coil spring I2 retained in the chamber 88 by means of the cap 14. The stem of the pilot control valve is suitably grooved to permit the passage of fuel therearound and is guided in an opening 18 formed in the end casing.

The passage 51 communicates with the opening 18 and it is thus apparent that when the'pilot control valve is open the fuel from the passage 68 may flow past the valve seat and into the passage 51. A sealing chamber 88. formed in the end casing'adj acent the opening 18 receives a projection 82 on the end of the valve stem 18. The sealing chamber 88 opens into the main casing l5 and leakage of 1'uel between the two ca'sings is prevented by means of adiaphragm 84 which extends across the sealing chamber "and is secured in position by means of the threaded collar 85 engaging the end casing 58.

Intermediate the ends of the passage 52 in the main casing I5 is a transversely extending passage 38. This transverse passage 88, as shown in Fig. 10, communicates with one end of a threaded passageway 98 within which an adjustable plug 92 is adapted to rotate. A T-shaped passage 94 is formed in the plug 92, one leg of which communicates with the passage 88 and the other leg of which communicates with a passage 96 formed in the end casing I5. Rotation of the threaded plug will serve to move the passage 94 into and out of registry with the passage to increase or diminish the effective area of the passage 84 and adjust the amount of fuel that flows through the passage 86. The latter passage communicates through a suitable coupling connection 98 with a conduit I88 connected, as shown in Fig 7, with a pilot burner I82.

By referring to Figs. 11 to 18 inclusive, the flow of fuel in various positions of the shut-off cock 23 may be ascertained. In Figs. 11 and 15, the cock is shown in closed position and there is no communication between the inlet nipple I1 and the port 21, or between the arcuate grooves 48 and 58 and the

passages

52 and 54, respectively. Upon being rotated from the closed position the cock first reaches the position designated light pilot on the dial 3|. Such rotation of the cock is in a clockwise direction and, as will be clear from Fig. 4, the pawl 42 is out of engagement with either of the rachet teeth sections 48 so that the dial can be rotated in a counter-clockwise direction toward the ofi position. The light pilot position of the cock is shown in Figs. 12 and 16, from which it will be apparent that the groove 48 is now in communication with both the inlet nipple II and the passage 52.

The next position of the plug cock 23, upon further rotation, is the pilot position, suitably marked upon the dial 3I and shown in Figs. 13 and 1'1, where the groove 58 afiords communication between inlet I1 and passage 54. Further rotation of the dial 3| will move the plug cock 23 to the on position shown in Figs 14 and 18. In this position the port 21 registers with the inlet nipple I1 and permits fuel to flow through the axial bore 25. Furthermore, communication between the inlet nipple and the pilot passage 54 is afforded by the arcuate groove 58 which extends across both the passage 54 and the groove 55 in the valve seat. I

It will be apparent from Fig. 4 that counterclockwise rotation of the dial from the pilot to the "light pilot position is prevented by the engagement of the pawl 42 with the rachet teeth section 48 provided on the dial between these positions. It will also be apparent that when the dial is rotated from the "on to the off" position, counter-clockwise rotation back to on" position is also prevented by the pawl and the rachet teeth section 48 between these positions.

As shown in Fig. 3, thepilot control valve aschamber I82 (Fig. 7) within which a thermoelectric assembly is adapted to be housed. This assembly includes a horseshoe electromagnet I84 seated on its base I88 in an end cap I88 which is formed integral with the end casing 58.

In order to secure the magnet I84 yieldably in position and prevent distortion thereof, a coil spring H8 is held in position on the magnet base I88 by means of a magnet retainer II2 secured by means of the screws II4 to the end cap III. A stem II5 extends between the legs'of the magnet I04 and through the magnet retainer II2, there being a clearance provided between the end of the stem H6 and the magnet base I08. The stem has slidable engagement with an armature bar II8, abutting a flange I on the stem and the bar is adapted to bridge the pole faces of the magnet I04 in the usual'manner. An armature stem spring I22 extends between the nut I20 and the magnet retainer H2 and serves to urge the armature bar II8 away from thepoles of the magnet I04.

The arms of the horseshoe electromagnet carry the coils of a wire I24, one end of which is connected by soldering or other suitable means to the head I26 of a terminal screw I28. The other end of the wire I24 is grounded as by connection to the magnet retainer II2 which is secured to the end cap I08. The terminal screw I28 is insulated from the end cap by means of the bushing I30 and is provided with nuts I32 between whichone element of a thermocouple I34 is secured. The other element of the thermocouple I34 is grounded on the end casing by being connected thereto by means of the screw I36.

The thermocouple I34 may be supported by a bracket I38 in position to be heated by the pilot burner I02, thereby to establish an electric current to the coils I24 of sufficient strength to energize the magnet I04 and hold the armature bar I I8 incontact with the pole faces thereof against the force of the spring I22, provided that the armature bar has been-moved into contact with the magnet in a manner which will hereinafter be explained.

Thermostatic control of the mainburner and safety control of the flow of fuel thereto should the pilot burner become extingulshed,. are provided in this invention by means of'a single valve. In carrying out this feature of the invention the body of the main casing I5 is made of hollow form below the portion carrying the plug cook 23 and is provided with a web I40 within which an annular valve seat member I42 is removably mounted. The valve seat member I42 carries a hollow boss I44, connected thereto by a perforated flange I45, and in relation to which a valve stem I46 is-adapted toreciprocate. A valve member I48 is secured on the valve stem I46 and cooperates with the valve seat I42 to control the flow of fuel through the ports I50 in the valve seat to the outlet nipple I8 with which the ports are aligned. It will be observed that the valve assembly is axially aligned with the thermoelectric assembly with which it is operatively associ ated.

The valve stem I46 is slidably mounted in a sleeve I52 which, in turn, is slidably'mounted in the hollow boss I44. The sleeve I52 is internally threaded for a portion of its length and carries a threaded plug I54 suitably recessed for the reception of a spring I56 which is operative between the plug I54 and the valve swm I4 The end of the plug I54 projects beyond the sleeve I52 and is adapted to engage and be operated by a clicker mechanism comprised of a pair of opposed fulcrum levers I58, fulcrum button I60 and clicker disc I62, all of which are housed within a recess I64 formed in the annular valve seat I42. The valve member I48 ,is provided with a boss I63 for the support of a spring I65 which extends to the abutment member 293 and has its opposite end supported thereon.

Thermostatic means for operating the valve I48 through the clicker disc mechanism is provided and consists of an element of the rod-and-- tube type. A tube I68 of material having a high coefficient of expansion is securely mounted at its inner end on the casing I5. The rod I68 of the thermo-responsive unit, which is of material having a low coefllcient of expansion, extends within the tube I66 and is threadedly connected at its outer end with a plug I10 anchored in the outer end of the, tube I66. The inner end of the rod I68 is recessed for the reception of a ball I12 secured in position by means of a cap I14. The cap I14 engages a sealing disc I16 secured in a recess I18 in the casing I5 by the valve seat I42 and having its inner portion urgedinto engagement with a thrust member I by the cap member I14.

As is well known, the differential in the expansion of the rod and tube underthe influence of the heat of the water in the appliance in which the device is mounted causes the rod to actuate the thrust member I80 to operate the clicker disc I62 which, in turn, operates the fulcrum button I60 and the opposed fulcrum levers I58. The levers I58 strike the plug I54 which, through the sleeve I52, actuates the valve member I48 to open position. It will be noted that the spring I58 is not compressed at this time as will be apparent hereinafter. for mounting the control in the water heater or other appliance are provided by the elongated boss I82 projecting from the casing around the rod-and-tube element. The temperature at which the valve I48 will be operated may be adjusted by means of a manually operated lever I84 attached to the rod I68 "by means of the set screw I86. The lever carries a pointer I88 for cooperation'with indicia I90 on the casing. Movement of the lever in a vertical direction will serve to rotate the rod I88 and screw this rod further in or out of the plug I10 to change the expansion differential.

Movement of the valve I48 toward and away from its seat by the thermostatic device is governed by the condition of the thermoelectric mechanism previously described. Such goveming action is effected by the-provision of a valve operating mechanism for the thermoelectric assembly which will now be described. The armature stem H6 is provided, beyond the armature bar II8, with an extension carrying the abutment member 200. The abutment member is provided with an annular recess 202 intermediate its ends and is spaced from the valve member I48 when the armature bar 8 is in the attracted or active position shown in Fig. 7.

That portion of the armature stem extension which carries the autment 200 is reduced in size and carries a retainer cap 204 within which an overload spring 206 is housed. The overload spring 208 acts between the retainer 204 and the armature bar H8 and serves to maintain uniform contact pressure between the armature and the electromagnet, as will hereinafter be described. Also carried on the reduced portion of the armature stem extension is a flexible sealing disc 208 which, together with a guide disc 2I0, is securely retained in position across the end of the chamber I02 by means of the threaded collar 2I2. As will be apparent, the function of the sealing disc 208 is to prevent the entrance of fuel into the magnet chamber I82 while at the same time permitting free movement of the armature bar II8 toward and away from attractedv position with the pole of the magnet I04.

The means for actuating the armature II8 between active and inactive positions is entirely Suitable means end casing 58. The opposite or free end of the lever is curved and extends into engagement with the diaphragm 84 on the opposite side thereof to the pilot valve extension 82. In order to support the free end of the lever 2 against lateral movement and to provide a guide therefor, there is provided an angle plate 224, secured by meansof the screws 226 to the end casing and having a slot 228 therein for the reception of the lever 2. The lever 2! is further provided with a projection 229 on the left-hand half thereof, as viewed in Fig. 5. The face of the extension 229 provides an abutment for an operating member in the form of a pin 230 which projects into the hollow casing I5 from. the end of the plug cock 23.

As will be apparent, the positions of the dial are off, light pilot, pilot and on. Fig. I of the drawings shows the control with the parts in the relationship they assume when the plug cock is in the on position and the thermoelectric control is in the active position, but when the thermostatic or control valve I48 is closed. The position of the plug cock 23 in the various positions of the dial and the relationsbip'of the operating member Him the lever 2 in such before the fuel supply is cut off from one passage and supplied to the other. Hence, the pilot flame is not extinguished during the movement of the plug cook 23 from the "light pilot" to the pilot position. 1

During this movement of the plug cock the operating member 230 is moved in a circular path against the face 229 of the lever 2M and serves to move it in a counter-clockwise direction about its pivot. Thus, when the pilot position is reached, the pilot valve 68 has been opened by this action of the lever 2M and the fuel may fiow by way of

passages

54, 60, 51 and 88 to the pilot burner I02, as shown in Fig. 6. Due to the counter-clockwise rotation of the lever 2, the center portion thereof carrying the rounded projection 2! will serve to move the armature stem I I6, together with the armature bar II8, to the left as viewed in Fig. 7. When the movement of the plug cock 23 to the pilot position is completed, the armature bar H8 is, thus seated against the pole faces of the electromagnet I04.

As shown in Fig. 21, the operating member 230 does not reach its extreme limit of movement against the face 229 of the lever 2 when the pilot valve is fully open. That is, after the pflot valve is fully opened and the armature bar is seated against the pole faces of the electromagnet, the operating member 2311 continues to move in a circular path against the face 229 although no further movement of the lever in a counter-clockwise direction is required to perform'these functions. Such movement of the positions are shown in Figs. 11 to 22 inclusive,

12, 16 and 20, the fuel may flow from the inlet T nipple I! by way of the arcuate groove 48 to the passage 52 and thence by way of passage 99 to the pilot adjusting screw 92. justing screw being in open adjusted position, the

fuel can flow through the passages 94 and 99 to the conduit Ill and thence to the pilot burner I02. It will be observed that in reaching the light pilot position the operating member 239 has moved into abutting relation with the face of extension 229 .of the lever2ll. but has not rotated sufliciently to cause actuation of the lever.

It will further be apparent that the fuel which flows to the pilot-bumer I92 in this position is not under control of any safety device.

-When the light pilo position is reached, the pilot burner I92 is lighted and after a waiting period ofaboutone minute the dial is rotated in a clockwise direction to the pilot" position. As shown in Figs. 13 and 17, the supply of fuel is, in this position, cut off from the passage 52 but flow is provided between the inlet nipple I1 and the passage 54 by means of the arcuate groove 59. However, during the changeover The pilot adthere is an overlapping of grooving and passages overload spring 206 being free of compression resumes its original length.

During the waiting period mentioned after lighting of the pflot burner, the flame from the burner, which impinges on the end of the thermocouple, serves to heat it. .The thermocouple soon generates sumcient current to energize the magnet and, when the armature bar is moved into engagement with the pole faces thereof as described, the magnet will serveto retain the armature bar in attracted position. Consequentw. although the operating member 23! moves beyond the face 229 of the lever 2 in the "pilot position, the engagement of the lever with the armature stem abutment 299 will cause the lever to be retained in the position to which it was previously moved.

The main burner is lighted by moving the dial to the on position. as shown in Figs. 14, 18 and 22. Fuel is now permitted to flow through the inlet nipple II to the port 21 of the plug cock into the main body of the casing I5. In this position, itwill be observed that the arcuate groove 5. permits gas to flow to the pilot burner also, by connectinggroov 56 with the passage 64. The indicator lever I may then be set to the desired tempe ature indicated on the casing and the control will be placed in complete operation.

tion directly to the on position, due to the ratchet teeth section provided between these points. It is necessary, therefore, that the control be operated in the various stages of light pilot to on, as any other mode of operation is prevented.

As previously described the rod I68 of the thermostatic means will actuate the valve I48 with a snap action through the clicker mechanism provided. The movement of the plug I54 and sleeve I52 which effects opening of the valve moves the spring I56 bodily without comactive to inactive position for causing movement of said thermostatic valve from open to closed position regardless of the condition of said therpressing it due to this spring being strong enough to overcome the spring I65 and the force resulting from the gas pressure on the top of the valve. The spring I56 is 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 current, causing deenergization of the electromagnet and movement of the armature bar II8 away from the pole faces. Such movement of the armature bar is caused by the armature stem spring I22 which urges the abutment toward the valve member I48. If the thermostatic mechanism is operating at this time to hold the valve I48 in open position, movement of the abutment 200 will serve to close it. Such action is due to thespring I22 of the armature stem being stronger than the spring I56 in the valve stem, thus overcoming it to move the valve I48 to closed position with a snap action.

During this movement of the abutment 280 toward the right, as viewedin Fig. 7, the lever 2I4 is rotated on its pivot in a counter-clockwise direction, permitting the pilot valve 68 to be closed by the pilot valve spring I2. Thus,

when the pilot burner is extinguished for any reason, the safety mechanism operates to close both the main control valve I48 andthe pilot control valve 68, giving a complete shut-off.

Due to the provision of the light pilot position, the operating member 230 can be positioned beyond the face 229 of the lever in the pilot" position and the lever is thus free to move in a clockwise direction should the pilot burner be extinguished. It will be apparent that if no light pilot position were provided, then the operating member 230 would necessarily have to hold the lever 2I4 in its extreme counter-clockwise position in the pilot position, as the electromagnet would not then be energized. In such event, the engagement between the operating pin 230 and the lever ,face 229 would prevent the lever from moving in a clockwise direction to close. the pilot valve, should the pilot burner become extinguished.

We claim: 1.

1. In a safety control for gaseous fuel burners, the combination of rotatable means for controlling the supply of fuel to the burner, a thermostatic valve for regulating the supply of fuel to said burner, thermostat means for adjusting said valve between open and closed positions to maintain selected temperatures, means movable from mostat, and means operable upon rotation of said controlling means for actuating said valve closing means to active position to permit thermostatic control of the thermostatic valve.

2. In a safety control for gaseous fuel burners having main and pilot burners, the combination of a main fuel valve controlling the supply of fuel to both the main and pilot burners, a main control valve intercepting the supply of fuel from the main fuel valve to the main burner, means for moving the main control valve between open and closed positions, means responsive to the presence of a flame at the pilot burner for permitting operation of the main control valve to open position by the first 'said means and being adapted to move said valve to closed position independent of said first means upon extinguishment of said flame, and means operable by said main fuel valve for resetting said flame responsive means when the pilot burner is relighted. 3. In a safety control for gaseous fuel burners having main and pilot burners, the combination of a main fuel valve controlling the supply of fuel to both the main and pilot burners, a main control valve intercepting the supply of fuel from the main fuel valve to the. main burner, means for moving the main control valve between open main control valve and release said pilot control valve to closed position independent of said first means upon extinguishment of said flame, and means operable by said main fuel valve for resetting said flame responsive means when the pilot burner is relighted.

4. In a safety control for gaseous fuel burners having main and 'pilot burners, the combination of a main fuel valve movable to different positions for controlling the supply of fuel to either the main or pilot burners, a main control valve interceptingthe supply of fuel from the main fuel valve to the main burner, a, pilot control valve intercepting the supply of fuel from the main fuel valve to the pilot burner, means for moving said main control valve to open position,

- means for moving said main control valve to closed position independent of said opening means said closing means being adapted to remain in an active-position as" long as the pilot burner is lighted, and means operable upon movement of said main fuel valve to one of said positions for moving said valve closing means to said active position.

5. In a safety control for gaseops fuel burners having main and pilot burners, the combination of a main fuel valve movable to different positions for controlling the supply of fuel to either the main or pilot burners, a main control valve intercepting the supply of fuel from the main fuel valve to the main burner, a pliot control valve intercepting the supply of fuel from the valve to closed position regardless of the condition of the thermostatic means, said means being adapted to remain in an active position as long as the pilot burner is lighted, and means carried by said main fuel valve and operable in one of said positions thereof for moving said valve closing means to said active posiiton to permit adjustment of the main control valve by the thermostatlc means.

6. In a safety control for gaseous fuel burners having main and pilot burners, the combination of a main fuel valve movable to different positions for controlling the supply of fuel to either the main or pilot burners, a main control valve intercepting the supply of fuel from the main fuel valve to the main burner, a pilot control valve intercepting the supply of fuel from. the main fuel valve to the pliot burner, thermostatic means for adjusting said main control valve to difierent positions to maintain selected temperatures, a pivoted member in operative relation with said main control valve and extending adjacent said main fuel valve, means engaging with said pivoted member for moving said main control valve to closed position regardless of the condition of the thermostatic means, said means being adapted to remain in an active position as long as the pilot burner is lighted, and means carried by said main fuel valve and engageable with said pivoted member in one of said positions of the main fuel valve for moving said valve closing means to said active position.

7. In a safety control for gaseous fuel burners having main and pilot burners, the combination of a main fuel valve controlling the supply of fuel to both the main and pilot burners, a. main control valve intercepting the supply of fuel to the main burner, a pilot control valve intercepting the supply of fuel to the pilot burner, thermostatic means for adjusting said main control valve to different positions to maintain selected temperatures, a safety control movable from active to inactive positions for causing movement of said main control valve to closed position regardless of the condition of said thermostatic means, and means for simultaneously actuating said safety control to active posi-' tion to permit adjustment of the main control valve by the thermostatic means and opening said pilot control valve.

8. In a safety control for gaseous fuel burners having main and pilot burners, the combination of a main fuel valve having a lighting and a running pilot position, a main control valve intercepting the supply of fuel from the main fuel valve to the main burner, means for operating said main control value, a pilot control valve intercepting the supply of fuel from the main fuel valve to the pilot burner, said pilot control value being closed in the lighting pilot position of the main fuel valve, means responsive to the presence of a flame at the pilot burner for permitting operation of the main control valve to open position and being adapted to move said valve to closed position together with the pilot control valve upon extingulshment of said flame, and means operable between the lighting and the running pilot position of said main fuel valve for resetting said flame responsive means when the pilot burner is relighted, said means being rendered inoperative in said running pilot position so as to permit said flame responsive means to operate.

9. In a safety control for gaseous fuel burners having main and pilot burners, the combination of a main fuel valve having a lighting and a running pilot position, a thermally operated valve intercepting the supply of fuel from the main fuelvalve to the main burner, a pilot burner control valve intercepting the supply of fuel from the main fuel valve to the pilot burner, thermoelectric means energizable by said 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 when said armature is free, a pivoted member in operative relation with said retaining means and engaging said pilot control valve, means carried by said main fuel valve and engageable with said pivoted member between said lighting and said running pilot position for moving said armature to attracted position and opening said pilot valve, said means being out of engagement with said pivoted member when the main fuel valve is in running pilot position so as to permit said arma ture to move to free position.

10. In a safety control for fuel burners, the combination of means for controlling the supply of fuel to the burner, means movable between positions for regulating the fuel supply from said controlling means to the burner, a safety control for preventing normal operation of said regulating means in one condition of the burner, said control comprising a thermocouple responsive to the heat of the burner, an electromagnet connected to the thermocouple, an armature for the electromagnet movable to an attracted position, and means operable by the controlling means for actuating the armature to attracted position without changing the position of said regulating means.

11. In a safety control for fuel burners, the combination of means for controlling the supply of fuel to the burner, means movable between positions for regulating the fuel supply from said controlling means to the burner to maintain a desired condition, a safety control for preventing normal operation of the regulating means in the absence of heat at theburner, said control comprising a thermocouple responsive to the heat of the burner, an electromagnet connected to the thermocouple, an armature for the electromagnet movable to an attracted position, a yieldable connection between the armature and regulating means, and means associated with the controlling means and operable on they connection for actuating the armature to attracted position without changing the position of the regulating means.

12. In a safety control for fuel burners, a main shut-off cock movable between open and closed positions, a combined thermostatic and safety valve interposed in the line between the shut-oflf cock and the burner, a thermostat for adjusting the valve to maintain selected temperatures, electromagnetic means responsive to the condition of the burner and operable upon the valve upon the occurrence of one condition at the burner, and connecting means between the shutoff cock and electromagnetic means for rendering the latter operable when the cock is moved to one of its positions.

' WILBUR F. JACKSON. THOMAS H. JEFFERS.