US2707518A

US2707518A - Fuel control means

Info

Publication number: US2707518A
Authority: US
Publication date: 1955-05-03
Anticipated expiration: 1972-05-03

Description

May 3, 1955 w. A. RAY 1 2,707,518

FUEL CONTROL MEANS Filed Sept. 11, 1950 IN V EN TOR.

,Qr aQA/EVE United States atent FUEL CONTROL MEANS William A. Ray, North Hollywood, Calif., assignor to General Controls Co., Glendale, Califi, a corporation of California Application September 11, 1950, Serial No. 184,142

Claims. (Cl. 158-136) The present invention relates to an improved control system for gas operated devices such as clothes driers, kitchen ranges, console heaters and the like, characterized by the fact that the system is fool proof, safe and in general relates to a system of the character described and claimed in my prior United States Letters Patent 2,294,694, patented September 1, 1942, for safely controlling, from a remote position, the operation of a gas burner.

The present invention contemplates a self-contained control system for apparatus of the type mentioned above in which a three-way diaphragm operated valve and an associated pilot valve operated by thermoelectric energy is used to control the operation of a main gas burner without the necessity of an external electrical power supply.

An object of the present invention is therefore to provide a control system for this type of apparatus having the aforementioned desirable features.

A specific object of the present invention is to provide an improved control system of this type the installation of which does not necessitate the use of an external electrical power source so that the system may be used in isolated localities where no such power source is conveniently available and in those instances where it is not desired or practical to run electrical conduit from the control to the source of electrical energy.

Another object of the present invention is to provide an improved control system of this character which consists essentially of a diaphragm operated three-way valve, a pilot burner and a one-way pilot control valve energized in accordance with thermoelectric energy developed by said pilot burners, these elements being associated in a manner characterized by its simplicity to achieve the aforementioned indicated purposes.

Another object of the present invention is to provide a system of this character which incorporates a pilot burner fed with gas flowing through a chamber having a diaphragm, the diaphragm actuating a main fuel valve which controls the flow of gas to the main burner, and such chamber being supplied with gas directly from the main supply conduit through a thermoelectric controlled valve, the operation of which is controlled by the presence of the pilot burner flame so that opening and closing of a'shut-off cock controlling the flow of gas to the main burner may not lead to dangerous situations.

Another object of the present invention is to provide an improved control system of this character in which the supply of gas to the main burner is prevented until safe ignition of the associated pilot flame has resulted in actuation of a safety device.

The features of the present invention which are believed to be novel are set forth with particularity in the appended claims. This invention itself, both as to its organization and manner of operation, together with further objects and advantages thereof, may be best understood by reference to the following description taken in connection with the accompanying drawings in which:

The single figure is a view showing, partly in structural and partly in schematic form, apparatus and the system embodying features of the present invention.

The apparatus shown includes a manually operable gas cock 10, a three-way diaphragm operated valve 11, a one-way pilot valve control 12, a main gas burner 13. a pair of pilot burners 14, 15, an initiating heat source 16, a thermocouple 17 cooperatively associated with the pilot burner 15, an ignition tube 18, and interconnecting conduits and wiring. I

The initiating heat source 16 is positioned near one open end of the ignition tube 18 and may be either an electric coil, a small pilot flame or a match lighted by the housewife or other operator.

The movable parts of valve 11 and control 12 are shown in the normal positions they assume at the time the unit is being started into operation or at the time the system is closed down with the gas cock 10 shut off. In this condition it is observed that the flexible diaphragm 21 normally biases the valve element 22 attached thereto downwardly against the cylindrical valve port 23 to thereby close off communication between the chambers 24 and 25 in the valve casing 27. It is noted that the chamber 24 is in communication with the gas supply conduit 20 through the gas cock 10 and that the chamber 25 is in communication at all times with the main gas burner 13. chamber 24 is in communication, in this initial condition, with the pilot burner 14 through the cylindrical valve port 26 which is aligned axially both with the valve port 23 and valve disc 22. Thus, under these initial conditions gas flows from the supply conduit 20 to the pilot burner 14 through a path which includes the gas cook 10 in its open position, the chamber 24, valve port 26 and interconnecting gas conduit 28. The gas issuing from the burner 14 may be ignited by applying heat to the same and such heat may be supplied through the ignition tube 13 extending between the pilot burner 14 and the heat source 16.

in this initial starting period, it is noted that gas is prevented from flowing to the pilot burner 15 by the movable valve element 32 of the pilot control 12. The pilot burner 15 is in communication with the chamber 33 in the three-way valve casing 27 through conduit 34 and in communication with the chamber 35 in the control wall casing 12A through conduit 36. It is noted that the end of the conduit 36 and the movable valve element 32 comprises a pilot valve having reference numeral 30. In turn, the chamber 35 is in communication with the gas supply conduit 20 through conduit 38. Normally, in the deenergized condition of the solenoid 40 in control unit 12 the associated magnetically operated combina tion armature and valve element 41 is biased by means of coil compression spring 50 into valve closing engagement with the end of conduit 36, thus preventing the gas in chamber 35 from flowing into the chamber 33. Such gas flow from

chambers

35 and 33 to the pilot burner 15 is permitted however when the solenoid winding 42 is energized, in which case the combination armature and valve element 41 is attracted to the solenoid leg 44 and pivots about the extremity of the other solenoid leg 45 against the action of the spring thereby placing

cham bers

35 and 33 in communication.

Thus, after the gas flowing from pilot burner 14 is ignited, the thermocouple 17 in heat transfer relationship to the burner 14 is heated sufliciently'to produce sufiicient current flow through the solenoid winding 42 to cause the valve element 32 to move to valve opening positionwhereupon gas flows from the supply conduit 20 and chamber 35 into the chamber 33 and to the pilot burner 15; the gas then issuing from the pilot burner 15 is ignited by the heat from pilot burner 14. Further, the gas pres- It is noted also that the' sure in chamber 33, at this stage is sufficient to move the diaphragm 21 and associated valve 22 upwardly to a position where the valve element 22 cooperates with the valve port 26 to thereby shut off the flow of gas to the burner 14 while simultaneously allowing gas to flow from the chamber 24 through port 23 to the main burner 13. The gas then flowing from the main burner 13 is ignited either by the pilot burner 14 or pilot burner 15 which are both being supplied with gas during the time the valve 22 travels between the valve ports 23 and 26. The pilot burner 15 is in heat transfer relationship to the thermocouple 17, in the same manner as is pilot burner 14 so that the heat from pilot burner 15 alone is sufficient to energize the solenoid winding 42 in sufficient amount to maintain the valve element 32 in open position.

From the foregoing, the basis for calling the valve 11 a three-way valve is clear, for in a first extreme position of the valve element 22, shown in Figure 1, only port 26 is open, in a second or intermediate position of valve element 22, both ports 23 and 26 are open, and in the third or other extreme position of element 22, port 23 alone is open.

It is thus observed that gas flow to the main burner 13 is prevented until safe ignition of the pilot flame 15 has been accomplished, as determined by energization of the solenoid winding 42 in accordance with electrical energy developed in the thermocouple 17. While the drawings show a thermocouple 17 and solenoid winding 42 and associated valve 32, 36 for this purpose, it is noted that other similar means may be used for the same purpose. For example the thermocouple 1'7 and control 12 may be substituted by a conventional expansion rod operated pilot valve with the expansion rod in heat transfer relationship to the pilot burners 14 and 15 in the same manner as is the thermocouple I7 and with the valve thereof interposed between the conduits 36, 38.

1t is observed further, with the apparatus described, it is possible to turn the gas cock 10 on and off without a resulting accumulation of large amounts of unburned gas in the heating unit, which unburned gas might otherwise be susceptible of producing an explosion. This condition is prevented by the gas pressure in the chamber 33 resulting from energization of solenoid winding 42. Gas flows to the chamber 33 only so long as the solenoid 40 is actuated and regardless of whether or not valve 10 is open or closed. Thus, should the operator turn off the gas cock 10 and immediately turn on the same the pilot burner 15 is still in condition for igniting the resulting gas flow from the main burner 13. And, when no gas is being supplied to pilot burner 15 the valve element 22 prevents flow of gas to the main burner 13 regardless of whether the cock 3.0 is opened or closed.

While the particula embodiments of the present invention have been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made without departing from this invention in its broader aspects and, therefore, the aim in the appended claims is to cover all such changes and modifications as fall within the true spirit and scope of this invention.

I claim:

1. In a control system of the character described, a valve casing, said casing having two spaced aligned ports, a valve element movable from one extreme position wherein it is in valve closing engagement with one of said ports, said valve element being movable to a second extreme position wherein it is in valve closing engagement with the other one of said ports, a diaphragm, means associated with said diaphragm for normally biasing said valve element in valve closing engagement with said one port, a gas chamber including said diaphragm, means including said diaphragm whereby pressure in said chamber, exceeding a predetermined amount, is effective to move said valve element to said other extreme position in valve closing engagement with said other port, a main gas burner in communication with said one port, a first lit pilot burner in communication with said other port, a second pilot burner in communication with said chamber, thermal responsive means in heat transfer relationship to both said first and second pilot burners, a main supply line, and a valve controlled by said thermoelectric means controlling the flow of gas from said supply line to said chamber.

2. The arrangement set forth in claim 1 in which a shut-off cock controls the flow of gas from said supply line to each of said ports.

3. in a system of the character described, a valve casing, a pair of spaced ports, a valve element cooperating with each of said ports to close off the same alternately and to allow both of said ports to be open simultaneously, a gas chamber including a movable diaphragm, means connecting said diaphragm to said valve element to produce movement of the same between said valve ports, means associated with said diaphragm normally biasing said valve element into valve closing relationship with one of said ports, a first pilot burner in communication with said one port, a main gas burner in communication with the other one of said ports, a second pilot burner in communication with said chamber, thermal responsive means in heat transfer relationship to both said first and second pilot burners, and valve means controlled by said thermal responsive means for controlling the flow of gas to said chamber.

4. In an arrangement of the character described, a valve casing having two spaced aligned ports, a fuel inlet to said casing, a valve element cooperating alternately with said ports to prevent gas flow from said inlet through the one or the other, as the case may be, a diaphragm, a control chamber including said diaphragm, means interconnecting said diaphragm with said valve element whereby said valve element is effective to move between said two ports and to close the same, depending upon the gas pressure within said chamber, one of said ports being connectable to a pilot burner, and the other one of said ports being eonnectable to a main fuel burner and thermal responsive means sensitive to the heat developed by said pilot burner controlling the flow of fuel to said control chamber.

5. In a control system of the character described, a main burner, an auxiliary pilot burner, a main pilot burner, a manually operated shutoff valve having an inlet side and an outlet side, a gas supply line connected to said inlet side of said valve, a plurality of valve means which are diaphragm operated, one of said valve means being interposed between the outlet side of said shutoff valve and said main burner, a second of said valve means being interposed between the outlet side of said shutoff valve and said auxiliary pilot burner, thermal responsive means in heat transfer relationship to the flame produced by each of said auxiliary and main pilot burners, a control valve controlled by said thermal responsive means interposed in a communicating passageway between the inlet side of said shutoff valve and said main pilot burner, a control chamber which includes, as an element thereof, the diaphragm of said diaphragm operated valve means, and said control valve being interposed between the inlet side of said shutoff valve and said chamber.

6. The arrangement set forth in claim 5 in which an igniter tube is in communication with said auxiliary pilot burner.

7. The arrangement set forth in claim 5 in which said plurality of valve means are alternately effective to allow the flow of fuel to said auxiliary burner and to said main burner.

8. The arrangement set forth in claim 5 in which an igniter tube is in communication with said auxiliary pilot burner, and in which said plurality of valve means are alternately and jointly effective to allow the flow of fuel to said auxiliary burner and to said main burner.

9, In a control system of the character described, a main burner, a pilot burner associated therewith, thermal responsive means in heat transfer relationship to the flame produced by said pilot burner, a gas supply line, a shutofl? valve having an inlet and an outlet, said inlet being connected to said gas supply line, a diaphragm operated valve interposed between said valve outlet and said main burner, a gas pressure chamber which includes, as an element thereof, the diaphragm of said diaphragm actuated valve, a valve operated by said thermal responsive means interposed in a communicating passage between said valve inlet and said chamber, and said pilot burner being in communication with said chamber, whereby said pilot burner may remain ignited when said shutofi valve is closed, a second pilot burner associated with said thermal responsive means to heat the same, said second pilot burner being in communication with said valve outlet, and the flow of gas to said second burner being controlled by said diaphragm actuated valve.

10. In a control system of the character described, a

main burner, a pilot burner associated therewith, thermal responsive means in heat transfer relationship to the flame produced by said pilot burner, a main supply line, a diaphragm actuated valve, a shut-01f cock, said cock and said diaphragm actuated valve being serially connected in a communicating passage between said main supply line and said main gas burner, a gas chamber including, as one element thereof, the diaphragm of said diaphragm actuated valve, a valve operated by said thermal responsive means, the last mentioned valve being interposed between a point in said main supply line on the inlet inside of said cock and said chamber, and said chamber being in communication with said pilot burner, a second pilot burner associated with the first mentioned burner and in heat transfer relationship to said thermal responsive means, said second pilot burner being normally in communication with said main supply line through said shut-oil cock, said diaphragm actuated valve including a valve element automatically movable to allow the flow of gas to said second pilot burner when said diaphragm actuated valve is eifective to prevent the flow of gas to said main burner.

References Cited in the file of this patent UNITED STATES PATENTS 1,636,770 FoX July 26, 1927 1,971,882 Tuck Aug. 28, 1934 2,372,564 Engholdt Mar. 27, 1945 2,506,403 Witzel May 2, 1950