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US 4,243,373 AGranted
Direct ignition gas burner control system
AssigneeEmerson Electric Co.
InventorsCarl F. Fernstrom, Charles D. Visos
Life of this patent
Estimating the term…
Abstract
A gas burner control system wherein a burner is directly ignited by an electrical resistance igniter includes a pressure actuated switch effective to permit automatic re-cycle of the system in the event of an electrical power interruption or a gas pressure failure, and to prevent such automatic re-cycle in the event of an ignition failure.
Claims12
In a gas burner control system,
- a burner;
- an electrical resistance igniter for igniting said burner;
- a gas valve device including first and second valves connected fluidically in series;
- a thermostatically actuated switch means including a switch having a cold contact position and a hot contact position, and including a temperature sensing portion;
- said temperature sensing portion being positioned with respect to said igniter so as to cause said switch to be in said cold position when said igniter is below a predetermined temperature sufficient to ignite gas and in said hot position when said igniter is above said predetermined temperature, and being positioned with respect to said burner so as to be impinged by a burner flame for maintaining said switch in said hot position;
- first circuit means including said switch in said cold position for effecting energizing of said igniter;
- second circuit means including said switch in said cold position for effecting opening of said first valve;
- a pressure actuated switch electrically connected in parallel with said thermostatically actuated switch in said cold position and in series with said thermostatically actuated switch in said hot position;
- said pressure actuated switch being actuated to a closed contact position in response to gas pressure when said first valve is open for providing a hold-in circuit for maintaining said first valve open;
- and
- third circuit means including relay means, said thermostatically actuated switch in said hot position, and said pressure actuated switch in said closed contact position for effecting de-energizing of said igniter and for effecting opening of said second valve,
- said igniter having sufficient mass to remain above said predetermined temperature for a short time after being de-energized for effecting ignition of said burner.
9 more elements
In a gas burner control system,
- a burner;
- an electrical resistance igniter for igniting said burner;
- first and second valves connected fluidically in series for controlling gas flow to said burner;
- said first valve including a controlling electrical winding;
- said second valve being a pressure operated valve located downstream from said first valve and defining a chamber therebetween;
- a first expansible chamber operatively connected to and effective to open said second valve when sufficient gas pressure is applied thereto;
- a first branch passageway leading from said chamber between said first and second valves to said first expansible chamber;
- a third valve in said first branch passageway for controlling flow of gas to said first expansible chamber and including a controlling electrical winding;
- a pressure actuated switch having an open contact position and a closed contact position;
- a second expansible chamber located between said first and second valves and operatively connected to and effective to actuate said pressure actuated switch to its said closed contact position when exposed to a predetermined gas pressure;
- a second branch passageway leading from said first expansible chamber to a point downstream from said second valve for exhausting said first expansible chamber when said first or said third valves close whereby said second valve is closed;
- a thermostatically actuated switch having a cold position and a hot position;
- a thermostatic actuator arranged to be heated by said igniter and operative when said igniter is above gas ignition temperature for moving said thermostatically actuated switch to its said hot position, and arranged to be subsequently heated by a flame from said burner for maintaining said thermostatically actuated switch in its said hot position;
- first circuit means including said thermostatically actuated switch in its said cold position for effecting energizing of said igniter;
- second circuit means including said thermostatically actuated switch in its said cold position for effecting energizing of said winding of said first valve for opening said first valve;
- and
- third circuit means energized when said thermostatically actuated switch is moved to its said hot position for effecting de-energizing of said igniter and for effecting energizing of said winding of said third valve for opening said third valve which effects opening of said second valve,
- said pressure actuated switch being electrically connected in parallel with said thermostatically actuated switch in its said cold position for maintaining said winding of said first valve energized.
15 more elements
Dependencies are inferred from the claim text.