Flame sequencing system for gas cooker - uses safety logic circuit to activate supply valve to control heating by ON=OFF action

摘要

The sequencer contains a switch with several positions which sets the cyclic on-off ratio of the flame. The switch provides a logic level signal for a safety circuit in which a lamp signals the state of safety for the gas supply valve. This circuit controls operation of a switch circuit which controls the flow of current in the ignition circuit and in the gas supply valve. The safety circuit receives an input from the igniter electrode to switch off the gas supply if a flame does not occur. A pushbutton resets the circuit. The safety operation is maintained even when an electrical power failure occurs and is subsequently re-established.