Safety cut=out for intermittently operating gas burner - has gas supply valve solenoid connected via contacts of thermocouple to switch off when flame is off beyond timer limit

摘要

The safety device for a gas burner is connected to a gas supply line through a manual tap and a solenoid valve actuated by a thermocouple adjacent to the burner. The burner is controlled so that it operates intermittently. The solenoid valve is coupled to the electric supply through a pair of contacts forming part of a time switch which is connected to the thermocouple. The connection is such that the pair of contacts are closed while the thermocouple is heated by the flame from the gas burner, and are opened when the flame is extinguished, after a delay interval determined by the timer switch. The timer switch is formed from a bi-metallic strip heated by an electric resistance connected to the supply through a switch controlled by the thermocouple. The system is partic. applicable to domestic cookers.