Sicherheitsvorrichtung eines Brenners zur Zündung der Flamme, Detektion der Flamme und Steuerung der Gaszufuhr

An igniter nozzle, adjoining the main burner, is equipped with two electrodes connected to the spark generator (20). An oscillator (21) and a discharge circuit (22) produce a 15 kV beak-down lasting 5 microseconds. Operation is associated with an ionisation detector (11) using the same electrodes, which ascertains whether a flame is present. Its signal is compared with a preset value; if a flame is detected the oscillator is suppressed. The circuitry also includes boost amplifiers for opening (27) and for maintaining open (24) the gas admission valve (25); their output voltages exceed that of the power supply battery, which is insufficient to open the valve. Accidental opening is thus averted. The equipment is further described in European Patent 0 821 199 (q.v.).