Gas instrument

Abstract

Abstract PURPOSE:An anti-oxygen-deficiency safety device less liable to make erroneous operation, adapted to cut-off the supply of gas when the change of flame on a burner due to an oxygen deficiency lasts longer than a predetermined period of time. CONSTITUTION:A thermocouple 3 is disposed in the nozzle of an oxygen deficiency detecting burner 2 which plays also the role of a pilot burner for a main burner 1. The output from the thermocouple 3 is delivered to a resistance 29 of an amplifier circuit IV so as to become a biasing voltage. This voltage is added to an oscillation input coming from an oscillation circuit II which includes resistances 20, 21, 23, 25, PUT 22 and a capacitor 24. The resulting voltage is amplified to a transformer by an operation amplifier 30 the output from which is delivered 32. The output from the transformer 32 is rectified by a rectifier circuit V and is used for opening and closing a solenoid valve 7. A timer circuit III constituted by contact 26 adapted to be closed when the burner is put on and a capacitor 27 is interposed between the oscillation circuit II and the amplifier circuit IV. When the change of fluctuation of the flame is ceased in a predetermined period of time, the capacitor 27 makes a discharge to hold the output from the amplifier 30.

Inventors

• 👤 Akira Matsuda
• 👤 Noriyoshi Ohashi

Bibliographic Details