PURPOSE: To prevent an unburnt gas from occurring when the heater of an igniter is broken, by preheating a sensor for detecting the combustion state by the igniter, providing a circuit for detecting the preheating, and feeding fuel after the completion of the preheating of the sensor.
CONSTITUTION: In case when the burning operation of the device is extinguished, and when reignition thereof is desired, the temperature of the vaporization cylinder is high, and a sensor 9 is also heaed enough. However, since a little period is requied until an igniter 12 is heated to redness, it should be avoided that fuel is fed until the igniter is heated well to redness. Therefore, when the output (j) of a comparator 53 becomes the "Hi" output, and a current is passed to a coil 57 of a relay Ry3 and until an oil delivering pump 16 is operated, the capacity of a condenser 55 is set such that the period required to allow the igniter 12 to become red hot is taken into consideration. Accordingly, after the completion of preheating of the vaporization cylinder and the sensor 9 and until the igniter 12 is heated to redness, the fuel is fed to prevent an unburnt gas from occurring when reignition is performed.
MORI KEIICHI
YAMAMOTO KATSUHIKO
UCHIDA KUNIAKI
