PURPOSE: To obtain a superior radiation performance without requiring any heaters for preheating a catalyst and evaporating fuel by a method wherein a wick is descended by a desired height for a specified period of time when a reaching of the desired temperature in an oxidization catalyst layer is detected by means for detecting its temperature.
CONSTITUTION: When a temperature sensor 10 for an oxidization catalyst layer 6 detects a desired temperature in the layer, a control circuit 13 is energized, a motor 11 is operated to lower an extremity end of a wick 2 from its igniting position to a flame diminishing position. Thereafter, as the wick 2 is lifted again, a flame is not formed at a secondary air port 5, but only an amount of gasified fuel is recovered and premixture gas reaches to the oxidization catalyst layer 6, and then a catalyst combustion is started. Subsequently, the combustion amount is varied in response to an adjustment of the wick height through a main operation part 3 and a stable catalyst combustion is carried out at a suitable combustion amount. Therefore, it is not necessary to provide any preheating heater for the oxidization catalyst layer 6 and a heater for gasifying fuel. A required electrical capacitance is only for a power supply for the ignition heater and the motor 11, resulting in that a dry cell is sufficient for operation and thus the unit can be made a cordless equipment.
NISHINO ATSUSHI
SUZUKI JIRO
HOSAKA MASATO
