PURPOSE: To permit maintaining of stabilized combustion condition by a method wherein NOx gas in exhaust gas is reduced and lift back is prevented, even upon combustion with the maximum or the minimum amount of combustion.
CONSTITUTION: A nozzle damper 31 is reciprocated into a direction, orthogonal to the axial directions of respective thin fuel combustion burners 13 and thick fuel combustion burners 15, based on the result of checking of the value of control current for controlling the opening degree of gas proportional valve. As a result, the opening areas of mixture introducing ports 17, 21 are narrowed or widened. When the opening areas of the mixture introducing ports 17, 21 are narrowed, the supply of mixture of a primary air rate coped with a reducing amount of combustion to the burner 1 is permitted. On the contrary, when the opening areas of the mixture introducing ports 17, 21 are widened, the supply of premixture of a primary air rate, coped with the amount of increasing combustion, to the burner 1 is permitted.
SHIGESUMI TSUKASA
NAKANO KUNIHIKO
SHICCHI YOSHINORI
ADACHI KEIJI
NIPPON UPRO KK