CONTROLLING DEVICE FOR AIR-FUEL RATIO OF BURNER

摘要

PURPOSE:To prevent the air-fuel ratio from largely deviating at the unstable initial time of ignition, by controlling the air-fuel ratio by the controlling rate corrected by an air-fuel ratio controller and is stored in a memory at the previous time, until a combustion sensor can output normal output signals after a burner is ignited. CONSTITUTION:A fuel pump 11 controls the feeding rate of fuel to a burner 14. A fan 13 supplies combustion air to the burner. A flame rod 16 detects the state of combustion in the burner 14. A controller 17 controls driving of a fuel pump 11 and a fan 13. The sequence controller 19 of a controller 17 controls the drive in accordance with a predetermined sequence. An air-fuel ratio controller 22 controls to correct the fan 13 or the fuel pump 11 in accordance with signals from the flame rod 16. They are output during combustion in the burner. A memory 23 stores the data of controlling rate which is corrected by the air-fuel ratio controller 22. An initial time controlling circuit 24 controls the air-fuel ratio by the value of a signal stored in the memory 23 until the output from a combustion sensor 16, that is the flame rod 16, is stabilized after combustion starts in the burner.