COMBUSTION CONTROL DEVICE

摘要

PURPOSE:To provide a control device having a high adjusting ratio of combustion and a superior stability in air fuel ratio by a method wherein an air volume variable mechanism is controlled in such a way as a pressure difference sensed by a pressure sensor between the air throttle and the gas throttle becomes zero. CONSTITUTION:A hot water temperature control circuit 15 amplifies a difference in signals of thermistor 12 and a temperature setting unit 14, adjusts the electric current in a solenoid coil for a gas proportional valve 13 and automatically adjusts the gas volume in such a way as the hot water temperature becomes equal to the desired temperature. A pressure difference sensing unit 16 for use in sensing the pressure difference between the upstream side of the air throttle valve 2 and the upstream side of the gas throttle valve 5 generates an air signal proportional to the pressure difference. The air fuel ratio control circuit 17 receives the signal from the pressure difference sensor 16. When the pressure difference becomes a positive value, the number of rotation of the air blower 1 is decreased by the number of rotation control circuit 19 and in turn when the pressure difference becomes a negative value, the number of rotation of the blower is increased. Thereby, it is made possible to obtain a combustion control device having a high adjusting ratio of combustion volume and a superior stable air fuel ratio without making a large blower or valve device.