| 摘要 |
PURPOSE:To attempt to improve the combustion range in a low-temperature zone and the oxygen deficiency characteristic in a high-temperature zone by constituting an oxygen deficiency detection level temperature correction circuit by concurrently using a room temperature detecting thermistor as one for the temperature correction of the oxygen deficiency detection level. CONSTITUTION:In a case where the room temperature is high, the resistance value of a room temperature detection thermistor 17 is small. Hence, a non-inversional input potential of an amplifier 24 becomes high, and the output thereof becomes a high voltage, and the degree of contributing to lowering an oxygen deficiency detection level VB is small. When the room temperature is lowered, the resistance value of the room temperature detection thermistor 17 becomes large, the non-inversional input voltage of the amplifier 24 is lowered, and the output potential is also lowered. When the output potential of the amplifier 24 is lowered, the oxygen deficiency detection level VB is lowered to the substantially same potential. When the room temperature is lowered, combustion air is also lowered, and hence an air surplus phenomenon occurs. This causes the flame level to lower. However, since the oxygen detection level is also lowered, a constant difference is maintained in a substantially the same manner as the case where the room temperature is high, between the oxygen detection level and the flame level. |
