| 摘要 |
PURPOSE:To make it possible to determine air-fuel ratio and to make it possible to keep the air-fuel ratio constant in a wide range by a method wherein an electromagretic pump is driven with a frequency proportional to the quantity of air supplied from a blower and fuel oil is supplied to an evaporator. CONSTITUTION:When the quantity of air from a blower 2 is selected so as to adjust the amount of combustion, the rotary vane 8 provided in a combustion air passage 3 rotates with the number of revolutions proportional to the quantity of air from the blower 2. Accordingly, light is transmitted to a photoreceiver 11 from a projector 10 and a pulse signal of a frequency corresponding to N times the number of revolutions of the rotary vane 8 generates at a connecting point 17 of a signal generator 14. This pulse signal is divided by a frequency divider 18 into frequency signals in a range suitable for driving the electromagnetic pump 5 and the divided signals are used to drive the pump 5 with the frequency proportional to the quantity of air from the blower 2. Consequently, it is possible to determine the air-fuel ratio easily and to keep constant the air-fuel ratio in a wide range. |
