| 摘要 |
PURPOSE: To automatically make fuel delivery amount compatible to alcohol concentration and kinds without requiring maintenance by a worker by feeding power to a pump by making a function that a first signal as a function of fuel pressure and a second electric signal as a function of density of alcohol fuel are combined. CONSTITUTION: A pressure sensor 102 transmitting an electric signal changing as a function of exit pressure of a fuel pump 12 is connected with an input of a pulse width modulating amplifier 106 of a circuit plate assembly 96 and a sensor 108 which is positioned at a tank transmits an electronic output signal changing as a function of alcohol density of fuel to a second input part of the amplifier 106. During an operation, the amplifier 106 transmits a pulse type dc signal to the pump 12. In this case, a duty cycle decreases as a continuous function increasing pressure of the sensor 102 and increases as a directly continuous function increasing alcohol density of the sensor 108. Therefore, when fuel alcohol concentration is prescribed one, a pump motor is driven as an inverse function of exit pressure of the pump 12 so as to keep fuel pressure constant. |
