| 摘要 |
PURPOSE: To obtain a fuel properties decision unit in which the fuel temperature is measured during a time lag of an ultrasonic sensor, after transmission of an ultrasonic signal into a fuel before reception thereof, the fuel density is then calculated based on the time lag and the fuel temperature and the properties of fuel are decided based on the density. CONSTITUTION: A measuring section 15 is constructed such that a temperature sensor 22 comprising a thermocouple is provided on the bottom 16B of a bottomed tubular body 16 and an ultrasonic sensor 20 is provided at the cover part 19. An ultrasonic signal transmitted from the ultrasonic sensor 20 is reflected on the temperature sensor 22 and an accurate density is calculated based on the time lag and the fuel temperature. Fuel properties, e.g. light fuel and heavy fuel, are then decided based on the density and an engine is controlled according to the properties. |
