| 摘要 |
PROBLEM TO BE SOLVED: To provide a liquid level detector for accurately detecting the position of a liquid level even when the position of the liquid level is low, that is, even if the position of the liquid level is substantially the same level as a container bottom part. SOLUTION: A calibration tank 4 is provided on a bottom surface 31 serving as an inner surface of a bottom part of a fuel tank 3, the tank 4 being separately stored with a fuel 5 and quipped with a reflector 41 on an upper part thereof. An ultrasonic sensor 2 is mounted on an outer surface 32 of the bottom part of the fuel tank 3 in such a manner that an ultrasonic can be emitted toward a liquid level 51 and a piezo-element 21 partly overlaps with the reflector 41 of the tank 4 in a direction vertical to the tank 3. The fuel liquid level detector 1 can be actualized capable of accurately detecting the position of the liquid level 51 even if the liquid level 51 is low positioned, that is, substantially at the same as the surface 31, by making it possible to calibrate the propagation speed of the ultrasonic in the fuel 5 with the interior of the tank 4, or specifically, the interior of a storage space 45, filled with the fuel 5 at all times, wherever the liquid level 51 is positioned in the tank 3. COPYRIGHT: (C)2004,JPO |
