| 摘要 |
PURPOSE: To ensure the detecting precision of a liquid level detection using an ultrasonic sensor. CONSTITUTION: Ultrasonic sensors A, B are loaded on the sensor loading parts 21a, 21b of a sensor case 20, and mounted on the outside of a vessel 10 together with a circuit board 30. At this mounting, elastic packings 24a, 24b are fitted to the top end of the loading parts 21a, 21b, and a sealing agent 44 is applied to the bottom parts of the loading parts 21a, 21b to mount the sensor case 20. A pressure is added to the packings by the mounting, the air in the critical surface between the bottom surface of the loading parts 21a, 21b and the vessel 10 is eliminated to seal them. Each ultrasonic sensor A, B transmits an ultrasonic wave, and receives the ultrasonic wave reflected by the opposite side of the vessel 10 to detect the liquid level in the vessel 10. |
