| 摘要 |
PROBLEM TO BE SOLVED: To precisely measure the distance between a vibrator and the surface of the sea by transmitting ultrasonic pulses vertically downwards by horizontally holding the vibrator at all times by means of a horizontal holding mechanism. SOLUTION: A horizontal holding mechanism 3 constituted of, for example, a gimbal mechanism is attached to a lower attaching plate 6B of a base-side end section 6 of an ultrasonic transmitter-receiver and a vibrator 1 and a reflecting plate 7 are fixed to a supporting member at the lowest section of the holding mechanism 3. The vibrator 1 is constituted by stacking, for example, ring type vibrators 1A-1C upon one another, transmits ultrasonic pulses S1-S3, and receives returning echo pulses R1-R3 reflected by the surface of the sea. A reflecting shade 1D made of a relatively heavy material is provided at the front end of the vibrator 1, so as to prevent the occurrence of measurement errors by blocking the echo pulses R1-R4 made incident directly upon the vibrator. At the same time, the vibrator 1 is held horizontally by lowering the center of gravity of the vibrator 1. Since the reflecting plate 7 reflects the pulses S1-S3 from the vibrator 1 at a reflecting angle of 45 deg. so as to make the pulses S1-S3 to advance vertically downwards, the surface and, accordingly, the water level of the sea can be measured precisely. |
