Automatic calibration of ultrasonic distance measurement instruments - using rapid rise time reference pulse from discharging piezoelectric element

摘要

The automatic calibration device is for ultrasonic distance measurement equipment and is economically protected against ambient influences and operates without the effects of first order transducer delays tending to degrade the measurement of rapidly varying distances. The device has a rapid response time and the time of emission of its reference measurement pulse is optional over a wide range. An auxiliary acoustic transducer (2) is placed at a defined reference distance (22) from the main transmitting-receiving acoustic transducer.