FLOW MEASURING INSTRUMENT OF FLUID

摘要

Measurement control section (4) for controlling an operation of measuring a travel time of an ultrasonic wave, which operation is done by time measuring section (11), works based on a high rate clock supplied from ceramic oscillation circuit (16) during the time measuring operation. Clock control section (18) stops the high rate clock supplied from ceramic oscillation circuit (16) every time when time measuring section (11) finishes its time measuring operation, and controls a standby time between an end of measuring the travel time and a start of carrying out the next measuring step by using a low rate clock supplied from quartz oscillation circuit (15).