Phase-sensitive detector-type electromagnetic flowmeter

An improved 60 cycles/sec sine wave electromagnetic flowmeter has been developed. By special construction of the pickup cannula and phase-sensitive demodulation, the conventional “balancing” procedure has been eliminated. Thus the operational technique is simple, and the flowmeter does not need readjustment between use. Both forward and backward flows can be measured with less than 3% error. The frequency response as determined by the use of a suppressed carrier modulated signal was 0–30 cycles/ sec without loss.

blood flow; 60 cycles/sec sine wave; suppressed carrier test

Submitted on October 26, 1964