(under subclass 170.11) Subject matter wherein the determination of the velocity or the direction of fluid flow is made by measuring or sensing the effect of the fluid flow on a traveling compressional wave having a frequency within either the sonic or ultrasonic frequency range.
SEE OR SEARCH THIS CLASS, SUBCLASS:
645+, for measuring acoustic parameters, per se.
861.18+, for determining rate of flow, per se, by measuring vibration or acoustic energy.
