Abstract: Apparatus for measuring mass flow of a fluid stream comprising inlet and outlet conduits for the fluid stream, at least one resilient flow tube having fixed mounting ends communicating with the inlet and outlet conduits, a vibrator for oscillating the flow tube transverse to the axis of the flow tube, sensors for generating signals corresponding to the oscillating motion of the flow tube and a signal processing unit for determining the mass flow from said signals on the basis of the Coriolis reaction force by the fluid against the flow tube. According to the invention the flow tube is formed as a symmetrical loop around the amount ends, said loop providing a change in the direction of flow which is greater than 360.degree., and vibrator is located on the flow tube at a point adjacent the mounting ends.Method for measuring mass flow of a fluid stream, wherein the said at least one flow tube is oscillated at a resonant frequency higher than the fundamental resonant frequency of the flow tube.

Abstract: A Coriolis type apparatus for measuring mass flow of a fluid stream, comprising at least one flow conduit which is oscillated at a resonant frequency transverse to the direction of flow while said fluid flows therethrough, two sensors for generating analog signals corresponding to the motion of the flow conduit, and signal processing means for determining time difference between said analog signal, said signal processing means including means for converting said analog signals into series of digital signals and means to compute from said series of digital signals said time difference by using Fourier transformation. Each of the analog signals generated by the sensors is converted into a series of digital signals by an incremental type analog-digital converter having a comparator, an up-down counter and a digital-analog converter.