Coriolis type apparatus for measuring mass flow of a fluid stream

PCT No. PCT/HU93/00026 Sec. 371 Date Feb. 6, 1995 Sec. 102(e) Date Feb. 6, 1995 PCT Filed Apr. 26, 1993 PCT Pub. No. WO93/22629 PCT Pub. Date Nov. 4, 1993A 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.