Mass flow meter operating by the Coriolis principle

摘要

A mass flow meter operating by the Coriolis principle comprises a mechanical oscillating system having two straight measuring tubes which are clamped at both ends. The mechanical oscillating system is arranged axially in a support tube. In the center of the measuring tubes an oscillation exciter is disposed which sets the two measuring tubes into oppositely phased flexural oscillations. Oscillation sensors sensing the mechanical oscillations at equal distances on both sides of the oscillation exciter generate electrical oscillation sensor signals which are characteristic of the frequency and phase position of the sensed oscillations. An evaluation circuit receives the oscillation sensor signals and generates from their phase difference a measuring signal indicating the measured value of the mass flow. A first temperature sensor is arranged such that it measures the temperature of the support tube and generates a first temperature sensor signal indicating said temperature. A second temperature sensor is so arranged that it measures the temperature of the mechanical oscillating system and generates a second temperature sensor signal indicating said temperature. A correction circuit receives the two temperature sensor signals and imparts to the measuring signal on the basis of the temperatures measured a correction for eliminating the temperature influence on the measurement result.