Transducer of the vibration type

Abstract

Vibration type measurement transducer has a curved vibrating measurement pipe (10) with a counter vibrating element (20) running approximately parallel to it between end coupling pieces (31, 32). An excitation arrangement (40) sets the pipe vibrating with a sensor arrangement (50) to measure vibration. Stiffness of inlet (11) and outlet (12) pipe connections is selected so that their resonance frequency is matched to the excitation frequency.

Description

technical field [0001] The present invention relates to vibrating instrument transformers particularly suitable for use in Corrosion-flow meters. Background technique [0002] For determining the flow rate of fluids flowing in pipelines, especially liquids, measuring devices are often used which generate Coriolis forces in the fluid by means of vibrating instrument transformers and connected control and evaluation electronics, and A measurement signal representing the flow is derived from this force. [0003] Such instrument transformers, in particular their use in Coriolis flowmeters, have already been known and are used industrially. For example, US-A 55 49 009 describes Corio-flowmeters with each a vibrating instrument transformer reacting to the flow rate of a fluid flowing in a pipeline, the instrument transformer comprising : [0004] - a vibrating, curved measuring tube for guiding the fluid during operation, which communicates with the pipeline via an inlet fittin...

AI Technical Summary

Problems solved by technology

A disadvantage in this case, however, is that the mass of the counter vibrator required to achieve a sufficiently strong damping of the transverse forces increases disproportionately to the nominal width of the measuring tube

This is the biggest disadvantage of this type of instrument transformer, because the use of components of this quality always means increased installation costs, both when manufacturing and when installing the measuring device in the pipeline

Also, as the mass increases, the minimum natural frequency of the instrument transformer gets lower and lower, in which case it is difficult to ensure that this minimum natural frequency is always that far away from the same lower natural frequency on the connected pipeline

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