Patent ID: 7258025

Claim:
A Coriolis flowmeter comprising: a forced vibration means for vibrating from outside a pipeline through which a fluid to be tested flows and generating a fine rotational vibration in the fluid to generate a Coriolis force in the fluid; means for suppressing a higher-order vibration by limiting a Coriolis vibration which vibrates with a vibration axis different from the vibration axis of a forced vibration and which is induced by the Coriolis force to a vibration close to a one-axis vibration with respect to the vibration direction of the Coriolis vibration through a combination of a rigid frame which is not easily deformed and an elastically deformable portion which is subject to deformation; a forced vibration control means for effecting driving at a drive frequency that makes a frequency of the forced vibration of the pipeline caused by the forced vibration means be one time or more as high as a Coriolis natural frequency that is a natural frequency in a direction of the Coriolis vibration; means for obtaining a vibration amplitude of the forced vibration generated by the forced vibration means; means for obtaining a vibration amplitude of the Coriolis vibration generated by the Coriolis force generated by the forced vibration; and a mass flow rate computing means for computing a flow rate of the fluid flowing through the pipeline from a ratio of the amplitude of the forced vibration caused in the pipeline by the forced vibration means and the amplitude of the Coriolis vibration generated by the Coriolis force and a value of the frequency of the forced vibration.