Illinois Tool Works Inc.
Mass flow meters/controllers and methods having improved accuracy

Abstract:

A disclosed mass flow meter/controller includes: a flow tube to direct a fluid from an inlet of the flow tube to an outlet of the flow tube; an actuator to cause a vibration in the flow tube; a light source to emit light; at least one beam splitter to split the light emitted by the light source into a first light beam and a second light beam; a first optical sensor to output first measurements of a first position of a first location on the flow tube based on detecting the first light beam; a second optical sensor to output second measurements of a second position of a second location on the flow tube based on detecting the second light beam; and control circuitry to determine a mass flow rate and/or a density of the fluid in the flow tube based on the first and second measurements.