CORIOLIS MASS FLOW CONTROLLER

摘要

A Coriolis mass flow sensor includes a flow sensor tube, a drive device situated relative to the flow sensor tube so as to cause the flow sensor tub e to vibrate, and pick off sensors situated relative to the flow sensor tube s o as to measure the twist in the flow sensor tube due to Coriolis force. A capacitive pick off sensor is disclosed that includes at least one conductiv e plate connectable to a first voltage potential and adapted to be situated adjacent the flow sensor tube which is connected to a second voltage potential. The conductive plate is positioned relative to the flow sensor tu be so as to define a gap therebetween. The capacitance between the conductive plate and the flow sensor tube varies due to the relative motion of the conductive plate and the flow sensor tube when the flow sensor tube is vibrated. Electromagnetic, electrostatic, acoustic, and/or piezoelectric drives may be used to vibrate the flow sensor tube. The Coriolis mass flow controller may further include an integrated flow control device adapted to receive fluid from the flow sensor tube and provide flow control.