Patent ID: 6370963
Filing Date: 2002-04-16
Classification: G01F

Abstract:
An apparatus for measuring the flow rate of a flowing fluid comprising:a transmitter for transmitting bursts of electrical signals each having a first duration; a first transducer responsive to said bursts of electrical signals and located in acoustic contact with said flowing fluid, for transmitting a first acoustic energy signal along an axis parallel to a direction of flow of said flowing fluid, and for receiving at least a component of a second acoustic energy signal responsive to said flow rate of said flowing fluid; a second transducer responsive to said bursts of electrical signals and located at a distance from said first transducer and in acoustic contact with said flowing fluid, for transmitting said second acoustic energy signal and for receiving at least a component of said first acoustic energy signal responsive to said flow rate of said flowing fluid; a transit time of said received acoustic energy signals having a second duration, and said second duration being greater than said first duration of said bursts of electrical signals; a detector responsive to said received components of said first and second acoustic energy signals, as well as to said transmitted bursts of said electrical signals, for determining: a phase difference in said bursts of said electrical signals caused only by a transit time delay of said bursts of said electrical signals as said bursts of said electrical signals travel through components of said apparatus, and a phase difference between said received acoustic energy signals representing said transit time delays caused by said components in addition to transit time delays caused by said flowing fluid; and generating output signals in accordance with said phase difference signals; and a flow rate system responsive to said output signals from said detector for generating a flow rate output signal representative of only said flow rate of said flowing fluid.