Patent ID: 6484565
Filing Date: 2002-11-26
Classification: A61B,G01N

Abstract:
An apparatus for determining the viscosity of a fluid over plural shear rates using a decreasing pressure differential, said apparatus comprising:a lumen having a first end and a second end and being positioned at an angle to a horizontal reference greater than zero degrees, said lumen having a first known dimension; a flow restrictor having an inlet and an outlet, said inlet being in fluid communication with said second end and wherein said outlet is arranged to deliver any fluid that passes therethrough to a collector, said flow restrictor including some known dimensions; said lumen and said flow restrictor being initially occupied by a continuous, non-moving sample of fluid therein; a sensor for detecting the movement of the fluid over time once the sample of fluid begins moving and passes from said outlet into said collector, said sensor generating data relating to the movement of the fluid over time; said first end being exposed to atmospheric pressure creating a pressure differential between said first end and said outlet, said sample of fluid moving through said lumen and said flow restrictor at a first shear rate caused by said pressure differential, said movement of fluid causing said pressure differential to decrease from said first shear rate for generating said plural shear rates; and a computer, coupled to said sensor, for calculating the viscosity of the fluid based on said data relating to the movement of the fluid over time, said first known dimension of said lumen and said some known dimensions of said flow restrictor.