Patent ID: 7481114
Filing Date: 2009-01-27
Classification: G01N

Abstract:
1. An apparatus for determining a characteristic of a fluid in a tube, the tube including a tube wall, the tube wall including a first wall region and a second wall region, the apparatus comprising: (a) means for applying a force to cause a change in a transverse dimension of a segment of the tube, wherein the change in the transverse dimension is reversible; and (b) means for launching and receiving ultrasonic signals, wherein the means for launching and receiving ultrasonic signals comprises a single transducer, wherein a first ultrasonic signal propagates along a first path through the tube, the first path having a first path length, and a second ultrasonic signal propagates along a second path through the tube, the second path having a second path length, and wherein the first path length differs from the second path length and at least one of the first path and the second path is located entirely within the segment; wherein the first path and the second path are colinear; wherein the first path is orthogonal to the tube wall and the second path is orthogonal to the tube wall; wherein the first wall region is adjacent the single transducer; wherein each of the first ultrasonic signal and the second ultrasonic signal propagates through the tube wall in the first wall region and reflects from an inner surface of the second wall region.