Patent ID: 6701791
Filing Date: 2004-03-09
Classification: G01L

Abstract:
An interchangeable module for use in a piston-cylinder pressure measurement device, comprising:(a) a cylinder having an outer surface and a bore extending through the cylinder; (b) an elongated piston vertically movable in the bore, the piston receiving a downward calibration force; (c) a housing for supporting the cylinder, the housing including one of a lower portion engaging both a bottom portion of the cylinder and a lower peripheral portion of the cylinder and an upper portion engaging an upper peripheral portion of the cylinder; (d) a cover engaging a top portion of the cylinder, the cover, an inner portion of the housing, and a portion of the outer surface of the cylinder forming an internal volume; and (e) a first passage extending from an upper portion of the internal volume to an inlet opening of the interchangeable module to pressurize the internal volume at a pressure of a fluid to be measured, and a second passage extending from the internal volume through a wall of the cylinder into the bore to conduct pressurized fluid into a gap between the piston and the bore.