DIFFERENTIAL PRESSURE SENSOR

摘要

A pressure sensing device is disclosed having the pressure sensing diaphragm positioned in a housing which is not stressed or enlarged by large static pressure. The housing is attached within a recess of a larger casing by means of a support diaphragm. The recesses are communicated with the interior of the housing by passages therethrough to equalize the pressure inside and outside the housing. The outer side of each casing forms a pressure reception chamber with a respective pressure receiving diaphragm. The latter chambers communicate with the recess via passages in the casing. The space between the pressure sensitive diaphragm and each pressure receiving diaphragm, including the housing interior chamber, the housing passage, the casing recess, the casing passage and the pressure receptive chamber, is filled with a fluid. The construction and filling is such that overpressure on one pressure receiving diaphragm causes the entire housing to move toward the inner wall of the casing. However the latter diaphragm closes with the outer wall of the casing before the housing contacts the casing inner wall.