Solid state differential pressure sensor with overpressure stop and free edge construction
AssigneeRosemount Inc.
InventorsThomas A. Knecht, Ahmed Naumaan, Stanley E. Rud, Jr.
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AssigneeRosemount Inc.
InventorsThomas A. Knecht, Ahmed Naumaan, Stanley E. Rud, Jr.
Estimating the term…
A solid state pressure sensor utilizes a brittle diaphragm made of a material such as silicon, which is mounted between base plates of glass, and which deflects in response to pressure. The base plates of glass can have recesses formed therein to receive the diaphragm and provide a full support across the diaphragm under overpressure conditions to prevent overstressing the diaphragm, or the diaphragm can have such contoured surfaces for forming overpressure stop surfaces against the facing base plate. The diaphragm has grooves defining a central portion that deflects, and whereby the grooves will form webs joining the central portion to an outer rim so that the diaphragm acts similarly to a "free edge" diaphragm in its deflection characteristics. The grooves defining the webs can have various configurations for achieving the results desired.
A differential pressure sensor cell comprising a brittle material diaphragm member having a desired thickness:
A pressure sensor diaphragm for mounting between two base plates made of brittle material relative to which the diaphragm deflects under pressure differentials, said diaphragm comprising a brittle material and being generally planar in shape, and having a thickness and a peripheral edge, groove means defined in said diaphragm to extend inwardly from at least one surface thereof to define a narrow web means extending between an outer rim portion of the diaphragm and an inner center portion of the diaphragm formed by said groove means, said rim portion being supported on at least one base plate during use, said diaphragm and web means having dimensions such that when a high pressure is applied to at least one side of said diaphragm to cause the center portion to deflect the stress levels in a base plate on which the diaphragm is supported and in the web means of such diaphragm reach their respective operating stress level at substantially the same pressure.
A differential pressure sensor cell comprising a brittle material diaphragm member having a desired thickness;
Dependencies are inferred from the claim text.