US Patent 7096738 In-line annular seal-based pressure device

A pressure sensor for measuring a pressure of a process fluid includes a vessel, an electrode and a diaphragm. The vessel receives the process fluid. The electrode is integral with an inner wall of the vessel. The diaphragm extends at least partially over the electrode and is configured to move relative to the electrode in response to the pressure of the process fluid. An electrical capacitance between the electrode and the diaphragm is related to the pressure of the process fluid.