IMPROVED GAUGE HIGH PRESSURE SENSOR
Original Publication Date: 1983-Mar-01
Included in the Prior Art Database: 2001-Oct-09
An improved gauge (differential ambient to unknown) high pressure sensor is disclosed which comprises a heavy metallic diaphragm assembled directly to an upper metallic housing and held in place by a sealing 0 ring and a lower metallic housing. The diaphragm and housing configuration are preferably as shown in the Figure which illustrates a cross section of the present sensor. The diaphragm acts as a displaceable first capacitive electrode and a second fixed posltion capacitive elec- trode is mounted on a lightweight insulating cap. The second electrode output lead is coupled to the second electrode through a primary channel in the insulating cap, and the primary channel and a secon- dary channel provide a pressure path such that ambient pressure will be present in a first cavity formed between the upper housing and the diaphragm with this cavity preferably maintaining ambient pressure. An unknown pressure is applied to a second cavity in the sensor through a pressure inlet and results In predetermined deflection of the diaphragm such that the capacitance between the elec- trodes is altered in accordance with the differential pressure difference between the pressures in cavities I and II.