Abstract: A differential pressure transducer having a central support structure separating two flexible diaphragms. The support structure has a central hole and the diaphragms are joined on their opposing surfaces at their respective centers by a post that is loosely received through the hole. The central structure and each diaphragm are separated by an annular sealing ring that is preferably fabricated from a glass frit having characteristics similar to the material used for the diaphragms and central structure. The transducer further includes a plurality of electrodes located on one surface of the central support member and a third electrode, located on the inner surface of one of the diaphragms, therein forming the electrodes of a pressure sensing capacitor and a reference capacitor.

Abstract: Apparatus for rapidly generating highly accurate pressures for testing pressure responsive equipment such as may be used for aircraft control purposes. The apparatus may be used in an airborne mode or in a shop or repair depot. Highly accurate pressures are dependably and consistently provided for the aforenoted testing purposes by providing a system having interfacing digital, analog and pneumatic sections.