Abstract: The useful range of the disclosed pressure transducers is extended by isolating the sensing means of the transducer from bending moments produced in the transducer body by the fluid pressure being measured. The isolating means may comprise an isolating ring interposed between the body and the sensor means, disposed behind a diaphragm which is attached to the isolating ring and the body. The isolating ring is connected to the body by means adapted to hold the sensor means in an established relationship with the diaphragm while being of a character to avoid transmitting bending moments, whereby the isolating ring and the sensor means are isolated from bending moments developed in the body due to fluid pressure.

Abstract: The pressure of a fluid, flowing along a passage, is accurately measured by a flush pressure transducer, including substantially flat diaphragm means forming a smooth continuous wall of the passage, a body backing up and supporting the diaphragm means, the body having an opening therein, the diaphragm means covering such opening and affording a flexible resilient diaphragm across such opening, and sensor means operable by the diaphragm for sensing any deflection of the diaphragm due to any fluid pressure against the diaphragm. The diaphragm means may comprise a substantially flat sheet mounted against the body and extending across the opening, preferably with bonding means between such sheet and the body. Alternatively, the diaphragm means may be integral with the body. A temperature sensor may be mounted behind the diaphragm means and in a second opening in the body. The pressure sensor may afford a variable capacitance between capacitor electrodes in the first mentioned opening and on the diaphragm.