Pressure/temperature transducer with improved thermal coupling and

Abstract

A transducer pressure crystal having improved thermal coupling with the environment external to a pressure housing in which the crystal is disposed. A cylindrical major portion of the side wall of the pressure crystal is located immediately adjacent an inner wall of a chamber within the pressure housing, separated therefrom only by dimensional tolerances sufficient to ensure that the crystal is surrounded by pressure-transmitting fluid exposed to pressure from the external environment. The thermal time constant of the transducer for external temperature changes is significantly decreased. The time constant of the transducer for temperature changes in the pressure-transmitting fluid produced by rapid pressure changes is similarly decreased. A thin, electrically insulating element may optionally be disposed between the crystal side wall and the inner wall to preclude electrical grounding of the crystal to the housing. The electrically insulating element may comprise a discrete film, such as a high temperature plastic, or an insulating layer on the inner wall of the pressure housing. Various embodiments of the present invention are disclosed, including different crystal and interior pressure housing configurations. In one embodiment, both pressure and temperature crystals are deployed in the fluid-filled chamber.