| 摘要 |
A differential pressure-transducer of the capacitive type that includes a drum-shaped insulating body whose flat opposing faces each have a circular back-up nest indented therein covered by an insulating diaphragm to define a cavity. The underside of each diaphragm is metallized as is the base of the related nest to form the electrodes of a variable capacitor whose value depends on the degree and direction of diaphragm deflection. Interconnecting the cavities is a plurality of internal ducts of small diameter that extend between the bases of the nests. Admitted through one of the ducts and filling the cavities is an incompressible dielectric fluid. Hence when an increase in high pressure applied to the face of one diaphragm acts to deflect this diaphragm inwardly, the fluid in the related nest is forced through the ducts into the nest for the low pressure diaphragm which is then deflected outwardly. Because the combined diameter of the ducts is relatively large, the resultant flow path is substantially unrestricted and the time constant of the transducer is short. And even when the diaphragm is deflected inwardly to an extent causing it to abut the base of the related back-up nest and to block one or more of the ducts, the remaining ducts remain free and prevent latching of the diaphragm caused by vacuum effects or surface tension of the fluid.
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