| 摘要 |
<p>A capacitive pressure sensor (10) comprises: a housing (12) including first and second spaced apart diaphragms (114, 116), matched in compliance to vibrate and deflect in substantial unison in response to vibratory and acceleration forces; said first diaphragm (114) being an outer pressure responsive diaphragm, movably cooperating with said housing to bound a reference-pressure chamber (106, 108) within which is movably disposed said second diaphragm (116), which carries on its surface facing said first diaphragm (114) a first pair of spaced apart planar electrodes (52, 54) each having a predetermined geometric shape, and a first planar shield electrode (56) having a portion (58) circumscribing said first pair of electrodes (52, 54) and a cross bar portion (60) interposing between said first pair of electrodes; said first diaphragm (114) carrying on its surface facing said second diaphragm (116) a second pair of spaced apart planar electrodes (92, 94) each having said predetermined geometric shape; said first pair of electrodes (52, 54) and said second pair of electrodes (92, 94) being congruent to define a respective pair of variable capacitors, having substantially identical value and varying in capacitance value simultaneously in union as said first diaphragm (114) moves in response to external fluid pressure, whereby said variable capacitors remain of substantially identical value in response to external fluid pressure acting on said sensor, and said capacitance values being substantially immune from said vibration and acceleration forces.</p> |
