PURPOSE: To provide a highly reliable differential manometer in which dust is removed and abnormal function is prevented at the sensor part while reducing the manufacturing cost.
CONSTITUTION: The differential manometer comprising a metal housing encapsulating a liquid and a semiconductor measuring diaphragm further comprises a planar silicon substrate 21, first and second glass substrates 22, 23 sandwiching the silicon substrate 21, first and second measuring chambers 24, 25 disposed oppositely to the opposite sides of the silicon substrate 21 and defining a measuring diaphragm 26 thereof, a first filter section 27 comprising a plurality of meshed etching grooves made in the silicon substrate 21 or the first glass substrate 22 constituting first through holes communicating the first measuring chamber 24 and the outside, and a second filter section 28 comprising a plurality of meshed etching grooves made in the silicon substrate 21 or the second glass substrate 23 constituting second through holes communicating the second measuring chamber 25 and the outside.
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