Electrostatic capacity-type pressure sensor

An electrostatic capacity-type pressure sensor comprising:

• a diaphragm support body formed into a tube shape;
• first and second lids made of an insulating material and each having a thin diaphragm portion, said first and second lids each having a thick fixing portion formed integrally with peripheral edge portions of said diaphragm portions and arranged to face each other by bringing said thick fixing portions in tight contact with two end portions of said diaphragm support body, said first and second lids separating an interior of said diaphragm support body from the outside by closing said two end portions of said diaphragm support body;
• a first fixed electrode formed directly on an inner surface of said thick fixing portion of said first lid;
• a second fixed electrode formed on an inner surface of said thick fixing portion of said second lid;
• a coupling member having two ends connected to said first and second lids to couple said diaphragm portions facing each other;
• an electrode support member supported by said coupling member and arranged between said first and second lids at a predetermined interval;
• a first movable electrode formed on said electrode support member facing said first fixed electrode, said first movable electrode and said first fixed electrode being arranged parallel to each other at a predetermined interval to constitute a first capacitor;
• and
• a second movable electrode formed on said electrode support member facing said second fixed electrode, said second moveable electrode and said second fixed electrode being arranged parallel to each other at a predetermined interval to constitute a second capacitor. electrode is aligned substantially flush with said thin diaphragm portion.
• a second movable electrode formed on said electrode support member so as to face said second fixed electrode, said second movable electrode and said second fixed electrode being arranged parallel to each other at a predetermined interval to constitute a second capacitor.