| 摘要 |
A differential variable capacitance acceleration sensor includes a sandwich structure having three stacked plates of silicon with the center plate mounted such that its center portion is enables to move in a sealed cavity with each side thereof moving toward and away from a fixed cooperating plate forming the opposite side of a capacitive circuit. The center portion or mass of the center plate is suspended from its rim by means of a large number of integral fingers extending from the rim to the top and bottom surfaces of the center portion. This center mass includes a number of through holes to permit the passage of air from one side to the other and may also include grooves to aid in the flow of air. The fixed top plate or lid and the base also have, or may have, grooves to assist in the passage of air. The integral fingers are formed in sinuous curves or other form varying from straightness but having a significant tension such that when the center mass is displaced during a sensed acceleration, the fingers tend toward straightness. In an alternative embodiment, the fingers are bars having corrugations stepped between different planes.
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