| 摘要 |
A variable capacitor for use in a keyboard comprises a stationary capacitor plate of thin, conductive, sheet material on an insulative substrate and having a substantially planar face. A movable member formed from a single piece of conductive sheet material includes a movable capacitor plate having a substantially planar, and continuous face in overlaying spaced apart relation to the stationary plate. The movable plate is struck from the body of a short length of a strip of sheet material to provide a pair of longitudinal side edges and an outer free edge transverse thereto, with a portion opposite the free outer edge projecting laterally outward and integral with a pair of supporting, spring-like, deflectable legs which extend downwardly toward the substrate to join an integral base strip mounted on the substrate. The legs support the movable capacitor plate above the stationary capacitor plate for controlled movement about a lateral pivot axis toward and away from the stationary plate to vary the capacity of the capacitance. A separate, washer-like element is mounted above the movable capacitor plate for engagement therewith and is supported on a plunger mounted for longitudinal movement on an axis normal to the substrate. The plunger is biased away from the movable capacitor plate and is adapted to move the washer-like element toward the capacitor plate to increase capacitance in response to the manual depression of a key or push button on a keyboard or the like above the substrate.
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