| 摘要 |
PURPOSE:To obtain a device of contactless system with good power efficiency, by performing electric discharge between a rotating disc coated with a metallic film and a discharge needle installed to a dynamic pressure float in response to signals, and changing the electric capacitance through the removal of the metallic film. CONSTITUTION:A dynamic pressure float 1 is supported with a linear feeder 3 via a supporting elastic member 6 and is moved in the direction B orthogonal to the direction A, on a disc 2 made of polyvinyl chloride or acrylic resin, coated with a metallic film 7 and rotated toward the direction A. The float 1 has a groove 1' at the bottom and a discharge needle 4 with a prescribed inteval to the disc 2, and a voltage is appled from a fly lead 5 in response to signals, and the metallic film 7 is removed through the discharge with the disc 2 to change the electric capacitance. The float 1 is floated with an air flow generated with the rotation of the disc. At reproduction, readout is done through the change in the resonane frequency due to the capacitance change of a resonance circuit (not shown). Thus, the contactless device of capacitance change system with excellent power efficiency can be obtained. |
