| 摘要 |
PURPOSE:To provide large Q damping amount, reduced dispersion in a resonant frequency, and easy adjustment of the resonant frequency, to prevent short circuit, and to make the wire breakdown hard to occur, by attaching piezoelectric ceramic material to both sides of a metal vibrating plate wherein two or more holes are formed so that the polarities of the ceramic materials are directed in the same direction, and electrically connecting the ceramic materials in parallel. CONSTITUTION:Two sheets of the piezoelectric ceramic materials 10a and 10b are connected in parallel. Then the electrostatic capacity is doubled and the Q damping amount can be increased. When the thickness of the ceramic material is made thin, the electrostatic capacity is further increased. Since the resonant frequency is determined by the interval between the holes 9a and 9b, the dispersion in the resonant frequency becomes small. The diameters of the holes 9a and 9b are changed when the resonant frequency is adjusted. Therefore the short circuit due to flash can be prevented. Connected area is made large by providing metal foils 13 and 14 on silver electrodes 11 and 12. Therefore thin wires 15 and 16 do not become small because of the heat that is yielded when the thin wire 15 and 16 are soldered to the metal foils 13 and 14. Therefore the wire breakdown does not occur. A numeral 19 denotes a resistor, whose one end is connected to a substrate 17. The other end thereof is connected to the thin wires 15 and 16. |
