| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an external force detector capable of precisely and easily detecting an external force applied to a piezoelectric piece. <P>SOLUTION: A quartz piece 2 is supported in a cantilever manner in a case 1. The quartz piece 2 has excitation electrodes 31 and 41 each formed on an upper surface and a lower surface at, for example, a central area. The quartz piece 2 has a movable electrode 5 formed in a front end portion at the lower surface side, which is connected to an excitation electrode 41 located at the lower surface side via an extraction electrode 42. The case 1 has a fixed electrode 6 formed on the bottom opposite the movable electrode 5. The excitation electrode 31 at the upper surface side and the fixed electrode 6 are connected to an oscillation circuit 14. When the quartz piece 2 deflects due to an external force applied thereto, the capacitance between the movable electrode 5 and the fixed electrode 6 varies. The variation of the capacitance is read as a variation of oscillation frequency of the quartz piece. <P>COPYRIGHT: (C)2013,JPO&INPIT |
