Patent ID: 8220336
Filing Date: 2012-07-17
Classification: G01H

Abstract:
1. A servo-type vibration detector comprising: a pendulum supported by a fixed member and displaceable by external vibration; a movable electrode affixed to the pendulum; a driver configured to drive the pendulum; a fixed electrode positioned opposite the movable electrode; an electrostatic capacitance detector configured to detect an electrostatic capacitance between the movable electrode and the fixed electrode; a current supplier configured to supply a current to the driver in an amount associated with a detection result of the electrostatic capacitance detector, such that the pendulum is displaced and driven to a predetermined neutral position; a detection signal outputter configured to output a detection signal associated with the amount of the current supplied by the current supplier; a remover configured to remove a charge between the electrodes, when the movable electrode and the fixed electrode contact each other; and an electrode contact determinator configured to determine an electrode contact by detecting that the detection signal output from the detection signal outputter changes to a detection signal associated with the current supplied from the current supplier in an amount associated with the removed charge, wherein the electrode contact determinator determines the electrode contact when a predetermined determination time elapses in a detection state, after detecting the change to the detection signal associated with the current supplied from the current supplier in the amount associated with the removed charge.