| 摘要 |
A vibration sensor unit (100) includes a metal casing (11), a vibration sensor (12) disposed in the casing (11), a battery (15), and a control unit (13). The control unit (13) applies power supplied from the battery (15) to the casing (11) to apply charges to the casing (11), and controls an amount of power applied to the casing (11). |
