| 摘要 |
A washer assembly (20) is for use with a fastener (10). The washer assembly includes a first conductive portion (22), a second conductive portion (24), and an insulating portion (23) disposed between the first conductive portion and the second conductive portion. The first conductive portion, the second conductive portion, and the insulating portion form a variable capacitor (21) having a capacitance based on an amount of force applied thereto by the fastener. A wireless transponder unit (25) includes a control unit (40) electrically connected to the variable capacitor and an antenna (41) electrically connected to the control unit. The control unit is configured to sense the capacitance of the variable capacitor, to generate information representing the capacitance, and to output the information to a wireless reader unit via the antenna. |
