| 摘要 |
PURPOSE:To improve measuring accuracy, by imparting resiliency to a spring by attracting a movable iron core, imparting straight motion to the movable iron core by the resiliency of the spring, and detecting a vibrating force by a force detecting sensor that is connected to the movable iron core directly. CONSTITUTION:When a DC voltage is imparted to a winding 14 through a power source cable 24, a looseness-diagnosing vibration-applying device becomes a DC electromagnet, and magnetic flux is generated. A movable iron core 16 is attracted to a fixed iron core 15 by the magnetic attracting force. By the attraction of the movable iron core 16, a compressing coil spring 17 is compressed and keeps resiliency owing to the compression. When the DC power source is cut OFF, the compression is instantaneously released, and straight motion is imparted to the movable iron core 16. Then an impact is given to a member to be diagnosed. A vibrating force is detected by a force detecting sensor 20 that is directly connected to the movable iron core 16. The vibration from the member to be diagnosed is detected by an acceleration sensor 23. By computing the ratio between the vibrating force and the vibration, looseness can be accurately measured. |
