원래 이름 기록: KABUSHIKI KAISHA TOKAI RIKA DENKI SEISAKUSHO

A sensor device includes: an acceleration sensor that rotates in conjunction with rotation of a nut that fastens a wheel hub to a wheel rim and detects an acceleration along a detection axis that intersects with a rotation axis of the wheel rim; and a signal processor that detects a fastening state of the nut based on the acceleration detected by the acceleration sensor.

A sensor device includes an acceleration sensor that detects an X-axis acceleration and a Y-axis acceleration. The sensor device further includes a signal processor that detects a fastening state of each nut based on a comparison result between a rotation angle of the sensor device calculated based on the X-axis acceleration and the Y-axis acceleration and an initial rotation angle of the sensor device calculated based on an initial value of each of the X-axis acceleration and the Y-axis acceleration. After each of the X-axis acceleration and the Y-axis acceleration becomes equal to a value that can be regarded as a zero value, the signal processor defines an acceleration which is detected by the acceleration sensor and is greater than the zero value as an initial acceleration.