| 摘要 |
PROBLEM TO BE SOLVED: To measure plate thickness without being affected by the inclination and measuring posture of an ultrasonic probe by arranging multiple array vibrators on the inner peripheral face of a tire. SOLUTION: Signals from multiple array vibrators 2a, 2b... arranged on the periphery of a tire 1 are received via a channel switching device 9. One or multiple array vibrators, e.g. 2b, 2c, 2d having a high gain are selected by the channel switching device 9 for measurement. When the array vibrators 2 are electronically switched in the peripheral direction in sequence to measure plate thickness, the measured results of the array vibrators not kept in the direction perpendicular to a body under inspection can be eliminated, the best detected value of the array vibrator 2 kept in the perpendicular direction is obtained, and the most accurate measured data can be obtained. When multiple vibrators 2, e.g. 2a, 2b, 2c, are concurrently driven, the transmitted and received ultrasonic waves 5 have wider directivity than that of a planar vibrator due to spherical radiation, and the effect of the inclination of the body 6 under inspection is reduced. |
