| 摘要 |
PURPOSE: To obtain an ultrasonic inspection system in which a microdefect having diameter as small as 0.15mm can be detected using a plate wave. CONSTITUTION: An oscillator 5 disposed, while inclining, in a rubber tire 3 oscillates an ultrasonic beam 37 which enters into a thin metal plate 31 to generate a plate wave 33 therein. A defect 35 is detected based on the plate wave 33 reflected on the defect 35 and returning back to the oscillator 5. Detection of microdefect depends on the frequency of the ultrasonic beam 37 which is a sine burst in the invention. With such arrangement, selectivity of frequency can be enhanced and the frequency can be regulated easily to fit an objective defect. Furthermore, since a sine burst is employed, ultrasonic output can be enhanced without requiring significant power as compared with a single pulse and a relatively large reflection wave can be received even from a small defect. |
