| 摘要 |
PURPOSE:To detect a defect of an object with the shape of curvature accurately, by providing a receiving vibrator at the center of a lens and a pair of transmitting vibrators on the side thereof while an ultrasonic wave transmitting/receiving surface of the lens is made the same in the curvature as the object being inspected. CONSTITUTION:A lens 2 is housed at the bottom of a cylindrical case 1 and the surface of the lens is made equal in the curvature to the surface of an object to be inspected. A receiving vibrator 5 is provided at the center 2a of the lens 2 to receive ultrasonic waves. Surfaces 2b and 2c are formed on the side of the vibrator 5 in inclination from the center line of the lens 2 and transmitting vibrators 3 and 4 are provided on the surfaces to generate an ultrasonic wave so that the ultrasonic waves generated is made to cross one another right under the receiving vibrator 5. The convex surface of the lens 2 is put so tight on the surface of the object being inspected as to prevent the formation of an air layer thereon and then a flaw detection is performed. The arrangement of a plurality of transmitting vibrators 3 and 4 enables the discovery of a fine defect by amplifying reflected waves from the defect. Thus, as the curvature of the ultrasonic transmitting/receiving surface of the lens is made coincident with that of the object being inspected, a defect in a member with the shape of curvature can be detected at a high accuracy.
|
