PURPOSE: To make it possible to obtain a large pressing stroke, by mounting a valve for controlling the escape amount of a fluid corresponding to the contraction and expansion stroke of a cylinder contractable and expandable in a multi- stage and a gimbal mechanism for connecting a probe to the cylinder and allowing the same to follow the surface of an object to be inspected.

CONSTITUTION: The titled apparatus is constituted of a track 23 attached to an arranged pipe 10, a scanning apparatus 20 moving along said track 23 to a peripheral direction, a holder 18 moving to an axial direction in engaged relation to an arm 21 and a screw 22, a probe 19 and the pressing part 28 of said probe 19. A motor is mounted in the scanning apparatus 20 and rotates the pinion meshed with the rack of the track 23 to scan the probe 19 to the peripheral direction along the track 23. In addition, a separate motor is provided to the scanning apparatus 20 and the screw 22 is rotated to scan the probe 19 to the axial direction along the arm 21.