PURPOSE: To provide a shifting device which can cope with a variety of environments, by a single unit having the simple fundamental structure.

CONSTITUTION: A shifting device 100 is equipped with a plurality of shifting mechanisms 2a, 2b and 2c, connecting parts 4 and 5 arranged between the shifting mechanisms 2a, 2b and 2c, and joints 28 and 31 which are rotatable and connect the shifting mechanisms 2a, 2b and 2c and the connection parts 4 and 5. The connection part 4 is formed from a flexible member such as a closely attached coil spring. With such the constitution, the position relation of the shifting mechanisms 2a, 2b, and 2c changes automatically by the deformation of the connection part 4 and the revolution of the joints 28 and 31, and easy intrusion into a narrow place is enabled. Further, in the narrow place such as in a pipe, the connection part 4 deflects, and the shifting mechanisms 2a and 2b deform so as to be set along the wall surface, and the restoration force due to the deflection is received, and the sufficient abrasion for the wall surface is secured, and the sure traveling operation can be realized.