PURPOSE: To fix and support a moving device in state where it is off-centered with respect to the inside diameter of a pipe by journalling one end of each of a pair of arms having expansion mechanisms to the moving device, and journalling the other ends of the srms integrally to each other.
CONSTITUTION: Truck-side supporting points of arms 7a, 7b having right and left fixing expansion mechanisms 1a, 1b are rotatably supported on a moving truck 5 by pins 2a, 2b respectively. Further, the tips of the arms are rotatably connected to a contact pad 4 by pin 3. As a result, a fixing-supporting mechanism through a three-node link consisting of the truck 5 and the arms 7a, 7b having the fixing expansion mechanisms 1a, 1b, is formed. The fixing-supporting mechanism is moved by its wheels 6a, 6b in the axial direction in a pipe 20 with the right and left fixing expansion mechanisms 1a, 1b being contracted (in state indicated by solid lines in figure) up to a work place, and when a specified place is reached, the fixing expansion mechanisms 1a, 1b are synchronized with each other to be expanded to allow the contact pad 4 on the tips of the arms to abut on the inner surface of the pipe 20 at the position just above the moving truck. Then a specified work in the pipe is performed.
SUMI MASANOBU
FUKUCHI HIROSHI
