PURPOSE: To install an intermediate frame at a low cost in spite of lateral movement by providing a rod connected to an intermediate frame to control its lateral movement, and guiding the ends of the rod to vehicle sections.

CONSTITUTION: The lateral movement of an intermediate shackle 15 is controlled using a flexible rod 40, the ends of which are longitudinally shiftable by shift bearings 41 fixedly arranged at front faces 13 of vehicle sections 1, 2. An intermediate frame 20 is connected to an intermediate part of the rod 40 being longitudinally fixed at a fixed angle. When turning motion between the vehicles is made around a longitudinal axis in a lateral direction to an intermediate face, and the ends of the flexible rod 40 in the direction of longitudinal shafts 42, 43 of the vehicle sections 1, 2 are fixed, the rod 40 is curved corresponding to a desired curve at other points, and in this case, a connection part 44 to the frame 20 is suitably moved in the lateral direction. The intermediate frame 20 is therefore moved corresponding to the curve of the rod 40, and an awning 12 also follows the curve.