To provide a friction-driven truck carriage device having a selectively controllable carrying pitch without changing the length of a truck.

A truck travel rail 11 for a truck 10, on which carried objects are loaded, to travel and a bar travel rail 21 located along the rail for a conveyor bar 20 to travel are placed. A bar driving device 24A is provided in a carriage starting area CS for driving a plurality of continuous conveyor bars 20 to travel with the rotational drive of a driving wheel 23 friction-engaged with a bar side face 201 of the conveyor bar 20 at the most upstream side. The truck 10 is provided with a bar clamp 13A for detachably clamping the bar side faces 201 of the conveyor bar 20 at random positions on both sides and connecting the truck 10 to the conveyor bar 20.