Rail running bearing truck

The utility model relates to a rail running bearing truck, which comprises a ring-shaped rail and a bearing truck, wherein the ring-shaped rail is provided with a flat bottom, two sides of the rail are provided with ribs, a loading mechanism is arranged on a holding board of the bearing truck through a revolving shaft sleeve, a running wheel and a guide wheel are mounted below the holding board through a bracket shaft sleeve and a wheel bracket, the running wheel fixed on the wheel bracket through a wheel shaft rotates around the wheel shaft and swings around a rotary shaft of the wheel bracket, the wheel bracket rotates inside the bracket shaft sleeve, the rotatable guide wheel is disposed on the bracket shaft sleeve and contacts with the ribs of the rail, the wheel bracket and the bracket shaft sleeve are in clearance engagement, and the rotating range of the wheel bracket is controlled within a range lower than 90 degrees through a limiting pin fixed on the wheel bracket and a groove fixed at the end porti