Linkage steering device of semitrailer

The utility model discloses a semitrailer linkage steering device which comprises a traction vehicle head and a semitrailer body connected with the traction vehicle head, a control switch is arranged in a cab of the traction vehicle head, a vertical plate is welded to the bottom of the semitrailer body, a cross beam is welded to the bottom end of the vertical plate, and U-shaped frames are welded to the two ends of the cross beam. The driving motor is started to enable the output end of the driving motor to rotate forwards or reversely to drive the transmission shaft and the worm to rotate synchronously, drive the worm gear meshed with the worm to rotate and drive the steering shaft and the fixing frame to rotate synchronously, and kinetic energy is transmitted to the L-shaped connector through the transmission assembly to enable the L-shaped connector to rotate. Therefore, a driver can rotate the rear steering wheel of the semitrailer to a proper angle according to needs, the steering direction of the rear s