Transmission and sealing structure of steering drive axle

The utility model belongs to the technical field of steering driving devices, and particularly relates to a transmission and sealing structure of a steering drive axle, a differential mechanism half axle gear in a main reduction gearbox shell is connected with a half axle, a half axle shell is connected with a steering knuckle shell, the steering knuckle shell is connected with a hub reduction gear and a hub, and a universal transmission shaft is arranged in the half axle shell and the steering knuckle shell in a penetrating mode. The universal shaft long fork shaft is connected with the half shaft, the universal shaft long fork shaft and the universal shaft short fork are connected with the duplex fork, a sun gear shaft is rotationally installed on a planetary gear carrier of the hub reduction gear, the sun gear shaft is connected with the universal shaft short fork through an inner spline and an outer spline, and an O-shaped ring is arranged between the bearing seat and a half shaft shell. Muddy water preve