Third-series axle assembly

The utility model discloses a third-series axle assembly. The axle assembly comprises an axle head, an axle body, a hub and a brake drum, wherein the hub and the brake drum are connected and installed on the axle head; one end of a brake shoe is connected with a pin shaft inside a supporting pin hole; a cam shaft penetrates through a cam shaft installation hole and is contacted with a brake shoe roller at a free end of the brake shoe; inner and outer bearings are installed between the axle head and the hub and fixed through an axle head nut; a lock washer is arranged on one side of the axle head nut; the inner and outer bearings are arranged on one side of the lock washer; a groove cavity penetrating through the whole axle head nut and a pin shaft inserted in the groove cavity are arranged on the axle head nut; the pin shaft is sleeved with a pressure spring; the pressure spring is arranged inside the groove cavity, and one end of the pressure spring abuts against a flange of the pin shaft; and multiple holes