Maintenance-free structure for camshaft of brake

The utility model discloses a brake camshaft maintenance-free structure which comprises a camshaft, a brake bottom plate and an air chamber support, the brake bottom plate and the air chamber support are both connected to the camshaft in a sleeved mode, and the brake bottom plate and the air chamber support are connected with the camshaft through abrasion-resistant assemblies respectively. The sides, away from each other, of the two wear-resisting assemblies are each provided with a one-way oil seal, openings of the two one-way oil seals are arranged in a back-to-back mode, and the openings of the two one-way oil seals are both arranged outwards. The one-way oil seals, the wear-resistant assemblies and the spacer bushes are arranged at the two ends of the cam shaft, the functions of external dust prevention and internal lubricating grease overflow prevention are achieved, meanwhile, the working reliability of the brake cam shaft is greatly improved, and therefore it is guaranteed that the brake cam shaft has