Main adjusting structure of clearance self-adjusting mechanism in disc brake

The invention provides a main adjusting structure of a clearance self-adjusting mechanism in a disc brake, and belongs to the technical field of automobile parts. The problem of insufficient working stability is solved. The main adjusting structure comprises a main adjusting shaft assembly, a return spring and an adjusting assembly connected to the main adjusting shaft assembly in a sleeving manner; an abutting seat is arranged at the lower side of the adjusting assembly, and two ends of the return spring act on the abutting seat and a brake mechanism in the disc brake respectively; the adjusting assembly can be in contact with the main adjusting shaft assembly under the action of the return spring and achieve circumferential transmission in a friction manner; the main adjusting shaft assembly is further sleeved with an elastic connecting part; the inner side wall of the connecting part is in contact with the main adjusting shaft assembly all the time under the action of the elastic force of the connecting pa