Hydraulic multi-disc brake and mechanical device comprising such brake

The utility model discloses a hydraulic multi-piece brake which comprises a brake shell, and a brake piece, a brake piston, a spring limiting part, a spring, a brake gasket and a retaining ring which are sequentially mounted in the brake shell along the axial direction when the hydraulic multi-piece brake is assembled, the spring limiting part is provided with a receiving part for accommodating the spring and is arranged between the brake piston and the brake gasket; the brake gasket is arranged next to the spring limiting part and is configured to enable the spring to be kept in the receiving part in a pre-compression manner between the brake piston and the brake gasket; the retaining ring is configured to engage with the brake housing and abut against the brake washer to ensure compression retention of the spring, characterized in that the brake washer and the brake piston further comprise additional securing structures configured to ensure relative securing of the brake piston and the brake washer and comp