Multi-stage grinding device for superfine powder

The utility model discloses a multi-stage grinding device for superfine powder. The multi-stage grinding device comprises an outer cavity and an upper cover locked at the top of the outer cavity, the rotating motor is locked at the top of the upper cover and inserted into the outer cavity; the millstone structures are fixed on the peripheral surface of the output shaft of the rotating motor, each millstone structure comprises a plurality of fixed millstones which are nested on the output shaft of the rotating motor and are arranged at intervals, and the fixed millstones are movably connected with the output shaft of the rotating motor through a bearing; the movable millstones are alternately arranged between the two fixed millstones, and the movable millstones are fixedly locked on an output shaft of the rotating motor; and the discharging end is arranged at the bottom of the outer cavity, multi-stage grinding can be achieved only in one cavity, mineral powder does not need to be transferred for multiple time