Automatic medicine polishing device

The invention discloses an automatic pounding device which comprises a mortar body, a cover body covering the mortar body and a pounding rod penetrating through the cover body, an inner cylinder is further arranged in the mortar body, the pounding rod is located in the inner cylinder, the top end of the inner cylinder is provided with a circle of lap edge protruding outwards, a circle of annular groove is formed in the position, corresponding to the lap edge, of an upper end opening of the mortar body in a concave mode, and the lap edge is pressed in the annular groove through the cover body. A boss is arranged in the middle of the bottom of the mortar body, a pounding groove for pounding the medicine is formed in the middle of the boss corresponding to the pounding rod, and the bottom end of the inner cylinder just abuts against the boss, so that the medicine needing to be pounded is surrounded in a space defined by the cover body, the inner cylinder and the boss; the bottom of the inner cylinder is closed,