External circulation extraction device

The utility model relates to an external circulation extraction device which comprises a supporting seat, an extraction tank is fixedly mounted at the top of the supporting seat, a filter plate is fixedly mounted on the inner wall of a cavity of the extraction tank, a separation membrane is arranged on the upper end face of the filter plate, and return pipes are fixedly mounted at the top and the bottom of the extraction tank in a penetrating manner. One return pipe is fixedly connected with one extract discharge pipe in a penetrating manner, and one end of the extract discharge pipe is movably connected with a second switch valve. According to the external circulation extraction device, after a mixture enters the extraction tank to be extracted, a medicine extract and medicine residues are separated through the separation membrane, so that the extract and the medicine residues are conveniently separated, the extract flows into the bottom of the extraction tank through the separation membrane and flows out th