Gravity method protein purification automatic speed control sample loader

The invention relates to the technical field of protein purification, in particular to an automatic speed control sample loader for gravity method protein purification. Comprising a protein liquid containing box designed in an opening mode, a communicating pipe installed at the bottom of the protein liquid containing box, a water level gauge installed on the side, close to the communicating pipe, of the protein liquid containing box, a discharge valve installed outside the communicating pipe and a driving mechanism used for driving the discharge valve to be opened. The water level gauge comprises a water level gauge shell, the speed-controlled sample loading of crude protein liquid can be realized, and the sample loading speed can be automatically controlled according to the liquid level of the protein liquid; meanwhile, an initial point can be adjusted according to the liquid level height of the protein liquid, so that the sample loading speed of the protein liquid is controlled at different liquid levels, a