Automatic protein liquid spraying device of surface treatment production line

The invention relates to an automatic protein liquid spraying device of a surface treatment production line. The surface treatment production line comprises a travelling crane carrying a workpiece, a rack, a groove body and the automatic protein liquid spraying device, wherein the groove body is connected with the rack through a pivot, under the action of a telescopic cylinder, the groove body is switched between a horizontal state and a vertical state, and when the groove body is in the vertical state, the travelling crane puts the workpiece into the groove body; and the automatic protein liquid spraying device is arranged above the tank body, when the tank body is in a horizontal state, the automatic protein liquid spraying device sprays protein liquid to the workpiece, the automatic protein liquid spraying device comprises a spraying assembly, a guiding assembly and a driving assembly, the spraying assembly is fixed to the guiding assembly, the guiding assembly and the driving assembly are fixed to the rac