Backflow prevention device of rotary evaporator

The utility model relates to an anti-backflow device of a rotary evaporator, which comprises an anti-backflow communicating pipe and a backflow liquid phase collecting cover, and the anti-backflow communicating pipe comprises a split-phase pipe positioned in the center and joints integrally formed at two ends of the split-phase pipe; a gas phase channel is formed in the center of the split-phase pipe, the pipe wall of the split-phase pipe annularly protrudes outwards to form a plurality of liquid phase drainage grooves, and a plurality of liquid leakage holes are evenly distributed in each liquid phase drainage groove; the backflow liquid phase collecting cover comprises two cover shells, arc-shaped shell edges are arranged at the two ends of each cover shell, and the outer walls of the two cover shells are sunken inwards to form annular fixing grooves. And an arc-shaped recess is formed at the joint of the split-phase pipe of the backflow prevention communicating pipe and the joint, and the shape of the arc-