Anti-backflow drainage tube for endoscopic interventional therapy

The utility model discloses an endoscopic interventional therapy anti-backflow type drainage tube which comprises a negative pressure ball, a liquid outlet tube used for discharging liquid is arranged on one side of the negative pressure ball, a drainage tube used for introducing liquid is arranged on the other side of the negative pressure ball, the drainage tube is connected with the negative pressure ball through a one-way valve, an adjusting assembly is arranged on the outer wall of the drainage tube, and the negative pressure ball is connected with the drainage tube through a one-way valve. By the adoption of the design, the threaded cover is matched with the threaded groove in the surface of the shell, the purpose of reducing looseness of the threaded cover caused by accidental touch can be achieved, the flow limiting block is matched with the rotating rod and the limiting block, the drainage tube can be gradually pressed in the descending process of the threaded cover, medical staff can conveniently ob