Variable-pitch drum screen separator

The utility model relates to the technical field of shot separation equipment, and discloses a variable-pitch drum screen separator which comprises a conveyor, a feeding port is formed in the upper end of the conveyor, a screen box is arranged at one end of the conveyor, a spiral blade is rotationally installed in the conveyor, a driving device is installed at one end of the conveyor, and the driving device can drive the spiral blade to rotationally convey shots. A roller screen is arranged in the screen box, meshes are formed in the outer side of the roller screen and become larger along the material advancing direction, supporting frames are connected to the two sides of the lower end of the roller screen, a cleaning device is arranged at the lower end of the roller screen, the upper end of the cleaning device makes contact with the surface of the roller screen, and a discharging port is formed in the position, perpendicular to the roller screen, of the lower end of the screen box. The cleaning device is ar