Sluice gate capable of rotating alternately to change sliding surface to reduce friction

The invention discloses a sluice gate capable of rotating alternately to change a sliding surface to reduce friction. The sluice gate comprises a gate frame, wherein the top of the gate frame is in threaded connection with a screw. According to the sluice gate capable of rotating alternately to change sliding surfaces to reduce friction, the screw and pulleys are cooperatively used, a gate plate at the initial state is located at the bottom of the gate frame, one sides with the pulleys of movable blocks are on the inner side, when the gate plate needs to be opened, a rotating wheel is rotatedclockwise, the rotating wheel drives the screw to rotate clockwise, the screw drives a bevel gear to rotate, and the movable blocks are rotated clockwise by 180 degrees through a series of transmission, so that one sides with the pulleys rotates to the outside; and the pulleys are tangent to the inner wall of the gate frame, and the screw is rotated clockwise, so that the gate plate can be drivento move upwards. Due to th