Sand cylinder change-over valve

The utility model relates to a sand cylinder change-over valve which comprises a valve body, a movable valve plate, a fixed valve plate, a shifting fork and a driving device controlling the valve plate to rotate, the fixed valve plate is fixed in the valve body, the movable valve plate driven by the driving device is matched with the fixed valve plate in a rotating and sealing mode, and the sand cylinder change-over valve is provided with a water inlet, a water outlet, a water outlet, a filter element upper connector and a filter element lower connector. Four through holes and a blind hole are formed in the gyration radius of the outer part of the fixed valve plate, and the first to fifth holes are arranged in sequence and are adjacent in pairs; and the movable valve plate is provided with a water inlet through hole which is normally communicated with the water inlet on the valve body, and is also provided with an arc-shaped conducting blind hole. According to the sand cylinder change-over valve, all function