Automatic sand pumping machine for cable trench

The utility model discloses an automatic sand pumping machine for a cable trench. The automatic sand pumping machine comprises a trailer, a loading and unloading lifting driving device, a loading and unloading vehicle frame, a sand pumping box, a sand pumping fan and a sand pumping pipe, the loading and unloading lifting driving device is arranged on the trailer frame; the loading and unloading vehicle frame is arranged above the trailer frame, one end of the loading and unloading vehicle frame is hinged to one end of the trailer frame, and the loading and unloading vehicle frame is connected with a push rod in the loading and unloading lifting driving device; the sand pumping box is arranged on the loading and unloading vehicle frame and comprises a sand pumping box body and a rear cover plate, the sand pumping box body is provided with a sand unloading opening, a sand inlet and a fan connecting opening, and the rear cover plate is arranged at the sand unloading opening and used for opening/closing the sand