Tail tensioning device of belt conveyor

The utility model belongs to the technical field of belt conveyors, and particularly relates to a belt conveyor tail tensioning device which comprises a tail support, a tail roller and a conveying belt, the left end and the right end of the tail roller are connected with sliding seats through roller shafts and bearing seats, the sliding seats are connected with the tail support in a sliding mode, and inner threaded sleeves are arranged at the rear ends of the two sliding seats. Worm and gear elevators are installed on the left side and the right side of the rear end of the tail support respectively, threaded rods of the worm and gear elevators are in threaded connection with the inner threaded sleeves in a matched mode, deviation correcting sensors for detecting deviation of the conveying belt are arranged on the outer sides of the left edge and the right edge of the conveying belt respectively, and a tensioning sensor for detecting drooping of the conveying belt is installed below the front portion of the ta