Chuck with anti-loosening function

The utility model relates to the technical field of lathe workpiece machining, and discloses a chuck with an anti-loosening function, which comprises a chuck and an anti-loosening device arranged on the chuck, the anti-loosening device comprises a tensioning rod fixedly connected to the outer wall of the chuck, a lantern ring hinged to the other end of the tensioning rod and a hydraulic telescopic rod fixedly connected to the inner wall of the lantern ring, and the hydraulic telescopic rod is fixedly connected to the inner wall of the lantern ring. The clamping piece is fixedly connected to the other end of the hydraulic telescopic rod. By arranging the anti-loosening device, when the lathe workpiece is clamped by the chuck to work, the lathe workpiece is pulled rightwards, the clamping piece exerts frictional resistance on the lathe workpiece, the lathe workpiece drives the clamping piece to tend to move rightwards, the clamping piece drives the hydraulic telescopic rod to tend to move rightwards, and the hy