Rotary plate tightening and front jacking type locking structure

The utility model relates to the field of miter saw turntable locking structures, in particular to a turntable tightening and front jacking type locking structure, which comprises a turntable, a friction plate and a base, the turntable is connected with the base through a locknut and a hexagon screw, the rear end of the turntable is rotatably connected with a handle, the lower end of the handle is rotatably connected with a screw rod, and the left end of the screw rod is rotatably connected with a pull rod. The left end of the pull rod is connected with a cam, the cam is connected with a locking seat through a pin, the locking seat is fixed to the rotating disc through a first screw, a square groove is formed in the locking seat, an ejector rod is arranged in the square groove in a sliding mode, the right end of the ejector rod is connected with a first nut, and the ejector rod is sleeved with a pressure spring located in the square groove. The end, extending out of the square groove, of the left side of the