Thermal deformation automatic compensation mechanism for screw rod and machine tool

The invention provides a thermal deformation automatic compensation mechanism for a screw rod and a machine tool. The thermal deformation automatic compensation mechanism for the screw rod comprises a fixed mounting seat, a bearing, a first axial limiting part, a ferrule and an elastic clamping part, wherein the fixed mounting seat is mounted on a fixed pivot; an annular chamber is formed between the fixed mounting seat and the screw rod; the bearing is mounted in the annular chamber and is sleeved on the screw rod; the first axial limiting part is mounted on the screw rod and is arranged close to the first end of the bearing; the first axial limiting part is in supported press contact with an inner ring of the bearing; the ferrule is sleeved in the annular chamber and is arranged close to the second end of the bearing; the ferrule is fixedly connected with an outer ring of the bearing; a pressure chamber is arranged in the fixed mounting seat and is connected with a pressure oil source through an oil path; a