Machine tool spindle unclamping cylinder structure

The utility model discloses a machine tool spindle unclamping cylinder structure which comprises a cylinder barrel and a piston shaft. A flange used for fixing is arranged outside the cylinder barrel, an integrated annular protrusion is arranged on the inner wall of one end of the cylinder barrel, and an oil passing hole A is formed in the side wall of the cylinder barrel; the piston shaft comprises a piston body which is in sliding sealing with the inner wall of the cylinder barrel and a shaft body which is in sliding sealing with the inner wall of the annular bulge, and a through hole is formed in the axis position of the piston shaft; according to the machine tool spindle unclamping cylinder structure, the hollow piston shaft is adopted and combined with the hollow pull claw, the requirement for water outlet in a tool can be rapidly met, the structure is simple, additional parts do not need to be added, and the spindle water leakage problem caused by the assembly problem is solved; and through cooperative