Automatic door opening and closing air cylinder of high-precision machine tool

The utility model discloses an automatic door opening and closing air cylinder of a high-precision machine tool, relates to the technical field of machine tools, and aims to solve the problems that in the prior art, dust and corrosive liquid are adhered to the surface of a piston rod of an existing air cylinder for automatically opening and closing a door, so that a sealing element of the air cylinder is easily corroded or deteriorated; and the service life of the air cylinder is influenced. A front end cover is installed on one side of the cylinder barrel, the cylinder barrel is fixedly connected with the front end cover, an outer protruding ring is installed on one side of the front end cover, the front end cover and the outer protruding ring are of an integrated structure, a cleaning ring is installed on one side of the outer protruding ring, the outer protruding ring is connected with the cleaning ring in a welded mode, and a containing groove is formed in the cleaning ring. A cotton cushion is arranged i