Roller open type water cooling device

The utility model relates to a roller open type water cooling device which comprises a roller. An opening communicated with the inner cavity of the roller is formed in one side of the rotary joint; the housing is rotationally and hermetically connected with the rotary joint, a water inlet is formed in one side of the housing, and a water outlet is formed in the bottom of the housing; the spraying pipe is inserted into the roller from the water inlet and is positioned in the roller, and spraying holes for spraying upwards are formed in the spraying pipe; a backwater gap is formed by a gap between the spraying pipe and the opening; the circulating system is connected with the end part of the tourmaline spraying pipe and the water outlet; water enters one end of the spraying pipe and is sprayed upwards to the inner wall of the roller through the spraying holes in the spraying pipe, the sprayed water is retained in the roller, when the water level of cooling water exceeds half of the height of the roller, the wat