Negative pressure percussion bit cover

The utility model relates to a negative pressure percussion bit cover, (1) one terminal surface of its drill sleeve open has drilling rod via hole (3) and drilling rod via hole (3) to open negative pressure air suction opening (2) all around, and drill sleeve (1) other end is opened has back drilling rod via hole (5) and back drilling rod via hole (5) face and drilling rod face seal cooperation, and the drill bit ways is equipped with negative pressure air extraction mouth (4) on one's body. Negative pressure air suction opening (2) are saw tooth structure. Drill sleeve (1) adopts rubber materials preparation and back drilling rod via hole (5) hole face to put sealed the pad. The utility model discloses can reach effectively to advance and retrieve the drilling dust, can not produce secondary pollution again, avoid the production of operative employee's occupational disease, a drill sleeve terminal surface is opened to be had drilling rod via hole and drilling rod via hole to open all around to have the negat