Pneumatic swing arm structure

The utility model discloses a pneumatic swing arm structure. The device comprises a set of side stand columns, a top frame, a beating plate adjusting mechanism used for adjusting unfolding and foldingof a beating plate and the beating plate. A swing arm adjusting mechanism and a rotating shaft are arranged in the clapper adjusting mechanism; a pneumatic cylinder and a swing arm are arranged in the swing arm adjusting mechanism; the pneumatic cylinder is fixed to the transverse fixing frame through an air cylinder fixing weight. A cylinder head at the output end of the pneumatic cylinder is connected with the swing arm through an oilless bushing; one end of the swing arm away from the cylinder is connected with the rotating shaft through a connecting bearing; air cylinder fixing bases arearranged above and below the rotating shaft respectively, first air cylinders are arranged at the ends, away from the rotating shaft, of the air cylinder fixing bases, the sides, close to the pattingplate, of the first air cyl