Automatic compensation ventilation piston cylinder type blanknig apparatus

The utility model relates to an automatic feeder of a compensation and ventilation piston cylinder type, which belongs to the field of a special feeding device for an aluminum electrolysis device in a non-ferrous metal industry. A control cylinder (1) is arranged on a flange plate (3) at the upper end of a feeding barrel (5), the middle part of the feeding barrel (5) is provided with four square feeding holes (8), and two ventilation pistons (4) and a pressing block (9) are arranged on a connecting rod (3) and are pressed by the other connecting rod (10). The ventilation pistons are arranged at the inner part of the feeding barrel (5), an opening and closing cone (6) is fixed at the lower end of the connecting rod (10) through nuts, the working surface of the opening and closing cone (6) is a spherical surface, and the ventilation pistons (4) is formed by buckling a steel wire (12), two pressing plates (13) and a steel jacket (14), wherein, the steel wire is folded with three-dimensional stereo wave curves. The utility model can be used widely for various electrolytic tanks of the aluminum electrolysis device.