Pneumatic shearing mechanism for packaging bag

The utility model relates to the technical field of packaging bags, and discloses a pneumatic shearing mechanism for packaging bags, which comprises a base, a plurality of support columns and a support frame, the support columns are mounted on two sides above the base, and the support frame is mounted above the support columns. A rotating device is arranged between the multiple supporting columns and comprises a plate body, first connecting columns and first bearings, the plate body is arranged between the multiple supporting columns, the first connecting columns are installed on the two sides of the plate body, and the two sides of the upper first connecting column are connected with the inner wall of the supporting frame; the two sides of the lower first connecting column are connected with the inner wall of the base, a first bearing is installed on the left side of the outer wall of the lower first connecting column, a connecting ring is installed on the outer wall of the first bearing, and a plurality of