Prop a bag arm

The utility model belongs to the technical field of irritate a packet equipment, specifically disclose a prop a bag arm, including the frame with fix the support in the frame, be connected with cantilever crane on the support, be equipped with a pair of string of bag arm on the cantilever crane, hang to be equipped with between the bag arms for two and prop bag cylinder and connecting rod, two bottoms that hang the bag arms are equipped with and hang the bag ring, it has the rotation connecting rod through the round pin hub connection to prop up cantilever crane one end, rotates the connecting rod other end and has connected gradually long stroke cylinder and short stroke cylinder, and the short stroke cylinder is established in the frame. The utility model discloses high just work efficiency is high for simple structure, performance accuracy.