The key of packaging and packing was the regular arrangement of the pincushion bag. According to to analysis of the physical characteristics and the craft characteristics of the regular arrangement of the pincushion bag, the scalability finishing bag mechanism was designed, The composition and principle of several main mechanisms was analysed comprehensively, such as the key conveyor belt, belt rectification, scalability orientation, scalability driving, etc. According to analysis of the linear velocity of the conveyor belt and the driving conveyor belt scalability when working, the related parameters of the linear velocity of the scalability conveyor belt and the driving conveyor belt scalability was calculated.