The work aims to analyze the movement characteristics and rules of the transverse sealing rotation shaft of pillow packer, and put forward an electronic cam system based on PLC, servo amplifier and servo motor, which is used to replace the existing cam mechanical structure. The mechanical structure and motion track of the transverse sealing shaft of the pillow packer were studied, and the motion model was established in the physical modeling method. The motion process, the model establishment and solution to key parameters of the electronic cam were emphatically discussed. Compared with the traditional high order sub mathematical model, the model was simple and easy to program. Meanwhile, it improved the controllability of the speed at different time points in the course of motion of the transverse sealing rotation shaft, and realized the flexible variable speed rotation. The model solves the problems of worsened cutting effect and packaging accuracy due to the loss of accuracy caused by the long-term wear of the mechanical cam. Thus, the packaging accuracy is improved, the service life of the transverse sealing cutter is increased, and the mechanical vibration of the equipment is reduced.