The edge material winding drum is arranged on the frame of the paper bag machine, the screw mechanism arranged side by side with the edge material winding drum, and the motor that drives the edge material winding drum and the screw mechanism to rotate; the swing frame arranged on the frame and Proximity switch set corresponding to the end of the swing frame; fixed on the side of the moving sleeve of the screw mechanism, and used to control the winding speed of the edge material, and the speed control rod that drives the swing frame to swing with the pull of the edge material; connection The other side of the moving sleeve is connected to the swing side of the swing frame, and is hinged to both, and the return spring that connects the swing frame and the frame, and pulls the swing frame to drop, and is connected to the proximity switch and follows the swing frame The controller that controls the start and stop of the motor.