Pre-stretching device for film wrapping machine

The utility model provides a technical scheme of a pre-stretching device for a film winding packaging machine. The program mainly includes a bracket and a speed-regulating motor fixed on the top of the bracket, and an axis-parallel feeding roller and a film-loading shaft installed on the bracket. The output shaft of the speed-adjusting motor is driven to convey the rubber roller through a transmission belt, and a shaft is mounted on the bracket. Corresponding side there is a film axis, this program is in the transfer roller and the film axis there is an axis and the transfer roller parallel to the axis of the stretch roller, the stretch roller on the coaxial Stretching the rubber roller pulley, the stretching rubber roller pulley is connected with the conveying roller roller coaxially through the stretching belt and the feeding roller; there is a spring at the corresponding end of the film mounting shaft of the bracket, and one end of the spring is fixed on the bracket. The other end is fixed with a connecting rod, a tension roller is connected to the lower end of the connecting rod, the upper end is connected with the cam, and the displacement sensor is in contact with the cam.