Ultrasonic edge pressing device for freshness protection bag

The utility model discloses an ultrasonic edge pressing device for a freshness protection bag. The freshness protection bag comprises an upper layer of film, a lower layer of film, folio parts and sealing parts, wherein each folio part and each sealing part are located on the two sides of the corresponding film. The ultrasonic edge pressing device is characterized by comprising a machine table, a freshness protection bag conveying mechanism, a pressing rod and an ultrasonic generator, wherein the freshness protection bag conveying mechanism is connected to the machine table, and the pressing rod is used for abutting against the folio parts, and the ultrasonic generator is used for heating the folio parts so that the thickness of the folio parts can become smaller. The pressing rod and the ultrasonic generator are both connected to the machine table and arranged in the vertical direction in the manner of being partitioned by the folio parts. The pressing rod abuts against the upper end faces of the folio parts, the ultrasonic generator emit ultrasonic waves to be aligned with the lower end faces of the folio parts, in this way, the folio parts are flattened under the action of the pressing rod and under the heating action of the ultrasonic waves, and redundant air in the folio parts is also discharged under the extrusion action of the pressing rod; accordingly, it can be guaranteed that the folio parts are absolutely flat, so that the thickness of the freshness protection bag is uniform when the freshness protection bag is wound around a shaft sleeve, and the freshness protection bag is more attractive in appearance.