Gas-efficient packaging machine gas efficient replacement structure

A gas-efficient replacement structure for an air-conditioning packaging machine includes an air-exchange module [14] and an upper-mold pressure plate [12] for moving up and down corresponding to the air-exchange mode [14]. The top of the air-exchange mode [14] is a heat-sealing film. On the surface, at least one ventilation chamber is concaved on the film surface, and a positioning box for the packaging box is arranged in the center of each ventilation chamber. The positioning seat of the packaging box is lower than the surface of the heat sealing film, so that the packaging box [17] is exposed and heat-sealed. The membrane surfaces are parallel and separated by a gap. One end of the ventilation chamber is provided with a row of parallel jet holes [21], and the other end is provided with a corresponding row of exhaust holes [23]. The jet holes [21] communicate with the intake passage. The vent hole [23] communicates with the exhaust passage, characterized in that the jet direction of the jet bore [21] passes parallel to the parallel gap between the package opening and the heat sealing film, or at the exit of the jet hole [21] The guide surface [20] is provided, and the jet direction at the end of the guide surface [20] is parallel to the parallel gap between the package opening and the heat seal film. The air flow rapidly flows through the gap at the top of the box and generates negative pressure. The original air in the box is removed and replaced with fresh air.