There are many ways of filling; there are plunger pump filling, peristaltic pump filling, gravity funnel filling, measuring cup filling, etc., they are filling more or less Of the drip phenomenon - the liquid droplets in the bottle wall or filling machine, and negative pressure filling is a good solution to this problem, a filling is completed, the remaining liquid in the filling head of the vacuum pump Into the negative pressure chamber, and then back through the return pipe to the liquid storage chamber, so as to ensure that the phenomenon does not occur drip.