Pneumatic liquid quantifying method and device thereof

The invention provides a pneumatic liquid quantifying device. The pneumatic liquid quantifying device is characterized by comprising a container for containing liquid, a closed liquid quantifying cup, an air pump, a liquid inlet valve, and a liquid outlet valve, wherein the air pump is connected with the closed liquid quantifying cup through an air inlet and outlet pipe; the distance between a liquid inlet pipe built in the closed liquid quantifying cup and the bottom of the cup is a quantified; the liquid inlet pipe built in the closed liquid quantifying cup is connected with a pipeline inserted into the liquid in the container through the liquid inlet valve; and the liquid outlet valve is formed on the pipeline connected with the bottom of the closed liquid quantifying cup. A pneumatic liquid quantifying method is used for finishing liquid feeding, quantifying and liquid discharging processes by virtual of power of the air pump under the action of an alternative switch of the liquid inlet valve and the liquid outlet valve; the method is easy to implement; the work is reliable, and easy to regulate and calibrate; because the liquid and air have the washing function to the pipeline in the pneumatic process, the retardation and residue are reduced; and the method is suitable for quantifying corrosive liquid and unclean liquid.