Medical gas middle-low flow measuring and changing device

The utility model relates to a medical gas middle-low flow measuring and changing device. A gas path assembly, a differential pressure transducer and an amplifier assembly are arranged in an outer shell box body of the measuring and changing device, a digital panel meter is arranged on a cover plate of an outer shell, wherein, the gas path assembly comprises two tees and spiral gas pipes connected with the tees, and the middle interfaces of the two tees are connected with the differential pressure transducer. The transducer can be used for measuring pressure difference between a spiral inlet and a gas outlet, and the transducer is connected with a circuit of the amplifier assembly. Gas flow rate represented by the pressure difference can be converted to real-time flow rate and cumulative flow rate signals and displayed on the digital panel meter.