One minute understanding of positive pressure roots blower and negative pressure roots blower!

These two concepts should start with normal pressure.

Atmospheric pressure refers to an atmospheric pressure, that is, the gas pressure generated by the atmosphere we usually live in. A standard atmospheric pressure is 101325 Pa. 100000Pa=100KPa, so "one standard atmospheric pressure" is also commonly expressed as 100KPa or 101KPa. Due to different geographical location, altitude, temperature and other factors, the local actual atmospheric pressure is not always equal to the standard atmospheric pressure, but for the purpose of simplification, sometimes it can be approximated that the atmospheric pressure is a standard atmospheric pressure, namely 100KPa,

Positive pressure, in short, refers to the gas state with higher pressure than normal pressure. For example, the positive pressure is generated at the outlet end of the pump or pump when the blower is used to supply air, or when the bicycle or car tire is inflated.

Negative pressure refers to the gas state lower than the atmospheric pressure, which is also known as "vacuum". For example, the working environment of vacuum pump belongs to negative pressure; When drinking from a tube, there is negative pressure in the tube; The suction cup used to hang things is also negative pressure.

Therefore, the positive pressure fan can be generally understood as the blower equipment for air blowing, while the negative pressure fan is the blower equipment for suction.