A vacuum pump is a device that can extract gas from a sealed container to create and maintain a vacuum. It is widely used in scientific research and industrial fields to provide various vacuum environments.

The working principles of vacuum pumps vary, mainly including the following types:

1.Positive displacement vacuum pump: The pump chamber volume changes periodically to complete the suction and exhaust process. This type of pump is divided into two types: reciprocating and rotary vane. Reciprocating vacuum pumps use the reciprocating motion of the piston to inhale, compress and exhaust gas; rotary vane vacuum pumps use the rotating rotor to inhale and compress gas.

2.Dry vacuum pump: does not use oil or other liquids as sealing media, suitable for environments that require oil-free clean vacuum, such as semiconductor etching processes, etc.

3.Liquid ring vacuum pump: When the rotor rotates, it throws liquid (such as water or oil) into the pump casing to form concentric rings of liquid, which form several small volumes that change periodically with the rotor blades to achieve suction and compression.

4.Roots vacuum pump: It is equipped with two rotors that rotate synchronously in opposite directions. A certain gap is maintained between the rotors and between the rotors and the inner wall of the pump casing. It is a rotary variable displacement vacuum pump.

5.Momentum transfer pump: Relying on high-speed rotating blades or high-speed jets to transfer momentum to gas molecules, achieving continuous transmission of gas from the pump inlet to the outlet. Molecular vacuum pump is an example of this type of pump.

6.Jet vacuum pump: uses the momentum generated by a high-speed jet to transport gas to the outlet. It can be a liquid jet, gas jet or steam jet vacuum pump.

Vacuum pumps provide the necessary vacuum environment, enabling many industrial processes and scientific experiments to proceed smoothly. They are one of the indispensable equipment in modern industry and scientific research.