The principle of an air compressor is to suck in air and compress it using a compressor, increasing its pressure and storing it in a gas container.
The operating principle of an air compressor is based on different compression technologies, and it can be divided into various types according to different classification criteria. Common types include reciprocating (piston-type) air compressors, screw-type air compressors, and centrifugal air compressors. The working principles of these three common types of air compressors are as follows:
1. Reciprocating (Piston-Type) Air Compressor: The electric motor drives the compressor crankshaft to rotate through a coupling. When the piston moves from the top dead center to the bottom dead center, the suction valve opens, and external air enters the cylinder through a filter. When the piston moves back from the bottom dead center to the top dead center, the suction valve closes, and the gas in the cylinder is compressed as the volume of the cylinder decreases, with its pressure gradually increasing. When the pressure inside the cylinder rises above the gas pressure outside the discharge valve, the discharge valve opens, and the compressed air enters the air receiver through the pipeline.
2. Screw-Type Air Compressor: When a pair of intermeshing male and female rotors (or called screws) rotate inside the cylinder, the space between the rotor tooth grooves expands, and external air is sucked in. As the screws continue to rotate, the air is gradually compressed and moves from the suction side to the discharge side along the rotor axis. When the air is compressed to a certain pressure, it is discharged to the air receiver through the outlet.
3. Centrifugal Air Compressor: A centrifugal air compressor accelerates air through a rotating impeller, and then further increases the pressure through a diffuser and a volute. Air enters the compressor through the air inlet, is accelerated by the impeller, and thrown outward. The impeller rotates continuously, and gas is continuously sucked in and thrown out, thereby maintaining the continuous flow of gas.