An air compressor is a device used to compress gas. The air compressor is similar in construction to the water pump. Most air compressors are reciprocating piston, rotary vane or rotary screw. Centrifugal compressors are very large applications.

The compressor is directly driven by the electric motor to make the crankshaft rotate, and the connecting rod is driven to make the piston reciprocate, causing the cylinder volume to change. Due to the change of the pressure in the cylinder, the air enters the cylinder through the air filter (muffler) through the intake valve. During the compression stroke, due to the reduction of the cylinder volume, the compressed air passes through the exhaust valve and passes through the exhaust pipe. The direction valve (check valve) enters the air storage tank, and when the exhaust pressure reaches the rated pressure of 0.7MPa, it is controlled by the pressure switch and automatically stops. When the pressure of the air storage tank drops to 0.5--0.6MPa, the pressure switch will automatically connect and start [2] . The air compressor is the core equipment of the pneumatic system and the main body of the electromechanical bleed air source device. It is a device that converts the mechanical energy of the prime mover (usually an electric motor or a diesel engine) into gas pressure energy.