The compressor is simply a mechanical unit that elevates the pressure of a gas by increasing the its volume reduction or speed. Compressors are divided into two main groups according to the gas pressure increasing method: positive displacement compressors and dynamic compressors. Compressor types and subcategories are shown in Fig. 1.
In positive displacement compressors, the volume of the tank is mechanically reduced after the intake of the specified amount by means of the intake regulator into the air compression chamber, and the pressure of the air is increased by this reduction rate until the desired pressure is reached. Such compressors are divided into two groups according to the type of mechanism used to reduce the volume: Compressors with rotary mechanism and with linear mechanism.