usually we say screw compressor that refers to the twin-screw compressor, in the compressor host parallel configuration of a pair of intermeshing spiral rotor, usually outside the pitch circle with a convex tooth rotor (from the cross-section), known as the Yang rotor or Yang screw; pitch circle with a concave tooth rotor (from the cross-section), known as the yin rotor or yin screw. Generally the male rotor acts as the active rotor, and the male rotor drives the female rotor to rotate. The ball bearings on the rotor enable the rotor to achieve axial positioning and withstand the axial force in the compressor. Tapered roller thrust bearings at both ends of the rotor enable the rotor to realize radial positioning, and withstand the radial and axial forces in the compressor. In the compressor host were opened at both ends of a certain shape and size of the orifice, one for suction called suction port; the other for exhaust called exhaust port.
The screw compressor was invented by Professor Lysholm of the Royal Swedish Academy of Technology in 1934. Due to the design, manufacturing level of restrictions, before the sixties screw compressor development is relatively slow; early sixties oil injection technology was introduced into the screw compressor, reducing the screw rotor profile machining accuracy requirements, while the unit's noise, structure, speed, etc. have a favorable impact. At present, the oil-injected screw compressor has become the air power, refrigeration and air-conditioning industry in the main models, in the medium volume flow of air power units and medium refrigeration units, screw compressors in the market has occupied a leading position.TOKA Teco Air Compressor