Double stage permanent magnet variable frequency air compressor

First, the introduction ofDouble stageair compressor
Double stageair compressor referred to as screw air compressor has become the mainstream of air compressor development in today's world, with extremely superior and reliable performance, its small vibration, low noise, high efficiency, few wearing parts, with other types of air compressors (such as piston type) incomparable performance advantages. The precise coordination between the yin and yang rotors and between the rotor and  the main engine shell reduces the backflow leakage and improves the efficiency; Only the rotors mesh with each other, and there is no reciprocating movement of the cylinder, which reduces the source of vibration and noise; The unique lubrication method offers many advantages:
1. With the pressure difference generated by itself, the lubricating oil is continuously injected into the compression chamber and bearing, simplifying the complex mechanical structure.
2. The injected lubricating oil can form an oil film between the rotors, and the main rotor can directly drive the sub-rotor to rotate without the help of high-precision synchronous gears.
3. The injected lubricating oil can increase the air tightness.
4. The lubricating oil absorbs a large amount of compression heat, so even if the compression ratio reaches 16, the machine head can still be controlled below the carbon formation and deterioration temperature of the general lubricating oil, and there will be no friction between the rotor and the casing due to the difference in expansion coefficient.
5. Lubricating oil reduces noise caused by high-frequency compression.
6. A trace amount of oil enters the compressed air, which has a certain lubricating effect on pneumatic tools.

          Second, the structure of the Double stageair compressor body
1. Basic structure
The Double stageair compressor products produced by the company are a kind of twin-shaft volumetric rotary compressor, generally known as twin-screw air compressors. The air intake port is opened at the upper end of the casing, the exhaust port is opened at the lower part, and a pair of high-precision main and auxiliary rotors are mounted horizontally and parallel inside the casing. The main rotor has five shaped teeth, while the  secondary rotor has six shaped teeth; The main rotor diameter is larger and the secondary rotor diameter is smaller. The teeth form a spiral shape that surrounds the outer edge of the rotor, and the two tooth shapes mesh with each other. Both the main and auxiliary rotors are supported by bearings.

2. Transmission mode
The permanent magnet frequency conversion screw air compressor produced by the company has two ways: direct motor transmission and direct coupling transmission.
3. Fuel injection
The motor drives the main rotor to rotate through the transmission mechanism. The cooling lubricating oil is directly sprayed into the inter-rotor meshing part through the nozzle from the lower part of the compressor casing, and mixes with air to take away the heat generated by compression, while forming an oil film, on the one hand, to prevent direct contact between the metal between the rotors, on the other hand, to close  the gap between the rotors and between the rotors and the casing. The injected lubricating oil also reduces the noise generated by high-speed compression. Due to the difference in exhaust pressure, the fuel injection weight is about 5~10 times the weight of the air.

          Third, the working principle of Double stageair compressor
1. Inhalation process:
The screw air compressor has no intake and exhaust valve groups, and the intake is only regulated by the opening and closing of the intake control valve outside the main engine. When the groove space of the main and auxiliary rotors is transferred to the casing intake end wall opening, its space is the largest, at this time the groove space under the rotor communicates with the free air of the air intake, because the air in the tooth groove is fully discharged when the exhaust is finished, the tooth groove is in a vacuum state, and when it is transferred to the air intake, the outside air is sucked in. and flows axially into the tooth groove of the main and auxiliary rotors. When  the air fills the entire tooth groove, the end face of the intake side of the rotor is turned away from the air intake of the casing, and the air between the tooth grooves is closed, which is the"intake process".
 2. Sealing and conveying process:
At the end of suction, the main and auxiliary rotor teeth are sealed with the casing, and the air in the tooth groove no longer flows out, which is the"closing process". The two rotors continue to rotate, their tooth peaks and grooves coincide at the suction end, and the anastomosis surface gradually moves towards the exhaust end, which is the"conveying process".
3. Compression and injection process: During the conveying process, the meshing surface gradually move.