Replacing piston compressors with screw compressors is an inevitable trend in the development of power air compressors. Screw compressors are divided into twin screw and single screw. The pair of rotors of the twin-screw compressor is essentially a pair of helical gears, which belong to the plane meshing. The tooth shape of the twin-screw compressor is mainly imported, and the numerically controlled grinding machine for rotor finishing is completely dependent on imports. Due to the gap between the performance of domestic twin-screw air compressors and foreign countries, imported twin-screw compressors occupy a dominant position in the domestic market, not only expensive, but also maintenance and spare parts supply. This situation will be on the national economy. The safety has an adverse effect. Screw compressors are widely used in the fields of the National Defense Forces, air and refrigeration. For example, the navy has strict requirements on the technical performance of air compressors: submarines must use high-pressure air to discharge water before they can surface, while submarine noise is easy to be captured by enemy sonar. Therefore, the compressor is required to have low vibration and low noise. Good reliability and energy saving. The US Navy has rigorously demonstrated the various types of air compressors, and believes that the single-screw compressors can fully meet the requirements of submarines for high-performance compressors because of the above advantages. However, the single-screw compressor rotor is a space meshing pair. The research of meshing theory and the development of processing technology are more difficult than the twin-screw compressor. At present, only a few countries such as Japan and the United States can produce after the introduction of French patents, mainly for air. Compressors, air conditioning compressors and process compressors. The single-screw compressor is the only high-grade compressor that has not been introduced in China. Since the 1970s, China has been working on the development of single-screw compressors. The research and development work has been supported by the former State Science and Technology Commission, the National Defense Science and Technology Commission, relevant departments and provinces, and has made some progress, but has not yet solved the high-precision special machine tools. With the key technologies such as star wheel processing, the development of single-screw compressors requires further improvement in terms of life and energy consumption. In the single-screw compressor, the meshing pair consisting of a screw (worm) with 6 slots and a star wheel (worm gear) with 11 teeth is essentially a pair of special high-precision toroidal worm pairs. Its special feature is that the shape of the screw is not a torus but a cylindrical surface (or the shape of the screw is the same as that of a normal cylindrical worm, and its tooth shape is the same as that of the toroidal worm). This new tooth profile of the star wheel is very advantageous in terms of improving the sealing performance and working life of the meshing pair, but its processing technology must also be solved. The following problems can be encountered when machining this new tooth profile with a conventionally designed hob: 1 The positive rake angle of the hob blade should vary by nearly 30° from head to tail, but in deep and narrow sipe, sharpening Such a rake face is difficult to achieve; 2 the tooth shape and tooth width of the star wheel processed by the hob re-grinding will be unacceptable; 3 the accuracy of the shovel process is difficult to guarantee. In order to solve the problem of machining the new tooth shape of the single-screw compressor star wheel, the author developed a special hob. The solid cutting test was carried out with the designed short hob. The results show that the rolling process is smooth and smooth, and the meshing clearance of the processed star wheel meets the design requirements. The contact surface of the tooth surface is evenly distributed, and the contact area is more than 90%. The measured displacement is more than 1% higher than the international advanced level. On this basis, the tooth width of the star wheel was changed from the original left and right half teeth to the unequal tooth width, and the “energy-saving and long-life single-screw compressor†was invented. The energy-saving long-life single-screw compressor has a lower energy consumption of 0.5kw/m 3 ·min -1 and a volumetric efficiency of 5% or more compared with the international advanced level through the application of this special hob. The life of the star wheel has increased by more than 10%. Its industrialization has been supported by the SME Technology Innovation Fund of the Ministry of Science and Technology. The performance and technical level of the products have been highly appreciated by many academicians of the Ministry of Science and Technology and welcomed by users. At present, the product has been serialized and invested in bulk cattle production, and the product can save hundreds of millions of degrees per year. Compared with the star-shaped machining process in which the screw grinding wheel is used in the foreign countries, the star rolling process has the advantages of high efficiency and low cost. At present, Zhengli Precision Machinery is the only enterprise in China that masters this special hob design and manufacturing technology, and is making new efforts to further expand China's basic research, process technology and process equipment in single screw compressors. . Komatsu Cab Parts,Komatsu Cab Door Parts,Komatsu Cab Genuine Part,Komatsu Excavator Cab Parts JINING SHANTE SONGZHENG CONSTRUCTION MACHINERY CO.LTD , https://www.sdkomatsugenuineparts.com 1 Introduction
2 star wheel tooth profile
w 1 - star angular velocity; w 2 - screw angular velocity;
1. Star wheel 2. Screw 3. Bus bar 4. Secondary envelope surface 5. Second working area
figure 1 3 star wheel hob design
4 practical effects
5 Conclusion