After the founding of new China, especially since the reform and opening up, gear transmission technology has developed greatly. The application of some new technologies and the penetration of interdisciplinary disciplines have promoted the development of gear design technology and manufacturing technology. Among them, the more prominent are the meshing principle, the design technology represented by CAD and the surface engineering technology represented by tribology And the process technology represented by precision forming. The research and application of these new technologies have raised China’s gear technology to a new level. In addition, a variety of transmission forms have been developed, harmonic transmission is becoming more and more mature, and several new types of gear transmission have come out one after another, such as step involute cylindrical gear transmission, R-V transmission, point line meshing involute gear transmission, special tooth pump and so on. However, involute hard tooth surface gear transmission, circular arc gear transmission, worm gear transmission and bevel gear transmission play a leading role in industry.
1. Hard tooth involute gear
Involute gear transmission is the most widely used form of gear transmission in the world. From the 1960s to 1970s, China mostly adopted hobbing technology for involute gears. The gears produced by this method have low hardness, low contact strength and short service life. By the 1980s, the former Ministry of machinery industry had done a lot of work on the research and development of hard tooth surface technology. The Institute and the factory combined the introduction and digestion of this technology, mastered the hard tooth surface grinding technology of gears, and achieved gratifying results. At present, China can produce high-speed gear boxes with a line speed of more than 125m / s, which solves the urgent need of major equipment in large chemical fertilizer and other industries.
2. Circular arc gear drive
Circular arc gear has been introduced into China from abroad for more than 40 years. Due to its good meshing lubrication performance, convenient and simple processing, it has been developed in China. From single circular arc tooth profile to double circular arc tooth profile, from soft tooth surface to hard tooth surface, Chinese engineers have created circular arc gear technology with Chinese characteristics. Today, high-speed circular arc gears account for 80% of China’s high-speed gears, with a pitch speed of 120m / s, a load factor of 2MPa and a transmission power of 9000kw. For double circular arc gears with low speed and heavy load, the transmission power can reach 5000kW, and the maximum modulus is equal to 30mm.
3. Worm and bevel gear drive
In the 1970s, the research of worm drive has been deeply developed in China. Then the double enveloping hourglass worm drive has reached the international advanced level and has been applied in the screwdown device of large metallurgical rolling mill. Since the 1970s, China has introduced and digested Gleason gear cutting technology and machining machine tools from the United States. In the 1990s, Oricon and Klingenberg tooth cutting technology were also studied. At the end of the 20th century, Qinchuan machine tool factory and Changsha Railway Institute successfully developed CNC spiral bevel gear cutting machine.