The research of bevel gear in China started relatively late. Since the 1970s, the gear machine tool of Gleason Company of the United States has been introduced, and the calculation formula of Gleason Company has been deduced and improved. The former Ministry of Machinery Industry of China listed “Gleason complete set of Technology Research” as a key scientific research project, and organized many colleges and universities and scientific research institutions to tackle key problems. After the “Seventh five-year Plan” and “eighth five-year Plan”, we basically found out the theoretical basis and processing principle of Gleason gear, imitated the 525 and 528 gear milling machines designed by Kellinsky and others in the Soviet Union, and then produced Y2140, Y225, Y228 spiral bevel gear machine tools. The transmission system of this kind of machine tool is complex, which mainly transmits motion through the meshing between gears, and the transmission chain is long. Once there is an error, it will affect the whole transmission chain and cause the manufacturing error of bevel gear. The transmission system of this kind of gear milling machine consists of five movements: (1) cutter head rotation motion, (2) feed motion, (3) hobbing motion, (4) indexing motion, (5) shaking table swing, these five movements influence each other. Before machining gears, the machine tool must be adjusted, and the adjustment is complex, and sometimes it has to be adjusted repeatedly. Therefore, the processing time is long and the production cycle is long. This seriously affects the quality and machining efficiency of bevel gears. Due to the great advantages of NC technology, during the eighth five-year Plan period, Tianjin No.1 Machine tool Factory developed NC gear milling machine, but it could not be fully numerically controlled, and the machine tool mechanism was complex because of the use of shaking table drum and knife tilting mechanism.
At present, there are mainly the following research units in spiral bevel gear theory: state key Laboratory of Mechanical Transmission of Chongqing University, Xi’an Jiaotong University, Central South University, Huazhong University of Science and Technology. They are mainly engaged in gear design, tooth surface contact analysis, tooth surface loading analysis, tooth surface machining principle and other aspects of research, and achieved certain results, but there is still some gap with the practical application. Recently, they have developed all kinds of gear milling machines after digestion and absorption. Qinchuan Machine tool Group and Xi’an Jiaotong University jointly developed the YK2240 numerical control spiral bevel gear milling machine, and Changsha Railway Institute developed the YK2245 gear milling machine. However, the numerical control systems they use are mainly imported, and the derivation of numerical control theory is still based on the original Gleason machine tool model, which can not get rid of the shaking table, tool rotation and tool tilting mechanism of Gleason machine tools, and the derivation process is complex.