Gear mechanism is used to transfer the motion and power between any two shafts in space. Compared with other mechanical transmission forms, gear transmission has the advantages of large transmission power range, high transmission efficiency, accurate transmission ratio, long service life and good reliability. Gear machining can be divided into two categories: no chip machining and chip machining; From its processing principle, it can be divided into: generating method (i.e. generating method), profiling method and molding method. At present, the processing methods of gears mainly include: gear pulling, gear hobbing, gear shaping, gear shaving, gear grinding, gear honing, gear planing, gear grinding, gear milling, gear punching and injection molding. Various methods of gear machining have their unique advantages and characteristics, but gear hobbing is the most widely used in automobile gear production.
Based on the existing research results of gear processing technology and hob development technology, aiming at the practical problems existing in automobile gear hobbing processing of user enterprises, the following aspects are studied:
- Based on the hobbing mechanism, the hobbing cutting motion model is established. Through the research on the process of tooth slot cutting and tooth profile formation and the stress analysis of hob, the research foundation of automobile gear hobbing cutting process is established;
- Through the analysis of gear machining error and the research on the formation mechanism of tooth profile error, the influence law of hob and process system on gear hobbing error is obtained, and the control measures of gear hobbing error are put forward;
- According to the processing characteristics of automobile gear products, the design parameters of hob are studied, and the calculation method of hob design parameters is put forward, which is applied to the design of high-efficiency and high-precision hob;
- Based on the actual gear processing of enterprises, study the gear hobbing process parameters, put forward the calculation method of hob installation and positioning, and complete the selection of processing parameters of typical automobile gear products.