Gear is the key basic part of automobile. Most speed change and transmission components in automobile are related to gear parts. The quality of gear parts directly affects the noise, stability and service life of the whole vehicle. At present, the manufacturing process of automobile gears at home and abroad is still based on cutting, and the typical processing methods are gear hobbing, gear shaping, gear shaving and gear grinding. Among them, gear hobbing technology undertakes the processing of most automobile gears. It can be seen that hob plays an important role in the manufacturing process of automobile gear parts. Hob is a complex tool. The quality and performance of products are directly related to the design principle and manufacturing process of machining tools. So, what should be the basis (starting point) for tool design? Is it the tool design principle or the actual state of the production line? Practice has proved that using appropriate and reliable cutting tools and selecting correct cutting parameters in the field can greatly improve the production efficiency, stabilize the product quality and reduce the manufacturing cost. ZHY casting believes that the main technical bottlenecks in the development of China’s automobile industry are: first, the R & D of core parts (engine and gearbox) is controlled by others, lacking intellectual property rights and design capabilities; Second, the basic technology is backward, and the key is how to convert the basic theoretical research into practical production.
In China, most of the investment in the automobile industry is used to buy manufacturing equipment, while few manufacturers buy the cutting tools used in imported equipment from abroad. Is it that the level of cutting tools in China is basically equal to that in foreign countries? The answer is No. The level of design theory and manufacturing technology of foreign tool manufacturers in the same industry is much higher than that in China. However, more importantly, their design theories are based on the actual needs of the production site.
In actual production, cutting tools also play an important role. For example, hobs must first ensure that qualified parts can be processed; Secondly, it must match the equipment level, otherwise it will seriously affect the processing efficiency and cost; If the equipment has high power, good rigidity and poor tool design or quality factors, the equipment cannot give full play to its advantages of high efficiency; On the contrary, if the equipment has a long service life, but uses very high-quality and efficient tools, it will be a huge waste of tools, and even seriously damage the tools.
Main development trends of automobile gear cutting tools: 1. High speed machining. Improving production efficiency can not only improve the utilization rate of equipment, but also reduce the comprehensive production cost. 2. Use of tools for compound machining. Concentrating the processes such as chamfering into the gear hobbing can improve the machining efficiency and reduce the deviation caused by repeated clamping. 3. Non standardization of complex tools. In order to improve product performance, many engineers do not use standard tool parameters when designing parts, so tool design and manufacturers must adapt to this as soon as possible. 4. Development of materials and coating technology. Tool coating can greatly improve tool life and part surface roughness. 5. The tool accuracy level is improved. With the progress of tool manufacturing technology, the parts that must be processed with fine hob can be realized only with semi fine hob.
Therefore, as a manufacturing enterprise, in order to improve its competitiveness in the market, it must improve product quality and reduce costs. It must focus on the design and use of cutting tools. In this research process, combined with the actual problems in the company’s production line, the topic of “design and Application Research of automobile gear hob” is selected as the research content of the graduation thesis. Through the research, the cutting tool design theory actually needed by domestic automobile manufacturing enterprises is explained and discussed. The research results play an important role in improving production efficiency and reducing the comprehensive cost of parts, and have good economic significance and social benefits.