| Equipment & manufacturing is the major industry in national economy. Machine tool industry is the base of equipment & manufacturing, and national defense. The profile grinder with multi-axis simultaneous CNC (Computerized Numerical Control) is a kind of advanced machine tools. The grinder has some prominent merits, such as high grinding efficiency, good surface quality, and high profile accuracy. Besides, precision machining for complex curve surface and groove of part which is made of hard alloys being able to endure high temperature can be realized. The grinder has been widely applied in the field in aero-engine, automobile, etc. But some problems have not been solved, for example multi-axis simultaneous CNC, on-line wheel trimming, etc. Moreover, advanced profile grinding equipments with CNC are lacked. It is quite required to make a study of developing a deep cut creep feed MKL7150×16/2 type profile grinder of 7-axis with 5-axis simultaneous CNC.The whole technical design of the profile grinder is proposed. Feed drive system design is focused on. The feed system of wheel head using traditional low waist design results in the bad movement stability and low stiffness. The middle waist design of pole is invented. It is shown that compared with the traditional design, the novel one has better movement stability and higher stiffness. The seal of spindle adopting traditional mechanical maze has some inherent weaknesses. The seal performance of this method is bad. Besides, High pressure and big flux grinding fluids is difficult to be prevented from entering bearings. The novel seal method of using pressurized air is invented. In view of pressurized air flow barrier, sand and dust, and grinding fluid can be prevented from entering bearings.The profile grinding control of vanes of 7-axis with five-axis simultaneous CNC is presented. The CAM technology of 5-axis simultaneous CNC adoped by machining center is not suitable for the profile grinding of vanes. The mathematical model of 7-axis with 5-axis simultaneous CNC is established to be suitable for the profile grinding of vanes. And the corresponding soft is developed by UG. It is indicated that the control of precision profile grinding for vanes of 7-axis with 5-axis simultaneous CNC can be realized by the developed soft. Besides, it is proved that the developed soft can satisfy engineering requirements.In the case of long-term work, thermal stability of domestic profile grinders with CNC is difficult to be guaranteed. The error compensation of hot deformation for profile grinders can be achieved by temperature measurement of key points and temperature control. It is demonstrated that the hot deformation of spindle can be controlled in the range of±0.005mm by making use of this technique. Otherwise, the maximum hot deformation of spindle is reached to 0.146mm.Based on the above research, a deep cut creep feed MKL7150×16/2 type profile grinder of 7-axis with five-axis simultaneous CNC is successfully developed. The developed grinder is used to grind the steering gear, fan-shaped gear arm shaft, and convex and concave circular arc surfaces for aero-engine vanes. It is shown that compared with the traditional machining, the advanced one can improve surface quality, precision and efficiency obviously.The work of this paper provides theoretical basis and an engineering application case for developing a profile grinder with multi-axis simultaneous CNC.
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