Research On The Key Technology For The Design And Manufacturing Of Engine Ceramic Rocker Arm

For the sake of solving the problem of great rotary inertia and forged steel rockerarm's bad wear-resisting property in the engine of Xia Li cars with modelTJ370Q TJ376Q, we utilize the assembly theory of creative engineeringmethodology to respectively make the aluminum alloy materials and siliconnitride engineering ceramics as base stock of rocker arm and cabochon glut. Inthis way, the goodness of these two kinds of materials are fully strengthened. Forthe new rocker arms, their comprehensive property are enhanced and the cost ofmanufacture is lower than before.Aimed at producing rocker arms on a large scale, this paper mainly deals with theresearch of key manufacture technology in the process of production. All of the contentcan be summarized as below:1. This paper discussed property requirement of rocker arms, engineering ceramics'mechanic property and their application in engine's admission gear, machiningmechanism and techniques of ceramic material and quality control method. Based onall of above discussion, the main content and significance of this paper areproposed.2. In view of existing problem of research on rocker arms, we propose the keytechnique in our research that the techniques of connecting the base stock ofrocker arms with cabochon gluts, the techniques of gluts preparation andmachining and the techniques of machining the aluminum base stock. At thesame time,the research report is worked out with the aim of mass-production.3.To test the probability that the ceramics gluts are broken because of thermalstress during the process of compression casting, the temperature field and thethermal stress field are verified with the method of finite element analysis. Thenthe rocker arms with ceramic gluts are compared with shank type rocker arms.4. To lower the cost of machining, a new process technique is proposed, namely,the ceramic gluts are ground by plain aluminum grinding wheels after theircoarse grinding with diamond grinding wheels. Many factors which could beimpair the quality of ceramics surface such as grinding quantity, material'smechanic property and cooling liquid are analyzed. In this way, the bestprocessing techniques of grinding is determined.5. By testing grinding force, analyzing X-ray diffraction and energy spectrum,and measuring the surface roughness cures, we propose the grinding mechanismand build the grinding models of the grinding process with plain aluminumgrinding wheels.6. The preparation process techniques of ceramics including the techniques ofbody formation and sintering, pressure casting of aluminum alloy and theprecision machining of the rocker arms' axle holes are analyzed with themethod of quality control to guarantee the quality of production.7. After 720 hours simulating bench test, 300 hours bench test with maximumspeed and maximum load and 50 thousand kilometers running experiments, weconcluded that the TJ370Q engines with ceramic rocker arms are better thanthose with forged steel rocker arms in wear-resisting property, dependability,dynamic property, speed characteristics, initial power property, economicalefficiency, emission level, and noise intensity.Finally, research findings are summarized and the further research presumptionsare proposed.