The Finite Element Analysis And Structure Rebuild For The LX150 Motorcycle Crankcase Box Of The Substituted Material

The LX150 Motorcycle Crankcase Box(MCB) is component of the left Crankcase Box and right Crankcase Box, which are the important parts of the Motorcycle. The intensity and stability of crankcase box crucially effect on the function of the whole Motorcycle. With the development of Motorcycle industry towards high speed and lightweight, the selection of material has become hot topic of scholars all over the world. Since most motorcycle technologies of our country are introduced from Japan, the researches on the intensity and stability of MCB in our country are few. At present, the crack is found after the MCB runs a certain time in our country. Then, to enhance the intensity and stability of Crankcase Box through adopting new material and optimizing its structure are the important topics which need solved.Sponsored by National science-technology key program (No.2001BA311A05-4), this paper researches on nonlinear dynamic and static problems of MCB, builds up static model with finite element method, and achieves some fruits. The main contents of the thesis are as followed:1. The paper introduced the modeling methodology, basic theory of finite element, the selection of analyzing software, the method of decided material property, the method of obtained parameters of exterior load and the load of Crankcase Box's bearing hole, indicated how to deal with limited conditions of load and displacement, and built up finite element analyzing model of left and right Crankcase Box.2. Analysis and question solution were done to Crankcase Box with I-DEAS Master Series TM6.0 integrated software. Stress graph,distortion graph and stress distortion graph had been gained. Three improved projects on original structure were put forward. In order to reduce the stress and distortion of Crankcase Box, the method of adding flange thickness and enlarging protrusion width together with augmenting tendon was presented. An example validated that the method was available. Author validated corresponding stress and displacement of original material aluminium alloy in working condition.3.Finite element dynamics analyzing model of Crankcase Box's system structure was built up, and computed anterior ten ranks intrinsic frequency and vibrant graph character of left and right Crankcase Box with Lanczos method. The conclusion that in working condition syntonic phenomenon can't occur in the Crankcase Box was came to. 4.Finite element dynamics analyzing model of left and right Crankcase Box and its three improved structures' dynamic response were established, and dynamic responses of all kinds of structures were computed with the method of vibrant graph congruence using I-Deas software. The vertical librating acceleration relative time and vertical speed relative time graphs of Crankcase Box's surface were obtained...