【作者】 张志伟；

【导师】 王金刚；

【作者基本信息】 河北工业大学 ， 机械设计及理论， 2004， 硕士

【摘要】 提高推土机的操纵性能，改善驾驶员的工作环境，是推土机的发展方向之一。集中连杆操纵机构取消了传统的转向、变速及换向操纵杆，将转向、换向与变速操纵功能集成在一根操纵杆上，利用肘关节的自然动作控制操纵杆实现转向、前进后退和变速。 虚拟设计作为一种新型的设计方法，能够实现产品的参数化设计、三维造型、分析检测，可以在设计阶段发现产品的不足，并加以改进，从而提高设计效率和设计质量，降低成本。因此，将虚拟样机技术应用于设计中具有重要的现实意义。 本论文使用机械系统运动学/动力学仿真分析软件ADAMS(Automatic Dynamic Analysis of Mechanical Systems)对设计的新型推土机集中连杆操纵机构进行了运动学仿真分析，精确测量了存在的联动角度。在对原来操纵机构中的关键零部件重新建立模型的基础上，建立了新的虚拟样机。对新的虚拟样机中影响联动角度的关键点进行了参数化建模和优化设计，使联动角度大幅度降低。为了提高模型程序的通用性，应用ADAMS的二次开发模块，将交互界面添加到ADAMS中。用户可以通过选择ADAMS主菜单中的“Lever Transfer”条目，在交互式对话框中对各参数进行选择、修改或重新设置，方便地得到新的设计方案。 在连杆机构的设计中有一些结构是根据经验公式设计的，所以对最终设计结果，需要进行进一步的分析。在本论文中，采用了UG的有限元分析模块，对设计的关键部件——操纵手柄进行了有限元分析。分析中采用的模型是设计所得的手柄三维模型。在预处理中对手柄进行合理简化，定义材料、载荷与边界条件，划分网格，然后进行有限元分析求解，得到变形和应力等的分析结果，并在后处理模块中进行结果的输出。分析结果为物理样机的试制和改进设计提供了依据。更多还原

【Abstract】 It is one of the development directions for bulldozer to enhance its maneuverability and improve driver’s labor circumstances. Manipulate mechanism with concentrative link lever integrates functions , such as steering N shift and operating direction , into one operating lever. With this mechanism, driver can realize all the operations of bulldozer using elbow joint’s action.As a new kind of design method, virtual design can accomplish parametric design, 3D modeling, analysis and detection, etc. It can find defects of products in the designing phase. Through this method, the design can be modified and improved. The efficiency and quality of the design can be enhanced, too. And the cost can be reduced accordingly. It is significant to apply the virtual design technology in design.Through the using of ADAMS (Automatic Dynamic Analysis of Mechanical Systems) , kinematics simulations, which are based on the designed new type manipulate mechanism with concentrative link lever, are executed. Interferences lying in the former model are measured accurately. A new virtual prototyping model is reestablished after pivotal parts were rebuilt in ADAMS. Key points in the new virtual prototyping model, which affecting interferences, are parameterized and designed optimally, so the interferences are reduced sharply. In order to improve the generalization of model, graphic interfaces are concentrated through the development of ADAMS. Users can select "Lever Transfer" in the main menu of ADAMS, and then get new design plans expediently by choosing modifying or resetting parameters in relevant graphic interfaces.In the process of the design, some mechanisms are obtained according to experiential formulae, so the ultimate results need to be analyzed further. In this article, the operating handleis made finite element analysis by finite element analysis part of UG. The analyticed model is based on the relevant part of UG, and the handle has been simplified reasonably in preprocess. After material, load and boundary conditions being defined, the model’s mesh is generated. Through finite element analysis, the results of deformation and stress can be obtained; at the same time the results can be exported from the postprocessor. The analytic results provide the basis for trial-manufacture of physical prototyping and betterment design.更多还原