| Mechanical press, an appliance widely used for material plastic forming, enables several processes such as punching, extrusion, forging, which plays an important role in auto industry, aviation industry, hardware, light industry.As an operating mechanism general used by modern mechanical press, the multi-linkage mechanism is the key part of achieving some technique properties, including drawing, curving, whose level of design can directly affect the function of the operating mechanism. Furthermore, the property of the press such as efficiency, working quality can be influenced in turn. Eight-bar linkage is one of it used successfully hungering for enforcing design and product optimization. Based on the optimization method and the computer progress design, the multi-linkage mechanism optimization design is an effective one of methods to solve the complex design problem. During the period of product designing, the motion simulation of mechanical press can examine the operating mechanism's working rationality and the collision among its components. Meanwhile, the operating mechanism can be analyzed directly and optimized so as to perfect the function of operating mechanism. Therefore, the optimization design and motion simulation of Mechanical press multi-linkage have become the important contents of press design.Based on reviewing and summarizing the current research situation of the mechanical press optimization design and motion simulation, taking eight-bar linkage as an example, the general mathematical expressions of the whole motion process are made up, and explore and select the reasonable method of optimization on linkage. The optimization design with complex optimization method and the computation of the motion performance parameters of the linkage are carried out.The specific application technologies of optimization, such as the establishment of mathematical model, the ascertainment of objective function, the determination of the constraint conditions, the selection of the optimization method, are elaborated. The optimization methods of eight-bar linkage are determined by comparing main optimization methods. The motion of operating mechanism is analyzed. Inner and outer sliders of the mathematics expressions on displacement, speed, acceleration and the crank angle are established, which can provide mathematics foundation for the optimization design and motion simulation of linkage.The complex optimization method is multipurpose used as optimization method. whose objective function is the forming speed of inner slider keeping a lower, fixed value and the displacement of outer slider keeping a lower value. Performance parameter is proved after optimization.The multi-linkage optimization design and motion simulation software is developed by using Visual C++ 6.0, which provides a useful tool for design multi-linkage, and can examine not rationality of the design but the interference of each bar and the rationality of parameters. |
