Automobile structural parts refer to the bearing parts or load-bearing parts in the automobile, which are closely related to automobile safety. In the automobile body, many structural parts are installed on the nodes of the body structure and connected with other structural parts to form a deformation resistant high-strength frame. Due to the complex structure and high precision requirements of these parts, they are usually produced by multi station progressive die. Although the progressive die for automobile structural parts has many advantages, such as high production efficiency, saving material cost, good product accuracy and so on, the combination of the structural characteristics of the progressive die and the complex forming process of automobile structural parts makes the structure of this kind of die complex and the size is, which greatly improves the difficulty of die design and manufacturing. Of course, it takes three months or even longer for a pair of progressive dies for automobile structural parts from design to delivery, and designers need to accumulate rich design experience in practice to be competent. The analysis and calculation of the whole design process are complex, need to be modified repeatedly, and the design work efficiency is low, which can not meet the requirements of the market for product renewal.
With the development of domestic automobile market, enterprises are eager to improve the efficiency and quality of mold design. At present, some die CAD systems have been used to assist progressive die design, but from the use effect, these systems have the problems of low degree of integration, specialization and customization, which are difficult to meet the requirements of progressive die design of automobile structural parts. The reason is that due to the complex structure of automobile structural parts, the corresponding progressive die usually includes multi-channel stations such as punching, trimming, bending, forming and so on. Working components composed of punch, die, standard parts, plate inserts and other parts on each station complete the corresponding processes. However, the existing mold design system usually focuses on the design of individual parts. By providing a series of parts design tool sets, users can use them by themselves to assemble the required working components. Although this design idea reduces the coupling between various functions in the system, it also ignores the real correlation between various parts in the working assembly in the design process of progressive die.
Therefore, according to the design points of progressive die for automobile structural parts, aiming at the design difficulties of this kind of die and the shortcomings of the existing progressive die design system, this paper puts forward the rapid generation and relevance editing method of progressive die working components, and develops a set of intelligent design and modification function module system of punching and trimming components of progressive die for automobile structural parts based on NX platform. The system has been put into use in enterprises and achieved good results.
On the basis of analyzing the structural characteristics of progressive die for automobile structural parts, sorting out the typical blanking structure and design principles of standard hole blanking, special-shaped hole blanking, trimming, tongue cutting and other processes, and comprehensively applying the idea of global parameter management, parametric and modular design, rule-based reasoning, dynamic assembly and other technologies, the punching and trimming function module of progressive die is developed on Siemens NX 8.5 software platform. As shown in Figure 3, the tool is divided into global component generation tool and rapid parameter editing tool. The user first initializes the shared parameters in the component design process according to the global parameter management tool, then carries out the structural variant design through the component rapid generation tool, and finally uses the component editing tool to adjust and edit the detailed features.