The Design Method Of Structure Configurations-Performance-Size For Complex Supporting Members

With the rapid development of China's economy, the manufacturing industry is faced with higher requirements put forward by enterprises. How to achieve fast and highly efficient design in a short time has become an urgent issue in parts design. At present, most structure designs of complex supporting members depend on experience analogy or local improvements. Traditional design method, however, may cause a waste of parts materials as well as increse the design cycle greatly. Since the design method of complex supporting members is a weak point globally, further study of it is of great significance.This paper studies the design method of structure configurations-performance-size for complex supporting members based on the structure "concept-unit " design method which is applied by the research group of "the optimizing tools and norms for the design of complex supporting members of CNC machines". It is a sub-project of the "key technologies, tool set development and typical product application of the high-end CNC machines digital design" (NO.2015ZX04014-021), a National Science and Technology Major Project. This puts forward the quantitative design method based on qualitative research, presents detailed design process, and proves the validity of the method by an example. The main contents are as follows:1 Based on the basic unit configuration qualitative design method, the paper summaries the basic structure of the unit under different loads, optimizes the basic structure unit size, studies the geometrical features and considers the structures under different loads as basic structure units. The variables of frame sizes of each basic structure unit are optimized for a reliable design database.2 Research is carried out on the layout forms (number, size and arrangement) of the internal basic structure units of complex supporting members. Basic structure units are grouped into composite structure units to study their performance optimization under typical conditions. Composite structure units are categorized into different types according their load features under various conditions. Aimed to achieve static optimal performance, the bearing internal structure optimization layout scheme is determined with consideration given to different types of composite structure units and the size- performance of basic ones and the number, size and permutation and combination order of basic units adopted as the variable.3 Taking the column of vertical machining center for example. Its design involves the proposed design methods. With the maximal displacement of the supporting member taken as the static performance evaluation index and a comparative analysis conducted in the performances of the original and new schemes, the column weight in the new scheme is reduced by 1%and its maximal displacement decreases by 12%.