The structure model of the multi axis CNC machining center was introduced. The multi-axis programming, post-processing methods and machining examples based on the typical CAD/CAM software UG were proposed, and the axes of a double-swing five axis linkage machine were described. The coordinate transformation relationship has developed a post-processing system that provides a reference for the formulation of a multi-axis linkage machining program.
1 Introduction
One of the trends of modern advanced machinery manufacturing technology is the complexity and precision of the product's shape structure. On the one hand, in order to meet the dynamic performance requirements, the shape and structure of aviation and aerospace products are often very complex; on the other hand, in order to meet people's personalized and aesthetic needs, some civilian products (toys and decorations) are of a strange design. Provides opportunities and conditions for the wide application of multi axis CNC machining technology. Because compared with the traditional processing methods, multi axis CNC machining technology has obvious advantages in manufacturing complex shapes. For example, a single card can process multiple surfaces of complex parts, and it can guarantee high accuracy under certain conditions. effectiveness. At present, the application of multi axis CNC machining technology still faces many difficulties. For example, the processing objects are often complex in shape, and the programming of the five axes itself is abstract and complex, and the operation is also complicated. In addition, the lack of experience in multi axis machining processes can be followed. It is difficult to achieve universal multi-coordinate programming. Therefore, the processing of multi-coordinate machining in the programming system generally adopts a special-purpose component approach.
2 Multi axis CNC machine tool structure model
As a representative of a multi axis machine tool, a five axis linkage machine can theoretically process parts with any complex surface. Therefore, the study of the five axis linkage machine tool's structural model can not only understand its principle of motion, and thus contribute to the specific machine structure and parameters, the preparation of a complete post-processing program, and can be extended to more axis structure, movement the way. At the same time, three axis and four axis machine tools can be regarded as special forms of five axis machine tools, which are easier to understand and apply.
The five axis linkage machine generally consists of three translation axes plus two rotary axes. According to the specific structure of the rotation axis, it can be divided into three types: double swing of the tool, double rotation of the worktable, and tool swing plus rotation of the worktable. It is defined that the axis where the normal vector of the rotation axis is constant is the orientation axis, and the axis where the normal vector of the rotation axis changes is the direction change axis. Because the five-axis machine tool double-swinging machine has the characteristics of table and moving axis, it can process large-scale and complicated curved parts, and it is easy to achieve excellent high-speed performance. This article is aimed at such machine tools.
