Research Of Solid Modeling And Virtual Assembly Technology For Electrical Products

Drawing is the language of engineers. In the nineteen sixties, people began to use CAD software to design graphics. Early CAD software used simple two-dimensional block instead of the actual complexity of electrical parts to improve the speed of drawing. But the two-dimensional design can't show the structure of product intuitively, it can't assemble the device, optimization, interfere, numerical simulation of temperature field, motion analysis and other advanced computer-aided design work also, Those facts require us to create three-dimensional solid model parts and then assembly. Implementation and operation of the objects are highly consistent with the actual production situation, you can reflect the true product assembly process directly so that the simulation results with high confidence.With AutoCAD platform, Object ARX 2000 SDK for re-development tool, Visual C++6.0 Object-oriented high-level development language, using custom entity class to establish three-dimensional part model of electrical products the virtual assembly system is developed. The part which draw out by this method of three-dimensional solid modeling is equivalent to AutoCAD entity inside. This entity can make the property of production and geometric expression combined to form a fully integrated, simple, excellent performance. through the parametric method, the users can input any parameters to design the parts of different sizes and properties. it greatly saves the designers time for a large number of duplication of effort in electrical engineering design . And three-dimensional solid can be observed from different parts of visual angle, reflecting the geometric and physical properties of entities total.Virtual assembly use three-dimensional solid modeling to emulate real parts assembly process is the typical application in the engineering design of CAD technology. In the process the virtual assembly, two types are divided: the occurrence of collinear restraint and coplanar restraint. Users need to select the relationship information, through geting the vector and other informance of reference components, the target parts can be rotated,shifted to achieve automatic assembly。In the assembly process, the problem of tolerance cause by the triangular patch model, precision Machining accuracy and material shoud be considered. The tolerance levels and the materials are obtained from the database. We should test whether the assembled parts will collide with other parts, If interference doesn't occur, complete assembly, or stop running。In this paper, the author make the drawing and assembly of three-dimensional map of DC electromagnet as an example, using custom entity class to set parameters and create three-dimensional graphics, showing the steps of automatic assembly and methods, achieves the purpose of interference detection of assemble parts.