Gantry Crane Three-dimensional Structure Of The Variable Drawing Cad System

Gantry crane,widely used for lifting goods in the open air is an important type of elevating machinery and owns many serial products. The traditional two-dimensional design now can not meet the increasing requirements of modern crane design since its long-term cycle development and abstraction. With the development of computer science and three-dimensional graphics,the trend of mechanical design has been towards to three-dimensional CAD inevitably.To complete three-dimensional Variational design for structures of a gantry crane, the secondary development of SolidWorks software,based in the analysis of structure characters and design process of gantry crane,in accordance with SolidWorks API by using Visual C++ in windows operating system,is researched in this thesis. In addition,since there are many flaws in the shifting process from three-dimensional models to two dimensional drawings,AutoCAD secondary development according to SCR(script)file using Visual C++ is also researched for two-dimensional parametric drawing.In the part of three-dimensional Variational modeling,SolidWorks and Visual C++ are used united. Firstly,three-dimensional parts'models are built with SolidWorks;secondly,with the help of application programming interface of SolidWorks and programs coded in Visual C++,parts'models are driven completely. Based on the result of science calculation,data files are input so that the sketch of model and characteristic parameters can be changed hence the models changed too. For the consideration of coming finite element analysis to models,some big components of gantry crane such as main beam,upper-crossed beam,supports,saddle are built as entireties correspondingly without links between plates. The CAD soft developed in the project can drive SolidWorks externally,which means,it is an executive file rather than an adding in SolidWorks. In the part of two-dimensional parametric drawings,SCR(script) file is adopted as a programming interface to realize the secondary development of AutoCAD. Script files,generated from programs in Visual C++,can drive AutoCAD so that two-dimensional parametric drawing is achieved.As one important module of gantry crane CAD software,this drawing module can build three-dimensional models and two-dimensional drawings automatically. Also,three-dimensional models can be used for dimensional interference inspection and finite element analysis and as visual images in bidding showing to users. Two-dimensional drawings are guidelines in the manufacturing of crane for shop floor. Working time is shortened in programming by taking SolidWorks and Visual C++ united as development tool. It is helpful for finite element analysis through building three-dimensional model such as main beam,upper-crossed beam,supports, saddle as entirety. In a word,it is more convenient for users when using the drawing module.The thought and method adopted in this paper,which will increase design efficiency and shorten cycle of product development,can be regarded as an important reference resource for other types of crane design.