Research On 3D Parametric Design Technology Of Transmission Parts

With the continuous development of 3D CAD technology,3D drawing plays an increasingly important role in the design process of mechanical parts modeling.2D engineering drawings are still widely used due to technical deficiencies in the processing of parts.The information expressed in two-dimensional drawing often does not have the intuition of information expression in three-dimensional space,and has high requirements on the three-dimensional imagination of manufacturing personnel,which slows down the rapid design and production efficiency of products.Drawings of mechanical design products also have many borrowing phenomenon,which is precisely because the product structure,each component by a number of components,even if the type of components and the components is different,but most of the components parts are interchangeable.It is necessary to make coordination and general optimization for the part sizes during the designing process of the actual products of transmission parts.The existing SolidWorks software can realize the three-dimensional annotation function,but the three-dimensional annotation function often has the problems of repeated operations,complicated interfaces and inconvenient usages in the call.Therefore,in order to realize the purpose of drawing quickly and automatically with the change of structure,size and environment during the designing of products,parametrization idea is particularly important.The thesis presents the characteristic technology and database technology through the analysis of the characteristics of transmission components.The Visual Basic programming software can be used to make a secondary development and research to SolidWorks to realize the 3D parametric design of transmission parts and improve the design efficiency.It becomes the basement of further delivery of the design information.The concrete research work is as follows:(1)To analyze the composition of the structure of common transmission parts,divide the structure of the transmission parts into a combination of feature blocks and sum up the corresponding typical feature blocks.The methods of 3D spatial feature expression and combination of feature blocks are proposed to realize spatial integration expression of geometric features and geometric tolerance characteristics of transmission parts and lay a foundation of automatic design of 3D parameterization for transmission parts.(2)To make secondary developed software based on characteristic block of transmission parts combining with the characteristic of friendly interface of Visual Basic6.0 and the strong 3D design ability of Solid Works.The 3D part model design of transmission parts is realized to reflect detail design information such as geometric size,surface roughness,reference,shape and position tolerance,etc.(3)The data(on tolerances,keyways,etc.)used in characteristic block library and design of transmission parts is established by application of database technology and embedded in the previous two development software.It saves the design time and improves the design efficiency.(4)Through the designing examples,the reliability and feasibility of the software is verified.The 3D structure design of transmission parts and the annotation automatic visual system proposed in the thesis completely reflect the 3D space model information of the parts and make the foundation for further delivery and manufacture of the following part information.