The Case-Based Reasoning Design And Realization Of Gear Reducer3d Cad Design System

Reducer is a closed device of transmission applied between prime mover andworking machine, which primarily functions to increase torque and lower speed, inorder to drive machines with large torque. According to the traditional way of thinking,gear reducer designs are usually for certain specific products, from parts to assemblies,and the dimensions of the geometric model designed is usually fixed. The structure anddimensions of parts cannot be modified flexibly in accordance to needs, and designershave to redo the heavy and similar calculation included in the design, and sketch thecorresponding geometric models again. Consequently, due to lack of inheritance in thetraditional way of design, the cycle of a new product design would be too long. Themethod of case-based reasoning in design has been applied gradually in the field ofengineering design in recent years and it is growing fast. Its core idea is reuse of humanexperience. When a designer receives a new task of design, he/she would first come upwith design samples they worked on previously that are similar to the one they areworking on at present. Differences between them are recognized, and the previousdesign is then modified or rearranged. With respect to the principle of design, a newsolution is born. Case-based design attempts to recur the process with the help ofcomputers.In this thesis, with respect to the above problems, the case-based reasoning methodof design is taken as the object of study. Based on analysis of current researches fromboth domestic and overseas sources, together with examples of gear reducer, we put theemphasis of our study on the key techniques and solutions of the design. The maincontents of the study are as follows:1.Parametric-feature modeling method is applied in modeling of example of gearreducer. A library of3D modeling of examples of gear reducer is established. A studyof expression of examples and the structure organization of the library is conducted aswell.2.Based on the analysis of traditional researching algorithms, new algorithms arestudied. With respect to the characteristics of reducers, example searching methods suitable for various characteristics are proposed.3.The evaluation methods of examples are studied. Interference examination isadopted for the assembled parts in aid of the function of virtual assembly and analysisof UG NX. A general methodology is given for evaluating the assembly.4.The case-based reasoning designing method of gear reducer3D CAD designsystem will be given, with application of technology in combination of case-basedreasoning and product design in the gear reducer design. With the platform of3Dsoftware, a simple model of case-based reasoning gear reducer3D CAD design systemis developed.