| It follows from the comparison of many kinds of CAD/CAM software and the analysis of characteristics on parallel indexing cam mechanism that Pro/E is the most reasonable software for developing platform. Developing environment was established by means of Pro/E, Pro/TOOLKIT, Pro/Program and Visual C++.The coordinate equation of parallel indexing cam profile was derived by means of relative motion method and isometric curve theory. Cam profile formed by enveloped curve fully and that formed by enveloped curve partially have been analyzed. Conditions of non-interference are: (1) Curvature radius is not less than roller's radius if curvature center of definite point is on the out side of profile. (2) Derived number of indexing profile is continuous.Conditions of continuous transmission for parallel indexing cam mechanism are: (1) There is at least 1 roller engaging with each cam disc at any time. (2) There is at least 1 roller in cam driving zone.Pressure angle equation was educed. According to the analysis of pressure angle for parallel indexing cam mechanism, the greater the radius of roller rr , the greater the pressure angle is. The greater the radius of rollers distributed circle rd , the smaller the pressure angle is. The smaller the addendum radius of cam R a, the smaller the value range of pressure angle.It follows from the analysis of kinemics that angular displacementθand angular speedωof Gutman are similar with shoes of quasi-cosine. The angular acceleration of Gutman is smoothly continuous. There are breaks for angular acceleration of quasi-cosine. That is distinct between two kinds of driving rule.During dynamics analysis, parallel indexing cam mechanism has been simplified as input subsystem and output subsystem. Engaging point is the boundary of the subsystems, which are coupled by displacement and forces exerted each other at this point. Input system and output system were simplified as one-freedom system respectively, which consists of equivalent moment of inertia, equivalent stiffness and equivalent damp. Dynamic response equations have been established. Evaluation formula is presented based on numerical computation theory. Dynamic simulation of mechanism system has been done. It follows from dynamic analysis that the influence of input speed on maximum swing is too little to take into account. Input speed influences the shape of vibration output graph because of the change of dynamic load frequency. The smaller the stroke angle, the more violent the vibration is. The maximum swing of quasi-cosine is less than that of Gutman. At the end of Gutman indexing, vibration shanks much more sharply than the case of quasi-cosine.The architecture of CAD/CAM system has been established. Function for every module das been designed and implemented. During the development of CAD module, forming process of cam profile and computing of data for cam profile were discussed in details. The frame of CAD subsystem and the implementation of part modeling and assembly were introduced.During the development of CAM module, the CAM subsystem was implemented by means of dynamic link libraries program based on database Access and VC++. It was loaded in menu form for Pro/E system to be called back.Finally, the system CAD/CAM for parallel indexing cam mechanism was established. The implementation of information transfer and information sharing between the subsystems can improve the degree of integration and automation on design and manufacture for parallel indexing cam. So, the developed CAD/CAM system is a excellent software platform for parallel indexing cam mechanism desin, manufacturing and dynamic behavior research.
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