| Globoidal cam mechanism are the key driving device in the automation. They have the advantages of cramped constructions and reliable performances, and have had a widespread availability in the area such as light industrial machinery, textile machinery, NC machines, etc.. However, the complexity of the structure make it very difficult to design and machine. Presently, the design and manufacture level of the globoidal cam at home has fallen behind that in abroad and Taiwan. The globoidal cams made in China have some drawbacks such as bad bearing capacity, unreliable performance, short service life, etc., which have restricted the market application of the globidal cam mechanisms seriously. Thus, deep researches on the theories of the globoidal cams design and manufacture, and the exploitation and application of the globoidal cam mechanisms CAD/CAM/CNC integrated techniques are all of great significance to widen the application about it. Therefore, in order to improve the machining quality and to optimize the design method, this paper has developed some techniques on tool path optimization, and an elastic deformation static analysis method based on FEM has been proposed, too. Finally, a globoidal cam mechanisms CAD/CAM/CNC integrated system has been exploited in this paper. The main research works are as follows:1) The present situation and problems to be solved on researches of the globoidal cam mechanisms have been analyzed and summarized in this paper. Then the design and manufacture foundational theories of the globoidal cams have been generalized roundly, the machining methods and traits of the globoidal cams have been summed up, too. Especially, the universal NC machining technics schemes have been analyzed deeply.2) Based on the analysis of the programming errors when using a conventional toolpath planning with a uniform step-size, the paper has built a new toolpath planning with a non-uniform step-size to confine chord error and an adaptive-feedrate interpolation for the globoidal cams machining. The research work includes the design of the programming flow for the generation of toolpath with a non-uniform step-size, the algorithm deduction, and the definition of G-code formats for the globoidal cam adaptive-feedrate interpolation. and an example for machining simulation has been introduced to validate the algorithms proposed in the paper. 3) As for the design demand of the globoidal cam mechanisms, a elastic deformation static analysis method based on FEM has been analyzed. By analyzing the load conditions during the tooth transmission, the finite element analysis model has been constructed, then, the calculation flow has been designed. An example has been analyzed with the finite element software MSC.Marc.4) A globoidal cam mechanisms CAD/CAM/CNC integrated system has been exploited based on the researches above in this paper by using VC++ 6.0 and UG/Open API as the developing tools, The system have some functions such as 3D solid modeling for both the intermittent indexing globoidal cam mechanisms and the continuous indexing globoidal cam mechanisms, four-axis and five-axis NC machining process simulation, the cutter location data and NC codes generation, and the serial data transfer between the personal computer and NC machine.In a word, the researches in this paper have some significances. Firstly, two methods of toolpath optimization for the globoidal cam NC machining proposed in this paper can provide a theory foundation for the globoidal cams machining with high speed and accuracy. Secondly, the limit bearing capacity prediction method based on the elastic deformation static analysis is more accurate than that based on empirical estimation of the designer. The lastly, the globoidal cam mechanism CAD/CAM/CNC system exploited in the paper can supply an available and synthesis software platform for the design, manufacture and farther researches of globoidal cams.
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