Research On Generating Method And Error Compensation For Digital Gear Tooth Surfaces

The Digital Gear Tooth Surfaces depicted with dynamics feature differ from the surfaces described on the basis of ideal rigid body in that the former can accurately reflect the elastic and plastic deformation induced by stress and heat in machine operations, thus improve the performance of the gear drive to meet the real requirements of high speed, heavy load, high efficiency and low noise. The research about digital gear tooth surfaces is becoming an important developing aspect for contemporary design & manufacture. It is difficult to generate digital gear tooth surfaces accurately by traditional manufacturing technology. In order to machining digital gear tooth surfaces with high efficiency, great accuracy and remarkable flexibility, researches on generating method and error compensation for digital gear tooth surfaces have been thoroughly carried out in this dissertation. The work covers: (1) Research on generating method of digital tooth surfaces. Combined with the digitized theory of conjugate surface and the actual technologies for gear machining, the method to manufacture the digital tooth surface is developed. The machining models of gear grinding and shaping for digital gear tooth surfaces are established. The research offers the basic theory and means to manufacture digital gear tooth surfaces practically. (2) Research on virtual manufacture of digital tooth surfaces with generating method. A simulation generation system like gear grinding is taken as an example to develop, which can verify the model of gear grinding and the generating method of digital tooth surfaces. At the same time, the checkout of continuity, accuracy and interference during the processing can be done. The simulation provides helps to the experiments of gear machining. (3) Research on error analysis of machining of digital tooth surfaces. The method for extracting machining errors from the information of topography measurements on the real surfaces of physical parts is proposed. The distribution of error on the total tooth surface is analyzed and evaluated. A synthetical error model has been developed, and suitable algorithms have been presented to calculate errors. The software for error analysis is also developed. (4) Research on error compensation of machining of digital tooth surfaces. A 'pre-calibration error compensation'strategy is presented. The total compensation error is predicted based on this idea. A virtual digital surface is reconstructed with the prediction. This work offers the numerical value in the subsequent operations. Then, the software for error compensation is developed. (5) Research on experiments of generating machining of digital tooth surfaces. Gear shaping experiments as examples are carried out. Some factual questions such as gear continual meshing are treated with during the experiments. The gear with digitized involute tooth profile and the gear with digitized non-standard tooth profile are slotted successfully. The experiments verify the generating method of digital gear tooth surfaces proposed in this dissertation. (6) Research on slotting experiments of digital tooth surfaces based on error pre-compensation. The Gear with digitized involute tooth profile is taken as example during the experiments. The digital gear tooth surfaces are slotted successfully by the operation with error pre-compensation. The results of accuracy checking of this gear are illustrated and proved the researches mentioned above. The dissertation develops the systematic theory for generating machining of DGTS, hence breaks through the limitation of the traditional approaches based on analytic geometry. The research combining the processing techniques of gear with the technologies of digital measurement, NC machining and computer software, realized the manufacture of gear with high quality. The method presented can be directly applied in the manufacture of the digital design tooth surface and the machining of measuring reconstructed digital surface of the physical parts as well. The research provides theoretical and technical bases for the CAD/CAM technology for manufacturing of digital gear tooth surfaces.