| Gear is widely used in mechanical transmission. It has been developed for more than500years. Undercutting restrict the gear size. Aiming to avoid undercutting of gears, bigger drivespace is required. Space curve meshing wheels (SCMW) overcomes undercutting, andpromotes the development of gear transmission technology.This dissertation is focused on enhancing SCMW’s transmission precision. Firstly, Basedon selective laser melting manufacturing technology, electrochemical brushing (ECB) hasbeen studied to improve the surface quality of SCMW for transmission precision. Secondly,during the meshing of SCMW, assembly errors and load will lead transmission error. Theinfluence of the assembly errors, load and contact ratio on the transmission precision werestudied. And then, appropriate solutions to improve transmission precision have beenproposed.The main content of this dissertation is as follows.1. The ECB manufacturing technology was studied. The cathode tools and finishingexperimental rigs were designed, and the finishing devices were designed to processSCMW samples. The transmission precision was improved by improving the surfacequality of SCMW.2. Effect of assembly errors on transmission precision was studied. Equations of SCMWsurfaces are obtained according to the space curve meshing theory. Based on the toothcontact analysis (TCA), parameters of the actual contact curve are solved, and thetransmission errors and the actual contact ratio are obtained. Investigation providestheoretical reference and measurements for controlling and reducing transmission errors.3. Effect of load on SCMW transmission precision was studied. During the SCMW meshingunder load, stress and deformation of the meshing tines were studied, and the actualsurface equations of the meshing tines were obtained. According to the TCA results, thetransmission errors were simulated by MATLAB. Aiming to improve the transmissionprecision, a modification program of the meshing tines was proposed relying on theresults of the deformation analysis.4. Effect of contact ratio on SCMW transmission precision was studied. Firstly, effect ofcontact ratio on load distribution was studied. Then, effect of contact ratio on deformationof meshing tines was studied according to the load distribution. Finally, the transmissionerrors were obtained by TCA. Investigation provides theoretical reference for designingcontact ratio. Although much work has been done on improving the transmission precision of SCMW,there are still some improvements needed to do. Such as friction and lubrication which areimportant factors of impacting on the transmission precision of SCMW. |
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