Research On 3-D Topological Modification Technology Of Inner Helical Gear Under Load Conditions

Planetary gear trains are often used in wind power generation,ships,helicopters,precision machine tools,etc.due to their compact structure,large transmission ratio,high transmission efficiency,large bearing capacity and stable transmission.However,they were subject to installation errors and gear teeth deformation from bearing and other factors,edge contact occurs,meshing impact,generating vibration and noise,reducing the service life of the gear pair.The gear modifing technology can improve the meshing performance of the planetary gear.In order to eliminate the adverse effects caused by the inconsistency of the outer helical planetary gears,the internal helical gear was taked as the research object,based on forming grinding theory of the inner helical gear,The 3-D topological modification of the inner helical gear was carried out.The influence of the different modification curves and modification quantities on the meshing performance of the inner helical gear pair was studied by the tooth contact analysis and finite element analysis technology.The contact condition of the modified inner helical gear pair under the installation error condition was discussed.Machining topologically modified inner helical gears and verifying the feasibility of the modification theory by rolling test.Specific research contents are as follows:1.Based on the principle of inner helical gear forming grinding,the 3-D topological modification topography was completed by the tooth profile and tooth direction modification method of the inner helical gear,and the mathematical model of the shaped grinding was established,and the topological modified internal helical gear and the standard external helical gear tooth surface equation was derived,using programming technology to solve the discrete tooth surface coordinates,and establish a 3-D model of the inner helical gear pair.2.Based on the principle of coordinate transformation and gear meshing,the mathematical model of the tooth contact analysis of the inner helical gear was derived,and the program was compiled and solved.The different shaping curves and shape modification were applied to the tooth surface contact area and the transmission.The influence of the error was completed,and the acquisition of the better topological shaped tooth surface was completed.3.Taking the second-order parabola modification curve as an example and selecting different tooth profile and tooth direction modification coefficient,the corresponding gear 3-D model was established by UG software.The five-tooth meshing model was used to carry out the inner helical gear pair in Ansys Workbench.The finite element bearing contact analysis was used to analyze the influence of the shaping coefficient on the meshing performance of the inner helical gear pair by comparing the tooth surface contact area and contact stress.4.Based on the actual installation conditions of the inner helical gear pair,the installation error of the parallelism of the axis was defined.The meshing mathematical model of the inner helical gear with the installation error was established.The X direction and Y were studied by the tooth contact analysis and finite element bearing contact analysis.The influence of the direction parallelism error on the meshing performance of the inner helical gear pair was studied.5.Taking a pair of inner helical gears as an example,the model of inner helical gears with topological modification was established.The simulation processing was carried out in VERICUT,and the processing program was compiled.The feasibility of the modification theory was verified by the NC machine tool processing of inner helical gears with topological modification and the rolling test.