| As an important processing instrument for the production of parts of mechanical intelligent equipment,the transmission precision and reliability of digital roller machine determine the key factors for the parts to meet the requirements of machining precision.Therefore,the research on the gearbox gear transmission system of digital roller machine has been paid great attention by many researchers.In order to solve the contact fatigue problem of the gear of the number roller machine,the paper takes the third grade spur gear of the number roller machine box as the research object,based on the finite element dynamics,fatigue life analysis theory,reliability theory,etc.the structure analysis of the key gear of the number roller machine box is carried out.Using ABAQUS was carried out on the gear tooth surface contact fatigue stress finite element simulation analysis,combined with the tooth surface stress and fatigue cumulative damage theory to solve the three different under different loading fatigue life estimation method of numerical value,at the same time on the tooth surface corrosion failure simulation,analyzed the fatigue pitting on the tooth surface of gear reliability,the influence of the gear load strength test platform logarithm rolling contact fatigue life of gear machine tool gear box on the test,the test result analysis of S—N curve is calculated,and compared with the stress life estimation results analysis,A more suitable model for estimating the fatigue life of gears in gear box is obtained.The main conclusions are as follows:(1)the powerful ABAQUS software and the 3D modeling software Solidworks were used to conduct the finite element analysis of the contact fatigue strength of the gear tooth surface.Through the post-processing module of ABAQUS software,the maximum contact stress of the tooth surface under variable load and the curve of the maximum stress over time were obtained,and the results were compared with the Hertz theoretical calculation results to verify the reliability of the multi-body dynamic simulation results.(2)according to different estimation methods of gear fatigue life,combined with the contact stress of tooth surface obtained by multi-body dynamics simulation,the fatigue life of simulated gear under three different models was estimated.Three kinds of gear fatigue life,namely nominal stress-life,stress-strain life-life and fatigue damage mechanical life-life estimation,are introduced in detail.(3)multi-body dynamics simulation software was used to establish the tooth surface pitting simulation model of the third stage spur gear,and the reliability of gears with differenttooth surface pitting shapes and radii was calculated.The results show that the size of cylindrical pitting defect and the shape of pitting defect have a significant influence on the gear reliability.the more complex the pitting type,the more edges and corners,and the lower the reliability.(4)the gear load strength tester was used to conduct the contact fatigue life test on the gear of the logarithmic rolling machine,the test results were analyzed and calculated to obtain the S—N curve,and compared with the life estimation results of the stress method,it was found that the life estimation model of the local stress strain method was more reliable. |
PDF Full Text Request