Stress Calculation And Multi-parameter Sensitivity Analysis Of High-Order-Close Gear

Gear is an important part of the mechanical transmission process,whose performance directly determines the longevity of stable operation of the transmission system.Different from traditional involute gear’s convex-convex meshing,high-order close gear is the latest gear configuration method to realize the convex-concave conjugate meshing.The new type of gear applies the concept of touch-to-contact,which can effectively solve the problem of too large contact stress of the involute gear during the contact process,thereby the contact strength of the gear transmission is reduced and the working life of the transmission system is improved.Based on the theory of high-close contact,this paper elaborates the steps and methods of constructing high-order close gear with four involute segments.At the same time,based on the finite element method,the gear meshing contact stress analysis of high-level close gear is carried out and compared with the traditional involute gear under the same conditions.Finally,sensitivity analysis based on response surface method is used in high-close-order gear contact stress with multiple random parameters.The main contents of this paper are as follows:(1)Based on the observation and analysis of plastic deformation and natural formations after long-term operation of heavy-duty gear,the tooth profile curves of the close gear and rack are designed.At the same time,three initial independent parameters that affect the tooth profile are discussed,and the reasonable ranges of the construction parameters are calculated.The close gear meshing with the rack cutter is obtained by using the basic law of close conjugate meshing.The design of the high-close-order gear model was completed.The high-close-order gear was parametrically modeled based on ANSYS APDL language.(2)Comparing the higher-close-order gear with the traditional involute gear in the aspects of the integrated curvature radius,the sliding rate and the bending stress to obtain the differences in transmission performance.The finite element method is used to analyze the bending stress of high-order close gears.The distribution of stress in tooth width direction and gear displacement deformation are obtained.(3)Because the size of the contact stress is directly related to the stable and long-life operation of the transmission system,based on the theoretical calculation of the contact stress between the high-close-order gear and the traditional involute gear,finite element analysis of gear meshing contact is done in order to compare the transmission performance of two typesof gears more accurately.Four-tooth meshing finite element analysis model of high-close-order gear and involute gear are established.Comparing and analyzing the contact stress between two types of gears under the same working conditions and boundary conditions,the advantages and disadvantages of the two types of gears in transmission performance are analyzed.(4)Based on response surface method and Monte-Carlo method,sensitivity analysis of gear meshing contact stress under multi-random parameters of high-order close gear is carried out.Quantitatively get the correlation degree between the high-close-order gear meshing contact stress and different parameters and also get the mathematical formulas between contact stress and parameters.All these provide the theoretical reference for the design and optimization of the high-close-order gear structure.