Error Analysis And Modification Research Of Line Contact Spiral Bevel Gears

Aiming at the problems of in and out impact and edge contact in the meshing process of line contact spiral bevel gears,on the basis of finite element analysis of bevel gear meshing with error,a new method of line contact bevel gear modification is presented,in order to achieve higher meshing performance of spiral bevel gears in the theoretical design stage.In this paper,a tool head approximation machining method for line contact conjugate meshing is introduced firstly,and a 3D model of gear pair is established based on this method.Then the influence of installation error and pitch error on the contact of line contact spiral bevel gear transmission is analyzed by using finite element software,and the influence rule of error on transmission contact is summarized.Finally,aiming at reducing transmission error fluctuation and edge contact,the tooth surface modification design of spiral bevel gear is carried out.The main contents of this paper are as follows:(1)The mathematical model of machining tooth surface of line contact spiral bevel gear pair was established.Based on the research results of the method of tooth surface approximation for line contact bevel gear put forward by the research group,the mathematical model of machining tooth surface of spiral bevel gear pair is given.(2)The modeling and finite element simulation analysis of line contact spiral bevel gear pair were carried out.the three-dimensional model of line contact bevel gear pair were established,and the meshing process of gear pair was detected and analyzed by finite element contact simulation,which proved the correctness of the model.The finite element software was used to study the variation rules of contact force,contact degree,contact area,rotation Angle of gear and pinion and transmission error under different loads.The meshing performance of gears under different loads was compared.(3)The contact influence of error factors on line contact spiral bevel gear transmission was analyzed.Firstly,3d model of line contact spiral bevel gears with machine tool adjustment parameter error were established,and the influence of machine tool adjustment parameter error on gear transmission contact were investigated by using finite element software.Then,based on the ideal condition of no error in tooth topology,the influence of large axis error,pinion axis error,shaft spacing error and tooth pitch deviation on meshing transmission of line contact spiral bevel gears under different accuracy levels were analyzed.The influence rule of the error on the gear is obtained,which provides theoretical basis for tooth surface modification design.(4)The research on tooth surface modification design of spiral bevel gear was carried out.In order to solve the problems of in and out impact and edge contact in the meshing process of gear,a method of line contact spiral bevel gear modification was proposed.The tooth surface of pinion which is completely conjugate with the tooth surface of large gear is taken as the reference tooth surface and the tooth surface of pinion is modified.Firstly,the characteristic points of tooth surface modification are determined,and the method of determining the modification quantity of characteristic points is studied.Then the modification area of the tooth surface was determined,and the modification amount of the modification area was determined by quadratic polynomial.Finally,an example is given to verify that the maximum contact stress of modified spiral bevel gears decreases obviously.