Profile Design And Meshing Characteristics Analysis Of Point-line Meshing Gear

Gears and transmission equipments is an important large category of basic parts inmachinery industry, design and manufacturing of high-performance gear is helpful toimprove the performance and service life of machinery. As a new type of meshing form,point-line meshing gears have more advantages and superior performance comparedwith traditional involute gear. Point-line meshing gear is essential involute gearcomposed with convex and concave meshing tooth profile. Therefore, it contains bothline meshing and point meshing properties and has line contact and point contact duringthe meshing of point-line meshing gear. Point-line meshing gear is adapted to promotein wide use as a kind of high-performance gear. Therefore, the study of tooth design andmeshing characteristics on point-line meshing gear has practical value and goodprospects for development.This thesis studied some key issues such as the meshing theory, design methods,meshing characteristics through theoretical analysis and numerical simulation methodon the basis of summarizing previous work. It is hoped to provide guidance forengineering practice of point-line meshing gear. The main contents are as follows:①Conjugate equation of point-line meshing gear is established based on thegeneration principle of gear tooth surface. Coordinate transformation matrixes arecalculated among the end face of the rack cutter, normal face of the rack cutter and thetooth surface to be machined adopting coordinate transformation method. Accuratetooth surface equation of point-line meshing gear is deduced through the coordinatetransformation of the rack cutter and analysis of point-line meshing gear kinematicrelation. It can lay the foundation for analysis of the gear characteristics and refinedcalculation of Finite–Element-Analysis.②The correct meshing condition of point-line meshing gear is analyzed combinedwith geometry relation of point-line meshing gear transmission. Equations of end toothprofile and momentary contact line are established based on the derived precise toothsurface. The point coordinates of momentary contact line are obtained by MATLABmathematical software programming. Then, the meshing state of end surface and themomentary contact line form during meshing are achieved.③Static analysis of finite element model is established to analyze the Bendingstress distribution of point-line meshing gear. The distribution of bending stress in different meshing transient during meshing process of point-line meshing gear andstandard involute gear are calculated and the draws of bending stress distribution inevery instantaneous engagement along tooth root are obtained. The regularities ofbending stress distribution are compared with the standard involute gear.④Dynamic analysis model of point-line meshing gear is established based on theexplicit dynamic theory. Stress and radial contact force are calculated during momentarycontact. Dynamic meshing characteristics of point-line meshing gear are compared withstandard involute gear.