Spherical involute straight-tooth bevel gear pair and tooth profile modification method thereof

Abstract

The invention discloses a spherical involute straight-tooth bevel gear pair and a tooth profile modification method thereof. The spherical involute straight-tooth bevel gear pair comprises a driving gear and a driven gear, wherein the driving gear meshes with the driven gear, and the tooth profile of each gear is divided into two segments, an AB segment is a theoretical spherical involute, a BD' segment is a spherical surface modification curve, and a B point is the modification starting point. The tooth profile modification method of the gear pair includes the following steps of software modeling, manufacturing of a profile modification mold and mass production. According to the spherical involute straight-tooth bevel gear pair, tooth profile modification of the driving gear and the driven gear adopts the method of tooth top profile modification at the same time; and the profile modification curve is a curve on the spherical surface on which the spherical involute lies, the profile modification direction is the direction of the spherical involute normal line, the profile modification starting point and the profile modification quantity can be optimized and obtained according to the finite element algorithm, the engaging-in and engaging-out impacts of the gears are reduced, vibration and noise are reduced, the meshing quality the gear pair is improved and the service life of the gear pair is prolonged.

Description

technical field [0001] The invention relates to the technical field of gear design and manufacture, in particular to a spherical involute straight bevel gear pair and a tooth profile modification method thereof. Background technique [0002] The transmission ratio change during gear meshing is considered to be one of the sources of gear vibration and noise. In order to ensure a constant transmission ratio, the tooth profile curve of the spur bevel gear pair should be a spherical involute; however, due to the transmission characteristics of the spherical involute I don’t know much about it. Straight bevel gears are generally modeled with back cone involutes. Although the back cone involute is very close to the spherical involute and the modeling is convenient, there are always errors in this modeling method. When the spherical radius The smaller the ratio to the gear modulus, the greater the error; the smaller the ratio of the spherical radius to the gear modulus of the strai...

AI Technical Summary

Problems solved by technology

[0002] The transmission ratio change during gear meshing is considered to be one of the sources of gear vibration and noise. In order to ensure a constant transmission ratio, the tooth profile curve of the spur bevel gear pair should be a spherical involute; however, due to the transmission characteristics of the spherical involute I don’t know much about it. Straight bevel gears are generally modeled with back cone involutes. Although the back cone involute is very close to the spherical involute and the modeling is convenient, there are always errors in this modeling method. When the spherical radius The smaller the ratio to the gear modulus, the greater the error; the smaller the ratio of the spherical radius to the gear modulus of the straight bevel gear in a car differential, the greater the tooth profile error, and the resulting change in transmission ratio The vibration and noise caused will be obvious; at present, although the batch forging of spherical involute bevel gears for differentials has not yet been realized, the transmission of spherical involute bevel gears is better than that of plane involute bevel gears. The advantages of it make it a hot spot in the research and development of universities and enterprises;

[0003] Due to the existence of loaded elastic deformation, when the gear pair engages in and out, the base joints of the planet and the half shaft are not equal, that is, the interference between the gear pair and the engagement occurs, which brings the vibration and noise of the gear pair. There have been some studies on tooth profile modification of open-line straight bevel gears. The common point of these studies is that the theoretical spherical involute is drawn in the 3D software, and the modified part is replaced by a straight line, parabola and other planar curves. The advantage is that the image is intuitive. It is easy to design, but the disadvantage is that the amount of modification and the direction of modification cannot accurately reflect the deformation direction and size of elastic deformation, and there may be problems of excessive or insufficient modification

Images