Method, system, device and medium for measuring gear tooth profile roughness

A system for measuring gear tooth profile roughness, comprising an obtaining module, a measuring module, a calculating module, a fitting module, a length-determining module, a filtering module and a parameter determining module, wherein,

• the obtaining module is configured for obtaining design parameters of a target gear pair and test parameters of each tooth profile working point when a driving gear and a driven gear in the target gear pair are meshed;
• the design parameters comprise a teeth number of the driving gear, a teeth number of the driven gear, a modulus, a modification coefficient of the driving gear, a modification coefficient of the driven gear and a pressure angle;
• the test parameters comprise torque of the driving gear, rotating speed of the driving gear and a center distance between the driving gear and the driven gear;
• the measuring module is configured for taking any one of gears in the target gear pair as a target gear, and measuring a tooth surface characteristic line of the target gear in a tooth profile direction to obtain a measured surface profile;
• the tooth surface characteristic line is a tooth profile line determined according to each tooth profile working point when the driving gear and the driven gear are meshed;
• the calculating module is configured for calculating the tooth surface characteristic line of the target gear in the tooth profile direction according to the design parameters to obtain a theoretical tooth profile curve;
• the fitting module is configured for fitting the measured surface profile and the theoretical tooth profile curve to obtain a surface structure curve;
• the length-determining module is configured for calculating a Hertzian contact width of each tooth profile working point in a working area on the theoretical tooth profile curve according to the design parameters and the test parameters, and determining an evaluation length of surface roughness corresponding to each tooth profile working point according to the Hertzian contact width;
• the filtering module is configured for filtering the surface structure curve by means of a filter with a set wavelength to obtain a surface roughness profile;
• and
• the parameter determining module is configured for determining surface roughness parameters of each tooth profile working point in the working area according to the surface roughness profile for each evaluation length;
• the surface roughness parameters are configured for characterizing a bearing capacity of the target gear in the working area.