Research On Some Key Problems In Small Modulus Gear Visual Measurement

Generally,the small modulus gears are the gears with modulus less than 1mm.Small modulus gears are widely used in IT,mechnical electronics,instruments and other fields.As key parts,the gear quality may directly affect the accuracy,noise and life span of the main engine.Therefore,to ensure the quality of the main engine,it is necessary to measure the precision of the small modulus gears.Compared with contact measurement,high speed non-contact measurement of precision parts by visual measurement is one of the development trends in the industrial field.This dissertation researches on the system calibration,deviation evaluation,software development and other key problems in visual measurement of small modulus gear.Main contents of this dissertation are as follows.(1)The calibration method of the small modulus gear vision measurement system is researched.The dot calibration plate is used to calibrate the pixel equivalent of the system.(2)The measurement results of basic parameters of small-modulus gear are given based on visual measurement,which include tooth number,addendum radius,tooth root radius,modulus and gear center coordinates.On this basis,the sub-pixel scatter data of tooth profiles are obtained.According to ISO 1328-1:2013,evaluation methods for the pitch deviations and profile deviations are determined.(3)Based on C# language and Halcon software,the visual measurement software of small modulus gears is developed,which has the function of gear basic parameters measurement,gear pitch deviations and profile deviations evaluation,and measurement results display and saving.(4)Calibration experiment is carried out to obtain pixel equivalent.The condition of luminance of light source in the experiment is determined.The measurement results of gear basic parameters,gear pitch and profile deviations are obtained in the experiment.The results are compared with the measurement results of a gear measuring center.