Virtual Measurement Method Of Gear Transmission Error Based On Gear Point Cloud Data

Gears are widely used parts in modern industry.They are widely used in aerospace,automobiles,wind power generation,high-speed rail and other fields.They are regarded as symbols of modern industry and are embedded in the national emblem.The quality of the gear directly determines the various indicators of its host performance,including vibration noise,transmission accuracy,reliability and fatigue life,etc.Therefore,there are different requirements for gears in different applications.Gear quality detection can control the processing of gears upwards,and determine the application occasions of gears downwards.Quantitative analysis of gear errors is an important means for people to study gears.The gear measuring center is the most widely used gear measuring instrument at present,which can measure the single deviation of the tooth surface.But the gear measurement center cannot measure the comprehensive deviation of the gear.However,the gear transmission error is an important indicator reflecting the transmission performance of the gear,which conforms to the meshing process of the gear when the gear is actually used.The single-mesh meter is a special instrument for measuring the gear transmission error,but the use of the gear single-side meshing comprehensive measuring instrument to measure the gear has extremely high requirements on the shafting.This method is difficult to measure the transmission error of extremely large modulus gears and extremely small modulus gears.How to obtain the transmission error from the single deviation has become an important direction for the development of gear measurement.In this thesis,a virtual measurement method for calculating gear transmission error based on gear point cloud data acquired by optical sensors is proposed.According to the principle of gear meshing,a method for judging the contact of the tooth surface of the discrete point cloud is proposed.By analyzing the single-tooth meshing process and the multi-tooth meshing process,the gear transmission error is calculated.The feasibility of the virtual measurement method proposed in this thesis is verified by comparing with the theoretical simulation of gear contact analysis and carrying out actual measurement experiments of gears.The main research contents of this thesis are as follows:(1)A new method to obtain the gear Single flank composite deviation is proposed.The meshing of the product gear and the theoretical gear is simulated on the computer,and the Single flank composite deviation of the gear is calculated.The method adopts the minimum rotation angle method to establish the contact model between the point cloud data of the gear surface and the theoretical gear equation.Using this method,the Single flank composite deviation curve of the top edge meshing stage,the involute tooth profile meshing stage and the top edge meshing stage of the meshing out can be obtained.As long as the three-dimensional point cloud data of the gear surface is obtained,the single-mesh transmission process of the gear can be simulated in the computer,and the transmission error curve of the gear can be obtained.(2)A new method to obtain the transmission error of the gear pair is proposed.Simulate product gear meshing with product gear on the computer.The method adopts the interpolation method to construct the error tooth surface model,and establishes the contact model of the point cloud data of the driving gear tooth surface and the driven gear tooth surface point cloud data.Through the point cloud data of the tooth surface of the driving wheel and the driven wheel,the transmission process of the product gear can be simulated in the computer,and the transmission error curve of the gear pair can be obtained.This method can predict the transmission characteristics of product gears and provide guidance for gear pairing.(3)Design the virtual measurement software of gear transmission error.On the basis of establishing the virtual measurement model of Single flank composite deviation and the virtual measurement model of gear pair transmission error,the virtual measurement software of gear transmission error is developed.The software provides a new method for obtaining gear transmission error.By inputting the point cloud data of the gear surface into the software,the transmission error curve of the gear can be obtained.Using this software to calculate and obtain the gear transmission error curve greatly improves the efficiency and reduces the cost.