Development Of Control System For Large Gear Measurement

With the rapid progress of the machinery industry,the manufacturing precision of large gears is constantly improving.How to inspect the accuracy of large gears with low cost and high efficiency is a problem that needs to be solved urgently.Tooth pitch deviation,as an important indicator of gear accuracy testing,directly affects gear transmission,and is one of the necessary inspection items for gear accuracy testing.In this thesis,combining the technical difficulties in the large gear detection process,a large gear tooth pitch deviation measuring instrument is designed.Based on the theory of the relative method,the large gear is measured side by side on the machine.Using this measurement method to improve the accuracy and reliability of the gear pitch deviation detection,the design goal can meet the measurement requirements of a large gear with a diameter of 5000 mm.The main work content is:(1)A principle of on-machine measurement of relative normal pitch deviation is proposed,and the mechanical structure of the gear pitch deviation measuring instrument is designed,and the control system is developed on the basis of the mechanical structure.The control system is mainly divided into three parts: motion control,data acquisition and data processing.(2)Complete the software development on the LabVIEW platform,design a data acquisition program with stable signal and short sampling period and a motion control program with high repeat positioning accuracy and fast response speed.And design a generous and concise human-computer interaction interface on the front panel of the program to intuitively output measurement data.(3)Study the influence of the trigger position error on the measurement result of the pitch deviation and analyze the factors that affect the trigger position error.The curve is established with the displacement and time of the sampling point as coordinates,and the measurement value corresponding to the target starting point is found by an interpolation calculation method to improve the measurement accuracy.(4)Complete the calibration of the measurement system to draw the actual offset of the probe and the scale factor of the measurement data.Take the gear deviation measurement experiment on the CNC machine in the mode of the gear.The maximum deviation of the large gear teeth deviation measuring instrument is observed,and the reliability of the measurement results is verified.At the same time,the three-coordinate gauge measurement the teeth deviation of the rack,compared the two sets of measurements,verify the accuracy of the measurement results.