Study On The Principle And Technology Of Laser Measurement Of Rotor Helical Surfaces

With the rapid development of our country equipment manufacturing industry,all kinds of screw mechanical products with the spiral screw drill and screw motor as the representative come into being.But there is a certain gap between the production of spiral mechanical products and the same industry in foreign countries,mainly because of the machining precision in the domestic design type helical products and products on the shortcomings.In the case that there is no a major breakthrough in the line type design,how to improve the manufacturing precision of spiral products has become the key to restrict China’s industrial development level.And the processing accuracy cannot do without accurate measurement,so the research on the measurement of complex spiral curved parts becomes more and more important.Nowadays there are two main measurement of rotor helical surface contact and non-contact,for the ultra slim screw rotor using oil drilling industry,the traditional measurement method is using a micrometer to measure the large diameter and small diameter of screw rotor,and through the profile model of the advance of the quality assessment of the actual processing of screw rotor that not only increases the labor intensity of the workers,and the precision can not be guaranteed.The laser triangulation method is a new non-contact measurement method developed in recent years,which is widely used in the fields of three dimensional contour because of its superior properties.First of all,through the research on the measurement principle of rotor helical surface geometry and laser triangulation method,it is determined that the rotor helical surface in machine measurement system.The system is based on the LXK300 X numerical control spiral groove milling machine with intellectual property developed by Shenyang Science and Technology Development Co.,Ltd,through adding high precision laser displacement sensor rotary encoder,computer and other equipment in milling to realize the rotor section profile data acquisition,transmission and storage.Then,combined with the screw rotor profile characteristics and experimental data characteristics,the existing data processing methods are compared.In the case of analyzing the noise reduction of traditional wavelet threshold denoising method with the noise reduction is not completely effective,deleted signal in the process,and a new wavelet threshold denoising method is proposed;It is large fitting problems that piecewise curve fitting in subsection fitting function is not continuous,not smooth transition and polynomial curve fitting on the data points,a truncated method of rotor curve fitting based on Lagrange multiplier method is proposed.At last,it is analyzed that the reason of the errors produced in the measurement machine measuring system,and a careful study of the influence factors in the influence of inclination error factor is made,starting from the principle of laser triangulation technique,the mathematical model of angle error is established according to the geometric characteristics of the optical path,and the mathematical expression of angle error is derived.Finally,in the existing CNC machining center,it is to achieve calibration of angle error of the laser displacement sensor in the experiment with high precision laser interferometer as a benchmark.This research aims at the study of rotor helical surface on machine measurement,to reduce the labor intensity of workers,to improve the rotor helical surface machining precision and efficiency,to improve the service life of domestic screw machine products work efficiency,and to promote the development of China’s industry.