Research On On-Machine Detection Technology For Profile Accuracy Of Double-Headed Screw Rotor

With the rapid development of my country's machinery industry,various screw machinery products have been widely used.As an important component of large screw machinery products,the screw rotor manufacturing methods have been developed from the previous forming method to disc milling and whirling milling.The manufacturing efficiency has been greatly improved.Correspondingly,higher requirements for the machining accuracy of screw rotors have been put forward.Because accurate measurement technology of screw rotor profile accuracy is an important factor to determine its machining accuracy,on-machine measurement technology with unique advantages such as high measurement accuracy,small error and high measurement efficiency is widely used in the measurement of screw rotor profile.In this paper,the on-machine detection technology for the profile accuracy of the double-headed screw rotor is studied.The specific content is as follows.Firstly,the measurement principle of laser triangulation method and the measurement principle of the double-headed screw rotor profile are described.According to the appearance characteristics of the double-headed screw rotor,an on-machine measurement scheme of the double-headed screw rotor profile based on the laser displacement sensor is designed.According to the designed measurement scheme,the appropriate experimental equipments are selected to construct the on-machine detection system for the profile accuracy of the double-headed screw rotor based on the laser displacement sensor,so as to realize the acquisition,transmission and processing of the profile data of the double-headed screw rotor.Then,in order to avoid the shortcomings of the traditional wavelet threshold function in the process of noise reduction,aiming at the phenomenon that the actually collected double-headed screw rotor profile data contains noise,an improved wavelet threshold function with adjustment parameters based on the hyperbolic tangent function is constructed.The particle swarm optimization algorithm is used to find the optimal value of the adjustment parameters in the improved wavelet threshold function,so that the improved wavelet threshold function can determine its final form according to different actual signals,and obtain a better noise reduction effect.Subsequently,in view of the problem that the data obtained from the on-machine inspection experiment on the profile accuracy of the double-headed screw rotor cannot represent the complete profile information of the double-headed screw rotor,based on the existing fitting methods,the B-spline curve approximation technology is used to complete the fitting of the double-headed screw rotor profile.At the same time,an improved elite clone selection algorithm is proposed to solve the problem of continuous multivariable nonlinear node configuration in the B-spline curve approximation.Finally,according to the on-machine measurement scheme of the double-headed screw rotor profile,the on-machine detection experiment of the double-headed screw rotor profile accuracy with the LXK100 4-axis screw rotor cyclone milling machine as the carrier is carried out.And the improved wavelet threshold noise reduction method and the B-spline curve approximation method based on the improved elite clone selection algorithm are used in the on-machine measurement system to achieve the high precision and high efficiency detection of the profile accuracy of the double-headed screw rotor.This subject uses the LXK100 4-axis screw rotor cyclone milling machine as the carrier to design and implement a laser displacement sensor-based double-headed screw rotor profile accuracy on-machine detection system,the system can realize the virtuous cycle of processing-detection-compensation of the double-headed screw rotor,detect unqualified workpieces in time,and quickly correct it,improve the processing and measurement accuracy of the double-headed screw rotor,and promote the development of the industry.