Research On Micro Hole Rotary Cutting Machining Equipment And Process Of Injector Based On Ultrafast Laser

In the second half of 2020,the National VIb emission standard,which puts forward higher requirements on the fuel atomization characteristics,the micro-hole size accuracy and structure type of the fuel injection nozzle,is fully implemented in China.The technology of processing oil nozzle micro-hole is the key technology.This article independently develops a special system for ultra-fast laser rotary cutting micro-hole processing.It carries out related process optimization and experimental research on the nozzle material of the fuel injection nozzle.The main research work is as follows:(1)The essay describes the theory of ultra-fast laser micro-hole machining.The characteristics of ultrafast lasers as well as the mechanism and the main methods of laser micro-hole processing were summarized.It analyzes the advantages of optical prism rotary cutting system for laser micro-hole processing,and discusses the influence oflaser power,defocus amount,rotary cutting speed and other factors on laser micro-hole processing.(2)The research was study on the development of laser micro-hole processing equipment system.Taking the micro-hole processing requirements of fuel injection nozzles into consideration,the laser processing special intelligent equipment model was established,and a product prototype was developed.The mainly research content includes:carrying out the overall program design of intelligent equipment for laser processing,including the host structure,the laser output laser beam shaping system,the high-precision CCD monitoring system,the light guide focusing system,the high-speed rotary cutting module,the five-axis precision motion platform,the control system and so on;designing and manufacture of micro-hole machining fixtures for typical structure fuel injection nozzles;analyzing the characteristics and accuracy of machining graphics in order to complete the path optimization of special control software and interface functions;establishing the real-time detection system for the processing process;realizing the online detection of the processing quality during the processing process.(3)The research on laser spin-cut micro-hole processing technology was carried out.The influence of laser beam quality,laser power,defocus amount,and cutting speed on the pores of 304 stainless steel was discussed.According to the processing requirements of the micro-holes,optimizing the system parameters including laser output power,rotary cutting speed and so on.The appropriate defocus amount range was obtained through experiments of processing the required micro-aperture size of taper.With the optimization of other parameters,the high-quality micro-holes that met the requirements and processing efficiency were finally processed.Through the exploration of the process test,high-precision micro-hole processing could be achieved,and the efficiency and yield of micro-hole processing could be improved.(4)The laser micropore morphology was predicted by Elman neural network optimized by ant colony algorithm.The main contents include:firstly,the orthogonal experiment method was used to obtain combinations under different process parameters and used as training samples;in the next step,the Elman neural network and the Elman neural network improved by the ant colony optimization algorithm were used to predict the micropore shape;finally the reliability of ant colony algorithm optimization is verified by comparison analysis.