Design And Analysis Of EXPEC 1230 Portable Near-infrared Analyzer

Near Infrared Reflectance(NIR) spectroscopy is a new detection technology,compared with traditional chemical analysis technology,Near Infrared Reflectance Spectroscopy has many technical advantages of high efficiency,fast,environmental protection,precision and so on,all countries are eager to develop this detection technologywhich has a wide range of applications in agriculture,industry,science and technology and other fields.This thesis has discussed the research and design of the new near-infrared analyzer which has the advantages of simple structure,light weight and stable performance.The main research contents and results of this paper are as fllows:1)The design scheme and requirements of the whole machine were established.Modular design for the machine,the simplification of the mechine structure subsystem whichwas an important embodiment of the whole machine portability,so as to establish the design goal and direction.2)Completed the design and analysis of the spectrometer which was the core part of NIRS analyzer.According to the optical requirements,designed the crank-rocker mechanism of the grating base;The fitting tolerance and the service life of the three bearings were calculated;The three-phase analysis of the grating size and the calculation of the dimension chain were carried out.The deviation of the grating center position between-0.415 and +0.745 mm,The assembly gap between the grating seat and grating form 0.1 to 0.28 mm.3)According to the actual conditions,with the help of the finite element analysis software ANSYS,the thermal and structural couplinganalysis of the spectrometer frame was completed.When the spectrometer frame around the 0.5Mpa pressure and temperature difference between inside and outside 70 degrees,the maximum equivalent stress was 199.81 Mpa.4)The improved design of the light source structure module and the reference disk positioning module was completed,simplified the structure is and improved the positioning accuracy.The light source module not only reduced a structure,but also simplified the production line assembly process,improved the assembly efficiency and reliability.The structure of the reference disc was repositioned to improve the positioning accuracy and reduce the error.through the selection and calculation bythe synchronous belt transmission system,obtained several important parameters of small pulley teeth,the belt circumference,the number of large gear teeth and so on.Through comparison and analysis of the window glass test,it was concluded that the quartz glass wae better than the tempered glass in the spectral absorption rate.5)By measuring several important parameters of the analyzer,together with the measurement of the soybean seed composition,it was concluded that the EXPEC 1230 has stable performance andreliable data.