Analysis Of Unstable Layer Of Carbon Film Sprayed By Potentiometer And The Development Of Its Removal Equipment

Potentiometer is an important feedback sensor widely used in aerospace servo control systems.The quality of the carbon film processing of the resistive diaphragm that affects the precise control of the servo system in the production of the potentiometer is important.However,the current potentiometer production process is completely dependent on manual manufacturing,lacking the optimal process parameters for the automatic spraying proces s.At the same time,the formation mechanism of the unstable layer formed by the carbon film drying process during the potentiometer spraying process has n't been explored.It is urgent to clarify the formation mechanism and develop an effective unstable layer removal device instead of the traditional manual removal.In this way,the production costs are saved and production efficiency is improved.Firstly this thesis started with a specific atomizing nozzle and analyzed the resistance liquid atomization spraying process.Based on FLUENT,the flow field model at the nozzle exit and the jet field model downstream of the spray gun were established;In addition,through the discretization of the Euler wall liquid film model,combined with Matlab,the wall liquid film thickness solver for the carbon film layer prepared by resistive liquid atomization spraying was developed,which can simulate and calculate the linearity of the actual spray preparation resistive film.In this way,the theoretical optimal process pa rameters were obtained through simulation experiments.Secondly,on the basis of ensuring the uniform distribution of the components of the carbon film obtained on the substrate during the preparation process,the distribution of graphite and phenolic resin particles in the liquid film after 1 h in high temperature environment was simulated.Through the analysis of the obtained results,a mechanism model of unstable layer formation was established.Thirdly,the current process of manually removing the unsta ble layer was studied,and the corresponding technical solutions were proposed and the overall design requirements of the device were clearly removed.Through the modularization of the removal function,the mechanical,electrical and control schemes of the overall removal device were designed and the structural design rationality analysis was carried out.Finally,the orthogonal test of the optimal parameters for the automatic spraying equipment was designed and carried out at the production site.The optimal process parameters for guiding the production were obtained and the correctness of the model established above was verified.At the same time,the microscopic surface morphology analysis of the carbon film layer was carried out,and the resulting unstable layer formation mechanism model was verified and corrected by the obtained data analysis.According to the developed unstable layer removal device,combined with the actual removal process,the adjustable process parameters were quantified,and the optimal process parameter combination was finally determined by designing and performing the optimal parameter determination test.