Research On Independent And Smooth Weight Loading Method And Device For100KN Primary Force Standard Machine

Dead-weight primary force standard machine is the equipment for national forcemeasuring and testing. It recurrents the gravity force of the standard weight on force sensor bysomeway, so as to measure the performance of force sensor. China’s dead-weight primaryforce standard machines were mainly built in sixties or seventies of the last century. Theyhave made great contribution to the development of economy and the progress of science andtechnology. However, due to the backwardness of science and technology at that time, thereexists rigid impact and "inverse process" phenomenon when loading or unloading thestandard weight. The rigid impact affects the performance of the sensor or even damages itwhen serious. Since many sensors are made of strain theory, their output exists lags. The "inverse process" phenomenon lows down the efficiency of calibration. As it is uncontrollable,it cannot provide a same environment for calibration. So it affects the precision of calibration.Therefore，the performance of the traditional dead-weight primary force standard machinecannot meet the demands of high efficiency, precision and stability for force measuring today.In order to reduce the rigid impact and "inverse process" phenomenon during the periodof loading or unloading the standard weight，and to reduce the influence to the sensor whencalibrating and to improve the accuracy and efficiency of calibration.China testingtechnology research institute commissions our institute to do a secondary transformation for100KN dead-weight primary force standard machine.The research of my thesis is based on the secondary transformation for100KNdead-weight primary force standard machine. After the analysis for the working principle andstructure of the traditional dead-weight primary force standard machine, the problems arefound out and a new loading method—independent smooth loading method is proposed. Forthe purpose of independent smooth loading, the overall designing plan of the independentsmooth loading system is researched, the related theories of the independent smooth loadingmethod are analyzed, the mathematical model of smooth loading is built and the simulationexperiments are done. In this thesis, the working principle of the independent smoothloading and unloading device is designed, and the general principle plan of the independentsmooth loading and unloading device is determined, the structure design of the loading andunloading device is completed. The structure analysis of the key parts are done by means offinite element analysis method, the working reliability of the parts is verified. Finally, thesecondary transformation and calibration tests of the100KN dead-weight primary forcestandard machine are done, the theory of the independent smooth loading method is proved tobe right.In this thesis, the independent smooth loading method for dead-weight primary forcestandard machine is proved to be feasible by means of theoretical analysis and simulationexperiment, and the design of the independent smooth loading device is done so the secondary transformation for100KN dead-weight primary force standard machine iscompleted successfully. The function of independent smooth loading and unloading isrealized. The performance of the traditional dead-weight primary force standard machine isgreatly improved. New vitality is added to the improvement of the primary force standardmachine technology, and that is a important significance for the improvement of the forcemeasuring technology.