Research On Loading Methods For Load Cell's Load Characteristic Test

Loadcellisonekindofsensors,itistheinstrumentthat canoutput electricalsignalthat certain corresponding relations with the load, in fact it is the sensor surveyedfor the strength or the mass, it has been used widely in the strength survey, thetransmission, the calibration and in the weigh technology. load cells probably tooccupy 30% in all shares in the domestic sensor market, now its annual outputabout600million, loadcellswereutilizedmoreandmorewiderin the productions,thelife,thescientificresearchandso onundereachkindofenvironmentnowadays,moreover the demand to load cells is also increase in high speed, we can foreseethat the output of load cells will be bigger in the future.But at present the testingtechnique is still to use the static loading method according the verificationregulation of load cell, the examination efficiency is lowly and the cost is high, itcannotadaptthepresent statusthemassproductioninproduceof the load cells,thedevelopmentofproduction needs toseekahigher efficiencytesting method.Inthisarticle the non-generic loading method has been advanced on the foundation oftraditional static loading test method and has validate the two methods throughexperiments.Themaincontentofthisarticleisasfollow:1. summarized the load cells function and the characteristic, elaborated severalkinds of common load cellscategory and its precision, application scope andso onas well as thepresentdevelopmentstatus andthetendencyofload cellsin domestic and foreign, the testing technique status at present in domesticand foreign of load cells, advance the non-static loading test method in thefoundationofstaticloadingtest。2. Analysis the rationality and the feasibility of the non-static loading testmethod, had proven thatthe non-static loadingtestmethod can completes theload cells characteristic test under the precondition of ensuring precisiondemand when read and processing method according the given method in aenough low speed and in enough short area nearby the standard forcevalues ,and use high speed dynamic loading method by motor in other loadarea,this loadingtest method need not high quality instrument ,and it did notneed the static stable controlled process for loading machine. Thus it canreduce the loading system construction cost, And can enhance test workingefficiencywithnotaffecttheworkprecision。3. Introduced the structure and work principle of the building-up loading testsystem for load cells make up of by building-up force standard machine,point out the ladders loading testing method this non-static loading testmethodand validated the feasibilitythrough experiments, also has confirmedthe faster loading method is a feasible non-static loading test method. theladders loadingmethod is one appropriate non-staticloading testingmethod,It can use the existing testing facility fullyand only need set different valuethat enter low speed loading phase and the instrument sampling frequencyaccording different measuring range load cell and the instrument, accordingtothecertainprocessingmethod,theladdersloadingmethod canenhance testefficiency greatly with not affect the work precision, it has the importantpracticalsignificanceandtheapplicationvalueto theloadcellproduction。4. Inordertoverifywhethercan reduceloadinggradespotintheloadingtestingprocess to enhance test efficiency in the condition of insuring the testprecision, analysis the static loading test result of familiar many kind ofstructure type and measuring range load cells, discovered the percentagepositions that load point of corresponding to the biggest load characteristicerror in the sensor itself measuring rang has the normal distribution, thedistribution mean value is 49.74551%, and 99.25% sample distributes in25%~75% area,all in 20%~75%,so we canreduce loading grade point in thetest, reducestheloadingprogressionsandenhancestestefficiency。5. One kind of new loading test method–flexible loading, was discussed andresearched. it is different with the loading method before in the mostwidespread load cells loading test system that building-up loading system, atthesametimepointout theaccurateloadcontrol decided bythedisplacementaccurate degree that can be achieved in the loading system and the systemstructurerigidity.the flexibleloadingcan ensureandenhanceloading stabilitythrough reduced system rigidity,advance the method reduce system rigidityby using small rigidity element.it enable the loading system be able toachieve fine adjustment strength value,realize a new method that adjustmentload value subtly. adopt putting the air-spring equipment in series in loadingsystem to reduce the system rigidity and do some tests verify the validity offlexibleloading.Above are all key contents of this article, in this article propose several newloading test methods under the precondition that theoretical analysis is feasible,validatethe rationalities and feasibilitythrough the experiment of these methods,these methods all can enhancetest efficiency, saves the production cost, and suitforthemassproduction ofloadcells.