>> P.260
Accuracynotationchange(RegardingMPEnotation)Accuracynotationchange(forcustomproducts)TheISO13385-1:2019andJISB7507:2022standardstipulatestheaccuracynotationforcompliantproducts.However,nothingisstipulatedforcustomproductsthatarenotcompliantwithsaidstandard(suchascaliperswithdedicatedmeasuringfaces),sofortheseproductsthenotationofaccuracyislefttothediscretionofeachmanufacturer.Mitutoyo,withmanycustomcalipers,describesMPEforallofitscalipersbasedonthefollowinglineofthinking.Forexample,MPEis“ScaleShiftError(SMPE)”for“caliperswhosemeasuringfaceisotherthanthezero-settingface=caliperswithexclusivemeasuringmethod”suchascenterlinecalipers,insidecalipers,etc.(Fig.5,Table7)AccuracyisdescribedusingSMPEmeasurednotusingthenumberoftestpointsstipulatedintheISO13385-1:2019andJISB7507:2022standard,butratherwiththesamenumberoftestpointsandtestingmethodasbefore.(Fig.5)Non-ISOmodel(Ex.)573-605-20573-646-20◀Zero-settingfaceNooutsidemeasuringface▲Pitchmeasuringunit(SMPE)(Table7-1)Maximumpermissibleerror(MPE)EMPE(mm)—SMPE(mm)±0.04◀Zero-settingfaceNooutsidemeasuringface▲Insidemeasuringunit(SMPE)(Table7-2)Maximumpermissibleerror(MPE)EMPE(mm)—SMPE(mm)±0.03Numberoftestpoints:3Numberoftestpoints:3The“instrumentalerror”useduntilnowwillchangeto“MPE(EMPE/SMPE)”.ScaleShiftError(SMPE)willdescribethepermissibleerrorincludingthosefordepthandstep.(Table4)StandardsISO13385-1:2019EMPEOutsidemeasurementAccuracynotationforoutsidemeasurementISO13385-1:2011(JISB7507:2016)AccuracynotationforoutsidemeasurementInsidemeasurementSMPEDepthmeasurementStepmeasurementI.D.measurementPermissiblevaluesincludingthoseforallmeasurements:inside,depth,step,etc.measurement=InsideEMPEDepth,step,=EMPE+0.02mmMaximumpermissibleerrorincludestherepeatabilityandquantizingerror.Depthmeasuringunit(SMPE)▼Smallholemeasurement(SMPE)▼TestpointsandMPEnotation◀Insidemeasurement(SMPE)Outsidemeasurement(EMPE)◀◀◀Stepmeasurement(SMPE)▶Ex.)200mmcaliper(Table4-1)Accuracy±0.02mm(conventionalnotation)BreakdownOutsidemeasurementInsidemeasurement±0.02±0.02Fordepthandstepmeasurement,add0.02mmtotheoutsidemeasurementvalue.SMPEisdescribedformeasurementsotherthantheoutsidemeasurement,butthemaximumpermissibleerrorforinsidemeasurementremainsthesameasbefore.Thepermissiblevaluesformeasurementsotherthantheoutsidemeasurement(inside,depth,step,andinsidediametermeasurement)mustbedescribedasSMPEinlinewiththeISO13385-1:2019andJISB7507:2022standard.Sincethepermissiblevaluesfordepthandstepmeasurementarelargerthanthoseforinsidemeasurement,thiscouldgiveanimpressionthataccuracyhassuffered.However,thisissimplyduetothechangeofnotationinaccordancewiththeISO13385-1:2019andJISB7507:2022standard;neitherhastheaccuracyoftheinsidemeasurementdeterioratednorhastheproductperformancechanged.(Table6-1,6-2)(Table6-1)Measuredlength50orlessOver50,100orlessOver100,200orlessOver200,300orless➡Unit:mmScaleinterval,graduationorresolution0.02or0.01±0.02±0.030.05±0.05±0.06±0.07±0.08±0.04Note:EMPEincludesthemeasurementerrorarisingfromstraightness,flatnessandparallelismofthemeasuringsurface.MaximumpermissibleerrorEMPEofPartialsurfacecontacterrorinJISB7507Ex.)Permissiblevaluesfora200mmcaliper(Table6-2)MaximumpermissibleMeasuredlengtherror(MPE)(mm)EMPE(mm)SMPE(mm)0≤L≤5050≤L≤100100≤L≤150150≤L≤200±0.02±0.04Ex.)BreakdownofSMPEInsidemeasurementStepmeasurementDepthmeasurementI.D.measurement±0.02±0.04±0.04+0.01-0.0304-47
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