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MaximumPermissibleErrorofFullSurfaceContactErrorJMPE[JISB7502:2016]Thefullsurfacecontacterroroftheoutsidemicrometerisanindicationerrormeasuredbycontactingtheentiremeasuringsurfacewiththeobjecttobemeasuredatanarbitrarypointinthemeasuringrange.Thevaluecanbeobtainedbyadjustingthereferencepointusingaconstantpressuredevicewiththeminimummeasuringlengthofthemicrometer,insertingagrade0or1gaugeblockprescribedinJISB7506oranequivalentorhighergagebetweenthemeasuringsurfaces(Fig.3),andthensubtractingthedimensionsofthegaugeblockfromtheindicationvalueofthemicrometerusingaconstantpressuredevice.GaugeblockFig.3:MeasurementoffullsurfacecontacterrorMicrometerPerformanceEvaluationMethodJISB7502wasrevisedandissuedin2016astheJapaneseIndustrialStandardsofthemicrometer,andthe“Instrumentalerror”indicatingtheindicationerrorofthemicrometerhasbeenchangedto“MaximumPermissibleError(MPE)ofindication”.The“Instrumentalerror”oftheconventionalJISadoptsacceptancecriteriathatthespecicationrange(precisionspecication)equalsacceptancerange,andtheOK/NGjudgmentdoesnotincludemeasurementuncertainty(Fig.1).The“MaximumPermissibleError(MPE)ofindication”ofthenewJISemploysthebasicconceptoftheOK/NGjudgmenttakingintoaccounttheuncertaintyadoptedintheISOstandard(ISO14253-1).Thevericationofconformityandnonconformitytothespecicationsisclearlystipulatedtousetheinternationallyrecognizedacceptancecriteria(simpleacceptance)whenthespecicationrangeequalstheacceptancerange,anditisacceptedthatthespecicationrangeequalstheacceptancerangeifagivenconditionconsideringuncertaintyismet.TheabovesaidinternationallyrecognizedacceptancecriterionisISO/TR14253-6:2012(Fig.2).ThefollowingdescribesthestandardinspectionmethodincludingtherevisedcontentofJIS2016.Fig.1ConventionalJISInstrumentalerrorJISB7502-1994SpecificationrangeNon-conformityrangeConformityrangeNon-conformityrangeAcceptancerangeUncertaintyisnotincludedinjudgmentSpecificationrange=AcceptancerangeFig.2NewJISMaximumPermissibleError(MPE)JISB7502:2016(ISO/TR14253-6:2012)Non-conformityrange(Rejected)UUSpecificationrangeConformityrangeAcceptanceNon-conformityrange(Rejected)UUUncertaintyrangeUncertaintyrangeWhenaconditionconsideringuncertaintyissatisfiedSpecificationrange=Conformityrange02-82
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