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PrecisionMeasurementTechnology》主講人：趙慧、楊國星TianjinLightIndustryVocationalTechnicalCollegeI

IIIIIIVVVIFundamentalsofCoordinateMeasurementApplication

DimensionalErrorDetectionShapeErrorDetection

DirectionalErrorDetection

PositionalErrorDetectionRunoutErrorDetectionVII

CurveandSurfaceDetectionVIII

ExtendedContentTaskII:BearingInspection[TaskIntroduction]Thedrawingofthebearingcomponentisshowninthefigure.Thiscomponentinvolvesmultiplegeometricerrordetectiontasks,requiringtheuseofacoordinatemeasuringmachine(CMM)toperformtherelatedinspectionsandproduceareport.[RelatedKnowledge]I.CoaxialityTolerance

Commoncoaxialitytolerancenotationandinterpretationareasshowninthetable.ShapetoleranceitemsLabelingExampleInterpretationMeaningofInterpretationCoaxiality

ThecoaxialitytoleranceofthemeasuredcenteraxistothedatumaxisAisφ0.1mm.

Theextracted(actual)centerlineofthelargecylindricalsurfaceshouldbeconstrainedwithinacylindricalsurfacewithadiameterofφ0.1,withdatumaxisAastheaxis.[RelatedKnowledge]II.CoaxialityErrorandEvaluationCoaxialityerrorreferstothedeviationoftheactualmeasuredfeaturefromtheidealfeature.Theacceptanceconditionisthatthecoaxialityerrormustnotexceedthespecifiedcoaxialitytolerance.Inthemenubar,click"ShapeandPosition"→"Coaxiality."The"Coaxiality"iconwillappearunderthe"Characteristics"tab.Double-clicktoopenit,andthe"Coaxiality"dialogboxwillpopup.Themeaningsofeachiconinthecoaxialitydialogboxareshowninthefigure.Inthe"Coaxiality"dialogbox,selectthemeasuredfeatureunderthe"Element"button,setthedatum,andmodifythesymbolandtolerancevaluetocompletethecoaxialityerrorevaluation.[RelatedKnowledge]III.CoaxialityErrorDataAnalysis

Toobtaindetailedinformationonthecoaxialitymeasurementresults,clickon"Resources"→"FeatureSettingsEdit"inthemenubar.The"ProgramFeatureEdit"dialogboxwillappear,asshowninthefigure.Inthedrop-downmenu,select"MorePositionResults"andsetitto"On."Thiswillallowthecoaxiality-relatedcoordinatevaluestobedisplayedwhengeneratingthemeasurementreport,asshowninthefigure.[RelatedKnowledge]IV.SymmetryTolerance

Thecommonnotationandinterpretationofsymmetrytoleranceareshowninthetablebelow.ShapetoleranceitemsLabelingExampleInterpretationMeaningofInterpretationSymmetry

ThesymmetrytoleranceofthemeasuredcenterplanerelativetoreferenceplaneAis0.08mm.Theextracted(actual)centerplaneshouldbeconstrainedwithinaspacingof0.08,symmetricallybetweentwoparallelplaneswithreferencetothecenterplaneA.[RelatedKnowledge]V.SymmetryErrorandEvaluation

Symmetryerrorreferstothevariationoftheactualmeasuredfeaturerelativetotheidealfeature.Theacceptanceconditionisthatthesymmetryerrorvaluemustnotexceedthesymmetrytolerancevalue.

Clickon"ShapeandPosition"→"Symmetry"inthemenubar.The"Symmetry"iconwillappearunderthe"Features"tab.Double-clicktoopenthe"Symmetry"dialogbox,andthemeaningofeachiconinthedialogboxisshowninthefigure.Inthe"Symmetry"dialogbox,selectthemeasuredfeatureatthe"Element"button,modifytheidentificationandtolerancevalues,andthiscompletesthesymmetryerrorevaluation.[TaskImplementation]I.OrganizingMeasurementItems

Organizeandnumberthemeasurementitems,andassignnumberstothemeasuredfeatures,asshowninthefigure.[TaskImplementation]FormationoftheMeasurementItemTableasShownSerialNumberMeasurementItemDescription1Ф37±0.05DiameterofCylinder22Coaxialityφ0.04(DatumA)CoaxialityofCylinder2relativetoCylinder1(DatumA)3Ф42±0.02DiameterofCylinder14Ф80±0.1Diameterofthecircularsectionformedbythecentersofcircles1-45Symmetry0.05(DatumB)SymmetryoftheplaneformedbyPlanes3and4relativetoDatumB[TaskImplementation]II.DeterminingtheClampingSchemeBasedontheprinciplesofworkpiececlamping,theclampingplanasshowninthefigureisadopted,ensuringthatallelementscanbemeasuredinasingleclampingoperation.[TaskImplementation]III.ProbeSelectionandCalibrationForsensorsequippedwitharotaryprobehead,theL58D3probecanbeselected.Inthiscase,probeorientations1_A0B0and5_A180B90shouldbeusedandcalibratedaccordingly.Forfixed-typesensors,stylusconfigurationsNo.1andNo.3withstar-typeprobestructurescanbeselected.Thistaskwillusetherotaryprobeheadsensorasanexampleforexplanation.[TaskImplementation]IV.EstablishingtheBasicCoordinateSystemIntheMeasurementProgramtab,clickonthecorrespondingicontoopenthedialogboxtitled“ReadorModifyEstablishedBaseCoordinateSystem”,asshowninthefigure.Usethedefaultsettingsandclickthe“OK”buttontoopentheBaseCoordinateSystemdialogbox.Accordingtotheelementsindicatedinthediagram,selecttheappropriatefeaturestoestablishthecoordinatesystem.

[TaskImplementation]IV.EstablishingtheBasicCoordinateSystem

Theestablishedcoordinatesystemisdisplayedasshowninthefigure.[TaskImplementation]V.CreatingtheSafetyPlane

Inthe"MeasurementProgram"functiontab,clickonthecorrespondingicontoopenthe"SafetyPlane"dialogbox,asshowninthefigure.Clickthe"PredefineSafetyPlanefromCADModel"button.Inthepop-up"BoundaryDistance"dialogbox,keepthedefaultsettingof10mm.Click"OK"tocompletethecreationofthesafetyplane.[TaskImplementation]VI.DefiningElementsandStrategiesDefinetheelementssequentiallyaccordingtothemeasurementelementnumberinginthediagramandassignmeasurementstrategiesandevaluationsettingstoeachelementasspecifiedinthetable.SerialNumberElementMeasurementStrategyandEvaluationSettingsRemarks1Plane1–Plane5Scanningstrategyormulti-pointstrategy.Evenlydistributedmeasurementpoints2Circle1-Circle4Circularpathscanningwithatleast425points,checkfilteringandoutlierrejection,low-passfilterparameter50UPR.

3Cylinder1-Cylinder2Two-layercircularpathscanningmeasurement,eachlayerwithatleast1270points,checkfilteringandoutlierrejection,low-passfilterparameter150UPR.RefertotheCOOKBOOK4DatumBSymmetryconstructedbetweenPlane1andPlane2.Usingthe"Symmetry"function.5Symmetry1SymmetryconstructedbetweenPlane3andPlane4.Usingthe"ConstructSymmetry"function.6Circle5 Usingthecentersofcircles1through4toformacircle. Usingthe"Call"function[TaskImplementation]VII.DefiningFeatures1.Definingthefeature"Ф37±0.05"Inthemenubar,click"Dimensions"→"Standards"→"Diameter".Underthe"Feature"tab,the"Diameter"iconwillappear.Double-clicktoopenthe"Diameter"dialogbox,anddefinethediameterfeatureasshowninthefigure.2.Definingthefeature"Coaxialityφ0.05(DatumA)"Inthemenubar,click"ShapeandLocation"→"Coaxiality".Underthe"Feature"tab,the"Coaxiality"iconwillappear.Double-clicktoopenthe"Coaxiality"dialogboxanddefinethe"Coaxialityφ0.05(DatumA)"featureasshowninthefigure.[TaskImplementation]VII.DefiningFeatures3.Definingthefeature"Ф42±0.02"Inthemenubar,click"Dimensions"→"Standards"→"Diameter".Underthe"Feature"tab,the"Diameter"iconwillappear.Double-clicktoopenthe"Diameter"dialogbox,anddefinethediameterfeatureasshowninthefigure.4.Definingthefeature"Ф80±0.1"Inthemenubar,click"Dimensions"→"Standards"→"Diameter".Underthe"Feature"tab,the"Diameter"iconwillappear.Double-clicktoopenthe"Diameter"dialogbox,anddefinethediameterfeatureasshowninthefigure.[TaskImplementation]VII.DefiningFeatures5.Definingthefeature"Symmetry0.05(DatumB)"Inthemenubar,click"ShapeandLocation"→"Symmetry".Underthe"Feature"tab,the"Symmetry"iconwillappear.Double-clicktoopenthe"Symmetry"dialogboxanddefinethe"Symmetry0.05(DatumB)"featureasshowninthefigure.[TaskImplementation]VIII.RunningtheProgramandDebuggingCheckthefivesafetyitemsandsetthesafetyparametersaccordingtothetablebelow.SerialNumberElementSafetyPlaneGroupSafetyDistanceRetractionDistance

ProbeMeasur