L-17SurftestPerforms brilliantly in many situations such as in the quality control room, on the factory oor and on the production line. Mitutoyo reserves the right to change any or all aspects of any product specication, including prices, designs and service content, without notice.L-17Surftest (Surface Roughness Testers)Quick Guide to Precision Measuring InstrumentsISO 4287: 1997 Geometrical Product Specications (GPS) –Surface Texture: Prole method– Terms, denitions, and surface texture parametersISO 4288: 1996 Geometrical Product Specications (GPS) –Surface Texture: Prole method– Rules and procedures for the assessment of surface textureISO 3274: 1996 Geometrical Product Specications (GPS) –Surface Texture: Prole method– Nominal characteristics of contact (stylus) instrumentsISO 11562: 1996 Geometrical Product Specications (GPS) –Surface texture: Prole method– Metrological characteristics of phase correct ltersFeed deviceColumnProbe (pickup)ProbeStylus (contact element)WorkpieceFixtureBaseMeasuring loopTransducerTracedproleStylus tipReferenceproleReferenceguide skidNominalform removalPrimaryproleADconverterProle lter λSAnalysis according to ISO 4287AmplierFeeddeviceSurfaceMeasure-mentloopExternaldisturbancesDrive UnitZ-axis Signal Transfer UnitInput/OutputInput/OutputTotal proleA prole lter is a phase-correct lter without phase delay (cause of prole distortion dependent on wavelength).The weight function of a phase-correct lter shows a normal (Gaussian) distribution in which the amplitude transmission is 50 % at the cutoff wavelength.Elements of Contact Type Surface Roughness Measuring Instruments Data Processing FlowSurface ProlesMetrological Characterization of Phase Correct FiltersSurface proleon the real surfaceTracedproleTotalprolePrimary prolePrimary proleparametersRoughness proleWaviness proleRoughnessprole parametersWavinessprole parametersLow-pass lterof cutoff value λsHigh-pass lter of cutoff value λcBand-pass lter that passes wavelengthsbetween cutoff values λc and λfMeasurementAD conversionSuppresses irrelevant geometry of the surface such as inclination of a at feature and curvature of a cylindrical feature using the least squares method.Denition: Prole that results from the intersection of the real surface and a plane rectangular to it.Denition: Locus of the center of the stylus tip that traces the workpiece surface.Denition: Data obtained by quantizing the traced prole.ISO 3274: 1996 (JIS B 0651: 2001)ISO 11562: 1996(JIS B 0632: 2001)(JIS B 0651)60°60°60°90°90°90°R2 µmR5 µmR10 µmR2 µmR5 µmR10 µmStylus ShapeA typical shape for a stylus end is conical with a spherical tip.Tip radius: rtip = 2 µm, 5 µm or 10 µmCone angle: 60°, 90°In typical surface roughness testers, the conical angle of the stylus end is 60˚ unless otherwise specied.Static Measuring ForceNote 1: The maximum value of static measuring force at the average position of a stylus is to be 4.0 mN for a special structured probe including a replaceable stylus.Nominal radius ofcurvature of stylus tip:µmStatic measuring force atthe mean position ofstylus: mNTolerance on staticmeasuring forcevariations: mN/µm25100.75 0.75 (4.0) Note 10.0350.2 Maximum sampling lengthµmλcmmλsµmλc/λsRelationship between Cutoff Value and Stylus Tip RadiusThe following table lists the relationship between the roughness prole cutoff value λc, stylus tip radius rtip, and cutoff ratio λc/λs.Note 1: For a surface with Ra>0.5 µm or Rz>3 µm, a signicant error will not usually occur in a measurement even if rtip = 5 µm.Note 2: If a cutoff value λs is 2.5 µm or 8 µm, attenuation of the signal due to the mechanical ltering effect of a stylus with the recommended tip radius appears outside the roughness prole pass band. Therefore, a small error in stylus tip radius or shape does not affect parameter values calculated from measurements. If a specic cutoff ratio is required, the ratio must be dened.Maximum rtipµmNote 1 Note 2 Note 2 0.08 0.25 0.8 2.5 8 2.5 2.5 2.5 8 25 0.5 0.5 0.5 1.5 5 30 100 300 300 300 2 2 2 5 10ISO 4287:199750100λsλcλfAmplitude Transmission %WavelengthRoughness proleWaviness prolePrimary ProleProle obtained from the measured prole by applying a low-pass lter with cutoff value λs.Roughness ProleProle obtained from the primary prole by suppressing the longer wavelength components using a high-pass lter of cutoff value λc.Waviness ProleProle obtained by applying a band-pass lter to the primary prole to remove the longer wavelengths above λf and the shorter wavelengths below λc.Primary proleRoughness sampling length for non-periodic prolesISO 4288: 1996 (JIS B 0633: 2001)Procedure for determining a sampling length if it is not speciedEstimate Ra, Rz, Rz1max., or RSm accordingto recorded waveforms, visual inspection, etc.NoNoNoYesYesYesHas a shorter sampling length been tried?Fig.1 Procedure for determining the sampling length of an aperiodic prole if it is not specied.Does the measuredvalue meet the conditionof Table 3?Change the samplinglength so as to meet the condition of Table 3Fig.2 Procedure for determining the sampling length of a periodic prole if it is not specied.Estimate the sampling length from anestimated value and Tables 1 to 3Estimate RSm froma measured roughness proleEstimate the sampling length froman estimated value and Table 3Measure the parameter accordingto the nal sampling lengthMeasure RSm according to the estimatedvalue of the sampling lengthMeasure Ra, Rz, Rz1max., or RSm according tothe estimated value of the sampling lengthMeasure the parameter accordingto the nal sampling lengthChange to a shortersampling lengthChange to a longeror shorter samplinglengthDoes each measuredvalue meet the parameter rangeof Table 1, 2, or 3?Table 1: Sampling lengths for aperiodic prole roughness parameters (Ra, Rq, Rsk, Rku, RΔq), material ratio curve, probability density function, and related parametersTable 2: Sampling lengths for aperiodic prole roughness parameters (Rz, Rv, Rp, Rc, Rt)Table 3: Sampling lengths for measurement of periodic roughness prole roughness parameters and periodic or aperiodic prole parameter Rsm1) Rz is used for measurement of Rz, Rv, Rp, Rc, and Rt.2) Rz1max. only used for measurement of Rz1max., Rv1max., Rp1max., and Rc1max..Sampling length lrmm0.µm(0.025)

元のページ  ../index.html#548