Speakers:ZhaoHui,YangGuoxingTianjinLightIndustryVocationalTechnicalCollegeDrawingtheThree-ViewProjectionofaConeConceptsofaConeandItsThree-ViewProjectionO1ONotetheprojectionoftheoutlineprofilelineandtheevaluationofthesurface’svisibility.SAAconeisasolidboundedby

aconicalsurfaceandacircularbase.ConesFormationoftheConicalSurfaceTheconicalsurfaceisformedbyrotatinglineSA(thegeneratrix)aboutitsintersectinglineOO1.ApexProfileLineThree-ViewProjectionoftheConeStepsforDrawingtheThree-ViewProjectionofaConeO1OSA

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SpecialPositionPointsSelectingPointsontheConicalSurfaceHowcanyouconstructastraightlineontheconicalsurface?Giventheprojections

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mPlaneCuttingaConeWhenthecuttingplaneisinclinedrelativetotheaxisθ>αEllipseCircleWhenthecuttingplaneisperpendiculartotheaxisθ=90°HyperbolaWhenthecuttingplaneisparalleltotheaxisθ=0°ParabolaWhenthecuttingplaneisparalleltooneprofilelineθ=αIsoscelestriangleWhenthecuttingplanepassesthroughtheapexWhatisthespatialshapeoftheintersectionline?Whatistheknownprojectionoftheintersectionline?Whatistherelationshipbetweenthecuttingplaneandthecone’saxis?★L(fēng)ocatethespecialpointsHowtolocatetheendpointsoftheotheraxisoftheellipse(i.e.,theforemostandrearmostpoints):★Addtheintermediatepoints.★Smoothlyconnectallpoints3.RefinetheOutline1.Analysis2.DeterminingtheIntersectionLine1'2'3‘(4’)5'(6')1"2"3"4"127‘(8')9‘(10')7"8"??5"6"??9"10"??78??910??43??56??AConeCutbyaVerticalPlane–CompletingtheThree-ViewProjectionPlaneCuttingaConeThree-viewprojectionandsoliddiagramofaconecutbyaverticalplane.1'2'3‘(4’)5'(6')7‘(8')9‘(10')