《机械原理（英汉双语）（第2版）》 课件Chapter 1--3 Introduction； Structural Analysis of Planar Mechanisms； Kinematic Analysis of Planar Mechanisms.pptx

TheoryofMachinesandMechanisms;Chapter1Introduction;1.TheConceptofMachinery;Fig.1-1Internalcombustionengineandscheme(内燃机及其机构简图)

1—piston(活塞)2—coupler(连杆)3—crankshaft(曲轴)4、5、6—gear(齿轮)7—cam(凸轮)

8—follower(推杆)9—lever(杠杆)10—valve(气门)11—frame(缸体);2.CompositionofMachines;Fig.1-3Automaticgate(电动大门示意图)

1—driver(驱动器)2—gate(大门)3—electromotor(电动机)4—reducer(减速器)

5—chaindriver(链传动)6—rollers(滚轮);Fig.1-4Constituteofthecoupler(连杆的组成)

1—bodyofthecoupler(连杆体)2—bearing(小端轴承)3—bearingbush(轴瓦)

4—headofthecoupler(连杆头)5—bolt(螺栓)6—nut(螺母)7—washer(垫圈);1.2TeachingContentandObjectoftheCourse;2.ContentofThisCourse;1.Purpose;2.Conclusion;Chapter2StructuralAnalysisofPlanarMechanisms;1.Link;2.KinematicPair;2)Slidingpair.Iftwolinkshaveaslidingmotionrelativetoeachother,theyformaslidingpairorprismaticpair.Fig.2-3showssomeslidingpairsandtheirsymbols.;(2)KinematicpairsaccordingtonatureofcontactAccordingtothefeatureofcontactbetweenthetwolinks,kinematicpairsmaybeclassifiedaslowerpairsandhigherpairs.;(3)KinematicpairelementThegeometricformsofcontactinapair,suchaspoint,lineorsurface,areknownaspairelements.

Apairismadeupoftwoelements,oneoneachlinkbeingjoined,suchastheoutsidecylindricalsurfaceofshaft1inFig.2-2andinnercylindricalsurfaceofbearing2inFig.2-2arepairelementsrespectively.。;3.KinematicChain;Fig.2-6Unclosedkinematicchains(开链);Fig.2-7Structures(桁架);Fig.2-8Mechanismsinwhichallthepairsarelowerpairs(低副机构);Fig.2-9Mechanismincludinghigherpair(高副机构);2.2SchematicDiagramofMechanisms;2.SymbolsofCommonUsedLinksandPairs;3.TheProcedureofDrawingaSchematicDiagramofaMechanism;(2)Theprocedureofdrawingaschematicdiagram

1)Findoutthedrivinglinksandthedrivenlinks.

2)Runthemechanismslowlyforawhile,thenstopitatasuitableposition,andobserveitsco