凸轮分析作业

Ex.5-1Aplatecamwithpositive-offsettranslatingrollerfolloweristohavethefollowingmotion:arisethroughlifth=40mmwithasineaccelerationmotioncurveduring0=150,S=30,areturnwitha3-4-5polynomialmotioncurveduring0'=120,andS'=60.Thecamrotatesclockwise.Thegivendimensionsare:rP=40mm.rR=12mm,e=12mmandrC=25mm.Constructthepitchcurveandthecamcontourgraphicallywithascaleof1:1.Labelinredinkthecentrelineofthefollower,S,therollerandthepressureanglecorrespondingto=60and=0.Ex.5-1典型错误：1、偏置方向错误2、不应沿方向作图3、基圆半径=rprp+rr4、偏置方向突变典型错误：5、曲线连接不光滑6、不应沿径向减rr得实际廓线的点Ex.5-2AplatecamwithtranslatingoffsetrollerfollowerhasthesamemotioncurveanddimensionsasthoseinEx.5-1.Writeaprogramtocalculatetheco-ordinatesofthepitchcurve,thecamcontourandthelocusofthecentreofthemillingcutter,thepressureangle,andtheradiusBofcurvatureofthepitchcurve.Ex.5-3Fortheplatecamwithtranslatingoffsetrollerfollowerasshownbelow,arcsGHandIJaretwoarcswithcentreatO.IndicatetheradiusrPofprimecircle,offsete,camangle0forrise,camangleSforouterdwell,camangle0'forreturn,camangleS'forinnerdwellandlifth.Forthepositionshown,indicatepressureangle,displacementSandthecorrespondingcamangle.Ex.5-3BIJOωGH根据实际廓线求理论廓线BOHGIJωIJHG''''擦掉实际廓线和滚子H’I’J’G’分别是升程开始处远休止开始处回程开始处和近休止开始处.BωIJHG''''IHGJO画基圆和偏置圆BOHGIJωIJHG''''e画升程开始处远休止开始处回程开始处和近休止开始处的导杆中心线BOHGIJωIJHG''''e画全等三角形BOHGIJωIJHG''''e求0BOHGIJωIJHG''''δ0e求sBOHGIJωIJHG''''δδ0se求0’BOHGIJωIJHG''''δδδ00s'e求S’BOHGIJωIJHG''''δδδδ00ss''e求hBOHGIJωIJHG''''δδδδ00ss''ehS和BOHGIJωIJHG''''δδδδ00ss''sδehEx.5-3BOHGIJωIJHG''''δδδδ00ss''sδehEx.5-4Fortheplatecamwithtranslatingoffsetrollerfollowerasshownbelow,arcsEA,ABandBCDarethreearcswithcentreatO,NandP,respectively.IndicatetheradiusrPofprimecircle,offsete,camangle0forrise,camangleSforouterdwell,camangle0'forreturn,camangleS'forinnerdwellandlifth.Forthepositionshown,indicatepressureangle,displacementSandthecorrespondingcamangle.Ex.5-4NEDAωOPBC根据实际廓线求理论廓线OPNABEC'ω'''AEBCD'D擦掉实际廓线和滚子H’I’J’G’分别是升程开始处远休止开始处回程开始处和近休止开始处.ABODCPNEABDEC'ω''''画基圆和偏置圆ABODCPNEABDEC'ω''''画升程开始处回程开始处和近休止开始处的导杆中心线OPNABEC'ω'''AEDCB'D画全等三角形ABODCPNEABDEC'ω''''M求0ABODCPNEABDEC'ωδ0''''M求hABODCPNEABDEC'ωδ0h''''M求0’ABODCPNEABDEC'ωδ0δ'0h''''M求S’ABODCPNEABDEC'ωδ0δ'0δs'h''''M求S和ABODCPNEABDECs'δωδ0δ'0δs'h''''M求ABODCPNEABDECs'δωδ0δ'0δs'h''''FVαMEx.5-5AplatecamwithanoscillatingrollerfollowersimilartothatinFig.5-36oftextbookistohavethefollowingmotion:anangularliftMAX=20withasineaccelerationmotioncurveduring0=150,S=30,areturnwitha3-4-5polynomialmotioncurveduring0'=120andS'=60.Thegivendimensionsare:rP=40mm,LOA=80mm,LAB=76mm,rR=12mmandrC=16mm.Constructthepitchcurveandthecamcontourgraphicallywithascaleof1:1.LabelinredinktheframeOA,,centrelineABofthefollower,therollerandcorrespondingto=60and=0.Ex.5-5Ex.5-6AplatecamwithanoscillatingrollerfollowerhasthesamemotioncurveanddimensionsasthoseinEx.5-5.Writeaprogramtocalculatetheco-ordinatesofthepitchcurve,thecamcontourandthelocusofthecentreofthemillingcutter,thepressureangleandtheradiusBofcurvatureofthepitchcurve.Ex.5-7Fortheplatecamwithoscillatingrollerfollowerasshownbelow,arcsGHandIJaretwoarcswithcentreatO.IndicateradiusofprimecirclerP,camangleforrise0,camangleforouterdwellS,camangleforreturn0',camangleforinnerdwellS'andangularliftMAX.Forthepositionshown,indicatepressureangle,angulardisplacementoffollowerandthecorrespondingcamangle.Ex.5-7Ex.5-7Ex.5-7Ex.5-7Ex.5-7Ex.5-7Ex.5-7Ex.5-7BOHGIJωsδ'0δsδ'δ'0HGJIAAAAHIJGBφmaxφδαFV''''Ex.5-7BOHGIJωsδ'0δsδ'δ'0HGJIAAAAHIJGBφmaxφδαFV''''Ex.5-8Aplatecamwithatranslatingflat-facedfolloweristohavethefollowingmotion:arisethroughlifth=50mmwithasineaccelerationmotioncurveduring0=150,S=30,areturnwitha3-4-5polynomialmotioncurveduring0'=120andS'=60.Thecamrotatesclockwise.Thegivendimensionsare:rP=50mm.rC=20mm.Constructthepitchcurveandthecamcontourgraphicallywithascaleof1:1.Labelinredinkthefollowercentreline,S,theflatface,thetangentpointTbetweenthecamcontourandtheflatfaceandcorrespondingto=60and=0.Ex.5-9Aplatecamwithatranslatingflat-facedfollowerhasthesamemotioncurveanddimensionsasthoseinEx.5-8.Writeaprogramtocalculatetheco-ordinatesofthepitchcurve,thecamcontourandthelocusofthecentreofthemillingcutterandtheradiusTofcurvatureofthecamcontour.补全运动规律ABCDhvaOOδδδABCDhvaOOδδδ5-9FortheplatecamwithtranslatingoffsetrollerfollowerasshowninFig.5-33,arcsGHandIJaretwoarcswithcentreatO.IndicaterP,e,0,S,0',S',andh.Forthepositionshown,indicate,Sandthecorresponding.BHGIJωOTherequiredparameterscannotbefoundwithoutthelocusoftherollercentrerelativetothecam,orthepitchcurve.Thepitchcurveandthecamcontouraretwoparallelcurvesfortheplatecamwithrollerfollower.Drawoffsetcircleandprimecircle.Note:rp=OH’OH.BHGIJωH'rpO、I、I’三点共线。O、J、J’三点共线。O、G、G’三点共线。O、H、H’三点共线。在理论廓线上，H’、I’、J’、G’分别对应于升程开始、升程结束、回程开始、回程结束。BHGIJωI'J'H'G'rp过H’、I’、J’、G’(不是过H、I、J、G)作偏置圆的切线。I’I”=hOI’-OH’.在反转过程中，滚子中心沿理论廓线从H’到I’、再到J’、再到G’、直至回到H’。BHGIJωI'J'H'G'oo''δsshrpδδδIoBHGIJωI'J'H'G'oo''δsshrpδδδIoBB’=S.BHGIJωI'J'H'G'hsαrpδI≈0V,FB'常见错误：不画理论廓线！圆心角当成推程角行程h沿径向线求偏置圆切线过实际廓线交接点改变偏置方向5-16Forthe