Ex.5-1 A plate cam with positive-offset translating roller follower is to have the following motion: a rise through lift h=40mm with a sine acceleration motion curve during 0=150, S=30, a return with a 3-4-5 polynomial motion curve during 0'=120, and S'=60. The cam rotates clockwise. The given dimensions are: rP=40mm. rR=12mm, e=12mm and rC=25mm. Construct the pitch curve and the cam contour graphically with a scale of 1:1. Label in red ink the centreline of the follower, S, the roller and the pressure angle corresponding to = 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+rr 4、偏置方向突变
5、曲线连接不光滑 6、不应沿径向减rr得实际廓线的点
Ex.5-2 A plate cam with translating offset roller follower has the same motion curve and dimensions as those in Ex.5-1. Write a program to calculate the co-ordinates of the pitch curve, the cam contour and the locus of the centre of the milling cutter, the pressure angle , and the radius B of curvature of the pitch curve.
Ex.5-3 For the plate cam with translating offset roller follower as shown below, arcs GH and IJ are two arcs with centre at O. Indicate the radius rP of prime circle, offset e, cam angle 0 for rise, cam angle S for outer dwell, cam angle 0' for return, cam angle S' for inner dwell and lift h. For the position shown, indicate pressure angle , displacement S and the corresponding cam angle .
Ex.5-3
根据实际廓线求理论廓线
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.
画基圆和偏置圆
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
升程开始处的导杆中心线并不过I点！！
画全等三角形
求0
求s
求0’
求S’
求h
S 和
Ex.5-3
典型错误： 1、不画出理论廓线 包义 张荣誉 何培昆 候金国 施健霞 王锦河 钟艺童 杨俊明
典型错误： 1、不画出理论廓线 2、偏置方向突变 3、圆心角等于推程角或回程角 陈中阳？赖龙笔？周小龙？钟艺童？杨俊明？廖乃祥?郑正洋？ 4、h=rmax-rmin
Ex.5-4 For the plate cam with translating offset roller follower as shown below, arcs EA, AB and BCD are three arcs with centre at O, N and P, respectively. Indicate the radius rP of prime circle, offset e, cam angle 0 for rise, cam angle S for outer dwell, cam angle 0' for return, cam angle S' for inner dwell and lift h. For the position shown, indicate pressure angle , displacement S and the corresponding cam angle .
Ex5-2
Ex.5-4
根据实际廓线求理论廓线
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.
画基圆和偏置圆
画升程开始处回程开始处和近休止开始处的导杆中心线
升程开始处的导杆中心线并不过A点！！ 画全等三角形
求0
求h
求0’
求S’
求S和
求
典型错误： 1、不画出理论廓线× 2、偏置方向突变× 3、h=rmax-rmin × 4、h不应包括S0 5、F应过N点 6、圆心角不应等于推程角或回程角 7、圆弧DCB不是用于远休止！
Ex.5-5 A plate cam with an oscillating roller follower similar to that in Fig.5-36 of textbook is to have the following motion: an angular lift MAX =20 with a sine acceleration motion curve during 0=150, S=30, a return with a 3-4-5 polynomial motion curve during 0'=120 and S'=60. The given dimensions are: rP=40mm, LOA=80mm, LAB=76mm, rR=12mm and rC=16mm. Construct the pitch curve and the cam contour graphically with a scale of 1:1. Label in red ink the frame OA, , centreline AB of the follower, the roller and corresponding to =60 and =0.
许多人将从动杆放在左侧？？？
Ex.5-6 A plate cam with an oscillating roller follower has the same motion curve and dimensions as those in Ex.5-5. Write a program to calculate the co-ordinates of the pitch curve, the cam contour and the locus of the centre of the milling cutter, the pressure angle and the radius B of curvature of the pitch curve.
Ex.5-7 For the plate cam with oscillating roller follower as shown below, arcs GH and IJ are two arcs with centre at O. Indicate radius of prime circle rP, cam angle for rise 0, cam angle for outer dwell S, cam angle for return 0', cam angle for inner dwell S' and angular lift MAX. For the position shown, indicate pressure angle , angular displacement of follower and the corresponding cam angle .
必须先画理论廓线！
O、H、H’三点共线。 O、I、I’三点共线。
Prime circle
Pivot circle
AHH’=AB AII’=AB AJJ’=AB AGG’=AB
AHOAI=0 HOI0
AIOAJ=S
AJOAG=0’ JOG 0’
AGOAH=S’
max OAI’max
and
Ex.5-8 A plate cam with a translating flat-faced follower is to have the following motion: a rise through lift h=50mm with a sine acceleration motion curve during 0=150, S=30, a return with a 3-4-5 polynomial motion curve during 0'=120 and S'=60. The cam rotates clockwise. The given dimensions are: rP=50mm. rC=20mm. Construct the pitch curve and the cam contour graphically with a scale of 1:1. Label in red ink the follower centreline, S, the flat face, the tangent point T between the cam contour and the flat face and corresponding to =60 and =0.
应该沿-方向作图！！
Ex.5-9 A plate cam with a translating flat-faced follower has the same motion curve and dimensions as those in Ex.5-8. Write a program to calculate the co-ordinates of the pitch curve, the cam contour and the locus of the centre of the milling cutter and the radius T of curvature of the cam contour.
补全运动规律
5-9 For the plate cam with translating offset roller follower as shown in Fig.5-33, arcs GH and IJ are two arcs with centre at O. Indicate rP, e, 0, S, 0', S', and h. For the position shown, indicate , S and the corresponding .
The required parameters cannot be found without the locus of the roller centre relative to the cam, or the pitch curve. The pitch curve and the cam contour are two parallel curves for the plate cam with roller follower. Draw offset circle and prime circle. Note: rp=OH’OH.
O、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。
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，
BB’=S.
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
5-16 For the plate cam with oscillating roller follower as shown in Fig.5-34, arcs GH and IJ are two arcs with centre at O. Indicate rP, 0, S, 0', S', and MAX. For the position shown, indicate i, i and the corresponding i.
The required parameters cannot be found without the locus of the roller centre relative to the cam, or the pitch curve. Draw prime circle and pivot circle. Note: rpOH.
O、H、H’三点共线。 O、I、I’三点共线。 O、J、J’三点共线。 O、G、G’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。
作A1H’=A2I’=A3J’=A4G’=AB, 得A1、A2、A3、和A4。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’。 相应地，A点从A1到A2、再到A3、再到A4、直至回到A1。
A1OA2=0, A2OA3=S, A3OA4=0’, A4OA1=S’, J”A3J’=max.
A1OA=, B’AB= . VAB.
5-19 For the plate cam with translating flat-faced follower as shown in Fig.5-35, arcs GH and IJ are two arcs with centre at O. Draw the pitch curve of the cam according to the given cam contour. Indicate rP, 0, S, 0', S' and h. For the position shown, indicate , S and the corresponding .