【20160406】Kinematic inversion# T- G- f8 k( @& X1 {
运动倒置
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The cam will be imagined as being stationary.
2 R5 ?2 q- _! l* Z& N; @8 qThe follower then should be rotated opposite to the direction of cam rotation.( b! [+ @: u5 ~6 E
The desired location for the follower, at several positions, is constructed from the base circle.
( Q) r* l3 m, p) m; S. g: a" a, `. G假定凸轮不动,从动件沿相反方向转动,在基圆上画出从动件的几个预期运动位置。
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8 Y$ A8 g$ [9 D% f( j: J) [9 eTo creating the cam shape: wrapping the displacement diagram around the base circle.
& c$ y) ]! J7 [% ?# P! C设计凸轮形状时,用从动件位移图上的位移将基圆“包裹”起来。
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) G3 @- v4 ?+ Y; U0 v. f具体例子:
' M( H& u1 t! m' k6 e( V① In-Line Knife-Edge Follower 对心直动尖顶从动件凸轮
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) }0 E( J3 y% t3 J- k" `1. Draw the base circle of radius.
0 @! J% g. p. e/ `$ b# A% h" R2. Draw the follower in the home position.
; O8 V& D2 l, V0 q* h. w/ a% T3. Draw radial lines from the center of the cam, corresponding to the cam angles identified on the displacement diagram.
+ H7 x( X% U W4. The follower will be rotated in a direction opposite to the actual cam rotation.; W, b b/ O" _4 ?3 ?+ n
5. Transfer the displacements from the displacement diagram to the radial lines.
b I" d; P* b+ U9 ~5 _6. Measure the displacements from the base circle.# u( `; Z1 y' y. i$ z) F9 _) V: Q
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1.画出制定半径的基圆。
! C7 J# F, q2 h5 M3 @2.画出初始位置的从动件。- _3 \' F1 ?* u$ F$ b t8 n
3.从中心画出基圆的径向线,角度与位移图上横轴凸轮角度相对应。
& F; A& z# J$ J' t4.从动件与凸轮真实运动方向相反。" @4 h$ ~+ ~2 ?, H) N
5.将位移移到径向线上。
" w% p: f% z0 \, g: I. e6.测量从动件远离凸轮基圆的距离。% A, K/ d& {1 V5 U
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② Offset Roller Follower 偏置滚轮从动件 M( i1 @: B( h- [9 ~; I8 u9 }
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1. Draw the base circle of radius.
4 T, k% M; X- R# B2. Draw the follower centerline in the home position.
& R7 L p+ ^+ _, I! V0 o3. Draw the prime circle.' h. J7 h/ a2 R. f; S% {: w
4. Draw the follower in the home position of radius.5 t; d( G4 h6 `$ D- l- K3 F
5. Draw an offset circle of radius, which will be tangent to the follower centerline.
7 ^) @4 u" Y) N9 r0 \6. Draw lines tangent to the offset circle, corresponding to the reference cam angles on the displacement diagram.) \3 k" X# H+ A
7. The follower will be rotated in a direction opposite to the actual cam rotation.
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' B' P. b4 z# q8 N$ v6 G1.画出制定半径的基圆。
. ^/ X# X: M5 r' f- e8 n. F2.画出初始位置的从动件中心线。
3 {6 Y, J$ k- g5 Q3.画出理论廓线。
, `( h* q7 N5 a2 ?) N4.画出初始位置的从动件。
$ H# ^7 m! I5 A# H5.以偏心距为半径画圆,与从动件中心线相切。
9 B5 d2 V3 I: n9 `' R5 }7 c% D! D6.与偏距圆相切画线,角度与位移图上横轴凸轮角度相对应。: p/ B0 U) v7 k! Y, y
7.从动件与凸轮真实运动方向相反。
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