【20160406】Kinematic inversion
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The cam will be imagined as being stationary.& d) F; u+ L8 K% T" \8 N7 @
The follower then should be rotated opposite to the direction of cam rotation.
/ Q/ i" u( ?- E; B; w! P n% fThe desired location for the follower, at several positions, is constructed from the base circle.( h: ?+ W7 d/ u7 n
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。, s# p9 k+ N4 y. @( r, @
: Y+ B% V: J' p( i1 H4 d8 fTo creating the cam shape: wrapping the displacement diagram around the base circle.7 p2 ]$ b$ k8 Q* F& c4 e
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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* G0 I! D: k. a$ y1 @ ~$ H具体例子:
7 Z' ?6 A6 Y: N( ^7 {① In-Line Knife-Edge Follower 对心直动尖顶从动件凸轮
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9 H1 ], y" x, \! A5 q1. Draw the base circle of radius.
9 {! T& C3 R# I, s; P" p6 ^2. Draw the follower in the home position.
+ t6 Q- Q( O6 p! H5 [. C3 ^3. Draw radial lines from the center of the cam, corresponding to the cam angles identified on the displacement diagram.
. `5 b' U7 ?4 R; z) U& d+ ]/ J4. The follower will be rotated in a direction opposite to the actual cam rotation.3 I' @" o- y% M3 v/ ?! [' ~$ n2 Z
5. Transfer the displacements from the displacement diagram to the radial lines.
" y$ X! m; T3 I6. Measure the displacements from the base circle.
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! {0 C, D3 [7 K' \! r( T1.画出制定半径的基圆。
: f& @* j% K- S8 ]2.画出初始位置的从动件。* x8 m1 f9 J4 f$ T: m) r9 @6 Q* Q) K
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。5 y$ X/ b: f+ p1 {1 x) C/ A& i
4.从动件与凸轮真实运动方向相反。! x" T$ }5 l3 l7 `
5.将位移移到径向线上。
* D- B6 e: k% y( s$ ?* _* a6.测量从动件远离凸轮基圆的距离。4 R) D( a7 v' R( T
7 V2 g' i) W; t( c/ m② Offset Roller Follower 偏置滚轮从动件+ f( L# [: L6 g$ l& q, z) k
/ p) S5 v1 `) V3 p" M" y! q1. Draw the base circle of radius.& d! Q7 H) q2 z. V( W- l* u; e
2. Draw the follower centerline in the home position.
- c+ `* c' D, r' o3. Draw the prime circle., J/ g( [9 c5 k" E% `& k3 W
4. Draw the follower in the home position of radius.4 H, z/ K# s) w }9 y, H
5. Draw an offset circle of radius, which will be tangent to the follower centerline.
: t/ T5 t5 z; l6. Draw lines tangent to the offset circle, corresponding to the reference cam angles on the displacement diagram.& B4 ~1 B! @- ?' n( |' [4 H
7. The follower will be rotated in a direction opposite to the actual cam rotation.- c3 e0 v( G. \( f9 f1 i3 t
& \/ O9 k8 u1 E5 ~1.画出制定半径的基圆。$ P% m) v8 Z6 T/ [7 P% J2 M: g
2.画出初始位置的从动件中心线。& h1 }3 B4 C, b4 B, T+ ?
3.画出理论廓线。9 X) E" j; K( o8 R, l9 Q; F
4.画出初始位置的从动件。6 B( h' F, h7 S/ R
5.以偏心距为半径画圆,与从动件中心线相切。
$ z3 Y- Q5 s: F: @. W# x( Q* y+ x6.与偏距圆相切画线,角度与位移图上横轴凸轮角度相对应。4 d; |1 j/ f' \
7.从动件与凸轮真实运动方向相反。8 F- R& m: w: [4 Q* i
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