【20160406】Kinematic inversion
% Y8 ^& I5 h) w5 z" m运动倒置1 P/ X( a5 Q0 B2 W. K8 _
8 c4 r. b# k3 g2 `9 m7 R5 c: sThe cam will be imagined as being stationary.
; b4 G6 v. i2 y' Q Y9 aThe follower then should be rotated opposite to the direction of cam rotation.0 Q x: H% }- j0 `' d6 V' E
The desired location for the follower, at several positions, is constructed from the base circle.& w8 a; s, @3 I) q
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。5 c- j+ A/ b3 N. c8 l
4 _, e) s7 J$ e2 B4 g# ~8 DTo creating the cam shape: wrapping the displacement diagram around the base circle.( O# f' q" i1 @8 J
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。4 ~" \ U) A1 |
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具体例子:
& Q& @$ h; H* @9 E( I+ l9 j① In-Line Knife-Edge Follower 对心直动尖顶从动件凸轮
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1. Draw the base circle of radius.
* T# K0 D: E! I5 N4 @1 c2. Draw the follower in the home position.
; Z3 N) r2 I' i @" R1 u, U6 n1 G3. Draw radial lines from the center of the cam, corresponding to the cam angles identified on the displacement diagram.
# R9 G1 }) |. `4. The follower will be rotated in a direction opposite to the actual cam rotation.
" k: Q5 E u( c4 Y5. Transfer the displacements from the displacement diagram to the radial lines.. w/ J- |0 u3 K7 N
6. Measure the displacements from the base circle.+ t; P0 B* @/ H4 {% t" e w. d
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1.画出制定半径的基圆。' O& |0 b! @( r2 s! T
2.画出初始位置的从动件。) e. W2 e; e5 V [1 l) ?
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。
$ i3 x) A( n: A% {# y- a4 M( I7 T4.从动件与凸轮真实运动方向相反。
; S1 w2 @6 ^" Y( v* C6 }6 B$ N5.将位移移到径向线上。
& ~+ ?3 E, d `4 C: B t9 A6.测量从动件远离凸轮基圆的距离。
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② Offset Roller Follower 偏置滚轮从动件
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" F' x3 m) F, ~9 B0 M% I7 R1 K1. Draw the base circle of radius.. T2 T" b# u/ C5 A* T P9 N M
2. Draw the follower centerline in the home position.
, d: r6 ^+ M9 ^" F3. Draw the prime circle.
# h/ b* o8 l6 |- k' I$ F$ _4. Draw the follower in the home position of radius.
" V/ O7 F9 u. ^; W: ~/ ]$ ?5. Draw an offset circle of radius, which will be tangent to the follower centerline.
3 K- i1 u$ U, G8 o5 }! e& @- E6. Draw lines tangent to the offset circle, corresponding to the reference cam angles on the displacement diagram.
& k; ?3 Y: Y2 O7. The follower will be rotated in a direction opposite to the actual cam rotation.6 F; @% A" T7 D9 ]8 L! v
/ a* p1 k& a% P9 ^* K, d1.画出制定半径的基圆。4 E. q# p( p* z2 p6 S! e+ e
2.画出初始位置的从动件中心线。4 I. Z& V' ~2 U5 }* J; b9 I' ^ C6 E
3.画出理论廓线。7 [) |" v1 G5 p' S
4.画出初始位置的从动件。
6 F; l; Y' i; @: R5.以偏心距为半径画圆,与从动件中心线相切。
$ ]1 G) O) q# R/ _6.与偏距圆相切画线,角度与位移图上横轴凸轮角度相对应。. B# [$ P4 v: c* i/ r5 A9 A+ N
7.从动件与凸轮真实运动方向相反。4 R. l$ Z" g+ H7 d
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