【20160406】Kinematic inversion" W7 B4 G: L' Q& H
运动倒置
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The cam will be imagined as being stationary.; B! A0 q" g* `( L- K6 C
The follower then should be rotated opposite to the direction of cam rotation.
# k/ G1 J1 a3 j# k6 a' p" @' fThe desired location for the follower, at several positions, is constructed from the base circle.
" T x8 O( U+ Z' ` `# }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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To creating the cam shape: wrapping the displacement diagram around the base circle.) |7 x3 h6 z- `4 k- C8 v, n
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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. j6 b: v6 g4 o3 j5 H. ^& d具体例子:
- ]9 R, U: ?9 m: I7 K① In-Line Knife-Edge Follower 对心直动尖顶从动件凸轮1 ?$ ?6 U$ L; \6 i7 W8 M
6 r$ \# R; L0 N, J8 Y# ?1. Draw the base circle of radius.
4 P$ O8 k) o1 `( X3 \2. Draw the follower in the home position./ G6 D& g+ D, ~9 d% E+ Y M
3. Draw radial lines from the center of the cam, corresponding to the cam angles identified on the displacement diagram.
+ e. g7 w; G! n9 n8 x$ m4. The follower will be rotated in a direction opposite to the actual cam rotation.: |& U1 A; d: w
5. Transfer the displacements from the displacement diagram to the radial lines.
5 g! u+ W/ T1 l" F2 Y8 _/ I, {& D6. Measure the displacements from the base circle.+ c2 |7 Y% \0 u( v7 |8 L6 N
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1.画出制定半径的基圆。
2 T" Q8 e; K: l" Z. s) s) S5 T2.画出初始位置的从动件。
" ^! Z( D$ N# _+ ^; c3.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。2 S3 m4 g. c9 f8 o5 p4 D9 z, h+ J
4.从动件与凸轮真实运动方向相反。
2 K( C- F i4 ~. O2 Z' ^$ K. o5.将位移移到径向线上。 g2 h+ A+ T! D: k
6.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1 S# _- `$ n$ M
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1. Draw the base circle of radius.
) D) [* \; Z0 p2 d2. Draw the follower centerline in the home position.
$ w9 L$ U6 [% B, X' t6 a; ?" |! q: ?3. Draw the prime circle.1 f& K6 |% a. g2 E6 X
4. Draw the follower in the home position of radius.
$ L7 Z( Y) N4 j8 n6 R9 t5. Draw an offset circle of radius, which will be tangent to the follower centerline.: {$ a3 l0 `; Q
6. Draw lines tangent to the offset circle, corresponding to the reference cam angles on the displacement diagram.; ?0 i. G( k8 O& y/ N5 P
7. The follower will be rotated in a direction opposite to the actual cam rotation.
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8 c5 `4 j& Z. F0 \8 ]1.画出制定半径的基圆。* I) Z% v A6 D( ?. s/ v2 A+ k2 k! p
2.画出初始位置的从动件中心线。
. w3 H7 H* J' H: X1 S" h$ i3.画出理论廓线。2 N& g- A4 Z8 P! h
4.画出初始位置的从动件。
1 @9 K* ~& i, C* h( s5.以偏心距为半径画圆,与从动件中心线相切。
' W8 M+ p" P x. _+ s6.与偏距圆相切画线,角度与位移图上横轴凸轮角度相对应。; Y8 w9 q+ s# C! K. U/ |4 m
7.从动件与凸轮真实运动方向相反。" A# N2 c$ V* X( @/ i
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