【菜鸟成长记】20岁后，我在机械的每一天

apmc111

加油，贵在坚持，希望你五年后还能来一篇总结

黑森林的鹿

apmc111 发表于 2016-3-28 21:05
加油，贵在坚持，希望你五年后还能来一篇总结

恩恩，会一直坚持下去的！感谢关注！
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swj1234

可以
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黑森林的鹿

【20160329】VelocityAnalysis

! [( Y, Y) c2 {% `Velocity analysis : determination of velocity in a linkage.
. W6 _# G9 h2 _: ?+ C5 o1 e速度分析：决定构件速度的分析。
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/ q% U6 x! y9 Y) @, p. K, b4 [Two common analysis methods：
Relative velocity method
6 ?. K( A# _% V# n: G+ o  f. B% qInstantaneous center method
" b# h8 `5 X$ t2 r+ m两种常用方法：相对速度法和速度瞬心法。

. q$ f$ B; ?- u; }, g: o) Z6 ARelative velocity: the velocity of one object is related to that of another reference object, which can also be moving.
4 z5 Q# x+ q6 Q. j2 v- s相对速度：两个均运动的杆件之间相对的运动速度。
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VA = absolute velocity of point A
VB/A= relative velocity of pointBwith respect to A
" x3 f, V( k! C3 o8 N( @- s- {相对速度的一些记法。

" }. I2 L) `, V  M* o' w% rInstant center: a instantaneous pivot point about which the particular link instantaneously appears to be in pure rotation.
; ], j2 Q: S0 I. `速度瞬心：在运动的瞬时可看做是旋转中心的点。
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黑森林的鹿

【20160330】Acceleration Analysis
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Tangential acceleration 切向加速度
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Normal acceleration 法向加速度

Total acceleration 和加速度


) E! S/ L  R' j$ `9 {) D9 }Relative motion: the difference between the motion of two points.
9 p2 S; x# p3 ]# R* N' G相对运动：两点运动的差（矢量）。
; L2 N( g* Z2 vRelative acceleration: the acceleration of one object as observed from another reference object that is also moving.
2 W3 d( d2 j5 O# A6 y+ }相对加速度：一点相对于运动的另一点的加速度。
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Coriolis Acceleration 科氏加速度

+ f- _& d% |/ b( B+ D: B% wThe magnitude of the Coriolis component:

Both the relative linear velocity and the absolute angular velocity can be determined from a thorough velocity analysis.
计算科氏加速度的量可以从运动学分析中得到。
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黑森林的鹿

【20160331】Cams: Design and Kinematic Analysis

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; C7 P, t7 c  D! `) dThe camshaft is driven by the engine.
As the cam rotates, a rocker arm drags on its oblong surface.
The rocker arm imparts a linear, reciprocating motion to a valve stem.
/ a1 W0 ]# \7 E4 KThe spring is used around the valve stem. The rocker arm follower needs to maintain contact with the cam surface to achieve the desired motion.
6 ]8 k8 g! K/ s) w. L发动机中控制阀门进排气的凸轮。应用弹簧使杆件与凸轮保持接触。

5 X$ G6 t' O- X4 Q9 |The unique feature of a cam
( y% G1 ~3 E; H9 Z' o+ ]/ w2 ACams can be used to obtain unusual or irregular motion that would be difficult or impossible, to obtain from other linkages, because the motion of cams can be prescribed.
凸轮的特点：凸轮可实现一般杆件不能或难于实现的功能。
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however1241

又来看楼主了，楼主还在更新着。

黑森林的鹿

【20160401】Type of Cams
( ~+ t/ Q3 F& ^凸轮分类

Plate or disk cams
This type of cam is formed on a disk or plate.
& e5 x% X( u$ W, R6 `, F( g2 {- ?The radial distance from the center of the disk is varied.
0 ]' ~0 l  l4 I: @* I平面凸轮：在平面内形成的凸轮，与中心的径向距离是变化的。

# a. {0 p! Z7 XCylindrical or drum cams
A groove is cut into the cylinder, with a varying location along the axis of rotation.
0 `, O( M! g1 R0 J. a5 }The follower is attached to the groove, thus giving the follower motion along the axis of rotation.
圆柱凸轮：柱体上刻有凹槽，沿轴向变化分布，从动件被限制在凹槽内，因此沿轴向运动。
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; S0 ~8 B' i) m+ }Linear cam
A groove is cut into the block with a distance that varies from the plane of translation.
Attaching a follower in the groove gives the follower motion perpendicular to the plane of translation.
线凸轮：在板内刻有线型凹槽，从动件运动垂直于板的传动方向。
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however1241

however1241 发表于 2016-4-1 18:18
又来看楼主了，楼主还在更新着。

老鹰版主会鼓励吧。
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刘星宇

同大二，啥专业基础课都没学，就搞机械创新，深深体会到无知，学起更有动力、更有兴趣，还有，不带手机去上课，就成功了一半，共勉