【菜鳥成長記】20歲后，我在機械的每一天

apmc111

加油，貴在堅持，希望你五年后還能來一篇總結

黑森林的鹿

apmc111 發表于 2016-3-28 21:05
加油，貴在堅持，希望你五年后還能來一篇總結

恩恩，會一直堅持下去的！感謝關注！

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swj1234

可以
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黑森林的鹿

【20160329】VelocityAnalysis
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0 H! Y! ~1 n; BVelocity analysis : determination of velocity in a linkage.
& [; Z# t2 ~# Y0 ^. s/ y速度分析：決定構件速度的分析。
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! _4 B& J" Q8 I7 ~Two common analysis methods：
( x% W  }2 @, H0 p% `Relative velocity method
Instantaneous center method
兩種常用方法：相對速度法和速度瞬心法。
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; n, I3 I3 [% Q3 u% rRelative velocity: the velocity of one object is related to that of another reference object, which can also be moving.
相對速度：兩個均運動的桿件之間相對的運動速度。
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VA = absolute velocity of point A
8 S. q' U" z3 ]1 a; B) S9 b, QVB/A= relative velocity of pointBwith respect to A
) @4 Q+ }2 L( h% V: z. [9 H相對速度的一些記法。
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1 a: `. O& ^! l, E) mInstant center: a instantaneous pivot point about which the particular link instantaneously appears to be in pure rotation.
速度瞬心：在運動的瞬時可看做是旋轉中心的點。

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黑森林的鹿

【20160330】Acceleration Analysis
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3 i/ L" H. N3 Q% _) P/ S6 m* hTangential acceleration 切向加速度
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. j0 [; G9 c8 Y, b1 s( e7 uNormal acceleration 法向加速度
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' _" S7 O4 Z* y$ x, ~, L' Y# MTotal acceleration 和加速度
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0 a8 `+ ~1 J: z! I! w3 \& ]Relative motion: the difference between the motion of two points.
相對運動：兩點運動的差（矢量）。
Relative acceleration: the acceleration of one object as observed from another reference object that is also moving.
3 a9 D* ]" r5 C2 ~# E相對加速度：一點相對于運動的另一點的加速度。
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& T1 ~; B. Y5 f3 }Coriolis Acceleration 科氏加速度

The magnitude of the Coriolis component:
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2 M6 [  z: t- [1 O  [Both the relative linear velocity and the absolute angular velocity can be determined from a thorough velocity analysis.
1 v5 F! f- c  S  H, [' p2 s計算科氏加速度的量可以從運動學分析中得到。
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黑森林的鹿

【20160331】Cams: Design and Kinematic Analysis



4 ~8 b5 Z# x5 R% {/ R5 P3 l" mThe camshaft is driven by the engine.
4 N3 j1 K1 F4 R. \% Q6 F3 eAs the cam rotates, a rocker arm drags on its oblong surface.
The rocker arm imparts a linear, reciprocating motion to a valve stem.
" |8 W( c) l% ^- R" ^The spring is used around the valve stem. The rocker arm follower needs to maintain contact with the cam surface to achieve the desired motion.
發動機中控制閥門進排氣的凸輪。應用彈簧使桿件與凸輪保持接觸。

The unique feature of a cam
  {/ B- A# ~. ^7 M1 U, |( c+ ]Cams 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.
凸輪的特點：凸輪可實現一般桿件不能或難于實現的功能。
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however1241

又來看樓主了，樓主還在更新著。

黑森林的鹿

【20160401】Type of Cams
0 h8 ]0 y9 T" z7 h$ r* [凸輪分類
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0 w" f, O1 t# p  Z4 K, VPlate or disk cams
This type of cam is formed on a disk or plate.
The radial distance from the center of the disk is varied.
平面凸輪：在平面內形成的凸輪，與中心的徑向距離是變化的。
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9 h5 q6 S3 p0 A; E/ A' z. `6 oCylindrical or drum cams
A groove is cut into the cylinder, with a varying location along the axis of rotation.
The follower is attached to the groove, thus giving the follower motion along the axis of rotation.
# K( Z8 P. w% _2 ~: n3 |, I) V圓柱凸輪：柱體上刻有凹槽，沿軸向變化分布，從動件被限制在凹槽內，因此沿軸向運動。
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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.
線凸輪：在板內刻有線型凹槽，從動件運動垂直于板的傳動方向。


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however1241

however1241 發表于 2016-4-1 18:18
又來看樓主了，樓主還在更新著。

老鷹版主會鼓勵吧。

劉星宇

同大二，啥專業基礎課都沒學，就搞機械創新，深深體會到無知，學起更有動力、更有興趣，還有，不帶手機去上課，就成功了一半，共勉