【菜鳥(niǎo)成長(zhǎng)記】20歲后，我在機(jī)械的每一天

apmc111

加油，貴在堅(jiān)持，希望你五年后還能來(lái)一篇總結(jié)

黑森林的鹿

apmc111 發(fā)表于 2016-3-28 21:05
加油，貴在堅(jiān)持，希望你五年后還能來(lái)一篇總結(jié)

0 z: h6 o$ e6 A( \* u. D6 p恩恩，會(huì)一直堅(jiān)持下去的！感謝關(guān)注！

swj1234

可以

黑森林的鹿

【20160329】VelocityAnalysis

Velocity analysis : determination of velocity in a linkage.
速度分析：決定構(gòu)件速度的分析。
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$ |  a! |: k$ X& r0 J- jTwo common analysis methods：
Relative velocity method
Instantaneous center method
兩種常用方法：相對(duì)速度法和速度瞬心法。

Relative velocity: the velocity of one object is related to that of another reference object, which can also be moving.
3 ]2 |6 C% y. k, K" [相對(duì)速度：兩個(gè)均運(yùn)動(dòng)的桿件之間相對(duì)的運(yùn)動(dòng)速度。

VA = absolute velocity of point A
VB/A= relative velocity of pointBwith respect to A
" q' t! t! L! R) [9 ~, o: |# P相對(duì)速度的一些記法。
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8 w8 `/ s) V7 W, \; SInstant center: a instantaneous pivot point about which the particular link instantaneously appears to be in pure rotation.
速度瞬心：在運(yùn)動(dòng)的瞬時(shí)可看做是旋轉(zhuǎn)中心的點(diǎn)。

黑森林的鹿

【20160330】Acceleration Analysis

Tangential acceleration 切向加速度

Normal acceleration 法向加速度
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% e) n5 L* \3 hTotal acceleration 和加速度

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3 U# k- e( C+ M" w# [Relative motion: the difference between the motion of two points.
相對(duì)運(yùn)動(dòng)：兩點(diǎn)運(yùn)動(dòng)的差（矢量）。
Relative acceleration: the acceleration of one object as observed from another reference object that is also moving.
- W% n/ c* u* v9 c$ V相對(duì)加速度：一點(diǎn)相對(duì)于運(yùn)動(dòng)的另一點(diǎn)的加速度。
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! i' X9 Y6 \/ E* l3 Q  GCoriolis Acceleration 科氏加速度
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5 \; S+ Z3 q3 e  F8 D  ^The magnitude of the Coriolis component:

  S1 Y% @" E4 pBoth the relative linear velocity and the absolute angular velocity can be determined from a thorough velocity analysis.
: K- z: _' Z5 T( D& Z3 O' y計(jì)算科氏加速度的量可以從運(yùn)動(dòng)學(xué)分析中得到。
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黑森林的鹿

【20160331】Cams: Design and Kinematic Analysis


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& {6 L3 }; P- \' i/ rThe camshaft is driven by the engine.
As the cam rotates, a rocker arm drags on its oblong surface.
7 v9 B" P8 E: y; y% }The rocker arm imparts a linear, reciprocating motion to a valve stem.
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(fā)動(dòng)機(jī)中控制閥門(mén)進(jìn)排氣的凸輪。應(yīng)用彈簧使桿件與凸輪保持接觸。
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5 r# U/ H( Z2 ?The unique feature of a cam
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.
0 E# P7 {, J2 C% ], M9 S. n0 h5 w$ p! [凸輪的特點(diǎn)：凸輪可實(shí)現(xiàn)一般桿件不能或難于實(shí)現(xiàn)的功能。

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however1241

又來(lái)看樓主了，樓主還在更新著。

黑森林的鹿

【20160401】Type of Cams
9 }' q: ~2 n2 F& ?* y! @2 W凸輪分類(lèi)
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Plate or disk cams
This type of cam is formed on a disk or plate.
; X4 l0 Q* _& w: RThe radial distance from the center of the disk is varied.
平面凸輪：在平面內(nèi)形成的凸輪，與中心的徑向距離是變化的。

9 p, W/ S6 p3 L3 A7 L1 P& e* v$ bCylindrical or drum cams
2 p% M- t7 S' u  L& m) A  UA groove is cut into the cylinder, with a varying location along the axis of rotation.
6 P2 a/ S; c6 [5 zThe follower is attached to the groove, thus giving the follower motion along the axis of rotation.
& E9 K. z  R% a0 }. H1 k圓柱凸輪：柱體上刻有凹槽，沿軸向變化分布，從動(dòng)件被限制在凹槽內(nèi)，因此沿軸向運(yùn)動(dòng)。
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Linear cam
. [& l9 k1 ^/ r+ p7 a1 c" g9 aA 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.
  P9 N# H6 ~9 Y  v: \# _# h9 j$ p線凸輪：在板內(nèi)刻有線型凹槽，從動(dòng)件運(yùn)動(dòng)垂直于板的傳動(dòng)方向。

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however1241

however1241 發(fā)表于 2016-4-1 18:18
又來(lái)看樓主了，樓主還在更新著。

老鷹版主會(huì)鼓勵(lì)吧。
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劉星宇

同大二，啥專(zhuān)業(yè)基礎(chǔ)課都沒(méi)學(xué)，就搞機(jī)械創(chuàng)新，深深體會(huì)到無(wú)知，學(xué)起更有動(dòng)力、更有興趣，還有，不帶手機(jī)去上課，就成功了一半，共勉