【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
' v& r5 K( p; |( ^加油，贵在坚持，希望你五年后还能来一篇总结

6 u& ~# A8 |7 R. t恩恩，会一直坚持下去的！感谢关注！
; ^- M8 \9 o/ e" E( f8 T

swj1234

可以
) N. ^. L+ X2 t" L0 A: y

黑森林的鹿

【20160329】VelocityAnalysis
* K  p" Q1 |* N  w
1 s( \/ Y# [# q7 Q7 {* IVelocity analysis : determination of velocity in a linkage.
速度分析：决定构件速度的分析。
' ~: F0 H6 o/ J. K5 D1 o
Two common analysis methods：
, _5 p. `/ A0 i' H0 DRelative velocity method
Instantaneous center method
两种常用方法：相对速度法和速度瞬心法。

7 W7 n+ c9 I2 zRelative velocity: the velocity of one object is related to that of another reference object, which can also be moving.
% f3 R7 J, J% x! ~& U相对速度：两个均运动的杆件之间相对的运动速度。
% @& Y: Q( K: ]7 [6 _, P% p
VA = absolute velocity of point A
VB/A= relative velocity of pointBwith respect to A
相对速度的一些记法。
5 R1 ]4 f+ u( ~/ V7 g  g; I
* D8 Y7 m" Z/ H; D$ p# z: @( _$ bInstant center: a instantaneous pivot point about which the particular link instantaneously appears to be in pure rotation.
( o$ {+ E% A8 M; R- X( G速度瞬心：在运动的瞬时可看做是旋转中心的点。

* q0 T+ F, S" M

黑森林的鹿

【20160330】Acceleration Analysis
6 n- T. D% N: c9 H
0 E5 q' g% `8 m+ X  [! vTangential acceleration 切向加速度

Normal acceleration 法向加速度
: f$ M  F% N) J$ c( d0 s
0 H- ^5 [; s: CTotal acceleration 和加速度
! M, n8 r9 P; z
; O5 k+ f: f, D" c) j8 x5 _
Relative motion: the difference between the motion of two points.
0 H5 ]% H6 X2 n相对运动：两点运动的差（矢量）。
0 E* b& j! L" Y+ D% F5 |Relative acceleration: the acceleration of one object as observed from another reference object that is also moving.
相对加速度：一点相对于运动的另一点的加速度。

/ W1 E' p( A0 f' YCoriolis Acceleration 科氏加速度
4 f3 Z# W9 \1 f% u' f4 w+ w$ a, y  m
' z3 Q, @2 b0 }! ?, x0 _The magnitude of the Coriolis component:

Both the relative linear velocity and the absolute angular velocity can be determined from a thorough velocity analysis.
7 f7 m% B5 r, K4 `* ^, Q3 ?计算科氏加速度的量可以从运动学分析中得到。
/ r* H( c( _! q* Z) z

黑森林的鹿

【20160331】Cams: Design and Kinematic Analysis

! y6 M5 }% }9 f9 Y2 T

0 R3 L: z4 t% t) y/ sThe camshaft is driven by the engine.
As the cam rotates, a rocker arm drags on its oblong surface.
5 Y) _. r0 }: i; CThe 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.
9 Y3 `5 Y9 x* `% u) m& g7 q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。
3 r- L7 F& k! s# R
3 }- g6 r+ e2 N4 `5 Y$ _The unique feature of a cam
( `7 q( h) i/ r% @' ZCams 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.
8 I$ T( a; _8 c1 |# u0 @凸轮的特点：凸轮可实现一般杆件不能或难于实现的功能。
% p4 S: A+ @9 ?
9 W2 i2 I, y4 u8 _3 U

however1241

又来看楼主了，楼主还在更新着。

黑森林的鹿

【20160401】Type of Cams
0 L5 ]9 p  m% h  u6 ?凸轮分类
7 l6 f& ?: S4 }2 T; p
  F+ d; v( p' KPlate or disk cams
This type of cam is formed on a disk or plate.
+ @) z2 J! z9 z( ^5 M" |+ P" nThe radial distance from the center of the disk is varied.
. t0 O. c+ e$ m! r! M2 R# p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。

) V& q5 d( [% bCylindrical or drum cams
, t2 A0 s) G* b1 E8 @9 XA 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.
& ~6 r9 \$ h' e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。

# |6 l7 Q) B5 p0 ZLinear cam
% e1 U( z. I9 AA groove is cut into the block with a distance that varies from the plane of translation.
2 e' v/ ?( h# Y, _# KAttaching a follower in the groove gives the follower motion perpendicular to the plane of translation.
) N0 h. G- `: ?8 f# X. K8 j. |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。
: B4 \( J) p9 e/ o

: r" A' ^7 o7 R

however1241

however1241 发表于 2016-4-1 18:18
4 M  e* {# T; u. e1 L& D' o又来看楼主了，楼主还在更新着。

老鹰版主会鼓励吧。
6 r$ \3 H2 f9 s5 N* K2 V' j

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