【菜鳥成長記】20歲后，我在機(jī)械的每一天

黑森林的鹿

【20160407】Pressure Angle
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It is the angle between the path of the follower motion and the line perpendicular to the cam profile at the point of contact.
; j+ B; f5 P! K9 w8 u0 I壓力角：從動(dòng)件運(yùn)動(dòng)軌跡與和凸輪輪廓接觸點(diǎn)垂直的線之間的夾角。

' F% N' H( a. W9 p& M7 I$ `Only one component of the contact force generates the follower motion.
7 w3 a1 i7 T+ Q* S接觸力的一個(gè)分力驅(qū)動(dòng)了從動(dòng)件的運(yùn)動(dòng)。
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In general:

! g% X9 `5 n) n; B2 [0 vThe magnitude of the pressure angle can be decreased by
1. Increasing the size of the base circle
2. Decreasing the magnitude of follower displacement
減小壓力角的方式：
3 P) \" N3 j' F; [1.增大基圓
3 v$ D# b# h% e4 J( @+ _. ?, O2.減小從動(dòng)件位移大小

黑森林的鹿

踏水行歌 發(fā)表于 2016-4-6 21:32
& c0 I$ K! I3 c% v: F+ i大四路過。。
% S9 Q, ~: [) T' J/ H" ~/ X6 p真是超級(jí)認(rèn)真的人啊>//////<
8 h6 y( u* w2 k; m+ p- b' h/ `' l樓主加油(•̀ロ•́)و✧ ~~

過獎(jiǎng)過獎(jiǎng)~謝謝鼓勵(lì)喲！↖(^ω^)↗

黑森林的鹿

劉星宇 發(fā)表于 2016-4-6 22:12
我還是踏上看帖的不歸路就好，你堅(jiān)持更，我慢慢看，會(huì)期待你每天更新的，加油！我們一起努力

恩呢！一定會(huì)堅(jiān)持下去的！

黑森林的鹿

小黑兔 發(fā)表于 2016-4-6 22:44
小妹紙 加油哦

! o! X( ]$ M8 g$ R謝謝鼓勵(lì)哈！注冊(cè)第一帖就是回我真是榮幸啊(⊙v⊙)
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黑森林的鹿

【20160408】Design Limitation

" j& u$ m% o% LAt a cam angle of 135°， there is a rapid rise and fall. The cam does not contact the follower, so the cam will not push the roller to the desired position.
+ {; R  k" I! q, b/ A7 J' a6 y& K1 ~在135°角處有位移的突變。凸輪無法接觸從動(dòng)件，因此凸輪將不會(huì)推動(dòng)滾輪作預(yù)設(shè)運(yùn)動(dòng)。
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' ]3 ^4 O5 y( t: \( F7 \* EThis situation can be corrected by：
解決方案：
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using a larger base circle；
reducing the diameter of the roller follower.
使用更大的基圓尺寸；
' J7 p; v$ o: m: V4 p& ]減小滾輪從動(dòng)件直徑。

+ N2 e: m. R. c4 }However, the contact stresses in the cam and follower are increased if the roller diameter is reduced.
9 v" B! O1 r2 w: Z但是若減小滾輪從動(dòng)件直徑，凸輪和從動(dòng)件的接觸應(yīng)力會(huì)相應(yīng)增大。
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黑森林的鹿

【20160409】Gears: Kinematic Analysis and Selection
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INTRODUCTION
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In general, the function of a gear is to transmit motion from one rotating shaft to another. In addition to transmitting the motion, gears are often used to increase or reduce speed, or change the direction of motion from one shaft to the other.
通常來說，齒輪的功能是在一個(gè)轉(zhuǎn)動(dòng)軸與另一個(gè)之間傳遞運(yùn)動(dòng)。除此之外，齒輪也常用于增速或降速，或者改變兩軸的運(yùn)動(dòng)方向。

. S9 `' T& L) b6 p) gFriction rollers or disks that are also designed to transmit motion are less costly than complex gear configurations， but they may not be able to generate sufficient frictional forces and thus will slip under larger loads. To remedy the possibility of slipping, a gear is formed such that the smooth surfaces of the disks are replaced by teeth. The teeth provide a positive engagement and eliminate slipping.
盡管摩擦輪也可傳遞運(yùn)動(dòng)，而且比復(fù)雜的齒輪配置更加經(jīng)濟(jì)，但可能因摩擦力不足而導(dǎo)致打滑。為彌補(bǔ)這一缺陷，帶齒齒輪取代摩擦輪成為了主流。帶齒齒輪嚙合更好，并能減少打滑現(xiàn)象。
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TYPES OF GEARS
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Spur gears are simplest and, hence, the most common type of gear. The teeth of a spur gear are parallel to the axis of rotation. Spur gears are used to transmit motion between parallel shafts, which encompasses the majority of applications. A pair of mating spur gears is illustrated in Figure 10.3a.
# t* g+ U, ^2 K7 O! Q直齒輪最簡單，應(yīng)用也最廣。直齒輪的齒與轉(zhuǎn)動(dòng)軸平行（指邊）。直齒輪用于傳遞兩平行軸之間的運(yùn)動(dòng)，這占了實(shí)際生產(chǎn)中的大多數(shù)情況。圖a為一對(duì)配合的直齒輪。

A rack is a special case of spur gear where the teeth of the rack are not formed around a circle, but laid flat. The rack can be perceived as a spur gear with an infinitely large diameter.When the rack mates with a spur gear, translating motion is produced. A mating rack and gear are illustrated in Figure 10.3b.
齒條是直齒輪的特例，齒條的齒不是繞圓，而是平鋪形成的。齒條可以看做是無限直徑的圓。齒輪和齒條配合時(shí)產(chǎn)生平移運(yùn)動(dòng)。圖b為一對(duì)配合的齒輪齒條。
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) ^: C& w8 d4 G' r! B9 ~/ Y, k6 EInternal or annular gears have the teeth formed on the inner surface of a circle. When mating with a spur gear, the internal gear has the advantage of reducing the distance between the gear centers for a given speed variation. An internal gear mating with a traditional spur gear is illustrated in Figure 10.3c.
% Q" k  ^3 c) J, H  l內(nèi)齒輪的齒在圓的內(nèi)表面形成。與直齒輪嚙合時(shí)，在給定的速度下，內(nèi)齒輪能有效減少兩齒輪中心的距離。圖c為內(nèi)齒輪與普通直齒輪配合。

Helical gears are similar to, and can be used in the same applications as, spur gears. The difference is that the teeth of a helical gear are inclined to the axis of rotation. The angle of inclination is termed the helix angle, . This angle provides a more gradual engagement of the teeth during meshing and produces less impact and noise. Because of this smoother action, helical gears are preferred in high-speed applications. However, the helix angle produces thrust forces and bending couples, which are not generated in spur gears. A pair of mating helical gears is illustrated in Figure 10.3d.
斜齒輪與直齒輪有很多類似之處，不同的是它的齒與轉(zhuǎn)軸有一定夾角，稱為螺旋角。螺旋角使配合更平穩(wěn)，產(chǎn)生的壓力和噪音也更小。因此高速場合多用斜齒輪。然而螺旋角會(huì)產(chǎn)生軸向力與彎曲偶，直齒輪卻不會(huì)產(chǎn)生。圖d為喻隊(duì)配合的斜齒輪。
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$ R( Q) p) Y- `( SHerringbone gears are used in the same applications as spur gears and helical gears. In fact, they are also referred to as double helical gears. The herringbone gear appears as two opposite-hand helical gears butted against each other. This complex configuration counterbalances the thrust force of a helical gear. A herringbone gear is shown in Figure 10.3e.
人字齒的用途與直齒輪、斜齒輪類似。實(shí)際上也把它叫做雙斜齒輪。人字齒有兩個(gè)相反方向的螺線。這種復(fù)雜的配置平衡了螺旋角的軸向力。圖e為人字齒。
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Bevel gears have teeth formed on a conical surface and are used to transmit motion between nonparallel shafts. Although most of their applications involve connecting perpendicular shafts, bevel gears can also be used in applications that require shaft angles that are both larger and smaller than 90°. As bevel gears mesh, their cones have a common apex. However, the actual cone angle of each gear depends on the gear ratio of the mating gears. Therefore, bevel gears are designed as a set, and replacing one gear to alter the gear ratio is not possible. A pair of mating bevel gears is illustrated in Figure 10.3f.
圓錐齒輪的齒在圓錐表面上形成。用于傳遞不平行軸之間的運(yùn)動(dòng)。大多數(shù)情況下圓錐齒輪用于傳遞垂直軸間的運(yùn)動(dòng)，但也可傳遞成任意角度的軸之間的運(yùn)動(dòng)。圓錐齒輪配合時(shí)錐頂重合。然而錐角決定于齒數(shù)比。因此圓錐齒輪一般成套設(shè)計(jì)，通過改變一個(gè)齒輪來改變齒數(shù)比是不現(xiàn)實(shí)的。圖f是一對(duì)配合的圓錐齒輪。

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% W6 A8 p/ U* X  oMiter gears are a special case of bevel gears where the gears are of equal size and the shaft angle is 90°. A pair of mating miter gears is illustrated in Figure 10.3g.
等齒數(shù)整角錐齒輪副是圓錐齒輪的特例，兩齒輪有相同的尺寸，并且兩軸成90°。圖g為一對(duì)配合的等齒數(shù)整角錐齒輪副。

A worm and worm gear is used to transmit motion between nonparallel and nonintersecting shafts. The worm has one tooth that is formed in a spiral around a pitch cylinder. This one tooth is also referred to as the thread because it resembles a screw thread. Similar to the helical gear, the spiral pitch of the worm generates an axial force that must be supported. In most applications, the worm drives the worm gear to produce great speed reductions. Generally, a worm gear drive is not reversible. That is, the worm gear cannot drive the worm. A mating worm and worm gear are shown in Figure 10.3h.
蝸輪蝸桿用于傳遞不平行不相交軸之間的運(yùn)動(dòng)。蝸桿是指具有一個(gè)或幾個(gè)螺旋齒，并且與蝸輪嚙合而組成交錯(cuò)軸齒輪副的齒輪。這一螺旋齒也被稱作螺紋。與斜齒輪類似，蝸桿的螺線產(chǎn)生軸向力。絕大多數(shù)情況下，由蝸桿驅(qū)動(dòng)渦輪產(chǎn)生巨大的減速。一般來說渦輪驅(qū)動(dòng)是不可逆的，也就是說，渦輪不能驅(qū)動(dòng)蝸桿。圖h為一對(duì)配合的蝸輪蝸桿。

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劉星宇

黑森林的鹿 發(fā)表于 2016-4-9 17:26
【20160409】Gears: Kinematic Analysis and Selection
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2 m6 L3 x+ s% M& T9 qINTRODUCTION

看英語真累，by the way，樓主自己翻譯的么
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黑森林的鹿

【20160410】Spur Gear Terminology
5 N. G3 ?; N# _! _( X) M直齒輪相關(guān)術(shù)語

Pitch circle: the circle that represents the size of the corresponding friction roller that could replace the gear.
4 d0 D8 S4 ]) S2 q  h' F- {2 n2 o分度圓：代表對(duì)應(yīng)摩擦輪尺寸的圓。
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Pitch point: the point of contact of the two pitch circles.
齒輪嚙合節(jié)點(diǎn)：兩個(gè)分度圓的接觸點(diǎn)。

Pitch diameter: the diameter of the pitch circle, also a widely referenced gear parameter.
節(jié)徑：分度圓的直徑。也普遍被叫做齒輪直徑。

3 j) n$ V# Q: u! I9 }Number of teeth(N): the total number of teeth on the gear.
齒數(shù)：齒輪上的總齒數(shù)。

4 a: j3 ?8 B5 }0 e1 }) dCircular pitch(p): the distance measured along the pitch circle from a point on one tooth to the corresponding point on the adjacent tooth of the gear.
3 Y, ?; u4 f2 j9 f齒距：分度圓上一齒到臨近另一齒對(duì)應(yīng)位置的距離。
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0 K  r) C/ Q  ]3 a! Z; SBase circle : the circle from which the curved shape of the gear tooth is constructed.
基圓：齒輪的齒從其上形成的圓。

Face width(F): the length of the gear tooth parallel with the shaft axis.
0 v/ e' F  o, {& o* p齒寬：齒輪齒的實(shí)體在軸向上的長度。
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* `8 F, Y1 M; |! f) N) AAddendum(a): the radial distance from the pitch circle to the top of a gear tooth.
齒頂高：分度圓到齒頂?shù)膹较蚓嚯x。

Dedendum(b): the radial distance from the pitch circle to the bottom of a gear tooth.
3 j$ P$ [8 T$ [( v齒根高：分度圓到齒根的徑向距離。
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8 k$ I0 R$ W+ r8 f  iWhole depth: the height of a gear tooth and is the sum of the addendum and dedendum.
總寬：齒的高度，也就是齒頂高與齒根高之和。
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Diametral pitch(Pd): the number of teeth per inch of pitch diameter; a standard for tooth size specifications.
2 c9 Q& F! c9 a( K* B1 I1 d  d徑節(jié)：節(jié)徑上每英寸的齒數(shù)；作為齒輪大小的選擇標(biāo)準(zhǔn)。
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Module(m): a relative measure of tooth size. It is defined as the ratio of pitch diameter to the number of teeth in a gear.
3 ~6 F/ }4 Z& V; x5 }模數(shù)：齒大小的衡量標(biāo)準(zhǔn)。定義是徑節(jié)與齒數(shù)之比。
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Pressure angle(ϕ): angle between the pitch line and the pressure line.
- |2 y( @4 j2 C# o3 B8 g5 kBecause the pressure angle affects the shape of a tooth, two mating gears must have the same pressure angle.
壓力角：節(jié)線與壓力線間的夾角。影響齒輪形狀，因此配合的齒輪必須有同樣的壓力角。

0 A/ g- H6 a* z: J& B5 gPitch line: the line tangent to the pitch circles.
節(jié)線：與分度圓相切的線。
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( }7 O( H* _  d0 c7 MPressure line: the line perpendicular to the surfaces of the teeth at the contact.
% x- z1 d% Z( ~6 \+ l! ~壓力線：與齒接觸面垂直的線。
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黑森林的鹿

劉星宇 發(fā)表于 2016-4-9 23:13
看英語真累，by the way，樓主自己翻譯的么

$ u4 w3 e7 V: H9 ?6 I哈哈，多看就好~是自己翻譯呀，如有不當(dāng)歡迎指出~

黑森林的鹿

【20160411】Fundamental law of gearing
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' k5 O9 l' \2 R  H; s  t; r8 {Fundamental law of gearing：the angular velocity ratio between the gears of a gearset remains constant throughout the mesh.
齒廓嚙合基本定律：嚙合過程中兩齒輪的角速度之比保持不變。
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! t: e8 O0 h, f4 C6 X4 eP: instant center.
/ p0 w9 m* A$ q6 n0 XP點(diǎn)為速度瞬心。
. q7 X& p1 H8 @  q9 C' EVelocity ratio:
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* [6 [1 K, m* nConstant velocity ratio：point P should be fixed.
速度比恒定的意義：P點(diǎn)固定。
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