【菜鳥成長記】20歲后，我在機械的每一天

の小南灬

看看，加油

zqphho999

也想進步。

黑森林的鹿

【20160412】Involute Tooth Profile
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An involute shape is constructed by unwinding a taut wire from a base circle with diameter db.
漸開線由直徑為db的基圓上解開一條拉線形成。
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“Taut wire” is always tangent to base circle and normal to involute.
: I! a8 J1 s$ `7 }: P8 x/ S7 }: o“拉線”總與基圓相切，垂直于漸開線。
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The center of curvature of the involute is always at the point of tangency of the “taut wire” with the base circle.
" B. m* W6 S9 C* ^  N' K曲率中心總在基圓與拉線切點處。
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Any portion of tooth profile inside the base circle is not an involute.
基圓以內無漸開線。

Involute profile provide the constant velocity ratio.
漸開線能保證速度比恒定。


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黑森林的鹿

の小南灬 發表于 2016-4-11 21:18
看看，加油

恩吶~
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黑森林的鹿

zqphho999 發表于 2016-4-12 19:50
也想進步。

3 \: q3 T! {+ D4 s4 i- W, H8 C7 O# z共同進步！

黑森林的鹿

【20160413】Standard Gears
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Any two involute gears with the same diametral pitch and pressure angle will mate.
徑節和壓力角相同的漸開線齒輪可以配合。

Gear teeth have been standardized based on the diametral pitch and pressure. Standard pressure angles are
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齒輪的齒以徑節和壓力為基準進行標準化。標準壓力角如圖。

The standardized values of diametral pitch：
標準徑節值如下表：


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The manufacturers must follow a standard convention to form the details of the gear tooth profile. The AGMA is the primary organization that oversees this standardization scheme.
齒輪齒廓的加工必須遵循一定規則，美國齒輪制造協會首先制定相關規定。

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黑森林的鹿

【20160414】Relationships of Gears in Mesh

5 h7 h# T$ W' }9 c5 \% hCenter Distance
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Pinion-the smaller gear  小齒輪
Bull gear or gear -the larger gear  大齒輪

Contact ratio( mp ): the average number of teeth that are in contact at any instant.
( b4 a8 U: j4 b$ Q, k% [重合度：任意時刻相互接觸的齒數。
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- m+ o+ D5 y' W; b) p' {0 V; A1 Fwhere
Z -The length of the contact path( length of straight line）
0 {! ^+ x3 X6 q6 q! Vpb-The base pitch, which is defined as the distance between corresponding points of adjacent teeth, measured on the base circle( length of arc )
1 O" \( N/ s) @  K6 C; {6 Q/ i  m4 L嚙合度=接觸長度（直線長度）/節距（弧線長度）
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An involute shape is constructed by unwinding a taut wire from a base circle.
" n3 m2 Y% X" k6 H8 E% }. o漸開線的形成方式決定了直線段KN與弧線段AN的長度相等。
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Inpractice, contact ratios should be greater than 1.2.
# R8 D9 U3 U# D/ F$ P實際應用中，重合度應大于1.2。
A contact ratio of 1.2 indicates that one pair of teeth is always in contact and a second pair of teeth is incontact 20 percent of the time.
重合度為1.2意味著，一對齒總是接觸，第二對齒有20%的時間接觸。

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黑森林的鹿

【20160415】Interference

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dedendum circle > base circle

/ y' U  }. J" I" x- @dedendum circle < base circle
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Gear teeth have involute profiles between the base circle and the addendum circle. When a gear with few teeth and small pressure angles is constructed, the dedendum circle is considerably smaller than the base circle of the involute. Therefore, the tooth between the base circle and the dedendum is not an involute.
( ~0 h1 O  ^% `' O) [' k基圓與齒頂高間的齒具有漸開線齒廓。當齒輪的齒數過少并且壓力角很小時，齒根高遠小于形成漸開線的基圓。因此，基圓與齒根高間的齒不是漸開線齒輪。
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0 ]  ?+ Y) `' Y: E) L' vInterference：If the mating gear tooth were to contact the non-involute portion of the tooth, the fundamental condition for constant velocity ratio would be violated.
( ?. F0 A# x( t* a干涉：配合的齒輪在非漸開線處接觸時，常速定理不滿足。
* w+ C2 Y$ p1 C. |8 |' rdrastic noise, vibration, and wear 不利：噪音，速度突變，磨損

# g1 L) K4 |! w0 t" u, aTo avoid interference，the maximum number of gear teeth is given as
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為避免干涉，最大齒數應滿足如上公式。
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cwyyyy

20歲 與題主共勉

垨護伱の噯

樓主好強大  加油   我比樓主大好多但是沒你條件好 幼兒園畢業 然后再家放牛到15歲 15歲半近機械廠摸爬滾打數十載，現在26了 工資5000塊 礦山設備行業，期間做個，鏜，銑  車，焊接，鑄造 鍛造，完全 自學 唯一花錢學的東西就是UG數控還沒學會 制圖會了  從原材料做到現在的整機，，好艱辛 ，哎看看你們都是大學生，想想我的前途都蛋疼 都不敢跟你們說我還有夢想了