外文翻譯--鏈輪的制造方法

1、<p>　　Gear manufacturing methods</p><p><b>　　Abstract</b></p><p>　　This paper deals with the production process of the chain wheel. It Detailed description of gear planning

2、 ,gear shaping, gear hobbing, gear broaching , gear shaving ,gear grinding, and introduce the teeth of the production of a variety of methods and the used occasions.</p><p>　　Key Words </p><p>　

3、　gear planning ,gear shaping, gear hobbing, gear broaching , gear shaving ,gear grinding,</p><p>　　Gear Planing the shape of the space between gear teeth is complex and varies with the number of the gear

4、as well as tooth module, so most gear manufacturing methods generate the tooth flank instead of forming .</p><p>　　Gear planing uses a reciprocating racks, stroking in the direction of the helix on agear wi

5、th a gradual generation of from as the rack effectively rolls round the gear blank . The rack is relieved out of contact for the return stroke as in normal shaping or planning .It has the great advantage that the cutting

6、 tools is a sampling rack with (nearing) straight sided teeth which can easily be ground accurately .This method is little used for high production because it is relatively slow in operatio</p><p>　　Gear sha

7、ping gear shaping is inherently similar to gear planning but uses a circular cutter instead of a rack and the resulting reduction in the reciprocating inertia allows much higher stroking speed ;modern gear shapers cutti

8、ng car gears can run at 2000 cutting strokes per minute .The shape of the cutter is roughly the same as an involute gear but the tips of the teeth are rounded .</p><p>　　The generating drive between cutter

9、and workpiece does not involve a rack or leadscrew since only circular motion is involve a rack or leadscrew since only circular motion is involved . The tool and workpiece move tangentially typically 0.5 mm for each str

10、oke of the cutter .on the return stroke the cutter must be retracted about 1mm to give clearance otherwise tool rub occurs on the backstroke and failure is rapid.</p><p>　　The advantage of gear shaping are

11、that production rates are relatively high and that is the possible to cut right up to a shoulder .Unfortunately , for helical gears ,a helical guide is required to impose a rotational motion on the stroking motion ;such

12、helical guides cannot be produced easily or cheaply so the method is only suitable for long runs with helical gears since special cutter and guides must be manufactured for each each different helix angle .a great advant

13、age of gear shaping is its</p><p>　　Gear Hobbing gear hobbing , the most used metal cutting method , uses the rack generating principle but avoids slow reciprocation by mounting mangy “racks” on a rotating

14、 cutter .the “racks” are displaced axially to from a gashed worm.</p><p>　　Metal removal rates are high since no reciprocation of hob or workpiece is required and so cutting speeds 40 m/min can be used for c

15、onventional hobs and up to 150m/min for carbide hobs . Typically with a 100mm diameter hob the rotation speed will be 100rpm and so a twenty tooth workpiece will rotate at 5 rpm. Each revolution of the workpiece will cor

16、respond to 0.75mm feed so the hob will advance through the workpiece at about 4mm per minute .for car production roughing multiple start hobs can be</p><p>　　Gear Broaching Gear broaching is not usually used

17、 for helical gears but is used for internal sour gears ;the principle used of broaching in the context is for internal splines which cannot easily de made by any other method .As with all broaching the method is only eco

18、nomic for large quantities since setup costs are high .</p><p>　　Gear broaching give high accuracy and low surface roughness but like all cutting processes is limited to “soft ” materials which must be subse

19、quently case-hardened or haet treated ,giving distortion .</p><p>　　Gear Shaving Gear shaving is used as finishing processes for gears in the “soft ” state .The objective is to improve surface roughness and

20、profile by mating the roughed-out gear with a “cutter” which will improve form .</p><p>　　A gear shaving cutter looks like a gear which has extra clearance at the root (for swarf and coolant removal) and who

21、se tooth flanks have been grooved to give cutting edges. It is run mesh with the rough gear with crossed axes so that there is in theory point contact with a relative velocity along the teeth giving scraping action .The

22、gear shaving cutter tooth are relatively flexible in bending and so will only operate effectively when they are in double contact between two gear teeth. The gear </p><p>　　Gear Grinding Gear grinding is ext

23、remely important because it is the main way hardened gears are machined .when high accuracy is required it is not sufficient to pre-correct for heat treatment distortion and grinding is then necessary .</p><p&

24、gt;　　The simplest approach to gear is form grinding .The wheel profit is dressed accurately to shape required using single point diamonds which are controlled by templates cut to the exact shape required .The profiled wh

25、eel is then reciprocated axially along the gear, when one tooth shape has been finished ,involving typically 100 micron metal removal ,the gear is indexed to the next tooth space . This method is fairly slow but gives hi

26、gh accuracy consistently .Setting up is lengthy because different</p><p>　　The fastest gear grinding method used the principle as gear hobbing but replace a gashed and relived by a grinding wheel which is a

27、rack in section. Only single start worm are cut on the wheel but gear rotation speeds are high, 100 rpm typically, so it is difficult to design the drive system to give accuracy and rigidity .</p><p>　　Accur

28、acy of the process is reasonably high although there is a tendency for wheel and workpiece to deflect variably during grinding so the wheel from may required compensation for machine deflection effectes .Generation of a

29、worm shape on the grinding wheel is a slow process since a dressing diamond must not only form the rack profile but has to move axially as the wheel rotates. Once the wheel has been trued, gears can be ground rapidly unt

30、il redressing is required. This is the most popular met</p><p><b>　　鏈輪的制造方法</b></p><p>　　摘要 ：這篇文章主要介紹了鏈輪的制造過程，詳細(xì)地?cái)⑹隽伺冽X，插齒，滾齒，拉齒，剃齒，磨齒；并且詳細(xì)地介紹了各種制作方法的利弊和運(yùn)用場(chǎng)合。</p><p>　　關(guān)鍵

31、詞 ：刨齒，插齒，滾齒，拉齒，剃齒，磨齒</p><p>　　鏈輪齒間的空間形狀是復(fù)雜的,而且隨著齒輪的齒數(shù)和模數(shù)的不用而變化，因此大多數(shù)的鏈輪制造方法采用戰(zhàn)成尺郭而不是成形加工。</p><p>　　刨齒是采用往復(fù)運(yùn)動(dòng)的齒條刀，當(dāng)齒條刀繞鏈輪胚料滾切并延其螺旋線方向運(yùn)動(dòng)時(shí)，齒形就會(huì)被逐漸展成。與普通的刨削加工相同，在回程中齒條刀與齒輪脫離接觸。這種加工方法最大的好處是，刀具為具有直線齒形

32、或者接近于直線齒形的齒條，其齒面易于進(jìn)行精確加工。由于刀具和滑枕的質(zhì)量較大，造成了加工速度和緩慢，因此這種方法幾乎不在大批量的加工中應(yīng)用。對(duì)于單件或者少量的齒輪加工而言，緩慢的行程速度帶來的影響不大，而且較低的刀具成本對(duì)于那些特殊規(guī)格和需要進(jìn)行齒廓修行的齒輪來說則是一個(gè)有利條件。</p><p>　　插齒，插齒加工在本質(zhì)上和刨齒加工相類似，只是采用圓形刀具來代替齒條刀。其結(jié)果是減少了往復(fù)運(yùn)動(dòng)的慣性，在加工過程中可

33、以采用比刨削高得多的速度。現(xiàn)代插齒機(jī)在加工汽車齒輪時(shí)可以達(dá)到每分鐘2000次切削行程。插齒刀的形狀與漸開齒輪大致相同，但是其齒頂是圓的。</p><p>　　由于刀具與工件之間的展成傳動(dòng)只包含圓周運(yùn)動(dòng)，因此不需要齒條或絲杠。在刀具的每一次行程中，通常刀具和工件的切向移動(dòng)距為0.5mm，在回程中，刀具必須退讓1mm以留出間隙。否則，再退刀時(shí)，刀具會(huì)擦傷以加工表面，并且加快刀具的磨損。</p><

34、p>　　插齒加工的優(yōu)點(diǎn)是生產(chǎn)率較高和可以將吃插到接近軸肩處。令人遺憾的是，加工斜齒輪時(shí)，需要一個(gè)能夠產(chǎn)生繞插齒運(yùn)動(dòng)行程本身旋轉(zhuǎn)的螺旋導(dǎo)軌。這種螺旋導(dǎo)軌不易制造，或者說其制造成本較高。由于對(duì)每一種不同螺旋角的齒輪，應(yīng)該制造不同參數(shù)的插齒刀，因此這種方法只適合斜齒輪的大批量加工。插齒加工的一大優(yōu)點(diǎn)是能夠加工諸如大型行星齒輪傳動(dòng)所需的內(nèi)齒輪。</p><p>　　滾齒，滾齒是最常見的金屬切削方法。它采用齒條展成原

35、理，但是通過安裝在旋轉(zhuǎn)刀上的“齒條”來避免緩慢的往復(fù)運(yùn)動(dòng)。這些“齒條”軸向排布，形成了有縫的蝸桿。</p><p>　　由于滾刀和工件均不做往復(fù)運(yùn)動(dòng)，因此滾齒加工時(shí)的金屬切削率很高。對(duì)于普通滾刀可以采取40m/min 的切削速度，對(duì)于硬質(zhì)合金滾刀可采用高達(dá)150m/min的切削速度。一般采用直徑為100mm的滾刀，其轉(zhuǎn)速為100r/min，一個(gè)20個(gè)齒的齒輪將以5r/min的切削速度旋轉(zhuǎn)。工件的每一轉(zhuǎn)將有0.75

36、mm的進(jìn)給量，因此滾刀每分鐘要對(duì)工件進(jìn)給4mm。在汽車制造中，采用多頭粗加工滾刀，達(dá)到每轉(zhuǎn)3mm的大進(jìn)給量。這樣當(dāng)?shù)毒叩霓D(zhuǎn)速為100r/min時(shí)，采用雙頭滾刀加工齒數(shù)為20的齒輪，其進(jìn)給量達(dá)到30mm/min.</p><p>　　拉齒通常不采用拉削的方法加工斜齒輪，但是在直齒輪加工中拉削是適用的。在這種情況下，拉削主要被用來加工其他任何一種方法都不易加工的內(nèi)花鍵。同所有的拉削加工一樣，因?yàn)樵O(shè)備的費(fèi)用很高，齒輪拉

37、削方法只有在大批量生產(chǎn)時(shí)才是經(jīng)濟(jì)的。</p><p>　　通過拉齒可以獲得高精度和低表面粗糙度。但是如同所有的切削加工一樣，拉削也只能用來加工“軟”材料。隨后應(yīng)該對(duì)材料進(jìn)行表面硬化或熱處理，而這會(huì)產(chǎn)生變形。</p><p>　　剃齒 ，采用剃齒方式可以對(duì)處于“軟”狀態(tài)的齒輪進(jìn)行精加工。其目的是通過采用具有提高齒形精度能力的“刀具”與通過粗加工的齒輪進(jìn)行嚙合來降低齒面粗糙度和改善齒廓形狀。&

38、lt;/p><p>　　剃齒刀形狀如齒輪，在刀齒的根部有一附加的凹槽（用于排出切屑和冷卻液），在齒面上開有許多小槽一形成切削刃。剃齒刀與經(jīng)過加工的齒輪成交錯(cuò)軸嚙合傳動(dòng)。這樣在理論上沿著輪齒有一個(gè)具有相對(duì)速度的點(diǎn)接觸，從而產(chǎn)生刮削作用。剃齒刀的刀齒具有相當(dāng)?shù)膹澢嵝?，因此只有?dāng)它們?cè)趦蓚€(gè)輪齒之間并且與這兩個(gè)輪齒都接觸時(shí)，才能有效地進(jìn)行切削工作。在齒輪和刀具高速旋轉(zhuǎn)的同時(shí)沿齒面橫向進(jìn)給，大約可以切除0.1mm的材料。切削

39、周期可能小于半分鐘，機(jī)床的價(jià)格也不昂貴，但是刀具比較精密，難于制造。</p><p>　　磨齒，磨齒是非常重要的，因?yàn)樗羌庸ご阌昌X輪的主要方法。當(dāng)對(duì)于熱處理變形的預(yù)先校正達(dá)不到齒輪所要求的高精度時(shí)，就必須采用磨削加工。</p><p>　　最簡(jiǎn)單的磨削方法是成形磨削法。采用有精密切削成形的樣板控制的單刃金剛石可以將砂輪修正成精確的形狀。成形砂輪沿著齒輪軸向進(jìn)給。在一個(gè)輪齒的形狀加工完成以

40、后，通常要除去0.1mm的金屬。當(dāng)然，齒輪將會(huì)被分度到下一個(gè)輪齒空間。這種方法的加工速度相當(dāng)慢，但是在整個(gè)加工過程中都可以獲得較高的精度。對(duì)于不同的模數(shù),齒數(shù)，螺旋角或者齒廓修行量，需要采用不同的砂輪修正樣板，因此就需要有較長(zhǎng)的安裝調(diào)整時(shí)間。</p><p>　　最快的磨削方法采用與滾齒相同的原理，但是使用截面為齒條的砂輪來取代鈾排屑槽的蝸桿形滾齒刀。砂輪只能被切削成單頭蝸桿形，由于鏈輪的轉(zhuǎn)速通常高達(dá)100r/m