外文翻譯--齒輪和軸的介紹

1、<p>　　畢業(yè)設(shè)計(jì)(論文)外文資料翻譯</p><p>　　系　　部： 機(jī)械工程系 </p><p>　　專 業(yè)： 機(jī)械工程及自動化 </p><p>　　姓 名： </p><p>　　學(xué)

2、 號： </p><p>　　外文出處： 《Manufacturing Engineering and </p><p>　　Technology—Machining》 </p>

3、<p>　　附 件： 1.外文資料翻譯譯文；2.外文原文。 </p><p>　　注：請將該封面與附件裝訂成冊。</p><p>　　附件1：外文資料翻譯譯文</p><p><b>　　齒輪和軸的介紹</b></p><p>　　摘　要:在傳統(tǒng)機(jī)械和現(xiàn)代機(jī)械中齒輪和軸的重要地位是不可動搖的。齒輪和軸主

4、要安裝在主軸箱來傳遞力的方向。通過加工制造它們可以分為許多的型號，分別用于許多的場合。所以我們對齒輪和軸的了解和認(rèn)識必須是多層次多方位的。</p><p><b>　　關(guān)鍵詞:齒輪；軸</b></p><p>　　在直齒圓柱齒輪的受力分析中，是假定各力作用在單一平面的。我們將研究作用力具有三維坐標(biāo)的齒輪。因此，在斜齒輪的情況下，其齒向是不平行于回轉(zhuǎn)軸線的。而在錐齒輪的

5、情況中各回轉(zhuǎn)軸線互相不平行。像我們要討論的那樣，尚有其他道理需要學(xué)習(xí)，掌握。</p><p>　　斜齒輪用于傳遞平行軸之間的運(yùn)動。傾斜角度每個(gè)齒輪都一樣，但一個(gè)必須右旋斜齒，而另一個(gè)必須是左旋斜齒。齒的形狀是一漸開線螺旋面。如果一張被剪成平行四邊形（矩形）的紙張包圍在齒輪圓柱體上，紙上印出齒的角刃邊就變成斜線。如果我展開這張紙，在血角刃邊上的每一個(gè)點(diǎn)就發(fā)生一漸開線曲線。</p><p>　

6、　直齒圓柱齒輪輪齒的初始接觸處是跨過整個(gè)齒面而伸展開來的線。斜齒輪輪齒的初始接觸是一點(diǎn)，當(dāng)齒進(jìn)入更多的嚙合時(shí)，它就變成線。在直齒圓柱齒輪中，接觸是平行于回轉(zhuǎn)軸線的。在斜齒輪中，該先是跨過齒面的對角線。它是齒輪逐漸進(jìn)行嚙合并平穩(wěn)的從一個(gè)齒到另一個(gè)齒傳遞運(yùn)動，那樣就使斜齒輪具有高速重載下平穩(wěn)傳遞運(yùn)動的能力。斜齒輪使軸的軸承承受徑向和軸向力。當(dāng)軸向推力變的大了或由于別的原因而產(chǎn)生某些影響時(shí)，那就可以使用人字齒輪。雙斜齒輪（人字齒輪）是與反向的

7、并排地裝在同一軸上的兩個(gè)斜齒輪等效。他們產(chǎn)生相反的軸向推力作用，這樣就消除了軸向推力。當(dāng)兩個(gè)或更多個(gè)單向齒斜齒輪被在同一軸上時(shí)，齒輪的齒向應(yīng)作選擇，以便產(chǎn)生最小的軸向推力。</p><p>　　交錯(cuò)軸斜齒輪或螺旋齒輪，他們是軸中心線既不相交也不平行。交錯(cuò)軸斜齒輪的齒彼此之間發(fā)生點(diǎn)接觸，它隨著齒輪的磨合而變成線接觸。因此他們只能傳遞小的載荷和主要用于儀器設(shè)備中，而且肯定不能推薦在動力傳動中使用。交錯(cuò)軸斜齒輪與斜齒輪

8、之間在被安裝后互相捏合之前是沒有任何區(qū)別的。它們是以同樣的方法進(jìn)行制造。一對相嚙合的交錯(cuò)軸斜齒輪通常具有同樣的齒向，即左旋主動齒輪跟右旋從動齒輪相嚙合。在交錯(cuò)軸斜齒設(shè)計(jì)中，當(dāng)該齒的斜角相等時(shí)所產(chǎn)生滑移速度最小。然而當(dāng)該齒的斜角不相等時(shí)，如果兩個(gè)齒輪具有相同齒向的話，大斜角齒輪應(yīng)用作主動齒輪。</p><p>　　蝸輪與交錯(cuò)軸斜齒輪相似。小齒輪即蝸桿具有較小的齒數(shù)，通常是一到四齒，由于它們完全纏繞在節(jié)圓柱上，因此它

9、們被稱為螺紋齒。與其相配的齒輪叫做蝸輪，蝸輪不是真正的斜齒輪。蝸桿和蝸輪通常是用于向垂直相交軸之間的傳動提供大的角速度減速比。蝸輪不是斜齒輪，因?yàn)槠潺X頂面做成中凹形狀以適配蝸桿曲率，目的是要形成線接觸而不是點(diǎn)接觸。然而蝸桿蝸輪傳動機(jī)構(gòu)中存在齒間有較大滑移速度的缺點(diǎn)，正像交錯(cuò)軸斜齒輪那樣。蝸桿蝸輪機(jī)構(gòu)有單包圍和雙包圍機(jī)構(gòu)。單包圍機(jī)構(gòu)就是蝸輪包裹著蝸桿的一種機(jī)構(gòu)。當(dāng)然，如果每個(gè)構(gòu)件各自局部地包圍著對方的蝸輪機(jī)構(gòu)就是雙包圍蝸輪蝸桿機(jī)構(gòu)。著兩者

10、之間的重要區(qū)別是，在雙包圍蝸輪組的輪齒間有面接觸，而在單包圍的蝸輪組的輪齒間有線接觸。一個(gè)裝置中的蝸桿和蝸輪正像交錯(cuò)軸斜齒輪那樣具有相同的齒向，但是其斜齒齒角的角度是極不相同的。蝸桿上的齒斜角度通常很大，而蝸輪上的則極小，因此習(xí)慣常規(guī)定蝸桿的導(dǎo)角，那就是蝸桿齒斜角的余角；也規(guī)定了蝸輪上的齒斜角，該兩角之和就等于90度的軸線交角。當(dāng)齒輪要用來傳遞相交軸之間的運(yùn)動時(shí)，就需要某種形式的錐齒輪。雖然錐齒輪通常制造成能構(gòu)成90度軸交角，但它們也可

11、產(chǎn)生任何角度的軸交</p><p>　　輪緣式內(nèi)膨脹制凍塊；</p><p>　　輪緣式外接觸制動塊；</p><p><b>　　條帶式；</b></p><p><b>　　盤型或軸向式；</b></p><p><b>　　圓錐型；</b><

12、/p><p><b>　　混合式。</b></p><p>　　分析摩擦離合器和制動器的各種形式都應(yīng)用一般的同樣的程序，下面的步驟是必需的：</p><p>　　假定或確定摩擦表面上壓力分布；</p><p>　　找出最大壓力和任一點(diǎn)處壓力之間的關(guān)系；</p><p>　　應(yīng)用靜平衡條件去找尋（a）作

13、用力；（b）扭矩；(c)支反力。</p><p>　　混合式離合器包括幾個(gè)類型，例如強(qiáng)制接觸離合器、超載釋放保護(hù)離合器、超越離合器、磁液離合器等等 。</p><p>　　強(qiáng)制接觸離合器由一個(gè)變位桿和兩個(gè)夾爪組成。各種強(qiáng)制接觸離合器之間最大的區(qū)別與夾爪的設(shè)計(jì)有關(guān)。為了在結(jié)合過程中給變換作用予較長時(shí)間周期，夾爪可以是棘輪式的，螺旋型或齒型的。有時(shí)使用許多齒或夾爪。他們可能在圓周面上加工齒，以

14、便他們以圓柱周向配合來結(jié)合或者在配合元件的端面上加工齒來結(jié)合。</p><p>　　雖然強(qiáng)制離合器不像摩擦接觸離合器用的那么廣泛，但它們確實(shí)有很重要的運(yùn)用。離合器需要同步操作。</p><p>　　有些裝置例如線性驅(qū)動裝置或電機(jī)操作螺桿驅(qū)動器必須運(yùn)行到一定的限度然后停頓下來。為著這些用途就需要超載釋放保護(hù)離合器。這些離合器通常用彈簧加載，以使得在達(dá)到預(yù)定的力矩時(shí)釋放。當(dāng)?shù)竭_(dá)超載點(diǎn)時(shí)聽到的“

15、喀嚓”聲就被認(rèn)定為是所希望的信號聲。</p><p>　　超越離合器或連軸器允許機(jī)器的被動構(gòu)件“空轉(zhuǎn)”或“超越”，因?yàn)橹鲃域?qū)動件停頓了或者因?yàn)榱硪粋€(gè)動力源使被動構(gòu)件增加了速度。這種離合器通常使用裝在外套筒和內(nèi)軸件之間的滾子或滾珠。該內(nèi)軸件，在它的周邊加工了數(shù)個(gè)平面。驅(qū)動作用是靠在套筒和平面之間契入的滾子來獲得。因此該離合器與具有一定數(shù)量齒的棘輪棘爪機(jī)構(gòu)等效。</p><p>　　磁液離合器

16、或制動器相對來說是一個(gè)新的發(fā)展，它們具有兩平行的磁極板。這些磁極板之間有磁粉混合物潤滑。電磁線圈被裝入磁路中的某處。借助激勵(lì)該線圈，磁液混合物的剪切強(qiáng)度可被精確的控制。這樣從充分滑移到完全鎖住的任何狀態(tài)都可以獲得。</p><p>　　附件2：外文原文（復(fù)印件）</p><p>　　GEAR AND SHAFT INTRODUCTION</p><p>　　Abst

17、ract: The important position of the wheel gear and shaft can't falter in traditional machine and modern machines.The wheel gear and shafts mainly install the direction that delivers the dint at the principal axis box

18、.The passing to process to make them can is divided into many model numbers, useding for many situations respectively.So we must be the multilayers to the understanding of the wheel gear and shaft in many ways .</p>

19、;<p>　　Key words: Wheel gear;Shaft</p><p>　　In the force analysis of spur gears, the forces are assumed to act in a single plane. We shall study gears in which the forces have three dimensions. The re

20、ason for this, in the case of helical gears, is that the teeth are not parallel to the axis of rotation. And in the case of bevel gears, the rotational axes are not parallel to each other. There are also other reasons, a

21、s we shall learn.</p><p>　　Helical gears are used to transmit motion between parallel shafts. The helix angle is the same on each gear, but one gear must have a right-hand helix and the other a left-hand hel

22、ix. The shape of the tooth is an involute helicoid. If a piece of paper cut in the shape of a parallelogram is wrapped around a cylinder, the angular edge of the paper becomes a helix. If we unwind this paper, each point

23、 on the angular edge generates an involute curve. The surface obtained when every point on the edge </p><p>　　The initial contact of spur-gear teeth is a line extending all the way across the face of the too

24、th. The initial contact of helical gear teeth is a point, which changes into a line as the teeth come into more engagement. In spur gears the line of contact is parallel to the axis of the rotation; in helical gears, the

25、 line is diagonal across the face of the tooth. It is this gradual of the teeth and the smooth transfer of load from one tooth to another, which give helical gears the ability to tran</p><p>　　Crossed-helica

26、l, or spiral, gears are those in which the shaft centerlines are neither parallel nor intersecting. The teeth of crossed-helical fears have point contact with each other, which changes to line contact as the gears wear i

27、n. For this reason they will carry out very small loads and are mainly for instrumental applications, and are definitely not recommended for use in the transmission of power. There is on difference between a crossed heli

28、cal gear and a helical gear until they are mou</p><p>　　Worm gears are similar to crossed helical gears. The pinion or worm has a small number of teeth, usually one to four, and since they completely wrap ar

29、ound the pitch cylinder they are called threads. Its mating gear is called a worm gear, which is not a true helical gear. A worm and worm gear are used to provide a high angular-velocity reduction between nonintersecting

30、 shafts which are usually at right angle. The worm gear is not a helical gear because its face is made concave to fit the curvatu</p><p>　　Worm gearing are either single or double enveloping. A single-envelo

31、ping gearing is one in which the gear wraps around or partially encloses the worm.. A gearing in which each element partially encloses the other is, of course, a double-enveloping worm gearing. The important difference b

32、etween the two is that area contact exists between the teeth of double-enveloping gears while only line contact between those of single-enveloping gears. The worm and worm gear of a set have the same hand of heli</p&g

33、t;<p>　　When gears are to be used to transmit motion between intersecting shaft, some of bevel gear is required. Although bevel gear are usually made for a shaft angle of 90 deg. They may be produced for almost an

34、y shaft angle. The teeth may be cast, milled, or generated. Only the generated teeth may be classed as accurate. In a typical bevel gear mounting, one of the gear is often mounted outboard of the bearing. This means that

35、 shaft deflection can be more pronounced and have a greater effect on the c</p><p>　　Straight bevel gears are easy to design and simple to manufacture and give very good results in service if they are mounte

36、d accurately and positively. As in the case of squr gears, however, they become noisy at higher values of the pitch-line velocity. In these cases it is often good design practice to go to the spiral bevel gear, which is

37、the bevel counterpart of the helical gear. As in the case of helical gears, spiral bevel gears give a much smoother tooth action than straight bevel gears, an</p><p>　　It is frequently desirable, as in the c

38、ase of automotive differential applications, to have gearing similar to bevel gears but with the shaft offset. Such gears are called hypoid gears because their pitch surfaces are hyperboloids of revolution. The tooth act

39、ion between such gears is a combination of rolling and sliding along a straight line and has much in common with that of worm gears.</p><p>　　A shaft is a rotating or stationary member, usually of circular c

40、ross section, having mounted upon it such elementsas gears, pulleys, flywheels, cranks, sprockets, and other power-transmission elements.</p><p>　　Shaft may be subjected to bending, tension, compression, or

41、torsional loads, acting singly or in combination with one another. When they are combined, one may expect to find both static and fatigue strength to be important design considerations, since a single shaft may be subjec

42、ted to static stresses, completely reversed, and repeated stresses, all acting at the same time.</p><p>　　The word “shaft” covers numerous variations, such as axles and spindles. Anaxle is a shaft, wither st

43、ationary or rotating, nor subjected to torsion load. A shirt rotating shaft is often called a spindle.</p><p>　　When either the lateral or the torsional deflection of a shaft must be held to close limits, th

44、e shaft must be sized on the basis of deflection before analyzing the stresses. The reason for this is that, if the shaft is made stiff enough so that the deflection is not too large, it is probable that the resulting st

45、resses will be safe. But by no means should the designer assume that they are safe; it is almost always necessary to calculate them so that he knows they are within acceptable limits. W</p><p>　　Although the

46、 von Mises-Hencky-Goodman method is difficult to use in design of shaft, it probably comes closest to predicting actual failure. Thus it is a good way of checking a shaft that has already been designed or of discovering

47、why a particular shaft has failed in service. Furthermore, there are a considerable number of shaft-design problems in which the dimension are pretty well limited by other considerations, such as rigidity, and it is only

48、 necessary for the designer to discover somethin</p><p>　　Because of the similarity of their functions, clutches and brakes are treated together. In a simplified dynamic representation of a friction clutch,

49、or brake, two in</p><p>　　ertias I1 and I2 traveling at the respective angular velocities W1 and W2, one of which may be zero in the case of brake, are to be brought to the same speed by engaging the clutch

50、or brake. Slippage occurs because the two elements are running at different speeds and energy is dissipated during actuation, resulting in a temperature rise. In analyzing the performance of these devices we shall be int

51、erested in the actuating force, the torque transmitted, the energy loss and the temperature rise. T</p><p>　　Rim type with internally expanding shoes</p><p>　　Rim type with externally contractin

52、g shoes</p><p><b>　　Band type</b></p><p>　　Disk or axial type</p><p><b>　　Cone type</b></p><p>　　Miscellaneous type</p><p>　　The an

53、alysis of all type of friction clutches and brakes use the same general procedure. The following step are necessary:</p><p>　　Assume or determine the distribution of pressure on the frictional surfaces.</

54、p><p>　　Find a relation between the maximum pressure and the pressure at any point</p><p>　　Apply the condition of statical equilibrium to find (a) the actuating force, (b) the torque, and (c) the

55、support reactions.</p><p>　　Miscellaneous clutches include several types, such as the positive-contact clutches, overload-release clutches, overrunning clutches, magnetic fluid clutches, and others.</p>

56、;<p>　　A positive-contact clutch consists of a shift lever and two jaws. The greatest differences between the various types of positive clutches are concerned with the design of the jaws. To provide a longer perio

57、d of time for shift action during engagement, the jaws may be ratchet-shaped, or gear-tooth-shaped. Sometimes a great many teeth or jaws are used, and they may be cut either circumferentially, so that they engage by cyli

58、ndrical mating, or on the faces of the mating elements.</p><p>　　Although positive clutches are not used to the extent of the frictional-contact type, they do have important applications where synchronous op

59、eration is required.</p><p>　　Devices such as linear drives or motor-operated screw drivers must run to definite limit and then come to a stop. An overload-release type of clutch is required for these applic

60、ations. These clutches are usually spring-loaded so as to release at a predetermined toque. The clicking sound which is heard when the overload point is reached is considered to be a desirable signal.</p><p>

61、;　　An overrunning clutch or coupling permits the driven member of a machine to “freewheel” or “overrun” because the driver is stopped or because another source of power increase the speed of the driven. This type of clut

62、ch usually uses rollers or balls mounted between an outer sleeve and an inner member having flats machined around the periphery. Driving action is obtained by wedging the rollers between the sleeve and the flats. The clu

63、tch is therefore equivalent to a pawl and ratchet with an infin</p><p>　　Magnetic fluid clutch or brake is a relatively new development which has two parallel magnetic plates. Between these plates is a lubri

64、cated magnetic powder mixture. An electromagnetic coil is inserted somewhere in the magnetic circuit. By varying the excitation to this coil, the shearing strength of the magnetic fluid mixture may be accurately controll