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中國(guó)地質(zhì)大學(xué)長(zhǎng)城學(xué)院 本科畢業(yè)設(shè)計(jì)外文資料翻譯 系 別: 工程技術(shù)系 專 業(yè): 機(jī)械設(shè)計(jì)制造及其自動(dòng)化 姓 名: 趙政闊 學(xué) 號(hào): 05211619 2015 年 4 月 17 日 外文資料翻譯譯文 車床和銑床 一家 工廠 擁有一臺(tái)銑床和車床能加工幾乎任何類型的大小適合的產(chǎn)品。 設(shè)計(jì)主要是做把基本的機(jī)器稱為車床,鏜。車削很少在其他種類的機(jī)床上進(jìn)行,而不可以用同樣的設(shè) 備做。由于車床可以做無(wú)聊,面對(duì),鉆,鉸除將其通用性,允許多個(gè)操作將工件在一次安裝完成。這說(shuō)明各種車床的更廣泛的應(yīng)用于制造比任何其他機(jī)床。 車床已經(jīng)存在了超過(guò)二千年。現(xiàn)代車床可以追溯到大約 1797,當(dāng)亨利 莫德斯利發(fā)明了一種具有絲杠。它提供了控制,工具的機(jī)械進(jìn)給。這個(gè)聰明的英國(guó)人還發(fā)明了一個(gè)可以連接主軸和絲杠可以切削螺紋變速齒輪系統(tǒng)。 車床結(jié)構(gòu)。車床的主要部件是畫面的框圖描述。這些都是床,主軸箱,尾座組件,拖板組件,快速更換變速箱、絲杠和光杠。 床身是車床的背骨。它通常是由歸一化的老年灰鑄鐵或球墨鑄鐵提供了重 ,剛性框架,所有其他基本部件都安裝在。兩組平行,縱向方面,內(nèi)部和外部的,包含在床上,通常在上面。一些制造商使用一個(gè)倒 V 形的所有四個(gè)方面,而有些人則利用一個(gè)倒 V 和一個(gè)或兩個(gè)平面導(dǎo)軌。由于其他的部件安裝和 /或移動(dòng)要經(jīng)過(guò)精密加工,確保精度的對(duì)齊方式。同樣,適當(dāng)?shù)念A(yù)防應(yīng)采取的操作車床,以確保道路不損壞。在導(dǎo)軌上的任何誤差,通常意味著整個(gè)機(jī)床的精度遭到破壞。大多數(shù)現(xiàn)代車床的導(dǎo)軌淬火處理提供更大的抗磨損表面。 主軸箱安裝在固定位置的內(nèi)側(cè)導(dǎo)軌床身一端。它提供動(dòng)力,意味著以不同的速度旋轉(zhuǎn)的工作。它包括,從本質(zhì)上講,一個(gè)空心 軸,安裝在精密軸承,和一套傳動(dòng)齒輪 類似于卡車傳輸 通過(guò)主軸可以在不同速度轉(zhuǎn)動(dòng)。大多數(shù)車床提供從八到十八的速度,通常以幾何比例,而且在現(xiàn)代機(jī)床的速度可以從兩到四桿只得到。一個(gè)不斷增長(zhǎng)的趨勢(shì)是通過(guò)電氣或機(jī)械傳動(dòng)無(wú)級(jí)變速。 由于機(jī)床的精度在很大程度上取決于主軸,它是重型施工和安裝在重型軸承,圓錐滾子或球型通常預(yù)裝。 長(zhǎng)剖面孔延伸通過(guò)主軸使長(zhǎng)棒料可以通過(guò)它。這個(gè)洞的大小是車床的一個(gè)重要尺寸,因?yàn)樗鼪Q定了棒料的最大尺寸,可加工的材料時(shí),必須通過(guò)主軸。 主軸的內(nèi)端伸出齒輪箱中安裝各種型號(hào)的卡盤,工具面板,在它的狗 盤。而小車床通常采用螺紋部分的夾頭擰,很多大車床使用凸輪鎖或鑰匙動(dòng)圓錐。這提供了一個(gè)大直徑錐形保證卡盤的精確對(duì)準(zhǔn),和一種機(jī)制,使得卡盤或花盤被鎖定或解鎖位置不用旋轉(zhuǎn)這些笨重的附件的必要性。 電主軸由電動(dòng)機(jī)通過(guò) V 帶或無(wú)聲鏈傳動(dòng)。大多數(shù)現(xiàn)代車床有汽車從 5 到 15 馬力在高速切削硬質(zhì)合金和陶瓷工具提供充足的電力。 尾座組件由三部分組成,從本質(zhì)上講。較低的鑄造適合在床內(nèi)的方法和縱向滑動(dòng)上,用在任意位置上夾緊的裝置全部組裝。上的鑄造適合低的一個(gè)可橫向移動(dòng)時(shí)對(duì)某些類型的輸入方式。橫向移動(dòng)使尾座 與主軸箱主軸對(duì)準(zhǔn)了車削圓錐的方 法。組件的第三部分是尾架套筒。這是一個(gè)中空的圓柱體,通常 2 到 3 英寸直徑,可以移動(dòng)幾英寸在縱向上鑄造通過(guò)手輪和螺桿裝置。套筒的開(kāi)口端終止于莫氏錐度的車削中心,或各種工具如鉆頭,可以舉行??潭瘸撸瑤子⒋玳L(zhǎng),通常是刻在外面的羽毛來(lái)幫助其運(yùn)動(dòng)控制和移出。鎖定裝置可以使夾緊套筒在任何需要的位置。 托架組件提供安裝和移動(dòng)切削工具的方法。車廂是一個(gè)相對(duì)平坦的 H 形鑄件,睡在床上的外套移動(dòng)方式。車廂的橫杠上包含方式導(dǎo)軌安裝,可以由一個(gè)螺旋進(jìn)給,是由一個(gè)小的手輪和刻度盤控制裝置移動(dòng)。通過(guò)交叉滑動(dòng)裝置設(shè)置在垂直于旋轉(zhuǎn)軸的工作方向移動(dòng)車刀。 大多數(shù)車床刀架上安裝在刀架。這包括底座,底座安裝在橫拖板上,可繞一垂直軸,和上鑄造。上刀架安裝在底座上,可以前后移動(dòng),通過(guò)手輪和刻度盤控制一個(gè)短絲杠的方式。 手工和動(dòng)力驅(qū)動(dòng)大拖板,和十字滑動(dòng)力的運(yùn)動(dòng),是由機(jī)制內(nèi)的圍裙,附著到馬車前。沿床馬車手動(dòng)運(yùn)動(dòng)是通過(guò)轉(zhuǎn)動(dòng)手輪上的圍裙前面的影響,這是面向背面齒輪。這個(gè)小齒輪接合架裝在床前面的上邊緣在一個(gè)倒置的位置。 可以將動(dòng)力傳遞給運(yùn)輸和跨幻燈片,設(shè)置旋轉(zhuǎn)桿。飼料桿,其中包含一個(gè)鍵槽在大多數(shù)它的長(zhǎng)度,通過(guò)兩倒錐齒輪和鍵控他們。無(wú)論是小齒輪凸輪被帶進(jìn)一個(gè)交配的錐 齒輪嚙合的換向手柄的圍裙前面的手段,從而為“前進(jìn)”或“反向”權(quán)力的馬車。適當(dāng)?shù)碾x合器連接的齒輪齒條或橫向滑動(dòng)螺釘提供運(yùn)輸或橫拖板橫向運(yùn)動(dòng)的縱向運(yùn)動(dòng)。 對(duì)于螺紋加工,第二縱向傳動(dòng)絲杠提供了。而車廂的運(yùn)動(dòng)時(shí),帶動(dòng)絲桿機(jī)構(gòu)發(fā)生通過(guò)摩擦離合器打滑是可能的,通過(guò)絲杠的運(yùn)動(dòng)是由一個(gè)直接,圍裙和絲杠之間的機(jī)械連接。這是由一個(gè)螺母劈開(kāi)了。由一個(gè)夾桿上的圍裙前面的手段,對(duì)開(kāi)螺母可以圍繞合絲杠。當(dāng)對(duì)開(kāi)螺母閉合時(shí),馬車沿著絲杠直接驅(qū)動(dòng)沒(méi)有出現(xiàn)打滑的可能性。 現(xiàn)代車床有一個(gè)變速齒輪箱。該變速器輸入端,通過(guò)合適的齒輪傳動(dòng)驅(qū)動(dòng)由車床主軸。該齒輪箱的輸出端連接到光桿和絲桿。因此,通過(guò)齒輪傳動(dòng),從主軸導(dǎo)致快速更換變速箱,再帶動(dòng)絲杠和光杠,然后馬車,刀具可以移動(dòng)一個(gè)特定的距離,無(wú)論是縱向或橫向 。 一些老式的和一些便宜的車床,一個(gè)或兩個(gè)齒輪在傳動(dòng)軸和變速齒輪箱之間必須改變,以獲得全方位的線程和飼料。 銑削是一種基本的加工過(guò)程中,表面被逐漸形成并從工件因?yàn)檫@是美聯(lián)儲(chǔ)為垂直于旋轉(zhuǎn)刀具的刀軸方向去除切屑材料產(chǎn)生。在某些情況下,工件是固定的,刀是美聯(lián)儲(chǔ)的工作。在大多數(shù)情況下,使用多齒刀具,金屬去除率高,并且經(jīng)常所需的表面是通過(guò)在一個(gè)單一的工作了。 在銑 削加工中使用的刀具稱為銑刀。它通常是由一個(gè)圓柱體繞其軸線旋轉(zhuǎn)并且包含等距周圍的牙齒,間歇性接觸和切割工件。在某些情況下,牙齒伸出的一端或兩端的氣缸。 由于銑削提供了快速去除金屬和能產(chǎn)生良好的表面光潔度,故特別適合大規(guī)模生產(chǎn)的工作,和優(yōu)秀的銑床已為此目的而開(kāi)發(fā)的。然而,非常精確的多功能通用性銑床也已經(jīng)廣泛應(yīng)用于車間和工具模具工作。一家擁有一臺(tái)銑床和車床能加工幾乎任何類型的大小適合的產(chǎn)品。 銑削操作類型。銑削操作可分為兩大類,其中有幾個(gè)變化: 基本概念的周邊和端面銑削圖外圍銑削通常具有水平主軸的機(jī)器進(jìn)行說(shuō)明,而 銑刀在水平和垂直主軸的機(jī)器做的。 在銑削表面生成。表面可以采用兩種完全不同的方法在圖注意了銑削刀具旋轉(zhuǎn)方向與工件進(jìn)給銑削產(chǎn)生的描述,而在順銑輪在同一方向的飼料。如圖所示,切屑形成的方法是完全不同的兩種情況。在逆銑的髖關(guān)節(jié)是非常薄的開(kāi)始,其中齒首先接觸的工作,并增加厚度,將最大的齒葉的工作。刀具有推動(dòng)工作,把它上升到表。這個(gè)動(dòng)作會(huì)消除進(jìn)給螺桿和螺母的銑床工作臺(tái)和結(jié)果在一個(gè)光滑的切割松動(dòng)任何效果。然而,行動(dòng)也趨于寬松的工作由夾緊裝置,夾緊必須采用更大的報(bào)酬。此外,生成的表面光潔度主要取決于切削刃的鋒利。 順銑時(shí) ,最大切屑厚度出現(xiàn)在接近在該點(diǎn)的齒接觸的工作。由于相對(duì)運(yùn)動(dòng)能把工件向刀具,在進(jìn)給螺桿可能產(chǎn)生的松動(dòng)必須如果采用順銑法消除。它不應(yīng)該試圖在機(jī)器,是不適合這個(gè)類型的銑削。在如同物質(zhì)產(chǎn)量大約在切線方向上的齒嚙合的一端,有更少的趨勢(shì),加工表面痕時(shí)使用比逆銑。另一個(gè)可考慮的優(yōu)勢(shì),順銑切削力趨于將工作與機(jī)床工作臺(tái),允許較低的夾緊力可以。這是特別有利于加工薄工件或進(jìn)行強(qiáng)力切削。 有時(shí),順銑的弱點(diǎn)是,刀齒撞擊工件表面在每個(gè)芯片的開(kāi)始。當(dāng)工件表面堅(jiān)硬,像鑄件,這可能會(huì)導(dǎo)致牙齒很快變鈍。 銑刀可分幾個(gè)方面。一種方法是將它們分為 兩大類,如下: 1.仿形銑刀每齒上磨了一個(gè)很小的土地上的切削刃的背面浮雕。切削刃可以是直的或彎曲的。 2.在形式或凸輪減輕刀具截面各齒在切削刃偏心曲線,從而提供救濟(jì)。偏心后角的各部分,與切削刃平行,必須具有相同的輪廓切削刃。這類刀具磨削的齒面磨,與輪廓的切割邊緣保持不變。 另一個(gè)有用的分類方法是根據(jù)銑刀安裝的方法。喬木刀是一個(gè)中心孔,這樣他們可以安裝在心軸。帶柄銑刀有一錐柄或直柄軸。那些錐形柄可以直接安裝在銑床的主軸上,而直柄刀具裝在卡盤。平面銑刀通常用螺栓固定在刀軸的端銑刀的類型。平銑刀圓柱或圓盤狀,邊緣 上有直的或螺旋形的牙齒。他們是用于銑削平面。這種類型的操作稱為平面或平面銑削。在一個(gè)螺旋銑刀每齒嚙合工作逐步,通常超過(guò)一齒切在一個(gè)給定的時(shí)間。這減少了震動(dòng)和抖動(dòng)的傾向和促進(jìn)一個(gè)光滑的表面。因此,這種類型的銑刀通常優(yōu)于與直齒。側(cè)銑刀類似平面銑刀除了齒徑向延伸的一端或兩端向中心筒。牙齒可以是直的或螺旋形的。經(jīng)常這些刀具相對(duì)較窄,具有盤形的形狀。兩個(gè)或兩個(gè)以上的側(cè)銑刀通常間隔對(duì)喬木進(jìn)行同時(shí),平行切割,稱為跨銑 。 槽銑刀是由兩個(gè)刀類似于米爾斯身邊,但是作為一個(gè)單元進(jìn)行銑槽。兩刀具調(diào)整到所需寬度之間插入墊片。 錯(cuò)齒銑刀是狹窄的圓柱形銑刀具有交錯(cuò)的牙齒,和交替齒具有相反的螺旋角。他們地切只在外圍,但每個(gè)齒也有芯片清除地面上的凸側(cè)。這些刀有一個(gè)免費(fèi)的切割作用,使得它們?cè)阢娚畈厶貏e有效。金屬鋸薄,平面銑刀,一般從 1 / 32 到 3 / 16 英寸厚,有其兩面稍“拋出”提供間隙,防止結(jié)合。他們通常有牙每英寸直徑比普通銑刀用于銑削深多,窄槽和切斷操作。 外文原文 LATHES & MILLING A shop that is equipped with a milling machine and an engine lathe can machine almost any type of product of suitable size. The basic machines that are designed primarily to do turning, facing and boring are called lathes. Very little turning is done on other types of machine tools, and none can do it with equal facility. Because lathe can do boring, facing, drilling, and reaming in addition to turning, their versatility permits several operations to be performed with a single setup of the workpiece. This accounts for the fact that lathes of various types are more widely used in manufacturing than any other machine tool. Lathes in various forms have existed for more than two thousand years. Modern lathes date from about 1797, when Henry Maudsley developed one with a leads crew. It provided controlled, mechanical feed of the tool. This ingenious Englishman also developed a change gear system that could connect the motions of the spindle and leadscrew and thus enable threads to be cut. Lathe Construction. The essential components of a lathe are depicted in the block diagram of picture. These are the bed, headstock assembly, tailstock assembly, carriage assembly, quick-change gearbox, and the leadscrew and feed rod. The bed is the back bone of a lathe. It usually is made of well-normalized or aged gray or nodular cast iron and provides a heavy, rigid frame on which all the other basic components are mounted. Two sets of parallel, longitudinal ways, inner and outer, are contained on the bed, usually on the upper side. Some makers use an inverted V-shape for all four ways,whereas others utilize one inverted V and one flat way in one or both sets. Because several other components are mounted and/or move on the ways they must be made with precision to assure accuracy of alignment. Similarly, proper precaution should betaken in operating a lathe to assure that the ways are not damaged. Any inaccuracy in them usually means that the accuracy of the entire lathe is destroyed. The ways on most modern lathes are surface hardened to offer greater resistance to wear and abrasion. The headstock is mounted in a fixed position on the inner ways at one end of the lathe friction clutch in which slippage is possible, motion through the lead screw is by a direct,mechanical connection between the apron and the lead screw. This is achieved by a split nut. By means of a clamping lever on the front of the apron, the split nut can be closed around the lead screw. With the split nut closed, the carriage is moved along the lead screw by direct drive without possibility of slippage. Modern lathes have a quick-change gear box. The input end of this gearbox is driven from the lathe spindle by means of suitable gearing. The out put end of the gear box is connected to the feed rod and lead screw. Thus, through this gear train, leading from the spindle to the quick-change gearbox, thence to the lead screw and feed rod, and then to the carriage, the cutting tool can be made to move a specific distance, either longitudinally or transversely, for each revolution of the spindle. A typical lathe provides, through the feed rod,forty-eight feeds ranging from 0.002 inch to0.118 inch per revolution of the spindle, and,through the lead screw , leads for cutting forty-eight different threads from 1.5 to 92perinch.On some older and some cheaper lathes, one or two gears in the gear train between the spindle and the change gear box must be changed in order to obtain a full range of threads and feeds. Milling is a basic machining process in which the surface is generated by the progressive formation and removal of chips of material from the workpiece as it is fed to a rotating cutter in a direction perpendicular to the axis of the cutter. .In some cases the workpiece is stationary and the cutter is fed to the work. In most instances a multiple-tooth cutter is used so that the metal removal rate is high, and frequently the desired surface is obtained in a single pass of the work. The tool used in milling is known as a milling cutter. It usually consists of a cylindrical body which rotates on its axis and contains equally spaced peripheral teeth that intermittently engage and cut the workpiece. In some cases the teeth extend part way across one or both ends of the cylinder. Because the milling principle provides rapid metal removal and can produce good surface finish, it is particularly well-suited for mass-production work, and excellent milling machines have been developed for this purpose. However, very accurate and versatile milling machines of a general-purpose nature also have been developed that are widely used in job-shop and tool and die work. A shop that is equipped with a milling machine and an engine lathe can machine almost any type of product of suitable size. Types of Milling Operations. Milling operations can be classified into two broad categories, each of which has several variations: The basic concepts of peripheral and face milling are illustrated in Fig. Peripheral milling operations usually are performed on machines having horizontal spindles, whereas face milling is done on both horizontal-and vertical-spindle machines. Surface Generation in Milling. Surfaces can be generated in milling by two distinctly different methods depicted in Fig. Note that in up milling the cutter rotates against the direction of feed the workpiece, whereas in down milling the rotation is in the same direction as the feed .As shown in Fig., the method of chip formation is quite different in the two cases. In up milling the c hip is very thin at the beginning, where the tooth first contacts the work,and increases in thickness, be-coming a maximum where the tooth leaves the work. The cutter tends to push the work along and lift it upward from the table. This action tends to eliminate any effect of looseness in the feed screw and nut of the milling machine table and results in a smooth cut. However, the action also tends to loosen the work from the clamping device so that greater clamping forcers must be employed. In addition, the smoothness of the generated surface depends greatly on the sharpness of the cutting edges. In down milling, maximum chip thickness occurs close to the point at which the tooth contacts the work. Because the relative motion tends to pull the workpiece into the cutter, all possibility of looseness in the table feed screw must be eliminated if down milling is to be used. It should never be attempted on machines that are not designed for this type of milling. In as mush as the material yields in approximately a tangential direction at the end of the tooth engagement, there is much less tendency for the machined surface to show tooth marks than when up milling is used. Another consider able advantage of down milling is that the cutting force tends to hold the work against the machine table, permitting lower clamping force to be employed. This is particularly advantageous when milling thin workpiece or when taking heavy cuts. Sometimes a disadvantage of down milling is that the cutter teeth strike against the surface of the work at the beginning of each chip. When the workpiece has a hard surface,such as castings do, this may cause the teeth to dull rapidly. Milling Cutters. Milling cutters can be classified several ways. One method is to group them into two broad classes, based on tooth relief, as follows: 1. Profile-cutters have relief provided on each tooth by grinding a small land back of the cutting edge. The cutting edge may be straight or curved. 2.In form or cam-relieved cutters the cross section of each tooth is an eccentric curve behind the cutting edge, thus providing relief. All sections of the eccentric relief, parallel with the cutting edge, must have the same contour as the cutting edge. Cutters of this type are sharpened by grinding only the face of the teeth, with the contour of the cutting edge thus remaining unchanged. Another useful method of classification is according to the method of mounting the cutter. Arbor cutters are those that have a center hole so they can be mounted on an arbor. Shank cutters have either tapered or straight integral shank. Those with tapered shanks can be mounted directly in the milling machine spindle, whereas straight-shank cutters are held in a chuck. Facing cutters usually are bolted to the end of a stub arbor.Types of Milling Cutters. Plain milling cutters are cylindrical or disk-shaped, having straight or helical teeth on the periphery. They are used for milling flat surfaces. This type of operation is called plain or slab milling. Each tooth in a helical cutter engages the work gradually, and usually more than one tooth cuts at a given time. This reduces shock and chattering tendencies and promotes a smoother surface. Consequently,
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