普通車床的主軸箱設(shè)計(jì)機(jī)械課程畢業(yè)設(shè)計(jì)外文文獻(xiàn)翻譯@中英文翻譯@外文翻譯

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： 鄧志武 學(xué) 號(hào)： 05211512 2015年 3 月 19 日 外文資料翻譯譯文 普通車床的主軸箱設(shè)計(jì) 主軸箱組件緊固在車床左端。它由主軸箱主軸組成，經(jīng)齒輪或齒輪組和皮帶輪使主軸旋轉(zhuǎn)。主軸有可裝夾并轉(zhuǎn)動(dòng)工件的附件。主軸有多級(jí)轉(zhuǎn)速。主軸箱由 35 個(gè)支座支承。由于車 床上工件的加工精度取決于夾持工件的主軸旋轉(zhuǎn)軸的精度，故必須十分仔細(xì)地制造和安裝主軸及其所有附件。 主軸本身有一個(gè)通孔，這個(gè)孔的前端是一錐孔，可用來(lái)安裝帶錐柄的刀具。安裝主軸箱活頂尖時(shí)，用一錐套配入主軸的錐孔內(nèi)。主軸箱頂尖可隨工件旋轉(zhuǎn)，故可稱活頂尖。它是一個(gè)帶尖端的錐金屬件。工件旋轉(zhuǎn)時(shí)可用來(lái)支承工件，所有車床頂尖均為 60角。 在主軸上安裝附件，常使用三種通用的主軸頭： 1. 螺紋主軸頭 車床上最常用的是螺紋主軸頭。將安裝的附件擰到主軸上，直到與主軸法蘭盤(pán)緊密相配。螺紋主軸頭的主要缺點(diǎn)是不能進(jìn)行反向車削，因有 些附件（例如卡盤(pán)）反向時(shí)會(huì)松開(kāi)。 2. 凸輪鎖緊主軸頭 凸輪鎖緊主軸頭有一個(gè)非常短的錐體，她可以配入花盤(pán)或卡盤(pán)背面的錐槽內(nèi)。從花盤(pán)或卡盤(pán)背面伸出許多凸輪鎖緊短軸，這些短軸可配入主軸頭的孔內(nèi)。轉(zhuǎn)動(dòng)這些凸輪就可將它們鎖緊在規(guī)定位置。 3. 長(zhǎng)錐鍵傳動(dòng)主軸頭 它有一個(gè)很長(zhǎng)的錐體。錐體帶一附加鍵和一內(nèi)螺紋套爪?；ūP(pán)或卡盤(pán)必須與其錐度相同并帶有外螺紋鍵槽。這種正向鎖緊型主軸在中型車床中最為普遍。它允許主軸在正向或反向旋轉(zhuǎn)時(shí)均能切削。 驅(qū)動(dòng)主軸的動(dòng)力由一電動(dòng)機(jī)供給，從電動(dòng)機(jī)將動(dòng)力傳遞給主軸有四種常用的方法： 平皮帶傳動(dòng) 在大多數(shù)皮帶傳動(dòng)的車床中，直接驅(qū)動(dòng)動(dòng)力通過(guò)皮帶傳遞給附在主軸的塔輪上。把皮帶移動(dòng)到塔輪的不同位置，就可改變主軸速度。為獲得較低速和較大動(dòng)力，可使用背輪。 背輪的工作原理見(jiàn)圖 2-3。齒輪 F 緊固在主軸上，常稱齒輪 F為大齒輪。塔輪的小端有一小齒輪 E。塔輪轉(zhuǎn)動(dòng)時(shí)，齒輪 E 總是轉(zhuǎn)的。塔輪的小齒輪通過(guò)一個(gè)稱作大齒輪鎖緊銷的滑動(dòng)銷與大齒輪相連。床頭箱背面有兩個(gè)安裝在同一軸上的齒輪。它們間隔排開(kāi)，與大齒輪 F 和小齒輪 E 相嚙合。這些齒輪叫背輪。為了使背輪嚙合，要推出大齒輪銷子（此銷子推出時(shí)，塔輪和小齒輪轉(zhuǎn)動(dòng)而主軸不轉(zhuǎn)）。向前推 背輪手柄，使背輪與大齒輪 F和小齒輪 E相嚙合。接通電源時(shí)，決不能用手轉(zhuǎn)動(dòng)塔輪使其嚙合。嚙合時(shí)，動(dòng)力直接由背輪傳遞給大齒輪 F和主軸。 床頭箱左端有一反向進(jìn)給桿。它用于絲杠的反向運(yùn)動(dòng)。此桿有三個(gè)位置。在上自動(dòng)進(jìn)給位置時(shí)，床鞍將向床頭箱方向（即向左）移動(dòng)，橫進(jìn)給向外運(yùn)動(dòng)。 三角皮帶傳動(dòng) 每個(gè)皮帶輪的圓周上都開(kāi)有一個(gè) V型槽。三角皮帶將精確地嵌入槽內(nèi)。三角皮帶不能碰到皮帶輪的底部。這種傳動(dòng)方式也有一個(gè)與平皮帶傳動(dòng)相似的背輪裝置。 無(wú)級(jí)變速傳動(dòng) 這種裝置不用停車就可以改變主動(dòng)輪和從動(dòng)輪間的速度。實(shí)際上只有在機(jī)床運(yùn)行時(shí)才需 變速。無(wú)級(jí)變速傳動(dòng)的傳動(dòng)皮帶輪由二個(gè) V 型側(cè)面的半輪組成。皮帶輪的一側(cè)可以是打開(kāi)的，即與另一側(cè)脫開(kāi)。在脫開(kāi)時(shí)，皮帶就向里移動(dòng)到較小直徑，使從動(dòng)輪產(chǎn)生較低速度。當(dāng)皮帶輪兩側(cè)合在一起時(shí)，就迫使皮帶輪向外移動(dòng)到較大直徑，使從動(dòng)輪速度增大?？梢杂檬謩?dòng)或液壓進(jìn)行變速。采用液壓方式時(shí)，床頭箱頂部的控制盤(pán)可使液壓系統(tǒng)精確動(dòng)作。電動(dòng)機(jī)停止時(shí)，不要轉(zhuǎn)此控制盤(pán)。直接傳動(dòng)的轉(zhuǎn)速范圍為 3001600轉(zhuǎn) /分。 4. 齒輪傳動(dòng)變速箱 這種床頭箱包括齒輪和變速機(jī)構(gòu)，可獲得許多不同的轉(zhuǎn)速。操作者可使用附在床頭箱上的速度分度盤(pán)來(lái)選擇所需的速 度。移動(dòng)兩個(gè)或三個(gè)手柄或搖手就可調(diào)節(jié)速度。 外文原文 Headstock of Engine Lathe The headstock assembly is permanently fastened to the left end of the lathe. It contains the headstock spindle, which is rotated by gears or by a combination of gear and pulleys. The spindle holds the attachments which, in turn, hold and turn the workpiece. Spindles come in several quality ratings and are supported in headstocks by three to five bearings. Since the accuracy of the work done on a lathe depends on the axis of rotation of the spindle holding the workpiece, the spindle and all its accessories must be built and assemble with the greatest possible care. A hold extends through the spindle itself. The front end of this hole is tapered for holding tools having a tapered shank. A taper sleeve (a hollow-round part) fits into the taper spindle hole, when holding a headstock, or live center. The headstock center is called a live center because it turns with the work. The center is a tapered metal part with a pointed end. It is used to support the end of a workpiece as it is being turned. All lathe center point have a 60-degree() included angle. Three common types of spindle noses are used to hold attachments on the spindle. 1. The threaded spindle nose has been used on lathes longer than any of the other types. Attachments to be mounted are screwed onto the spindle until they fit firmly against the spindle flange. The major disadvantage of the threaded spindle nose is that turning cannot be done in the reverse position (with the spindle turning clockwise). This is Because certain attachments, a chuck for example, would come loose. 2. The cam lock spindle nose has a very short taper which fits into a tapered recess in the back of a faceplate or chuck. A series of cam lock studs projects from the back of the faceplate or chuck. These cam lock studs fit into the hole in the spindle nose. They are locked into position by turning a series of cams. 3. The long (steep) taper key drive spindle nose has a long taper with a key attached and an internal threaded collar. The faceplate or chuck must have an equal taper and keyway plus an external thread. This positive lock-type of spindle is most popular on medionum-size lathes. It permits cutting with the spindle turning in either direction. Power for driving the spindle is provided by an electric motor. There are four common ways of transmitting the power form the electric motor to the spindle. These include: Flat belt drive. On most belt-driven lathes, direct drive power is delivered through belts to a step pulley attached to the spindle. The spindle speed is changed by moving the belt to different positions on the step pulley. To obtain slower speeds and more powder, back gears are used. To understand how the back gears operate, study Fig, 2-3 Notice that gear F is fastened securely to the spindle. This gear is often called a bull gear. The small end of the step pulley gas a small gear attached to it called a pinion gear. This gear (E) always turns when the pulley turns. The step pulley and pinion gear are connected with the bull gear by a sliding pin called the bull-gear lock-pir. At the back of the headstock are two gears mounted on the same shaft. They are spaced to line up or mesh with the bull gear (F) and pinion gear (E). These are called back gears. To engage the back gear, the pin in the bull gear is pulled out (when the pin is out, the pulley and pinion gear will turn, but the spindle will not turn). Pull the back gear handle forward to mesh the back gears with bull gear F and pinion gear E. Do this by turning the step pulley by hand-never while the power is on. When engaged, power is delivered directly to the bull gear (F) and spindle by the back gears. At the left end of the headstock assembly is a feed reverse lever. It is used for reversing, the direction or movement of the lead screw. This lever can be moved to three positions. When it is in the upper position with the automatic feed engaged, the carriage will move to-ward the headstock (to the left) and the cross-feed will move in. When in the center position, the gears are out of mesh and the lead screw will not move. When in the lower position with the automatic feed engaged, the carriage will move toward the tailstock (to the right) and the cross-feed will move out. V-belt drive. A V-shaped groove is cut around the circumference of each pulley, and a V belt fits accurately into this groove. The V belt does not touch the bottom of the pulley. This type of drive has a back gear arrangement similar to that used on flat belt machines. Variable-speed driver. In this arrangement it is possible to change the speed between the driver and driven pulleys without stopping the lathe. In fact, the speed must be changed only when the machine is running. The driving pulley of a variable-speed drive is made with parts having V-shaped sides. One side of the pulley may be opened or spread apart from the other side. As it spreads apart, the belt moves inward toward the smaller diameter, producing a slower speed on the driven pulley. As the sides of the pulley are brought together, the belt is forced outward toward the large diameter which increases the