1、Unit 7 LathesContentslNew Words&Expressions lText&TranslationlComplex Sentence AnalysislKey to ExercisesNew Words&Expressions llathe lei n.车床 vt.车床加工lengine lathe 普通车床lbench model 台式车床ltracer or duplicating lathe 靠模车床或仿形车床ltemplate templit n.(切金属、石、木等用的)样板,模板,型板ltapered teipd adj.锥形的lgroove gru:v n.
2、沟，槽lcontour kntu n.轮廓；轮廓线lshaft:ft n.轴New Words&Expressions lcar axleksl n.汽车轴lturbine t:bin n.汽轮机lturret t:rit n.转台；转塔ltailstock teilstk n.尾座，尾架laccessory ksesri n.附件，配件lprincipal prinspl adj.主要的lscrew skru:n.螺丝，螺钉lcasting k:sti n.铸件，铸造New Words&Expressions lforging f:di n.锻造；锻件lbar stock 棒料lcollet
3、 klit n.夹头lattachment ttmnt n.附件lspindle spindl n.主轴lreversal riv:sl n.反转；逆转lvertical v:tikl adj.立式的；垂直的lmachine center 加工中心Text&TranslationlLathes are widely used in manufacturing to produce a great variety of machine parts.Some are used for general purposes and others are used to perform specializ
4、ed operations.l1.Engine Lathesl1Engine lathes，of course，are general purpose machines used in production and maintenance shops all over the world.Sizes range from small bench models to huge heavy duty pieces of equipment.Many of the larger lathes are equipped with auxiliary parts which are not common
5、ly available in ordinary shops，such as automatic stops for the carriage.Text&Translationl2.Tracer or Duplicating LatheslThe tracer or duplicating lathe is designed to produce irregularly shaped parts automatically.The basic operation of this lathe is as follows.A template of either a flat or three d
6、imensional shape is placed in a holder.A guide or pointer then moves along this shape and its movement controls that of the cutting tool.The duplication may include a square or tapered shoulder，grooves，tapers，and contours.Work such as motor shafts，spindles，pistons，rods，car axles，turbine shafts，and a
7、 variety of other objects can be turned by using this type of lathe.Text&Translationl3.Turret LatheslWhen machining a complex workpiece on a general purpose lathe，a great deal of time will be spent in changing or adjusting the tools needed.2One of the first adaptations of the engine lathe which made
8、 it more suitable to mass production was the addition of multi tool turret in place of the tailstock.Although most turrets have six stations，some have as many as eight.lHigh production turret lathes are very complicated with many power accessories.The principal feature of all turret lathes，however，i
9、s that they can perform a consecutive serial of operations in proper sequence.Once the tools have been set and adjusted，little skill is required to turn out duplicate parts.Text&Translationl4.Automatic Screw Machinesl3Screw machines are similar in construction to turret lathes，except that their head
10、s are designed to hold and feed long bars of stock.Otherwise，there is little difference between them.Both are designed for multiple tooling，and both have adaptations for identical work.4Originally，the turret lathe was designed as a chucking lathe for machining small castings，forgings，and irregularly
11、 shaped workpieces.Text&TranslationlThe first screw machines were designed to feed bar stock and wire used in making small screw parts.At present，however，the turret lathe is frequently used with a collet attachment，and the automatic screw machine can be equipped with a chuck to hold castings.lThe si
12、ngle spindle automatic screw machine，as its name implies，machines work on only one bar of stock at a time.A bar 16 to 20 feet long is fed through the headstock spindle and is held firmly by a collet.The machining operations are done by cutting tools mounted on the turret and on the cross slide.When
13、the machine is in operation，the spindle and the stock are rotated at selected speeds for different operations.Rapid reversal of spindle direction can also be achieved if necessary.Text&TranslationlIn the single spindle automatic screw machine，a specific length of stock is automatically fed through t
14、he spindle to a machining area.At this point，the turret and cross slide move into position and automatically perform whatever operations are required.After the machined piece is cut off，stock is again fed into the machining area and the entire cycle is repeated.Text&Translationl5Multiple spindle aut
15、omatic screw machines have from four to eight spindles located around a spindle carrier.Long bars of stock，supported at the rear of the machine，pass through these hollow spindles and are gripped by collets.With the single spindle machine，the turret indexes around the spindle.When one tool on the tur
16、ret is working，the others are not.With a multiple spindle machine，however，the spindle itself indexes.Thus the bars of stock are carried to the various end working and side working tools.Each tool operates in only one position，but all tools operate simultaneously.Consequently，four to eight workpieces
17、 can be machined at the same time.Text&Translationl5.Vertical Turret LatheslA vertical turret lathe is basically a turret lathe that has been stood on its headstock end.It is designed to perform a variety of turning operations.It is made up of a turret，a revolving table，and a side head with a square
18、 turret for holding additional tools.Operations performed by any of the tools mounted on the turret or side head can be controlled through the use of stops.Text&Translationl6.Machining CenterslMany sophisticated lathes are now called machining centers because they can perform certain milling and dri
19、lling operations in addition to the ordinary turning operations.Basically，a machining center is a combination of a turret lathe and a milling machine.Manufacturers sometimes add additional features to the machining center in order to increase its versatility.Text&Translationl车床在工业生产中被广泛用来加工各种类型的机械零件
20、。一些车床是通用机床，而另一些车床则被用来完成某些专门工序的加工任务。l1.普通车床普通车床l普通车床是全世界的生产车间和维修车间里广泛使用的通用机床。它的尺寸范围很广，从小型的台式车床到巨大的重型车床。许多大型的车床配备在普通车间中通常看不到的附件，例如，溜板的自动挡块。Text&Translationl2.靠模车床或仿形车床靠模车床或仿形车床l靠模车床或仿形车床被设计用来对形状不规则的零件进行自动加工。这种车床的基本操作如下：在加持装置上安装平面或立体形状的样板，然后，导向触头或指针沿着它的外形移动，从而控制切削刀具的运动。仿形加工可以包括方形或锥形轴肩、各种槽、椎体和轮廓。像电动机的轴、
21、主轴、活塞、杆件、汽车轴、汽轮机轴和其他很多种类的工件都可以采用这种车床来进行切削加工。Text&Translationl3.转塔车床转塔车床l在通用车床上加工一个复杂的工件时，在更换和调整加工时所用的一些刀具上要花费很多时间。对普通车床的早期改装工作之一是增加一个可以安装多把刀具的转塔来代替尾架，使它能够更好地适应大批量生产的需要。虽然大多数转塔有六个工位，但有些转塔有八个工位。l高生产率的转塔车床是装有许多动力附件的非常复杂的机器。然而，所有转塔车床的主要特点是刀具能按适当顺序完成一系列的加工工序。一旦这些刀具被安装调整好后，只需要很低的技术就可车削加工很多相同的零件。Text&Trans
22、lationl4.自动螺丝车床自动螺丝车床l螺丝车床在结构上与转塔车床类似，不同之处是螺丝车床的主轴头部能被设计成用来夹持和送进长棒料。除此之外，它们之间几乎没有什么差别。这两种车床都用于多刀具切削，都适合加工同样的工件。最初，为转塔车床设计的用途和卡盘车床的用途一样，也是用来加工小型铸件、锻件和形状不规则的零件。l早期的螺丝车床通过棒料和线材的送进，制造小的螺丝零件。时至今日，转塔车床上经常使用夹头附件，而自动螺丝车床上则可通过安装卡盘用来夹持铸件。Text&Translationl单轴自动螺丝车床，顾名思义，一次只能加工一根棒料。一根16至20英尺（488610 cm）长的棒料可以通过主轴
23、箱中的主轴孔送进，并用夹头将其加紧。机械加工工序是由装在转塔和横刀架上的刀具完成的。当机床工作时，主轴和棒料按照为每道工序所选择的转速旋转。如果需要时也可以使主轴快速反转。l在单轴自动螺丝车床上，棒料的一段规定好的长度穿过主轴自动送到加工区。在这里，转塔和横向刀架进入加工位置并自动完成所需的任何加工工作。当加工好的零件被切断后，棒料再次被送入加工区，并重复整个循环。Text&Translationl多轴自动螺丝车床在主轴鼓周围装有48根主轴。在机床尾部支撑着的长棒料穿过这些空心的主轴，其他的刀具不工作。然而，在多轴自动车床上，主轴自己转位。因此，几根棒料被转位到各个不同的端面加工和侧面加工的刀
24、具位置处。每把刀具仅在一个位置工作，但是所有的刀具都能同时工作。因此，能够在同一时间内加工48个工件。Text&Translationl5.立式转塔车床立式转塔车床l立式转塔车床基本上就是将其从床头箱一端向下而竖立起来的一台转塔车床。它被设计用来完成各种的切削工作。它由一个转塔，一个旋转工作台和一个侧面溜板组成的。在侧面溜板上装有可以再安装几把刀具的正方形刀架。由安装在转塔或侧面溜板上的任何刀具完成的加工工序都可通过使用挡块来加以控制。Text&Translationl6.加工中心加工中心l当前，许多技术更为先进的车床叫做加工中心。因为，它们除了完成常规的车削工作之外，还可以完成某些铣削、钻削
25、工作。加工中心基本上可以认为是转塔车床和铣床的组合体。有时，制造厂商为了增加机床的多用性，还会增加一些其他的性能。Complex Sentence Analysisl1 Engine lathes,of course,are general-purpose machines used in production and maintenance shops all over the world.普通车床是全世界的生产车间和维修车间里广泛使用的通用机床。l general-purpose：多方面的，多用途的l maintenance shops：维修车间Complex Sentence Analy
26、sisl2 One of the first adaptations of the engine lathe which made it more suitable to mass production was the addition of multi-tool turret in place of the tailstock.对普通车床的早期改装工作之一是增加一个可以安装多把刀具的转塔来代替尾座，使它能够更好地适应大批量生产的需要。l first adaptations：早期改装工作l in place of：代替，而不是Complex Sentence Analysisl3 Screw
27、machines are similar in construction to turret lathes,except that their heads are designed to hold and feed long bars of stock.螺纹车床在结构上与转塔车床类似，不同之处是螺丝车床的主轴头部能被设计用来夹持和送进长棒料。l in construction：介词短语，表示“在结构上”。l except 在此为介词，其后接的是由that引导的宾语从句，bar of stock和bar stock都指棒料。Complex Sentence Analysisl4 Original
28、ly,the turret lathe was designed as a chucking lathe for machining small castings,forgings,and irregularly shaped workpieces.最初，为转塔车床设计的用途和卡盘车床的用途一样，也是用来加工小型铸件、锻件和形状不规则的零件。l chucking lathe：卡盘车床，指床身较短，无尾座的卧式车床。l machine：此处为动词，意为：用机器做，加工。Complex Sentence Analysisl5 Multiple-spindle automatic screw mac
29、hines have from four to eight spindles located around a spindle carrier.多轴自动螺丝车床在主轴鼓周围装有4到8根主轴。lspindle carrier：主轴鼓，指内装若干根主轴，并能转位、定位的鼓轮部件。Key to ExerciseslI.Translationl普通车床 l2.maintenance shop l3.自动挡块 l4.duplicating lathes l5.转塔车床 lpower accessory l7.自动螺丝车床 l8.chucking lathe l9.夹头附件 l10.side headKe
30、y to ExerciseslII.True or Falsel1.F l2.F l3.F l4.T l5.TKey to ExerciseslIII.Blank Fillinglautomatically l2.machining area l3.spindle carrier l4.bars of stock l5.side working tools l6.simultaneouslyKey to ExerciseslIV.Chinese to EnglishlMany of the larger lathes come equipped with attachments not commonly found in the ordinary shoplWhen machining a complex workpiece on a general-purpose lathelmachining small castings,forgingslperform a variety of turning operationslincrease the versatility of their machineslThe end!
