专业英语PPT演讲稿_高一英语演讲稿

专业英语PPT演讲稿由刀豆文库小编整理，希望给你工作、学习、生活带来方便，猜你可能喜欢“高一英语演讲稿”。

1、Lathe [leið]

2、Value of two yuan of the third series of the RMB ——the turner3、A lathe is a machine tool which rotates the workpiece on its axis to perform various ['vεəriəs] operations such as cutting, sanding(砂磨), knurling['nə:liŋ](滚花), drilling, or deformation with tools that are applied to the workpiece to create an object which has symmetry['simitri](对称)about an axis of rotation.（center lathe，vertical lathe）

4、History

The lathe is an ancient tool, dating at least to ancient Egypt ['i:dʒipt] and known and used in Ayria [ə'siriə] and ancient Greece [ɡri:s].The origin ['ɔridʒin, 'ɔ:-] of turning dates to around 1300 BC when the Ancient ['einʃənt] Egyptians [i:'dʒipʃənz] first developed a two-person lathe.（One person would turn the wood work piece with a rope while the other used a sharp tool to cut shapes in the wood.）Ancient Rome improved the Egyptian design with the addition of a turning bow.In the Middle Ages a pedal replaced hand-operated turning,（freeing both the craftsman's hands to hold the woodturning tools.The pedal was usually connected to a pole, often a straight-grained sapling.）The system today is called the “spring pole” lathe.Spring pole lathes were in common use into the early 20th century.During the Industrial Revolution, mechanized ['mekənaizd] power generated by water wheels or steam engines was transmitted to the lathe via line shafting,(allowing faster and easier work.Metalworking lathes evolved into heavier machines with thicker, more rigid parts.)Between the late 19th and mid-20th centuries, individual electric motors ['məutə] at each lathe replaced line shafting as the power source.Beginning in the 1950s, servomechanism[,sə:vəu'mekənizəm, 'sə:vəu,me-](伺服机构)were applied to the control of lathes and other machine tools via numerical control,(which often was coupled with computers to yield computerized numerical control.)Today manually controlled and CNC lathes coexist（共存）in the manufacturing industries ['indəstri].5、Description：Parts

Explanation of the standard components of most lathes:

• Bed床身: Usually made of cast iron.Provides a heavy rigid frame on which all the main components are mounted.• Ways床身导轨: Inner and outer guide rails that are precision machined parallel to aure accuracy of movement.• Headstock['hedstɔk]床头箱，主轴箱: mounted in a fixed position on the inner ways, usually at the left end.Using a chuck, it rotates the work.• Gearbox ①齿轮箱②变速器: inside the headstock, providing multiple speeds with

a geometric ratio by moving levers.• Spindle['spindl]心轴，主轴: Hole through the headstock to which bar stock can be fed, which allows shafts that are up to 2 times the length between lathe centers to be worked on one end at a time.• Chuck卡盘: 3-jaw(self centering)or 4-jaw(independent)to clamp part being machined.• Chuck: allows the mounting of difficult workpieces that are not round, square or triangular.• Tailstock尾架: Fits on the inner ways of the bed and can slide towards any position the headstock to fit the length of the work piece.An optional taper turning attachment would be mounted to it.• Tailstock Quill[kwil]尾架套管: Has a Morse taper to hold a lathe center, drill bit or other tool.• Carriage托架，滑动架: Moves on the outer ways.Used for mounting and moving most the cutting tools.• Cro Slide横刀架，横拖板，横溜板: Mounted on the traverse slide of the carriage, and uses a handwheel to feed tools into the workpiece.• Tool Post刀架，刀座: To mount tool holders in which the cutting bits are clamped.• Compound Rest复式刀架: Mounted to the cro slide, it pivots around the tool post.• Apron['eiprən]床鞍: Attached to the front of the carriage, it has the mechanism and controls for moving the carriage and cro slide.• Feed Rod进给杆: Has a keyway, with two reversing pinion gears, either of which can be meshed with the mating bevel gear to forward or reverse the carriage using a clutch.• Lead Screw丝杠: For cutting threads.• Split Nut开合螺母: When closed around the lead screw, the carriage is driven along by direct drive without using a clutch.• Quick Change Gearbox快换齿轮箱: Controls the movement of the carriage using levers.• Steady Rest固定中心架: Clamped to the lathe ways, it uses adjustable fingers to contact the workpiece and align it.Can be used in place of tailstock or in the middle to support long or unstable parts being machined.• Follow Rest跟刀架: Bolted to the lathe carriage, it uses adjustable fingers to bear against the workpiece opposite the cutting tool to prevent deflection.6~

9、Description：acceories [ək'sesəri]

three-jaw [dʒɔ:] chuck [tʃʌk]: Self-centering three-jaw chuck and key with one jaw removed and inverted showing the teeth that engage in the scroll plate.The scroll plate is rotated within the chuck body by the key, the scroll engages the teeth on the underside of the jaws which moves the three jaws in unison, to tighten or release the workpiece.four-jaw chuck :Independent four-jaw chuck, also known as a universal chuck, with the jaws independently set.The key is used to adjust each jaw separately.Collet弹性夹头: A collet ['kɔlit] is a holding device—specifically, a subtype of chuck—that forms a collar around the object to be held and exerts a strong clamping force on the object when it is tightened, usually by means of a tapered outer collar.It may be used to hold a workpiece or a tool.Faceplate花盘: A lathe faceplate is the basic workholding acceory for a wood or metal turning lathe.It is a circular metal(usually cast iron)plate which fixes to the end of the lathe spindle.The workpiece is then clamped to the faceplate, typically using t-nuts in slots in the faceplate, or le commonly threaded holes in the faceplate itself.dead center死顶尖: Dead center(The conical piece)mounted in the spindle of a lathe and being used to support a workpiece being driven by a carrier setup live center活顶尖:A live center or revolving center is constructed so that the 60° center runs in its own bearings and is used at the non-driven or tailstock end of a machine.[2] It allows higher turning speeds without the need for separate lubrication [,lu:bri'keiʃən], and also greater clamping preures.lathe carrier['kæriə]车床鸡心夹头: A lathe dog, also known as a lathe carrier, is a device that clamps around the workpiece and allows the rotary motion of the machine's spindle to be transmitted to the workpiece.Mandrel['mændrəl]心轴: an object used to shape machined work.10、application

Lathes are used in woodturning, metalworking, metal spinning（旋压）, and gla-working.Lathes can be used to shape pottery, the best-known design being the potter's wheel陶车.Most suitably equipped metalworking lathes can also be used to produce most solids of revolution, plane surfaces and screw threads or helices.Ornamental [,ɔ:nə'mentəl] lathes can produce three-dimensional solids（实体）of incredible complexity11、Examples of work produced from a lathe12、thank you!

I`m very happy to have this opptunity to give you a talk.today,my topic is lathe.I know many of you are familiar with this topic

Can you hear me clearly?

I think ti would be best to start out by looking at the picture on the screen

I would like to talk about first is the definition of the lathe

question ['kwestʃən]

that is all,thank you very much

do you have any questions? please show me your hand.Who else?

I think we have time for just one more question