机床-工艺夹具毕业课程设计外文文献翻译、中英文翻译

目录1 英文文献翻译11.1 Machine Tools11.2 机 床92 专业阅读书目162.1 机械设计162.2 机械原理162.3 材料力学172.4 现代工程图学172.5 互换性与技术测量182.6 机电传动控制182.7 机械制造基础182.8 机械制造技术192.9 数控技术192.10 理论力学201 英文文献翻译1.1 Machine ToolsMachine Tools are machines for cutting metals.The most important of machine tools used in industry are lathes,drilling machines and milling machines.Other kinds of metal working machines are not so widely used in machining metals as these three.The lathe is commonly called the father of the entire machine tool family.For turning operations,the lathe uses a single point cutting tool,which removes metal as it travels past the revolving work-piece.Turning operations are required to make many different cylindrical shapes,such as axes,gear blanks,pulleys,and threaded shafts.Boring operations are performed to enlarge,finish,and accurately locate holes.Drilling is performed with a rotating tool called a drill.Most drilling in metal is done with a twist drill.The machine used for drilling is called a drill press.Operations,such as reaming and tapping,are also classified as drilling.Reaming consists of removing a small amount of metal form a hole already drilled.Tapping is the process of cutting a thread inside a hole so that a cap screw or bolt may be threaded into it.Milling removes metal with a revolving,multiple cutting edge tools called milling cutter.Milling cutters are made in many styles and size.Some have as few as two cutting edges and others have 30 or more.Milling can produce flat,angled surfaces,groves,slots,gear teeth,and other profiles,depending on the shape of the cutters being used.Shaping and planing produce flat surfaces with a single point cutting tool.In shaping,the cutting tool on a shaper reciprocates or moves back and forth while10the work is fed automatically towards the tool.In planing,the work-piece is attached to a worktable that reciprocates past the cutting tool.The cutting tool is automatically fed into the work-piece a small amount on each stroke.Grinding makes use of abrasive particles to do the cutting.Grinding operations may be classified as precision or non-precision,depending on the purpose.Precision grinding is concerned with grinding to close tolerances and very smooth finish.Non-precision grinding involves the removals of metal where accuracy is not important.LatheA lathe is a machine tool for cutting metal form the surface of a round work fastened between the two lathe centers and turning around its axis.In turning the work a cutter moves in the direction parallel to the axis of rotation of the work or at an angle to this axis,cutting off the metal from the surface of the work.This movement of the cutter is called the feed.The cutter is clamped in the tool post which is mounted on the carriage.The carriage is the mechanism feeding the cutter in the needed direction.The lathe hand may feed the cutter by hang or may make it be fed automatically by means of special gears.The largest part of the lathe is called the bed on which the headstock and the tailstock are fastened at opposite ends.On the upper part of the bed there are special ways upon which the carriage and the tailstock silde.The two lathe centers are mounted in two spindles:one(the live center)is held in the headstock spindle,while the other (the dead center)in the tailstock spindle.The lathe chuck is used for chucking the work,which is for clamping it so that it will rotate without wobbling while turning.The chuck,usually,mounted on the headstock spindle,may have different sizes and construction.If the work is perfectly round,it may be chucked in the so-called three-jaw universal chuck,all the jaws of which are moved to the center by turning the screw.But if the work is not perfectly round,the four-jaw independent chuck should be used.In turning different materials and works of different diameters,lathes mustbe run at different speeds.The gearbox contained in the headstock makes it possible to run the lathe at various speeds.Before turning a work in the lathe,the lathe centers are to be aligned;that means that the axes of both centers must be on one line.The alignment of the lathe center may be tested by taking a cut and then measuring both ends of the cut with a micrometer,Not all works should be fastened between the two centers of the lathe.A short work may be turned without using the dead center,by simply chucking it properly at the spindle of the headstock.Drills and Drilling MachinesThe twist drill is a very efficient tool.It is generally formed by forging and twisting grooves in a flat strip of steel or by milling a cylindrical piece of steel,high-speed steel being commonly used.High-speed steel costs more but tools made of it withstand heat much better than those made of ordinary tool steel.The twist drill may be divided into three principal parts:body,shank,and point.The flutes are the spiral grooves that are formed on the side of a drill,drills being made with two,three,or four flutes.Those having three or four flutes are used for following smaller drills or for enlarging holes already drilled,and are not suited for drilling into solid stock.Spiral flutes have four main advantages:(1) They give the correct rake to the lip of a drill.(2) They cause the chip to curl so tightly that it occupies the minimum amount of space.(3) They form channels through which chips escape from the hole.(4) They allow the lubricant to flow easily down to the cutting edge.The margin is the narrow strip on the cutting edge of the flute.It is practically the full diameter of the drill and extends the entire length of the flute,its surface being a part of a cylinder.The portion of the body next tothe margin is of less diameter than the margin.This lessened diameter,called body clearance,reduces the friction between the drill and the walls of the hole,while the margin insures the hole being of accurate size.The shank is the end of the drill which fits into the socket,spindle,or chuck of the drill press.The tang is usually found only on tapered shank tools.The drilling machine is the second oldest machine tools,having been invented shortly after the lathe,and is one of the most common and useful machines.The drilling machines may be classified into three general types:vertical spindle,multiple spindle,and radial spindle machine.The vertical spindle drilling machine comes in three types:heavy duty,plain,and sensitive.Besides the drilling of holes,such operations may be performed on the drilling machine:drilling,tapping(internal threading),reaming(finishing the hole with a reamer),countersinking,counterboring,boring and spot-facing.Milling MachinesThe milling machine is a machine that removes metal from the work with a revolving milling cutter as the work is fed against it.The milling cutter is mounted on an arbor where it is held in place by spacers or bushing.The arbor is fixed in the spindle with one end,while the other end of the arbor rotates in the bearing mounted on the arbor yoke.The milling cutter are generally made from high speed steel and are available in different sizes and shapes.There are such kinds of milling cutters as cylindrical cutters,end milling cutters(for face milling),from milling cutters,angular,side and face cutter,slitting saw,ect.These cutters may differ in the direction of their operation,i.e.they may cut revolving either clockwise or counter-clockwise.Regular or irregular shaped work may be produced on a milling machine,designs varying according to the particular class of work wanted.According to the position of the spindle,the milling machines may be divided into two groups of vertical spindle milling machines and horizontal spindle millingmachines.Milling machines may be grouped into various classes.According to the variation in general design as thecolumn and knee type,the manufacturing types,and the planner type of milling machine.According to the table design,the milling machines may be classified as universal and plain milling machines.The most important parts of the milling machine are starting levers,spindle,column,knee,elevating screw,table,index head,speed levers,feed movement,table movement levers,foot stock,arbor yoke.The spindle of the milling machine is driven by an electric motor through a train of gears mounted in the column.The table of the plain milling machine may travel only at right angles to the spindle,while the universal milling machine is provided with a table that may be swiveled on the transverse slide for milling gear teeth,threads,ect.Various attachments are used for increasing the range of work that can be performed on a milling machine.The dividing head(also called an index head)is a device used to divide the periphery of a piece of work into any number of equal parts,and to hold the work in the required position while the cuts are being made.Various kinds of vises may be used for holding the work in a milling machine,the most common being the plain vise,and the swivel vise.ThePlanerThe planer is one of the biggest machine tools that employ a reciprocating cutting action.It generates flat or contoured surfaces in a series of straight cuts.Its efficiency is higher than that of the shaper.The work on the planer is held on the machine table and moves under the tool which is carried on the rail.The bed must be approximately twice as long as the table to support it at all positions during the stroke.The double-housing on one side only.Open-side planers are designed for work-pieces which are so wide that they can pass between the housings of double-housing planers.Thedouble-housing machine,however,offers greater rigidity.Some of the work that was formerly done on the planer is now done on the planer-type milling machine since the former is not so efficient as the latter.However,there are still many jobs that can be carried out better and more economically on the planer than on any other machines.For example,angular surfaces are often easier to machine on a planer.Planning is also most effective in the machining of long and narrow surfaces.In addition,the planer usually takes the important first cut on the rough forging or casting to establish a reference surface for subsequent machining.GrindingMachinesGrinding,or abrasive machine,is one of the most rapidly growing metal removal processes in manufacturing.Many machining operations,previously done on conventional milling machines,lathes and shapers,are now performed on various types of grinding machines.There is a great variety of grinding machines.The machines that are generally used are cutter grinder,surface grinder,centerless grinder,external grinder,internal grinder,and tool grinder.Five types of grinding operations are performed on grinding machines:（1）Surface grinding.Surface grinding are used to produce flat,angular and irregular surfaces.In the surface grinding process,the grinding wheel revolves on a spindle;and the workpiece,mounted on either a reciprocating or a rotary table,is brought into contact with the grinding wheel.（2）Cylindrical grinding.Cylindrical grinding is the process of grinding the outside surface of a cylinder.These surfaces may be straight,tapered or contoured.Cylindrical grinding operations resemble lathe turning operations.They replace the lathe when the workpiece is hardened or when extreme accuracy and superior finish are required.As the workpiece revolves,the grinding wheel,rotating much faster in the opposite direction,is brought into contactwith the part.The workpiece and table reciprocate while in contact with the grinding wheel to remove material.（3）Centerless grinding.Centerless grinding machines eliminate the need to have center holes for the work or to use workholding devices.In centerless grinding,the workpiece rests on a workrest blade and is backed up by a second wheel,called the regulating wheel.The rotation of the grinding wheel pushes the workpiece down on the workrest blade and against the regulating wheel.The regulating wheel,usually made of a rubber bonded abrasive,rotates in the same direction as the grinding wheel and controls the longitudinal feed of the work when set at a slight angle.By changing this angle and the speed of the wheel,the workpiece feed rate can be changed.（4）Internal grinding.Internal grinders are used to accurately finish straight,tapered or formed holes.The most popular internal grinder is similar in operation to a boring operation in a lathe.The work-piece is held by a workholding device,usually a chuck or collet,and revolved by a motorized headstock.A separate motor head in the same direction as the workpiece revolves the grinding wheel.It can be fed in and out of the work and also adjusted for depth of cut.（5）Special grinding processes.Special types of grinders are grinding machines made for specific types of work and operations.A brief description of the more commonly used special types follows:Tool and cutter grinders:There grinding machines are designed to sharpen milling cutters,reamers,taps and other machine tool cutters.The general purpose cutter grinder is the most popular and versatile tool grinding machine.Various attachments are available for sharpening most types of cutting tools.Jig grinding machines:Jig grinders were developed to locate and accurately grind tapered or straight holes.Jig grinders are equipped with a high speed vertical spindle for holding and driving the grinding wheel.They utilize the same precision locating system as do jig borers.Thread grinding machines:These are special grinders that resemble the cylindrical grinder.They must have a precision lead screw to produce the correct pitch,or lead,on a threaded part.Thread grinding machines also have a means of dressing or truing the cutting periphery of the grinding wheel so that it will produce a precise thread form on the part.Boring MachineBoring,also called internal turning,is used to increase the inside diameter of a hole.The original hole is made with a drill,or it may be a cored hole in a casting.Boring achieves three things:Sizing:Boring brings the hole to the proper size and finish. Straightness:Boring will straighten the original drilled or cast hole.Concentricity:Boring will make the hole concentric with the outside diameter within the limits of the accuracy of the chuck or holding device.The boring operation is generally performed in two steps;namely,rough boring and finish boring.The objective of the rough-boring operation is to remove the excess metal rapidly and efficiently,and the objective of the finish boring operation is to obtain the desired size,surface finish,and location of the hole .The size of the hole is obtained by using the trial-cut procedure.The diameter of the hole can be measured with inside calipers and outside micrometer calipers.Basic Measuring Instruments,or inside micrometer calipers can be used to measure the diameter directly.Shoulders,grooves,contours,taper,and threads are also bored inside of holes.Internal grooves are cut using a tool that is similar to an external grooving tool.The procedure for boring internal shoulders is very similar to the procedure for turning shoulders.Large shoulders are faced with the boring tool positioned with the nose leading,and using the cross slide to feed the tool.Internal contours can be machined using a tracing attachment on a lathe.The tracing attachment is mounted on the cross slide and the stylus follows the outline of the master profile plate.This caused the cutting tool to move in apath corresponding to the profile of the master profile plate.Thus,the profile on the master profile plate is reproduced inside the bore.The master profile plate is accurately mounted on a special slide which can be precisely adjusted in two directions,in order to align the cutting tool in the correct relationship to the work.Normal turning cuts are taken with the spindle rotating counterclockwise.The boring cut is taken with the spindle revolving in a clockwise direction,or backwards.1.2 机 床机床是用于切削金属的机器。工业上使用的机床要数车床、钻床和铣床最为重要。 其它类型的金属切削机床在金属切削加工方面不及这三种机床应用广泛。车床通常被称为所有类型机床的始祖。为了进行车削，当工件旋转经过刀具时，车 床用一把单刃刀具切除金属。用车削可以加工各种圆柱型的工件，如：轴、齿轮坯、皮 带轮和丝杠轴。镗削加工可以用来扩大和精加工定位精度很高的孔。钻削是由旋转的钻头完成的。大多数金属的钻削由麻花钻来完成。用来进行钻削加 工的机床称为钻床。铰孔和攻螺纹也归类为钻削过程。铰孔是从已经钻好的孔上再切除 少量的金属。攻螺纹是在内孔上加工出螺纹，以使螺钉或螺栓旋进孔内。 铣削由旋转的、多切削刃的铣刀来完成。铣刀有多种类型和尺寸。有些铣刀只有两个切削刃，而有些则有多达三十或更多的切削刃。铣刀根据使用的刀具不同能加工平面、 斜面、沟槽、齿轮轮齿和其它外形轮廓。牛头刨床和龙门刨床用单刃刀具来加工平面。用牛头刨床进行加工时，刀具在机床 上往复运动，而工件朝向刀具自动进给。在用龙门刨床进行加工时，工件安装在工作台 上，工作台往复经过刀具而切除金属。工作台每完成一个行程刀具自动向工件进给一个 小的进给量。磨削利用磨粒来完成切削工作。根据加工要求，磨削可分为精密磨削和非精密磨削。 精密磨削用于公差小和非常光洁的表面，非精密磨削用于在精度要求不高的地方切除多 余的金属。车 床车床是用来从圆形工件表面切除金属的机床，工件安装在车床的两个顶尖之间，并 绕顶尖轴线旋转。车削工件时，车刀沿着工件的旋转轴线平行移动或与工件的旋转轴线 成一斜角移动，将工件表面的金属切除。车刀的这种位移称为进给。车刀装夹在刀架上， 刀架则固定在溜板上。溜板是使刀具沿所需方向进行进给的机构。用于操纵车床手柄可 使车刀实现进给，也可以借助专门的传动装置实现自动进给。车床的最大部件称为床身，它的两端分别装有床头箱和尾座。床身表面有专门的导 轨，溜板和尾座可以在导轨上滑行。车床的两个顶尖分别装在两根主轴中：活顶尖装在床头箱主轴中，另一个死顶尖则 装在尾座的主轴中。车床卡盘用于夹紧工件，其目的在于使工件在车削时不摇晃。通常，安装在床头箱 主轴上的卡盘可具有不同的尺寸和结构。如果工件是一完整的圆，可将其夹紧在所谓的 三爪通用卡盘中，卡盘的三个爪靠转动螺旋机构能同时向中间移动。但是如果工件系非 完整的圆，则应使用四爪相互独立的四爪卡盘。车床在车削不同材料和不同直径的工件时，必须以不同的速度运转。装在床头箱内 的齿轮系统能使车床以不同的速度运转。车床在车削工件前，它的顶尖要对准，即两个顶尖的轴线必须在同一直线上。 为检验车床顶尖的同轴度，可进行一次车削，然后用千分尺测量车削物的两端。13并非所有的工件都必须装夹在车床的两个顶尖之间。短工件的车削可不使用死顶 尖，而是简单的将其适当夹紧在床头箱的主轴上。钻 头 和 钻 床麻花钻头是一种高效率的刀具，它通常由扁钢锻造后扭转出凹槽，或由圆柱棒料铣削而成，一般用高速钢制作。高速钢的成本虽然较高，但用它制作的刀具在耐热 性方面要比用普通工具钢制作的刀具好得多。麻花钻可分做三个主要部分：钻体、钻柄和钻尖。螺旋槽是位于钻头侧面的螺旋形 凹槽，钻头制成两条、三条或四条螺旋槽。带有三条或四条螺旋槽的钻头用于较小钻头 钻孔后继续钻孔的场合，或对已钻好的孔进行扩孔，而不宜在实体坯料上钻孔。螺旋槽主要有四个好处：（1）螺旋槽使钻头的切削刃有正确的前角；（2）螺旋槽可以卷紧切屑，使其占有最小的空间；（3）螺旋槽可以构成若干通道，切屑能借助这些通道从孔内排出；（4）螺旋槽可以使润滑剂顺利地流向切削刃。 刃带（棱边）是螺旋槽切削刃上的狭带。刃带部分实际上是钻头的最大直径处，它伸展到螺旋槽的全长，它的表面是圆柱体的一部分。紧靠刃带的钻体部分其直径略小于 刃带的直径，减小的直径称做钻体间隙。钻体间隙用来减少钻头和孔壁间的摩檫，而刃 带则用来保证孔的准确尺寸。钻头的一端是钻柄，它被安装在钻套、钻床的主轴或钻夹头中。通常只有锥柄钻头