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机械工程专业英语作业及期末复习作业一1.Most machining has very low set-up cost compared with forming, molding, and casting processes. However, machining is much more expensive for high volumes. 译文:与成型加工、锻压和铸造工艺相比,大多数机械加工的生产准备成本都较低,然而如果是大批量生产,其成本要高得多。2. Turning can occur on both external and internal surfaces to produce an axially-symmetrical contoured part.译文:车削可以加工外面和内表面以形成具有轴对称的成形工件。3. Facing is the producing of a flat surface as the result of a tools being fed across the end of the rotating workpiece. 译文:车端面可以加工出一个平面,它是当车刀沿回转工件的端面横向进给的结果。4. Threading can be considered as turning since the path to be travelled by the cutting tool is helical.译文: 车螺纹可以看作是车削,只是车刀所形成的加工轨迹是螺旋线。5. many types of lathes are used for production turning . According to purposes and construction ,lathe-type machine tools can be classified as follows: 译文:许多种类的车床都可以用于车削,根据它的目的和结构,车床可以分为以下几种类型。1. Engine lathes 普通车床 2. Vertical lathes 立式车床 3. Turret lathes 转塔车床4. Single-or mulitple-spindle automatic or semi-automatic lathes 单或多轴自动或半自动车床5. Contouring lathes 仿形车床 6. Universal lathes 万能车床7. Special-purpose lathes such as crankshaft lathes camshaft lathes ,car wheel lathes and backing-off lathes,etc专用车床,如曲轴车床、凸轮轴车床、汽车车轮车床、铲齿车床等作业二1. Quality and accuracy are major considerations in making machine parts or structures.Interchangeable parts require a high degree of accuracy to fit together.译文:在制造机器零件和结构的过程中,质量和精度是最重要的因素。互换性零件需要有高精度以实现相互配合.2. Deviations of actual surfaces are divided into four groups to enable assessment, prescription and checking of the permitted inaccuracy during production: 译文:实际加工表面的偏差在进行评估说明和允许误差的检查过程中被分为四类1. Dimensional deviations; 1尺寸偏差;2. Shape deviations; 2形状的偏差;3. Position deviations; 3位置偏差;4. Surface roughness deviations. 4表面粗糙度的偏差。3. Unnecessarily tight tolerances lead to high cost of manufacture resulting from more expensive manufacturing methods and higher reject rates. 译文:不必要的紧公差会导致由于昂贵的制造方法和较高的废品率所带来的高的制造成本。4. Transition fit. It is a fit where (depending on the actual sizes of the hole and shaft) both clearance and interference may occur in the coupling. Tolerance zones of the hole and shaft partly or completely interfere. 译文:过渡配合。这是一个适合在那里(根据实际大小的孔和轴)的间隙和干扰可能会出现在耦合。孔和轴公差带部分或完全干涉。过渡配合。这是一个符合(取决于实际大小的孔、轴)两个间隙和干扰可能发生耦合。公差带的孔、轴部分或完全干涉过渡配合是(根据实际大小的孔和轴)间隙和过盈在配合时都会发生的一种配合。孔和轴的公差带会部分或完全覆盖。作业三1. To ensure that the workpiece is produced according to the specified shape, dimensions and tolerances, it is essential that workplace should be appropriately located and clamped on the machine tool.译文:为了确保按照规定的形状,尺寸和公差将工件加工出来,至关重要的一点就是要将工件恰当地定位并夹紧在机床上。2. Interchangeability. Jigs and futures facilitate uniform quality in manufacture. There is no need for selective assembly. Any part of machine fits properly in assembly and all similar components are interchangeable 。3. Another condition to avoid in workholder design is redundant or duplicate location. Redundant locators restrict the same degree of freedom more than once. 译文:另一种情况下,在工装夹具设计是多余的或重复的位置,避免。冗余定位限制相同的自由度超过一次。4. Clamping device ,however ,is used to ensure that the fixture ,workpiece and location features will not be distorted or damaged under the action of cutting forces ,gravity ,inertial force and centrifugal force etc . 译文作业四1. The gear that supplies the power is called the input gear and the gear that does the actual work at the other end of the gear drive is the output gear. 译文:2. The tooth form is based on the involute curve shown in Fig.9.1. Practice has shown that this design accommodates mostly rolling rather than sliding contact of the tooth surfaces.译文:齿形是基于渐开线曲线如图9.1所示。经验表明,这种设计可以很好的适应齿面的滚动接触,而不是滑动接触。3. These rapid shocks result in some objectionable operating noise and vibration.译文:快速冲击可以导致不良的工作噪音和振动。4. Also, several teeth are in contact at any one time, producing a more gradual loading of the teeth that reduces wear substantially. 译文:作业五1. An important distinction applied to control systems, whether automatic or otherwise, is that between open-loop and closed-loop operation. 译文:控制系统的一个重要区别,无论是自动还是其他,都是开环和闭环操作之间的一个重要区别。2. In this form of control, the valve is adjusted to make output c equal to input r, but not readjusted continually to keep the two equal.译文:在这个控制阀调节中,使输出C等于输入R,但不能连续保持两个相等。3. The feedback loop causes the system to take corrective action if output c (actual level) deviates from input r (desired level), whatever the reason。译文:反馈回路使系统采取纠正措施,如果输出(实际水平)偏离输入(期望水平),无论是什么原因。4. Therefore, it is quite inadequate to operate an actuator. A task of the controller is to amplify the error signal. The power amplifier raises power to the levels needed for the actuator. 译文:因此,操作一个执行器是相当不充分的。控制器的任务是放大误差信号。功率放大器提高了执行器所需的功率。械工程专业英语期末复习单词Planes斜面levers杠杆gears齿轮cams凸轮cranks曲柄springs弹簧belts皮带wheels滚轮axles轮轴pulleys滑轮screws螺钉element元素wrench扳手faucet龙头tradeoff交易zipper拉链pivot枢轴tolerance公差fits安装allowance余量asphalt沥青capacitor电容ceramic陶瓷inductor电感concrete混凝nentron中子porcelain瓷器proton质子rotor转子stator定子headstock主轴箱tool-post刀架tailstock尾架bed床身feed-shaft主轴进给lead-screw丝杠carriage溜板lathes车床reamer绞床grinder磨床miller铣床planer刨床drillpresses钻床boringmachines镗床turretpunches冲床flame电火花wire-cutting线切割weldingmachines焊接机床pipebenders弯管机cuttingthreads车螺纹turningtapers加工锥面centers顶尖faceplate卡盘词组parallelcircuit并联电路seriescircuit串联电路brushlessmotor无刷电机servomotor伺服电机gearmotor齿轮电机singlemotor单向电机multiphasemotor多向电机universalmotor通用电机inductionmotor同步电机synchronousmotor异步电机Spurgear正齿轮helicalgear斜齿轮changegear变速齿轮clustergear齿轮组wormgear涡轮蜗杆herringbonegear人字齿轮rackandpinion齿轮齿条anti-backlashgears无齿隙齿轮bevelgear锥齿轮mitergear等径伞齿轮offsetfollower偏心从动件potint/knifefollower尖顶从动件flatfollower平直从动件rollerfollower滚子从动件computeraideddesignCADcomputeraidedmanufacturingCAMsolidmodel实体模型wire-framemodels线框模型finiteelementmethods有限元分析surfacemodels表面模型kinematicsstudies运动学分析dynamicstudies动力学分析interferencechecking干涉检验stress-straincalculations应力应变分heattransferanalysis热传导分析Ladderdiagram梯形图dynamicsimulation动力学仿真scancycle扫描周期relaycontact继电器触点retentivetimer保持定时器solenoid线圈,螺线管ON-delaytimers通电延时定时器OFF-delaytimer断电延时定时器laserguidance激光导引drillhole钻孔reamhole铰孔borehole镗孔名词解释Basicsizeisthesizefromwhichthelimitsofsizearederivedbytheapplicationofallowancesandtolerances.基本尺寸是一个尺寸,这个尺寸极限是由公差和余量应用所得。Designsizeisthesizefromwhichyouderivethelimitsofsizebytheuseoftolerances.设计尺寸是可以通过公差的使用得到尺寸极限的尺寸。Actualsizeisthemanufacturedsizeoftheobjectthatmaybelargerorsmallerthanthenominalsize.实际尺寸是事物的人造尺寸而她可以比一般尺寸大点或小点。Unilateraltolerancesindicatevariationfromthebasicsizeinonedirection.单边公差表明基本尺寸在一个方向上的变化量。Bilateraltolerancesindicatevariationfromthebasicsizeinbothdirections.双边公差表明基本尺寸在两个方向上的变化量。Clearancefitisafitthatalwaysenablesaclearancebetweentheholeandshaftinthecoupling.Thelowerlimitsizeoftheholesisgreateroratleastequaltotheupperlimitsizeoftheshaft.间隙配合是用一种配合,它使孔和轴在配合时产生一个间隙。孔的下偏差大于等于轴的上偏差。Transitionfitisafitwhere(dependingontheactualsizesoftheholeandshaft)bothclearanceandinterferencemayoccurinthecoupling.Tolerancezonesoftheholeandshaftpartlyorcompletelyinterfere.过渡配合是间隙和过盈在配合时都会发生的一种配合。孔和轴的公差带会部分或完全覆盖。Interferencefitisafitalwaysensuringsomeinterferencebetweentheholeandshaftinthecoupling.Theupperlimitsizeoftheholeissmalleroratleastequaltothelowerlimitsizeoftheshaft.过盈配合是确认在配合时孔和轴的一些干涉量的一种配合。孔的上极限尺寸总是小于等于轴的下极限尺寸。Thebasicholesystemisasystemoffitsinwhichthedesignoftheholeslowerlimitisthebasicsizeandhasaunilateraltolerance.基孔制是一种设计孔的下偏差是基本尺寸,并且有单边公差的配合制。Thebasicshaftsystemstillisasystemoffitsinwhichthedesignsizeoftheshaftsupperlimitisthebasicsizeandalsohasaunilateraltolerance.基轴制也是一种设计轴的下偏差是基本尺寸而且也有单边公差的配合制。总结Unit5 Conventional Machining ProcessesCan you give me a list of machining processes? TuringBoringMillingDrillingGrindingPlanning车削、镗削、铣削、钻削、磨削、刨削Unit5 ConventionalMachining Processes5.1 Introduction Conventional machining is the group of machining operationsthat use single- or multi-point tools to remove material in the formof chips. Metal cutting involves removing metal through machining operations. Machining traditionally takes place onlathes, drill presses, and milling machines with the use of variouscutting tools. Most machining has very low set-up cost comparedWith machining is much more expensive for high volumes. Machiningis necessary where tight tolerances on dimensions and finishesare required.5.1 译文 传统机械加工是一组利用单刃或者多刃刀具以切屑形式去除材料的加工方式。金属切削意味着通过机械加工去除金属。传统的机械加工都是利用不同的刀具在车床、钻床和铣床上进行的。与成型加工、锻压和铸造工艺相比,大多数机械加工的生产准备成本都较低,然而如果是大批量生产,其成本要高得多。当对零件的尺寸公差和光洁度要求较高时,机械加工是很有必要的。5.2 Turning and Lathe Turning is one of the most common of metal cuttingoperations.In turning, a workpiece is rotated about its axis as single-pointcutting tools are fed into it, shearing away excess material andcreating the desired cylindrical surface. Turning can occur onbothexternal and internal surfaces to produce anaxially-symmetricalcontoured part. Parts ranging from pocket watch componentstolarge diameter marine propeller shafts can be turned on a lathe. Apart from turning, several other operations can also beperformed on lathe.marine propellerWords & expressionsaxially ksili adv.轴向地symmetrical simetrikl a. 对称的cylindrical silindrikl a.圆柱形的contoured kntud a.显示轮廓的,与某种形体轮廓相吻合的译文: 在金属切削加工操作中,车削是最常见的一种。在车削过程中,工件绕其轴线回转,单刃车刀沿工件进给,切除掉多余的材料,最后形成要求的圆柱形表面。车削可以加工外面和内表面以形成具有轴对称的成形工件。从怀表的零件到大直径的船用螺旋桨轴都可以在车床上加工。 除了车削,还有另外几种加工操作都可以在车床上进行。5.2 Turning and LatheBoring and internal turning. Boring and internal turning areperformed on the internal surfaces by a boring bar or suitableinternal cutting tools. If the initial workpiece is solid, a drillingoperation must be performed first. The drilling tool is held inthetailstock, and the latter is then fed against the workpiece. Whenboring is done in a lathe, the work usually is held in a chuck orona face plate. Holes may be bored straight, tapered, or toirregularcontours. Boring is essentially internal turning while feeding thetool parallel to the rotation axis of the workpiece. Words & expressionstailstock teilstk n. 尾座chuck tk n.卡盘,夹头译文: 利用镗杆或合适的内圆车刀可以进行镗削和车内圆。如果工件毛坯是实心的,首先要钻孔。钻头安装在尾架上,后者向工件进给。如果在车床上进行镗削加工,工件通常装夹在卡盘或者花盘上。镗出的孔可以是直孔、锥孔或者不规则轮廓。当将刀具沿工件的回转轴线平行进给时,镗削实际上就是车内圆。Facing. Facing is the producing of a flat surface as the result ofatools being fed across the end of the rotating workpiece. Unlessthe work is held on a mandrel, if both ends of the work are tobefaced, it must be turned around after the first end is completedand then the facing operation repeated. The cutting speedshouldbe determined from the largest diameter of the surface to be faced.Facing may be done either from the outside inward or fromthecenter outward. In either case, the point of the tool must be setexactly at the height of center of rotation.Because the cutting force tends to push the tool away from thework, it is usually desirable to clamp the carriage to the lathebedduring each facing cut to prevent it from moving slightly andthusproducing a surface that is not flat. In the facing of casting orothermaterials that have a hard surface, the depth of the first cutshouldbe sufficient to penetrate the hard material to avoid excessivetoolwear. Words & expressionsmandrel mndrl n.车床心轴clamp klmp v. 夹紧,夹住carriage krid n.大刀架,拖板penetrate penitreit v. 穿透,渗透tool wear 刀具磨损译文: 车端面可以加工出一个平面,它是当车刀沿回转工件的端面横向进给的结果。除非工件固定在心轴上,如果工件两端都要车端面,必须将一端加工完成后,将工件调头,重复进行车端面加工。车削速度必须由所加工表面的最大直径来决定。车端面可以由外向内也可以由中心向外进行。无论哪种情况,刀尖必须准确地与回转中心对正。由于切削力有将车刀推离工件的趋势,通常最可行的就是在车端面时将拖板卡紧在床身上以避免车刀轻微移动造成加工表面不平整。在对具有硬质表面的铸件或其他材料进行车端面加工时,首次切深要足以穿透硬质材料从而避免过度的刀具磨损。Parting. Parting is the operation by which one section of aworkpiece is severed from the remainder by means of cutofftool.Because cutting tools are quite thin and must have considerableoverhang, this process is less accurate and more difficult. Thetoolshould be set exactly at the height of axis of rotation, be keptsharp,have proper clearance angles, and be fed into the workpiece ataproper and uniform feed rate. Words & expressionsremainder rimeind剩余物 ,余数overhang uvh vt.悬于.之上 n.伸出;突出uniform ju:nif:m a.相同的,一致的 n.制服;军服clearance angles 后角译文: 切断是一种利用切断刀(割刀)将工件的一部分与其剩余部分脱离的加工方法。由于切断刀非常薄而且处于悬臂状态,因此这种加工方法不太精确而且加工起来常常比较困难。切断刀必须准确地对正回转轴,保持锋利,具有合适的后角,以合适、不变的进给率沿工件进给。Threading. Threading can be considered as turning since thepathto be travelled by the cutting tool is helical. However, there aresome major differences between turning and threading. Whileinturning, the interest is in generating a smooth cylindricalsurface,in threading the interest is in cutting a helical thread of a givenform and depth which can be calculated from the formulae.helical helikl a.螺旋状的译文: 车螺纹可以看作是车削,只是车刀所形成的加工轨迹是螺旋线。但二者也存在一些不同之处。车削主要考虑能否生成光滑的圆柱形表面,而车螺纹注重的是能否切出具有按公式计算出来的规定形状和深度的螺旋线。There are two basic requirements for thread cutting. An accurately shaped and properly mounted tool is neededbecausethread cutting is a form-cutting operation. The resulting threadprofile is determined by the shape of the tool and its positionrelativeto the workpiece. The second by requirement is that the tool must movelongitudinallyin a specific relationship to the rotation of workpiece, becausethisdetermines the lead of the thread. This requirement is metthroughthe use of the lead screw and the split unit, which providepositivemotion of carriage relative to the rotation of spindle. form-cutting operation 成形加工longitudinally l:ditju:dinli adv.纵向lead screw 丝杠split unit 开合机构5.2 Turning and Lathe译文: 因此车刀必须具有准确的形状而且要安装合适。所切出的螺纹外形是由车刀形状和它与工件的相对位置决定的。其次,车刀的纵向进给与工件的回转运动具有特定的关系,因此这决定了螺纹的导程。这个条件可以通过采用丝杠和开合机构得到满足,它们可以实现拖板相对于主轴回转运动的精确可靠的运动。Lathe. Many types of lathes are used for production turning.According to purposes and construction, lathe-type machinetoolscan be classified as follow:1. Engine lathes 普通车床2. Vertical lathes 立式车床3. Turret lathes 转塔车床4. Single-or multiple-spindle automatic or semi-automatic lathes5. Contouring lathes 仿形车床6. Universal lathes 万能车床7. Special-purpose lathes such as crankshaft lathes, camshaft lathes, car wheel lathes and backing-off lathes, etc.5.2 Turning and LatheLathe bed is foundation of the engine lathe, which is heavy,ruggedcasting made to support the working parts of the lathe. The sizeand mass of the bed gives the rigidity necessary for accurateengineering tolerances required in manufacturing. On top of thebed are machined slideways that guide and align the carriageandtailstock, as they are move from one end of the lathe to the other. rugged adj. 健壮,坚固 mass n. 质量 slideways n.导轨 床身是普通车床的基础,它是由沉重而坚固的铸件制作而成的,其目的是为了支撑车床的工作部件。床身的尺寸和质量要使车床具有足够的刚性以保证制造过程中获得所需的工程公差。床身上的导轨可以引导和对准拖板和尾座,使它们可以从车床的一端移动到另一端。5.2 Turning and Lathe Headstock is clamped atop the bed at left-hand end of the latheand contains the motor that drives the spindle whose axis isparallel to the guideways through a series of gears housedwithin the gearbox. The function of gearbox is to generate anumber of different spindle speeds. atop adv. 在()顶上 gearbox 齿轮箱 床头箱(主轴箱)紧固在床身上面的左端,内装有电机,它通过变速箱内的一组齿轮来驱动主轴转动,主轴的轴线平行于导轨。变速箱的功能是可以产生不同的主轴转速。5.2 Turning and Lathe A spindle gear is mounted on the rear of the spindle totransmitpower through the change gears to the feeding box thatdistributes the power to the lead screw for threading or tothefeed rod for turning. on the rear of 在的尾部 change gears 挂轮 lead screw 丝杠 feed rod 光杠 主轴齿轮安装在主轴的尾部,通过挂轮把动力传递到进给箱,如果是车螺纹,进给箱将动力分配到丝杠上;如果是车削,就将动力分配到光杠上。5.2 Turning and Lathe The spindle has a through hole extending lengthwise throughwhich bar stocks can be fed if continuous production is used.The hole can hold a plain lathe center by its tapered innersurface and mount a chuck, a face plate or collet by itsthreadedouter surface. taper n.坡度,锥形 v.锥度加工 collet n.夹头主轴有一个纵向通孔,如果连续加工棒料,通孔就用来实现棒料的送料。这个通孔具有一个内锥面,可以安装普通车床的中心顶尖。主轴的外表面车有螺纹,可以安装卡盘,花盘或夹头。5.2 Turning and LatheCarriage assembly is actually an H-shaped block that sits acrossthe guideways and in front of lathe bed. The function of thecarriage is to carry and move the cutting tool longitudinally. Itcan be moved by hand or by power and can be clamped intoposition with a locking nut. The carriage is composed of thecross slide, compound rest, tool saddle, and apron. 拖板组件实际上是一个H形的铸件,位于床身的前端并横跨在导轨上。拖板的功能带动刀具纵向移动,这个可以通过手动或者自动完成。利用锁紧螺母可以将其卡紧在所需位置。拖板组件由横拖板,小刀架,刀架鞍板和溜板箱组成。5.2 Turning and Lathecross slide 横拖板Carriage assembly拖板组件apron 溜板箱5.2 Turning and Lathe The cross slide is mounted on the dovetail guideways on the topof the saddle and it moved back and forth at 90to the axis ofthe lathe by the cross slide lead screw. The lead screw can behand or power activated. dovetail 燕尾槽横拖板安装在刀架鞍板上部的燕尾槽导轨上。它利用横拖板丝杠于车床轴线成90度夹角的方向上前后移动。丝杠可以手动或者自动驱动。5.2 Turning and Lathe The compound rest is mounted on the cross slide and can beswiveled and clamped at any angle in a horizontal plane. Thecompound is typically used for cutting chamfers or tapers,butmust also be used when cutting thread. The compound restcanonly be fed by hand. There is no power to compound rest.Thecutting tool and tool holder are secured in the tool post whichismounted directly to the compound rest. swivel swvl v.旋转小刀架安装在横拖板上,它可以在水平面内转动或夹紧在任意角度位置。小刀架主要用来倒角和加工锥面,在车削螺纹时也必须用到小刀架。小刀架只能手动进给,没有动力传到小刀架上。刀具和刀夹被卡紧在直接安装在小刀架上的刀座上。5.2 Turning and LatheThe tool saddle is an H shaped casting mounted on the top oftheguideways and houses the cross slide and compound rest. Itmakespossible longitudinal, cross and angular feeding of the tool bit. 刀架鞍板是一个安装在导轨上部的H形铸件,容纳有横拖板和小刀架。它可以实现刀尖的纵向、横向和斜向进给。5.2 Turning and LatheThe apron is attached to the front of the carriage and containsthegears and feed clutches which transmit motion from the feedrodor lead screw to carriage and cross slide. When cutting screwthreads, power is provided to the gearbox of the apron by theleadscrew. In all other turning operations, it is the feed rod thatdrivesthe carriage. 溜板箱位于拖板的前端,里面装有齿轮和将运动从光杠或丝杠传递至拖板或横向拖板的进给离合器。当切制螺纹时,动力通过丝杠传递到溜板箱中的变速齿轮箱。在其它车削加工时,依靠光杠来驱动拖板。5.2 Turning and Lathe Tailstock is composed of a low base and the movable part ofthe tail-stock proper, the transverse adjustments being madewith a cross screw furnished with a square head. The twoparts are hold together by the holding-down bolts which securethe tailstock to the bed. transverse adj. 横向的,横切的; n. 横轴 holding-down bolts 压紧螺栓 尾座由底座和尾座体的可移动部件组成。课移动部件的横向调整有带有四方头的横向丝杠来完成。底座和可移动部分通过压紧螺栓连接在一起并将尾座固定在床身上。5.2 Turning and Lathe The tailsto
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