机械设计制造及其自动化外文翻译外文文献英文文献普通钻床改造为多轴钻床复习过程
机械设计制造及自动化中英文对照外文翻译文献
机械设计制造及⾃动化中英⽂对照外⽂翻译⽂献中英⽂对照外⽂翻译⽂献(⽂档含英⽂原⽂和中⽂翻译)使⽤CBN砂轮对螺杆转⼦进⾏精密磨削的⽅法摘要：针对⾼精度加⼯螺杆转⼦，这篇论⽂介绍了利⽤⽴⽅氮化硼（CBN砂轮）对螺杆转⼦进⾏精密磨削的加⼯⽅法。
⾸先，使⽤⼩型电镀CBN砂轮磨削螺杆转⼦。
精确的CBN砂轮轴向轮廓的模型是在齿轮啮合理论的基础上建⽴开发的。
考虑到螺杆转⼦和涂层厚度之间的间隙，主动砂轮的修整引⼊了CBN的砂轮的设计⽅法。
主动砂轮的形状采⽤低速电⽕花线切割技术（低速⾛丝线切割机）进⾏加⼯线CBN主动砂轮的成形车⼑采⽤低速⾛丝机切割机进⾏加⼯。
CBN螺杆转⼦砂轮采⽤本⽂提出的原理进⾏有效性和正确性的验证。
电镀CBN砂轮对螺杆转⼦进⾏加⼯，同时进⾏机械加⼯实验。
在实验中获得的数据达到GB10095-88五级认证。
关键词： CBN砂轮精密磨削螺杆转⼦砂轮外形修整专业术语⽬录：P 螺杆转⼦的参数H 螺杆转⼦的直径Σ砂轮和转⼦的安装⾓度Au 砂轮和转⼦的中⼼距8 螺旋转⼦接触点的旋转⾓x1, y1, z1:转⼦在σ系统中的位置x, y, z: 砂轮端⾯的位置x u ,y u ,z u: x, x y z轴的法向量n x ,ny,nz:X Y Z轴的端⾯法向量n u , nu, nu:砂轮的⾓速度的⽮量:砂轮模块的⾓速度wu:螺旋转⼦的⾓速度w1螺旋转⼦模块的⾓速度转⼦接触点的⾓速度转⼦表⾯接触点的初始速度砂轮表⾯接触点的⾓速度砂轮表⾯接触点的初始速度l砂轮的理论半径砂轮轴的理想位置砂轮表⾯的修改半径砂轮轴的修改位置砂轮表⾯的法向量1.引⾔螺旋转⼦是螺杆压缩机、螺钉、碎纸机以及螺杆泵的关键部分。
转⼦的加⼯精度决定了机械性能。
⼀般来说，铣⼑⽤于加⼯螺旋转⼦。
许多研究者，如肖等⼈[ 1 ]和姚等⼈[ 2 ]，对⽤铣⼑加⼯螺旋转⼦做了⼤量的⼯作。
该⽅法可以提⾼加⼯效率。
然⽽，加⼯精度低和表⾯粗糙度不⾼是其主要缺点。
机械设计制造及其自动化外文翻译外文文献英文文献普通钻床改造为多轴钻床
普通钻床改造为多轴钻床目前，我国中、小型企业的产品质量和生产效率都需要有一个新的提高,但是加工手段却远远不能满足需要,许多中小型企业都结合自己的实际对设备的技术状态进行改进，通过强化自身,以求自我发展普通钻床为单轴机床，但安装上多轴箱就会成为多轴的钻床，改造成多轴钻床后，能大大地缩短加工时间，提高生产效率。
多轴加工应用：据统计，一般在车间中普通机床的平均切削时间很少超过全部工作时间的15%。
其余时间是看图、装卸工件、调换刀具、操作机床、测量以及清除铁屑等等。
使用数控机床虽然能提高85%，但购置费用大。
某些情况下，即使生产率高，但加工相同的零件，其成本不一定比普通机床低。
故必须更多地缩短加工时间。
不同的加工方法有不同的特点，就钻削加工而言，多轴加工是一种通过少量投资来提高生产率的有效措施。
多轴加工优势：虽然不可调式多轴头在自动线中早有应用，但只局限于大批量生产。
即使采用可调式多轴头扩大了使用范围，仍然远不能满足批量小、孔型复杂的要求。
尤其随着工业的发展，大型复杂的多轴加工更是引人注目。
例如原子能发电站中大型冷凝器水冷壁管板有15000个ψ20孔，若以摇臂钻床加工，单单钻孔与锪沉头孔就要842.5小时，另外还要划线工时151.1小时。
但若以数控八轴落地钻床加工，钻锪孔只要171.6小时，划线也简单，只要1.9小时。
因此，利用数控控制的二个坐标轴，使刀具正确地对准加工位置，结合多轴加工不但可以扩大加工范围，而且在提高精度的基础上还能大大地提高工效，迅速地制造出原来不易加工的零件。
有人分析大型高速柴油机30种箱形与杆形零件的2000多个钻孔操作中，有40%可以在自动更换主轴箱机床中用二轴、三轴或四轴多轴头加工，平均可减少20%的加工时间。
1975年法国巴黎机床展览会也反映了多轴加工的使用愈来愈多这一趋势。
多轴加工的设备：多轴加工是在一次进给中同时加工许多孔或同时在许多相同或不同工件上各加工一个孔。
这不仅缩短切削时间，提高精度，减少装夹或定位时间，并且在数控机床中不必计算坐标，减少字块数而简化编程。
毕业设计论文外文文献翻译机械设计制造及其自动化轴承的摩擦与润滑中英文对照
Friction , Lubrication of BearingIn many of the problem thus far , the student has been asked to disregard or neglect friction . A ctually , friction is present to some degree whenever two parts are in contact and move on each other. The term friction refers to the resistance of two or more parts to movement.Friction is harmful or valuable depending upon where it occurs. friction is necessary for fastening devices such as screws and rivets which depend upon friction to hold the fastener and the parts together. Belt drivers, brakes, and tires are additional applications where friction is necessary.The friction of moving parts in a machine is harmful because it reduces the mechanical advantage of the device. The heat produced by friction is lost energy because no work takes place. A lso , greater power is required to overcome the increased friction. Heat is destructive in that it causes expansion. Expansion may cause a bearing or sliding surface to fit tighter. If a great enough pressure builds up because made from low temperature materials may melt.There are three types of friction which must be overcome in moving parts: (1)starting, (2)sliding,and(3)rolling. Starting friction is the friction between two solids that tend to resist movement. When two parts are at a state of rest, the surface irregularities of both parts tend to interlock and form a wedging action. T o produce motion in these parts, the wedge-shaped peaks and valleys of the stationary surfaces must be made to slide out and over each other. The rougher the two surfaces, the greater is starting friction resulting from their movement .Since there is usually no fixed pattern between the peaks and valleys of two mating parts, the irregularities do not interlock once the parts are in motion but slide over each other. The friction of the two surfaces is known as sliding friction. A s shown in figure ,starting friction is always greater than sliding friction .Rolling friction occurs when roller devces are subjected to tremendous stress which cause the parts to change shape or deform. Under these conditions, the material in front of a roller tends to pile up and forces the object to roll slightly uphill. This changing of shape , known as deformation, causes a movement of molecules. As a result ,heat is produced from the added energy required to keep the parts turning and overcome friction.The friction caused by the wedging action of surface irregularities can be overcome partly by the precision machining of the surfaces. However, even these smooth surfaces may require the use of a substance between them to reduce the friction still more. This substance is usually a lubricant which provides a fine, thin oil film. The film keeps the surfaces apart and prevents the cohesive forces of the surfaces from coming in close contact and producing heat .Another way to reduce friction is to use different materials for the bearing surfaces and rotating parts. This explains why bronze bearings, soft alloy s, and copper and tin iolite bearings are used with both soft andhardened steel shaft. The iolite bearing is porous. Thus, when the bearing is dipped in oil, capillary action carries the oil through the spaces of the bearing. This type of bearing carries its own lubricant to the points where the pressures are the greatest.Moving parts are lubricated to reduce friction, wear, and heat. The most commonly used lubricants are oils, greases, and graphite compounds. Each lubricant serves a different purpose. The conditions under which two moving surfaces are to work determine the type of lubricant to be used and the system selected for distributing the lubricant.On slow moving parts with a minimum of pressure, an oil groove is usually sufficient to distribute the required quantity of lubricant to the surfaces moving on each other .A second common method of lubrication is the splash system in which parts moving in a reservoir of lubricant pick up sufficient oil which is then distributed to all moving parts during each cycle. This system is used in the crankcase of lawn-mower engines to lubricate the crankshaft, connecting rod ,and parts of the piston.A lubrication system commonly used in industrial plants is the pressure system. In this system, a pump on a machine carries the lubricant to all of the bearing surfaces at a constant rate and quantity.There are numerous other sy stems of lubrication and a considerable number of lubricants available for any given set of operating conditions. Modern industry pays greater attention to the use of the proper lubricants than at previous time because of the increased speeds, pressures, and operating demands placed on equipment and devices.Although one of the main purposes of lubrication is reduce friction, any substance-liquid , solid , or gaseous-capable of controlling friction and wear between sliding surfaces can be classed as a lubricant.V arieties of lubricationUnlubricated sliding. Metals that have been carefully treated to remove all foreign materials seize and weld to one another when slid together. In the absence of such a high degree of cleanliness, adsorbed gases, water vapor ,oxides, and contaminants reduce frictio9n and the tendency to seize but usually result in severe wear。
机械设计过程外文文献翻译、中英文翻译
附录英文Machine design processThe machine is the organization with other components combinations, transforms，the transmission or using the energ，the strength or the movementexample for the beneficial use has the engine．the turbine wheel，the vehicles．the hoist，the printer，the washer and the movie camera Many is suitable tbr themachine design principle and the strength law also is suitable to is not thegenuine machine finished product．the driven wheel hub and the file cabinet tothe measuring appl iance and the nuclear pressure vessel．”Machine designt thisterminology compared to”machine design”more generalized，it including machine design．But regarding certain instruments．1ike uses to determine hot，the mobile line and the volume thermal energy as well as the fluid aspect question needs alone to consider．But when machine design must consider themovement and the structure aspect question as well as preserved and the sealstipulation．In the mechanical engineering domain and all that project domainapplication machine design，all need such as mechanism and so on the svdtch,cam，valve，vessel and mixer．The design beginning tO being true or the imagination need．The existing instrument possibly needs in the durability，the efficiency，the weight，the speedor the cost performs to improve．]he possible need new instrument tO completebefore made the function by the person．1ike t was abundant Assembly or maintenance．After the goal completely or partially determines，the design nextstep is the idea carl complete needs the ffmction the organization and its thearrangement for this，the free hand drawing schematic diagram value is enormous，it not only takes a person idea the recording and the auxiliary．methodwhich if the other people discusses，moreover especially is suitable for with ownidea exchange，also needs to concern as the creative mentality stimulant to thepart widespread knowledge，because a new machine frequently by knew very well each kind of components rearrange or the replace become，perhaps changedthe size and the material．Regardless of after idea process or，a designer callcarry on fast either the sketchy computation or the analysis determines thegeneral size and the feasibility．After about need or may use the spatial meteidea determination，may start according to the proportion picture schematicdiagram．When several components approximate shapes and several sizes come out，the analysis was allowed truly to start．The analysis goal lies in enable it to havesatisfying or the superior performance，as well as will seek the best proportionand the size under the smallest weight security and the durability and thecompetitive cost designer for each essential load bearing section，as well asseveral components intensities balance then choice material and processingmethod．These important goals only have through only then may obtain based on the mechanism analysis，like about reacting force and friction most superioruse principie of statics；About inertia，acceleration and energy principle ofdynamics：About stress and deflection material elasticity and intensity principle；About material physical behavior principle；About lubrication and water poweractuation hydromechanics principle．The analysis may identical engineer whicharranges by the idea machinery do，or makes the analysis in the big company bythe independent analysis department or the research group the result，possibleneed new arrangement and new size．No matter is officially does orunofficialdoes，supposes Japan is relapse and the cooperation process．the analysis staffmay play the role to all stages but not merely is he stage.Some design criteriaIn this part，some people suggested carries on the analysis using the creative manner，this kind of analysis may cause the significant improvement aswell as to the spare product idea and the consummation，the product functionmore．more economical，is perhaps more durable． The creation stage does notneed is at first and the independent stage．Alttlough the analysis staff possiblycertainlv is not responsible for the entire design，but he not meyely is can fromthe numeral proposc wants question correct answer which he soIVes，not merelyis Droduces the stress value，the size or the work limit. He may propose a morewidespread opinion，in order to improvement standard or plan. Because beforethe analysis or in the analysis process，he can familiar install and its the workingcondition．he is in an idea to prepare chooses the plan the rantage Poinl．Best hecan propose the suggestion transfigure eliminates the moment of force or thestress concentration，but was not the permission constructs has the blgsectlonand the excessively many dynamic loads organization should better be he discards his careful desi{；n but is not afterwards saw the machinery discarded.In order to stimulate the creative thought，below suggested designs thepersonnel and the analysis staff uses the criterion.The first 6 criteria especially are suitable for the analysis staff,although he possibly involves to possesses this l o items.1．Creatively the use needs the physical performance and the control doesnot need．2．Knows the practical load and its the importance.3．D00s not consider the function load in advance.4．Invents the more advantageous loading environment.5．Provides the minimurn weight the most advantageous stress distributionand the rigidity．6．uses the fundamental equation computation proportion and causes thesize optimization．7．The selection material obtains the perlbrmance combination．8．In between spare parts and integrated components carefid choice． 9．Revisions functional design adapts the production process and reduces thecost．10．In the consideration assembly causes the part pintpointing and mutuallydoes not disturb．Designs the personnel to have in such domain，like the statics，the inematics，dynamics and the materials mechanics have the good accomplishment，in addition．but also must familiar make the material and themanufacture craft．Designs the personnel to have to be able to combine allcollrelations the fact，carries on teaches Wei．the manufacture schematic diagramand the charting comes the manufacture request totransmit the workshop． Any product design one of first step of work is the choice uses in to makeeach part the material．Today design personnel may obtain innumerably．When choice，the product function，the outward appearance，the material cost and theproduction cost very are all important．Before any computation must carefullyappraise the material the performance．It is the necessary careful computation toguarantee the design the validity The computation ever does not appear on thechart，but is saved by ten each kind of reason．Once any part expires，had makeclear when is designing at first this had the flaw the components has made any；Moreover，。
机械设计制造及其自动化毕业设计外文翻译
机械设计制造及其自动化毕业设计外文翻译英文原文名Automatic production line PLC control of automatic feeding station中文译名基于PLC的自动化生产线自动上料站的控制中文译文：自动化生产线自动上料站的PLC控制自动生产线是由工件传送系统和控制系统，将一组自动机床和辅助设备按照工艺顺序联结起来，自动完成产品全部或部分制造过程的生产系统，简称自动线。
二十世纪20年代，随着汽车、滚动轴承、小电机和缝纫机和其他工业发展,机械制造业开始出现在自动生产线,第一个是组合机床自动线。
在20世纪20年代,第一次出现在汽车工业流水生产线和半自动生产线,然后发展成自动生产线。
第二次世界大战后,在机械制造工业发达国家,自动生产线的数量急剧增加。
采用自动生产线生产的产品应该足够大,产品设计和技术应该是先进的、稳定的和可靠的,基本上保持了很长一段时间维持不变。
自动线用于大,大规模生产可以提高劳动生产率,稳定和提高产品质量,改善劳动条件,降低生产区域,降低生产成本,缩短生产周期,保证生产平衡、显著的经济效益。
自动生产线的一个干预指定的程序或命令自动操作或控制的过程,我们的目标是稳定、准确、快速。
自动化技术广泛用于工业、农业、军事、科学研究、交通运输、商业、医疗、服务和家庭,等自动化生产线不仅可以使人们从繁重的体力劳动、部分脑力劳动以及恶劣、危险的工作环境,能扩大人的器官功能,极大地提高劳动生产率,提高人们认识世界的能力,可以改变世界。
下面我说下它的应用范围：机械制造业中有铸造、锻造、冲压、热处理、焊接、切削加工和机械装配等自动线，也有包括不同性质的工序，如毛坯制造、加工、装配、检验和包装等的综合自动线。
加工自动线发展最快,应用最广泛的机械制造。
主要包括:用于处理盒、外壳、各种各样的部件,如组合机床自动线;用于加工轴、盘部分,由通用、专业化、或自动机器自动专线;转子加工自动线;转子自动线加工过程简单、小零件等。
机械类外文文献及翻译
机械类外文文献及翻译(文档含中英文对照即英文原文和中文翻译)原文：GEAR AND SHAFT INTRODUCTIONAbstract:The important position of the wheel gear and shaft can't falter in traditional machine and modern machines.The wheel gear and shafts mainly install the direction that delivers the dint at the principal axis box. The passing to process to make them can is divided into many model numbers, using for many situations respectively. So we must be the multilayers to the understanding of the wheel gear and shaft in many ways .Key words: Wheel gear; ShaftIn the force analysis of spur gears, the forces are assumed to act in a single plane. We shall study gears in which the forces have three dimensions. The reason for this, in the case of helical gears, is that the teeth are not parallel to the axis of rotation. And in the case ofbevel gears, the rotational axes are not parallel to each other. There are also other reasons, as we shall learn.Helical gears are used to transmit motion between parallel shafts. The helix angle is the same on each gear, but one gear must have a right-hand helix and the other a left-hand helix. The shape of the tooth is an involute helicoid. If a piece of paper cut in the shape of a parallelogram is wrapped around a cylinder, the angular edge of the paper becomes a helix. If we unwind this paper, each point on the angular edge generates an involute curve. The surface obtained when every point on the edge generates an involute is called an involute helicoid.The initial contact of spur-gear teeth is a line extending all the way across the face of the tooth. The initial contact of helical gear teeth is a point, which changes into a line as the teeth come into more engagement. In spur gears the line of contact is parallel to the axis of the rotation; in helical gears, the line is diagonal across the face of the tooth. It is this gradual of the teeth and the smooth transfer of load from one tooth to another, which give helical gears the ability to transmit heavy loads at high speeds. Helical gears subject the shaft bearings to both radial and thrust loads. When the thrust loads become high or are objectionable for other reasons, it may be desirable to use double helical gears. A double helical gear (herringbone) is equivalent to two helical gears of opposite hand, mounted side by side on the same shaft. They develop opposite thrust reactions and thus cancel out the thrust load. When two or more single helical gears are mounted on the same shaft, the hand of the gears should be selected so as to produce the minimum thrust load.Crossed-helical, or spiral, gears are those in which the shaft centerlines are neither parallel nor intersecting. The teeth of crossed-helical fears have point contact with each other, which changes to line contact as the gears wear in. For this reason they will carry out very small loads and are mainly for instrumental applications, and are definitely not recommended for use in the transmission of power. There is on difference between a crossed heli : cal gear and a helical gear until they are mounted in mesh with each other. They are manufactured in the same way. A pair of meshed crossed helical gears usually have the same hand; that is ,a right-hand driver goes with a right-hand driven. In the design of crossed-helical gears, the minimum sliding velocity is obtained when the helix angle areequal. However, when the helix angle are not equal, the gear with the larger helix angle should be used as the driver if both gears have the same hand.Worm gears are similar to crossed helical gears. The pinion or worm has a small number of teeth, usually one to four, and since they completely wrap around the pitch cylinder they are called threads. Its mating gear is called a worm gear, which is not a true helical gear. A worm and worm gear are used to provide a high angular-velocity reduction between nonintersecting shafts which are usually at right angle. The worm gear is not a helical gear because its face is made concave to fit the curvature of the worm in order to provide line contact instead of point contact. However, a disadvantage of worm gearing is the high sliding velocities across the teeth, the same as with crossed helical gears.Worm gearing are either single or double enveloping. A single-enveloping gearing is onein which the gear wraps around or partially encloses the worm.. A gearing in which each element partially encloses the other is, of course, a double-enveloping worm gearing. The important difference between the two is that area contact exists between the teeth of double-enveloping gears while only line contact between those of single-enveloping gears. The worm and worm gear of a set have the same hand of helix as for crossed helical gears, but the helix angles are usually quite different. The helix angle on the worm is generally quite large, and that on the gear very small. Because of this, it is usual to specify the lead angle on the worm, which is the complement of the worm helix angle, and the helix angle on the gear; the two angles are equal for a 0-deg. Shaft angle.When gears are to be used to transmit motion between intersecting shaft, some of bevel gear is required. Although bevel gear are usually made for a shaft angle of 0 deg. They may be produced for almost any shaft angle. The teeth may be cast, milled, or generated. Only the generated teeth may be classed as accurate. In a typical bevel gear mounting, one of the gear is often mounted outboard of the bearing. This means that shaft deflection can be more pronounced and have a greater effect on the contact of teeth. Another difficulty, which occurs in predicting the stress in bevel-gear teeth, is the fact the teeth are tapered.Straight bevel gears are easy to design and simple to manufacture and give very good results in service if they are mounted accurately and positively. As in the case of squr gears, however, they become noisy at higher values of the pitch-line velocity. In these cases it is often go : od design practice to go to the spiral bevel gear, which is the bevel counterpart of thehelical gear. As in the case of helical gears, spiral bevel gears give a much smoother tooth action than straight bevel gears, and hence are useful where high speed are encountered.It is frequently desirable, as in the case of automotive differential applications, to have gearing similar to bevel gears but with the shaft offset. Such gears are called hypoid gears because their pitch surfaces are hyperboloids of revolution. The tooth action between such gears is a combination of rolling and sliding along a straight line and has much in common with that of worm gears.A shaft is a rotating or stationary member, usually of circular cross section, having mounted upon it such elementsas gears, pulleys, flywheels, cranks, sprockets, and other power-transmission elements. Shaft may be subjected to bending, tension, compression, or torsional loads, acting singly or in combination with one another. When they are combined, one may expect to find both static and fatigue strength to be important design considerations, since a single shaft may be subjected to static stresses, completely reversed, and repeated stresses, all acting at the same time.The word “shaft” covers numerous v ariations, such as axles and spindles. Anaxle is a shaft, wither stationary or rotating, nor subjected to torsion load. A shirt rotating shaft is often called a spindle.When either the lateral or the torsional deflection of a shaft must be held to close limits, the shaft must be sized on the basis of deflection before analyzing the stresses. The reason for this is that, if the shaft is made stiff enough so that the deflection is not too large, it is probable that the resulting stresses will be safe. But by no means should the designer assume that they are safe; it is almost always necessary to calculate them so that he knows they are within acceptable limits. Whenever possible, the power-transmission elements, such as gears or pullets, should be located close to the supporting bearings, This reduces the bending moment, and hence the deflection and bending stress.Although the von Mises-Hencky-Goodman method is difficult to use in design of shaft, it probably comes closest to predicting actual failure. Thus it is a good way of checking a shaft that has already been designed or of discovering why a particular shaft has failed in service. Furthermore, there are a considerable number of shaft-design problems in which the dimension are pretty well limited by other considerations, such as rigidity, and it is only necessary for the designer to discover something about the fillet sizes, heat-treatment,and surface finish and whether or not shot peening is necessary in order to achieve the required life and reliability.Because of the similarity of their functions, clutches and brakes are treated together. In a simplified dynamic representation of a friction clutch, or brake, two in : ertias I and I traveling at the respective angular velocities W and W, one of which may be zero in the case of brake, are to be brought to the same speed by engaging the clutch or brake. Slippage occurs because the two elements are running at different speeds and energy is dissipated during actuation, resulting in a temperature rise. In analyzing the performance of these devices we shall be interested in the actuating force, the torque transmitted, the energy loss and the temperature rise. The torque transmitted is related to the actuating force, the coefficient of friction, and the geometry of the clutch or brake. This is problem in static, which will have to be studied separately for eath geometric configuration. However, temperature rise is related to energy loss and can be studied without regard to the type of brake or clutch because the geometry of interest is the heat-dissipating surfaces. The various types of clutches and brakes may be classified as fllows:. Rim type with internally expanding shoes. Rim type with externally contracting shoes. Band type. Disk or axial type. Cone type. Miscellaneous typeThe analysis of all type of friction clutches and brakes use the same general procedure. The following step are necessary:. Assume or determine the distribution of pressure on the frictional surfaces.. Find a relation between the maximum pressure and the pressure at any point. Apply the condition of statical equilibrium to find (a) the actuating force, (b) the torque, and (c) the support reactions.Miscellaneous clutches include several types, such as the positive-contact clutches, overload-release clutches, overrunning clutches, magnetic fluid clutches, and others.A positive-contact clutch consists of a shift lever and two jaws. The greatest differences between the various types of positive clutches are concerned with the design of the jaws. To provide a longer period of time for shift action during engagement, the jaws may be ratchet-shaped, or gear-tooth-shaped. Sometimes a great many teeth or jaws are used, and they may be cut either circumferentially, so that they engage by cylindrical mating, or on the faces of the mating elements.Although positive clutches are not used to the extent of the frictional-contact type, they do have important applications where synchronous operation is required.Devices such as linear drives or motor-operated screw drivers must run to definite limit and then come to a stop. An overload-release type of clutch is required for these applications. These clutches are usually spring-loaded so as to release at a predetermined toque. The clicking sound which is heard when the overload point is reached is considered to be a desirable signal.An overrunning clutch or coupling permits the driven member of a machine to “freewheel” or “overrun” bec ause the driver is stopped or because another source of power increase the speed of the driven. This : type of clutch usually uses rollers or balls mounted between an outer sleeve and an inner member having flats machined around the periphery. Driving action is obtained by wedging the rollers between the sleeve and the flats. The clutch is therefore equivalent to a pawl and ratchet with an infinite number of teeth.Magnetic fluid clutch or brake is a relatively new development which has two parallel magnetic plates. Between these plates is a lubricated magnetic powder mixture. An electromagnetic coil is inserted somewhere in the magnetic circuit. By varying the excitation to this coil, the shearing strength of the magnetic fluid mixture may be accurately controlled. Thus any condition from a full slip to a frozen lockup may be obtained.齿轮和轴的介绍摘要:在传统机械和现代机械中齿轮和轴的重要地位是不可动摇的。
机械设计类英文文献及翻译
The Sunflower Seed Huller and Oil PressBy Jeff Cox-- from Organic Gardening, April 1979, Rodale PressIN 2,500 SQUARE FEET, a family of four can grow each year enough sunflower seed to produce three gallons of homemade vegetable oil suitable for salads or cooking and 20 pounds of nutritious, dehulled seed -- with enough broken seeds left over to feed a winter's worth of birds.The problem, heretofore, with sunflower seeds was the difficulty of dehulling them at home, and the lack of a device for expressing oil from the seeds. About six months ago, we decided to change all that. The job was to find out who makes a sunflower seed dehuller or to devise one if none were manufactured. And to either locate a home-scale oilseed press or devise one. No mean task.Our researches took us from North Dakota -- hub of commercial sunflower activity in the nation -- to a search of the files in the U.S. Patent Office, with stops in between. We turned up a lot of big machinery, discovered how difficult it is to buy really pure, unrefined vegetable oils, but found no small-scale equipment to dehull sunflowers or press out their oil. The key to success, however, was on our desk the whole time. In spring 1977, August Kormier had submitted a free-lance article describing how he used a Corona grain mill to dehull his sunflower seeds, and his vacuum cleaner exhaust hose to blow the hulls off the kernels. A second separation floated off the remaining hulls, leaving a clean product. We'd tried it, but because some kernels were cracked and the process involved drying, we hadn't been satisfied. Now we felt the best approach was to begin again with what we learned from Mr. Kormier and refine it.Staff Editor Diana Branch and Home Workplace Editor Jim Eldon worked with a number of hand- and electric-powered grain mills. While the Corona did a passable job, they got the best results with the C.S. Bell #60 hand mill and the Marathon Uni Mill, which is motor-driven. "I couldn't believe my eyes the first time I tried the Marathon," Diana says. "I opened the stones to 1/8th inch, and out came a bin full of whole kernels and hulls split right at the seams. What a thrill that was!"She found that by starting at the widest setting,and gradually narrowing the opening, almost every seed was dehulled. The stones crack the hulls open, then rub them to encourage the seed away from the fibrous lining. The Bell hand mill worked almost as well. "As long as the stones open at least as wide as the widest unhulled seed, any mill will work," she says.Because the seed slips through the mill on its flat side, grading is an important step to take before dehulling. We made three sizing boxes. Thefirst is 1/4-inch hardware cloth [wire screen]. The second is two layers of1/4-inch cloth, moved slightly apart to narrow the opening in one direction, and the third is two layers of screen adjusted to make a still-smaller opening. Since the smallest unhulled seeds are about the size of the largest hulled kernels, the grading step prevents these undersized seeds from passing through unhulled. Processed together at a closer setting, the smallest seeds hulled out.Jim Eldon's workshop is littered with strange-looking pieces of apparatus. They represent initial attempts to build a workable winnowing box, using Kormier's vacuum exhaust idea for a source of air. Jim, Fred Matlack and Diana finally made a box with a Plexiglas front, through which they could observe what was happening.They cut a hole in the back of the box with a sliding cover to regulate the air pressure, and fiddled with various arrangements of baffles. The result was a stream of hulls exiting through one hole while the kernels fell to the bottom of the box. Now they were ready to try a five-pound sample of unhulled sunflower seeds to see how much they could recover.The five pounds were graded and dehulled, then winnowed. We got about one hull for every ten kernels in the final, winnowed product. These are easily picked out. They usually contain kernels still held behind the fibrous strings of the hull. Their weight prevents them from blowing out with the empty hulls. We found that bug-eaten seeds do blow away with the chaff, which was a bonus for cleanliness of the final product. Toss the hulls to the birds, who will find broken seeds among them.Starting with 80 ounces of unhulled seed, we ended up with 41-1/4 ounces of edible whole seeds, 1.8 ounces of damaged seeds suitable for animal feed, and 36.6 ounces of hulls. It took us about an hour. Notbad.Sunflower seeds store perfectly in the hulls, but they deteriorate more rapidly when shelled out. The grain mill dehuller and winnowing box give the gardener a way to have the freshest possible seeds for eating at all times of the year. With the construction of one more piece of equipment -- the oil press -- he can have absolutely fresh, unrefined, polyunsaturated sunflower oil for salads, mayonnaise and cooking.Most light, refined vegetable oils have been extracted using hexane, a form of naphtha. The oil is then heated to boil off the hexane. Lye is dumped into it. It's washed with steam, then heated to remove odors and taste before being laced with preservatives and stabilizers. It may feel oily in the mouth, but you might as well taste air. No so with fresh-made sunflower oil -- it's deliciously yet subtly nutty in flavor, adding unsurpassed flavor to salads.There's good reason to believe that sunflower oil may become the #1 vegetable oil in the U.S. in a few years. It's already #1 in health-conscious Europe. Corn oil has already caught on here for health reasons, and sunflower oil is so much better. Sunflower oil's 70 percent polyunsaturate is just under safflower, with corn oil bringing up the rear with 55 percent. And sunflowers yield 40 percent oil, soybeans only 20 percent.Our oil press isrelatively simple, but it must be welded together. Check the construction directions for details. The press consists of a welded tubular frame which accepts a three-ton hydraulic jack. You may already have one. If not, it can be purchased at most auto and hardware stores for about $16. A metal canister with holes drilled in its sides and one end welded shut holds the mashed sunflower seeds. A piston is inserted in the canister and then inverted and slipped over a pedestal on the frame. The jack is set in place, and the pressure gradually increased over half an hour. The oil drips from the sides of the canister into a tray -- the bottom of a plastic jug slipped over the pedestal works fine -- which empties the oil into a cup. You can filter the oil with a coffee filter to remove pieces of seed and other fine particles that would burn if the oil were used for cooking. If it's for salads or mayonnaise, there's no need to filter it.We first tried using "confectionary" sunflower seeds for oil. These are the regular eating kernels we're used to seeing. They give less than half as much oil as the oilseed types of sunflower. Although you can use confectionary types such as MAMMOTH RUS- SIAN for oil, don't expect to get more than an ounce and a half from a pound of seed. Oilseed produces three or more ounces of oil from a pound of seed and is well worth planting along with confectionary-type seeds. Oilseed has another big advantage -- to prepare it, you can put the whole, unhulled seed into a blender and whiz it until it forms a fine meal, while confectionary seeds must be dehulled first. The entire sequence of grading, dehulling and winnowing is avoided with oilseed.Oil types produce about a tenth of a pound of seed per head in commercial production. Gardeners, with their better soil and care, invariably do better than that. Our conservative estimate is that 1,280 plants will be enough for three gallons of oil. Spaced one foot apart in rows two feet apart, 1,280 oilseed plants will take a space 40-by-56 feet, or 80-by-28 if you want a more rectangular patch to face south.We worked in pound batches, since the canister just holds one pound of mash. After blending, we heated it to 170 degrees F. (77 deg C) by placing it in a 300-degree F. (149 deg C) oven and stirring it every five minutes for 20 minutes. Heating gets the oil flowing and doubles the yield of oil. In case you're wondering,"cold-pressed" oils sold commercially are also heated, and some are subjected to the entire chemical process. The term has no firm meaning within the industry, according to the literature we've surveyed.Heating does not change the structure of fats. It will not turn polyunsaturated fats into saturated fats. In fact, Dr. Donald R. Germann in his book, "TheAnti-Cancer Diet", says that "... an unsaturated fat must be heated to high temperatures -- above 425 degrees F. or 200 degrees C. -- at least 8 or 10 times before any shift toward saturation occurs..." Dean C. Fletcher, Ph.D., of the American Medical Association Department of Foods and Nutrition in Chicago, says, "It's true that either high temperature or repeated heatingdoes change the nature of some of the unsaturated oil molecules. (But) the flavor of the oil changes as these chemical changes occur, spoiling its taste. This effect is probably more profound than any of the physiological changes the altered oil might produce within the body."From 500 gm. of heated mash, we pressed 89 gm. of oil, 89 percent of the entire amount available and twice as much as we could press from unheated oil! The decision is up to you whether or not to heat the mash, but that extra 50 percent seems like an awful lot, especially when the whole technique is so labor intensive. The oil should be stored in the refrigerator, and it's probably best to use it within a month, since it has no preservatives. Mayonnaise made with such fresh oils should be kept refrigerated and used within two weeks. The leftover cake, still containing 50 percent of its oil, is a nutritious addition to your dishes, and makes excellent feed for animals or winter birds. Store the pressed cake in the freezer.We're talking then about a sunflower patch with two kinds of plants -- confectionary such as MAMMOTH RUSSIAN and oilseed such as PEREDOVIK. The oilseed plants should be grown 12 inches apart in rows two feet apart. Four average confectionary heads yield about a pound of unhulled seed. You'll need about 35 pounds of unhulled seed, or 140plants-worth, to yield 20 pounds of hulled kernels, about what a family of four will use in a year. That many plants can be grown in an area 26-by-10 feet. That's 260 square feet. Put that together with the 2,240 square feet for the oilseed sunflowers, and you need a patch about 2,500 square feet -- 25 100-foot rows -- to keep yourself supplied year-round with super nutrition and unsurpassable taste.Winnowing Machine For Sunflower SeedsThe winnowing machine operates on the age-old principle of blowing the chaff away from the heavy grain with a controlled current of air.The unit uses a household or shop-type vacuum cleaner for its air supply. A vacuum cleaner was used as a power source because it can supply a large volume of air over an extended period of time, and most homes and farms have a vacuum cleaner.A cloth bag has been attached to the chaff chute to catch the chaff as it is separated from the seed. The bag allows the hulls to be collected and greatly reduces the amount of waste material normally blown into the air by conventional systems.The unit has been constructed in such a way that the cloth bag and cleaner box can be placed inside the seed box, making a compact package for storage.Tools Required1. Table Saw2. Drill Press3. Band Saw4. Saber SawProcedure (cleaner box)1 . Cut out the two sides of the cleaner box from 1/4-inch plywood.2. Cut out the six interior pieces of the cleaner box from 3/4 x 3-1/2-inch select pine.3. Assemble the cleaner box elements with glue and nails.4. Cut four 1/4-inch square strips of pine four inches long.5. Glue the strips around the end of the chaff chute.6. Sand all surfaces and edges.7. Finish with clear lacquer finish.Procedure (seed box)1. Cut two pieces of pine /34" x 5 /12 x 15 inches for the sides.2. Cut two pieces of pine 3/4 x 5-1/2 x inches for the top and bottom.3. Plow a /14 x 1/4 groove for the front and back panels in all four pieces.4. Rip the top board to 5 inches so that the front panel can slide into the grooves in the side boards.5. Rabbet both ends of each 15-inch side piece to accept the top and bottom boards.6. Drill a hole in the left side board 2-1/2 inches from the top. The size of the hole is determined by the vacuum cleaner hose fitting.7. Cut a 3-1/4 x 4 inch hole in the top 1/2 inch from the right end. This hole will accept the cleaner box.8. Cut two pieces of pine for the baffle.9. Drill two 1-inch holes in the bottom of the baffle box.10. Cut a piece of 1/4 x 8-1/2 x 14 inch plywood for the back panel.11. Cut a 3-inch hole, centered 1-7/8 inches from the top and left sides of the plywood back.12. Assemble the sides, baffles, top, bottom, and back panel with glue and nails.13. Cut an 8-7/16 x 15-3/4-inch piece of Plexiglas for the front.14. Cut a one-inch radius on the top corners of the front.and sand the edges.15. Drill a one-inch thumb hole centered 7/8 inch from the top edge.16. Cut a 3-1/2-inch disk of 1/4-inch plywood for the vent cover.17. Drill a 3/16-inch hole 3/8 inch from the edge of the disk.18. Mount the disk over the vent with a #10 x 1-inch screw.19. Sand all surfaces and edges of the, box.20. Finish with clear lacquer finish.MaterialsCleaner Box2 -- 7-3/4 x 7-1/2 x 3/4" plywood (sides)6 -- 3/4 x 3-1/2 x 24" for all members (baffles)4 -- 1/4 x 1/4 x 4" pine (chute cleats)22 -- 1" x 18 ga. headed nailsWhite vinyl glueClear lacquer finishSeed Box2 -- 3/4' x 5-1/2 x 15" select pine (sides)2 -- 3/4 x 5-1/2 x 8-1/2" select pine (top and bottom)1 -- 3/4 x 3-1/2 x 4-1/2" select pine (baffle)1 -- 3/4 x 4-1/2 x 4-1/2" select pine (baffle)1 -- 1/4 x 8-1/2 x 14" plywood (back)1 -- 1/4 x 3-1/2" dia. plywood (control valve)1 -- 1/4' x 8-7/16 x 15-1/4" Plexiglas (front)1 - #10 x 1" flat head screw18 - 4d finish nailsWhite vinyl glueClear lacquer finish1 -- 17 x 31" cloth laundry bagSunflower Seed Oil PressThe press was designed so that homesteaders can produce sunflower oil from their own seeds. The oil can be pressed as is or heated to 170 degrees F., which doubles oil yield.Both methods require the seed to be ground to fine powder. If you are pressing the oil seed variety, a meat grinder or electric blender will do an excellent job of grinding the seed. The confectionary type of seed will require the seed to be hulled and winnowed before it is ground. A food mill with the stones set at the coarse setting can be used to accomplish this step. The ground kernels are placed in the cylinder with the piston closing the bottom portion of the cylinder.The cylinder is mounted in the press frame and a three-ton hydraulic jack is used to supply the pressure.Because of the great pressures created by the hydraulic jack, it is important that the frame be properly constructed and firmly mounted to the work surface before the pressing operation begins. The following instructions can be given to a welder.Tools Required1. Power Hacksaw2. Metal Band Saw3. Metal Lathe4. Drill Press5. Belt or Disk Grinder6. Arc Welder7. Hand ClampsProcedure (Frame)1. Cut two pieces of 1-3/4" O.D. x 1-3/8" I.D. x 24-1/2 inch long tubing for the uprights.2. Cut one piece of 1-3/4" O.D. x 1-3/8" I.D. x 6-1/2 inch long tubing for the center tube.3. Cut one 3/4" x 2-3/4 x 5-1/2 inch steel bar for the top cross member.4. Cut two pieces of 1-3/4 x 1-3/4 x 8 inch angle iron for the base members.5. Drill two 9/32-inch holes in each base member 1/2 inch from the outer edges.6. Weld the base members, tubes and cross member together as per the drawing.7. Grind all edges to remove any burrs.8. Paint the frame.9. If a mounting board is desired, cut a piece of pine 1-1/4 x 6-1/2 x 12 inches long.10. Center the frame on the board and mark the location of the four mounting holes.11. Drill four 7/8-inch holes 1/4-inch deep to accept the T-nuts.12. Drill four 5/16-inch holes through the mounting board using the same centers created by the 7/8-inch holes.13. Round the edges of the base and sand all surfaces.14. Install four 1/4-20 T-nuts.15. Finish the base with clear lacquer finish.16. Assemble the base to the frame using four 1/4-20 x 1-1/4-inch round head bolts.Procedure (Cylinder)1. Cut a piece of 3-1/2" O.D. x 3-1/4" I.D. tubing 5-3/8 inches long.2. Face both ends on the lathe.3. Cut out a 3-1/2-inch round disk from 1/4-inch plate steel.4. Weld the disk to one end of the tube.5. Drill a series of 3/32-inch holes around the side of the tube on 1/2-inch centers.6. Remove all burrs on the inside and outside of the tube.Procedure (Piston)1. Cut out a 3-3/8-inch disk of 1/4-inch plate steel.2. Cut a 1-3/8" O.D. x 1-1/8" I.D. piece of tubing 1-1/8 inches long.3. Face both ends of the tube.4. Weld the tube in the center of the 3-3/8-inch disk. All welds should be made on the inside of the tube.5. Mount the piston in the lathe and turn the disk to fit the inside diameter of the cylinder. This will be about 3-15/64 inches in diameter.6. Remove any sharp edges.Procedure (Collector Ring)1. Cut the bottom out of a one-gallon plastic bottle. The cut line should be approximately 1-1/2 inches from the bottom of the bottle.2. Make a 1/8 x 1 inch slot at one edge of the bottom outside ring. This will allow the oil to pour into a receiving cup.3. Cut a 1-3/4-inch hole in the center of the bottom, so that the unit will fit over the center tube in the frame.MaterialsFrame2 -- 1-3/4 O.D. x 1-3/8 I.D. x 24-1/2" long H.R.S. (frame tubes)1 -- 1-3/4 O.D. x 1-3/8 I.D. x 6-1/2 inch long H.R.S. (center tube)1 -- 3/4 x 2-3/4 x 5-1/2" flat bar H.R.S. (top cross member)2 -- 1-3/4 x 1-3/4 x 8" angle iron H.R.S. (base members)1 -- 1-1/4 x 6-1/2 x 12" #2 white pine (wood base)4 -- 1/4-20 x 1-1/4 R.H. mounting bolts4 -- 1/4-20 T-nutsBlack enamel for frame (finishing material)Clear lacquer finish for wood base3 -- 1/8" dia. welding rodsCylinder1 -- 1/4 x 3-1/2" dia. C.R.S. disk (top)1 -- 3-1/2 O.D. x 3-1/4 I.D. C.R.S. tube (cylinder)1 -- 1/8 dia. welding rodPiston1 -- 1/4 x 3-3/8 D.A. C.R.S. disk (piston top)1 -- 1-1/4 O.D. x 1 I.D. x 1" long H.R.S. (piston tube)1 -- 1/8 dia. welding rodCollector Ring1 -- Bottom from a one-gallon plastic bottle (oil collector ring)葵花籽脱壳机和油压机由Jeff考克斯-从有机园艺，1979年4月，罗代尔新闻2,500平方尺，一个四口之家每年可以长到足以产生三种葵花籽国产蔬菜沙拉或烹调油和20磅的营养丰富，适合脱皮加仑种子 - 与遗留养活一个冬天的产值，破碎的种子鸟类。
机械设计制造及其自动化专业外文翻译--机器人
外文原文RobotsThe industrial robot is used in the manufacturing environment to increase productivity . It can be used to do routine and tedious assembly line jobs , or it can perform jobs that might be hazardous to do routine and tedious assembly line jobs , or it can perform jobs that might be hazardous to the human worker . For example , one of the first industrial robots was used to replace the nuclear fuel rods in nuclear power plants . A human doing this job might be exposed to harmful amounts of radiation . The industrial robot can also operate on the assembly line , putting together small components , such as placing electronic components on a printed circuit board . Thus , the human worker can be relieved of the routine operation of this tedious task . Robots can also be programmed to defuse bombs , to serve the handicapped , and to perform functions in numerous applications in our society .The robot can be thought of as a machine that will move an end-of-arm tool , sensor , and gripper to a preprogrammed location . When the robot arrives at this location , it will perform some sort of task . This task could be welding , sealing , machine loading , machine unloading , or a host of assembly jobs . Generally , this work can be accomplished without the involvement of a human being , except for programming and for turning the system on and off .The basic terminology of robotic systems is introduced in the following :1. A robot is a reprogrammable , multifunctional manipulator designed to move parts , materials , tools , or special devices through variable programmed motions for the performance of a variety of different task . This basic definition leads to other definitions , presented in the following paragraphs , that give a complete picture of a robotic system .2. Preprogrammed locations are paths that the robot must follow to accomplish work . At some of these locations , the robot will stop and perform some operation , such as assembly of parts , spray painting , or welding . These preprogrammed locations are stored in the robot’s memory and are recalled later for continuous operation . Furthermore , these preprogrammed locations , as well as other program data , can be changed later as the work requirements change . Thus , with regard to this programming feature , an industrial robot is very much like a computer , where data can be stored and later recalled and edited .3. The manipulator is the arm of the robot . It allows the robot to bend , reach ,and twist . This movement is provided by the mani pulator’s axes , also called the degrees of freedom of the robot . A robot can have from 3 to 16 axes . The term degrees of freedom of freedom will always relate to the number of axes found on a robot .4. The tooling and grippers are not part of the robotic system itself ; rather , they are attachments that fit on the end of the robot’s arm . These attachments connected to the end of the robot’s arm allow the robot to lift parts , spot-weld , paint , arc-weld , drill , deburr , and do a variety of tasks , depending on what is required of the robot .5. The robotic system can also control the work cell of the operating robot . the work cell of the robot is the total environment in which the robot must perform its task . Included within this cell may be the controller , the robot manipulator , a work table , safety features , or a conveyor . All the equipment that is required in order for the robot to do its job is included in the work cell . In addition , signals from outside devices can communicate with the robot in order to tell the robot when it should assemble parts , pick up parts , or unload parts to a conveyor .The robotic system has three basic components : the manipulator , the controller , and the power source .A . ManipulatorThe manipulator , which does the physical work of the robotic system , consists of two sections : the mechanical section and the attached appendage . The manipulator also has a base to which the appendages are attached . Fig.1 illustrates the connection of the base and the appendage of a robot .The base of the manipulator is usually fixed to the floor of the work area . Sometimes , though , the base may be movable . In this case , the base is attached to either a rail or a track , allowing the manipulator to be moved from one location to another .As mentioned previously , the appendage extends from the base of the robot . The appendage is the arm of the robot . It can be either a straight , movable arm or a jointed arm . the jointed arm is also known as an articulated arm .The appendages of the robot manipulator give the manipulator its various axes of motion . These axes are attached to a fixed base , which , in turn , is secured to a mounting . This mounting ensures that the manipulator will remain in one location。
机械设计制造及其自动化 英文
机械设计制造及其自动化英文Mechanical Design, Manufacturing and AutomationMechanical design, manufacturing, and automation are essential components of the modern industrial economy. These fields encompass the creation and production of a wide variety of products, from consumer goods to high-tech machinery.In mechanical design, engineers utilize computer-aided design (CAD) software to develop and optimize the design of mechanical components and systems. This allows for the creation of precise and efficient designs that can be easily modified and tested before production begins.Once the design phase is complete, manufacturing processes take over to bring the design to life. This involves a combination of traditional machining techniques and advanced manufacturing technologies such as 3D printing and robotic assembly. The goal of manufacturing is to efficiently produce high-quality products at scale, while minimizing waste and cost.Automation plays a crucial role in both the design and manufacturing phases. Automated systems and robotics are widely used to streamline production processes, increase precision, and improve overall efficiency. This can include automated assembly lines, robotic machining, and computer-controlled quality control systems.Overall, the integration of mechanical design, manufacturing, and automation has revolutionized the way products are created andproduced. By leveraging the latest technologies and technical expertise, businesses are able to innovate and bring new productsto market more quickly and efficiently than ever before.当今的机械设计、制造和自动化技术也在不断创新。
机械加工外文翻译、中英文翻译、机械类外文文献翻译
机械加工外文翻译、中英文翻译、机械类外文文献翻译The engine lathe is an old but still useful metal removal machine with many desirable attributes。
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turret lathes。
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it largely depends on the skill of the operator。
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it is XXX.XXX cutting tools。
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it is most cost-effective to use a XXX。
designers should aim to minimize the number of ns required.Another n for n XXX。
机械类外文文献翻译(中英文翻译)
机械类外文文献翻译(中英文翻译)英文原文Mechanical Design and Manufacturing ProcessesMechanical design is the application of science and technology to devise new or improved products for the purpose of satisfying human needs. It is a vast field of engineering technology which not only concerns itself with the original conception of the product in terms of its size, shape and construction details, but also considers the various factors involved in the manufacture, marketing and use of the product.People who perform the various functions of mechanical design are typically called designers, or design engineers. Mechanical design is basically a creative activity. However, in addition to being innovative, a design engineer must also have a solid background in the areas of mechanical drawing, kinematics, dynamics, materials engineering, strength of materials and manufacturing processes.As stated previously, the purpose of mechanical design is to produce a product which will serve a need for man. Inventions, discoveries and scientific knowledge by themselves do not necessarily benefit people; only if they are incorporated into a designed product will a benefit be derived. It should be recognized, therefore, that a human need must be identified before a particular product is designed.Mechanical design should be considered to be an opportunity to use innovative talents to envision a design of a product, to analyze the systemand then make sound judgments on how the product is to be manufactured. It is important to understand the fundamentals of engineering rather than memorize mere facts and equations. There are no facts or equations which alone can be used to provide all the correct decisions required to produce a good design.On the other hand, any calculations made must be done with the utmost care and precision. For example, if a decimal point is misplaced, an otherwise acceptable design may not function.Good designs require trying new ideas and being willing to take a certain amount of risk, knowing that if the new idea does not work the existing method can be reinstated. Thus a designer must have patience, since there is no assurance of success for the time and effort expended. Creating a completely new design generally requires that many old and well-established methods be thrust aside. This is not easy since many people cling to familiar ideas, techniques and attitudes. A design engineer should constantly search for ways to improve an existing product and must decide what old, proven concepts should be used and what new, untried ideas should be incorporated.New designs generally have "bugs" or unforeseen problems which must be worked out before the superior characteristics of the new designs can be enjoyed. Thus there is a chance for a superior product, but only at higher risk. It should be emphasized that, if a design does not warrant radical new methods, such methods should not be applied merely for the sake of change.During the beginning stages of design, creativity should be allowedto flourish without a great number of constraints. Even though many impractical ideas may arise, it is usually easy to eliminate them in the early stages of design before firm details are required by manufacturing. In this way, innovative ideas are not inhibited. Quite often, more than one design is developed, up to the point where they can be compared against each other. It is entirely possible that the design which is ultimately accepted will use ideas existing in one of the rejected designs that did not show as much overall promise.Psychologists frequently talk about trying to fit people to the machines they operate. It is essentially the responsibility of the design engineer to strive to fit machines to people. This is not an easy task, since there is really no average person for which certain operating dimensions and procedures are optimum.Another important point which should be recognized is that a design engineer must be able to communicate ideas to other people if they are to be incorporated. Communicating the design to others is the final, vital step in the design process. Undoubtedly many great designs, inventions, and creative works have been lost to mankind simply because the originators were unable or unwilling to explain their accomplishments to others. Presentation is a selling job. The engineer, when presenting a new solution to administrative, management, or supervisory persons, is attempting to sell or to prove to them that this solution is a better one. Unless this can be done successfully, the time and effort spent on obtaining the solution have been largely wasted.Basically, there are only three means of communication available tous. These are the written, the oral, and the graphical forms. Therefore the successful engineer will be technically competent and versatile in all three forms of communication. A technically competent person who lacks ability in any one of these forms is severely handicapped. If ability in all three forms is lacking, no one will ever know how competent that person is!The competent engineer should not be afraid of the possibility of not succeeding in a presentation. In fact, occasional failure should be expected because failure or criticism seems to accompany every really creative idea. There is a great deal to be learned from a failure, and the greatest gains are obtained by those willing to risk defeat. In the final analysis, the real failure would lie in deciding not to make the presentation at all. To communicate effectively, the following questions must be answered:(1) Does the design really serve a human need?(2) Will it be competitive with existing products of rival companies?(3) Is it economical to produce?(4) Can it be readily maintained?(5) Will it sell and make a profit?Only time will provide the true answers to the preceding questions, but the product should be designed, manufactured and marketed only with initial affirmative answers. The design engineer also must communicate the finalized design to manufacturing through the use of detail and assembly drawings.Quite often, a problem will occur during the manufacturing cycle [3].It may be that a change is required in the dimensioning or tolerancing of a part so that it can be more readily produced. This fails in the category of engineering changes which must be approved by the design engineer so that the product function will not be adversely affected. In other cases, a deficiency in the design may appear during assembly or testing just prior to shipping. These realities simply bear out the fact that design is a living process. There is always a better way to do it and the designer should constantly strive towards finding that better way.Designing starts with a need, real or imagined. Existing apparatus may need improvements in durability, efficiently, weight, speed, or cost. New apparatus may be needed to perform a function previously done by men, such as computation, assembly, or servicing. With the objective wholly or partly defined, the next step in design is the conception of mechanisms and their arrangements that will perform the needed functions.For this, freehand sketching is of great value, not only as a record of one's thoughts and as an aid in discussion with others, but particularly for communication with one's own mind, as a stimulant for creative ideas.When the general shape and a few dimensions of the several components become apparent, analysis can begin in earnest. The analysis will have as its objective satisfactory or superior performance, plus safety and durability with minimum weight, and a competitive east. Optimum proportions and dimensions will be sought for each critically loaded section, together with a balance between the strength of the several components. Materials and their treatment will be chosen. These important objectives can be attained only by analysis based upon the principles ofmechanics, such as those of statics for reaction forces and for the optimumutilization of friction; of dynamics for inertia, acceleration, and energy; of elasticity and strength of materials for stress。
机床——机械类外文文献翻译、中英文翻译
毕业设计(论文)外文资料翻译系部：专业：姓名：学号：外文出处：English For Electromechanical(用外文写)Engineering附件：1.外文资料翻译译文；2.外文原文。
附件1：外文资料翻译译文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。
机械设计制造论文外文翻译(中文有期刊号)英文原文已发
潍坊学院学生毕业设计外文译文专业机械设计制造及其自动化班级08级机制本4学生姓名耿传锋学号08012130450学生成绩机电与车辆工程学院译文要求1.外文翻译必须使用钢笔，手工工整书写，或用A4纸打印。
2.所选的原文内容必须与课题或专业方向紧密相关，注明详细出处。
3.外文翻译书文本后附原文（或复印件），译文不少于3000字符。
译文评阅评阅要求：应根据学校“译文要求”，对学生译文的准确性、翻译数量以及译文的文字表述情况等作具体的评价。
指导教师评语：指导教师签名年月日分析模型导轨磨损的演算对机床加工精度的影响工程系副教授伊沃娜彼得，凯特林大学,工程系博士讲师卡门波帕，凯特林大学，工程系博士讲师杜米特鲁，凯特林大学，工程系西普里安，凯特林大学摘要：机床导轨磨损影响积极震动。
最初的刀具运动轨迹作为导轨磨损的结果，将被修改，尺寸精度产生差异的工件的几何形状和偏差。
因为它已经成为连接称为移动和刚性导轨的磨损取决于许多参数（压力，速度，长度摩擦，润滑，材料）。
一种或另一种分析模型和/或磨损的实验模型的选择取决于所的工作条件，假设被称为耦合材料。
目前的工作的目标是建立一个分析模型的演算显示导轨的影响磨损在工具机的加工精度。
关键词：精度机床表面。
1、简介因为它已经被称为加工精度取决于每一块技术系统（机床，夹紧装置，刀具等）[1，2，3]连接到多种因素。
在目前的工作，笔者的目标是建立规模和影响力的床身在对车床使用的机床的加工精度，导轨的磨损。
导轨的大小和（纵向）滑动磨损是重要的被称为因为滑动轨迹，由于磨损，时间条件下发生的尺寸偏差和加工零件的表面质量的变化。
以建立系统的床身滑动磨损大小，三种不同的情况正在分析：1 - 床身导轨正在磨损2 - 导轨只被磨损3 - 导轨（床身滑动）正在磨损2、建立床身滑动产生的误差分析模型磨损为了建立在加工的磨损过程的定量影响车床的精度，以下假设[2]：- 被认为是在一定的刚性指南U（X）的磨损轮廓曲线时刻评估应力循环的数量;- 比以前所有的周期产生的磨损，被忽视的电流应力周期的磨损;- 移动导轨磨损U1（L）是这样产生的，该导轨的性能如下；不断刚性指南轮廓;基于这个假设，它是承认接触的类型始终是按照正常和切向应力的适当分配;- 移动导轨位移在两个剖面的接触面，使正常的线是独一无二的刚性;- 磨损是一个连续的过程和特点是由连续拖到指导长度的功能和时间的考虑，磨损层的厚度。
机械设计制造及其自动化毕业论文中英文资料外文翻译
机械设计创造及其自动化毕业论文外文文献翻译INTEGRATION OF MACHINERY译文题目专业机械设计创造及其自动化外文资料翻译INTEGRATION OF MACHINERY（From ELECTRICAL AND MACHINERY INDUSTRY）ABSTRACTMachinery was the modern science and technology development inevitable result, this article has summarized the integration of machinery technology basic outline and the development background .Summarized the domestic and foreign integration of machinery technology present situation, has analyzed the integration of machinery technology trend of development.Key word： integration of machinery ，technology， present situation ，product t，echnique of manufacture ，trend of development0. Introduction modern science and technology unceasing development, impelled different discipline intersecting enormously with the seepage, has caused the project domain technological revolution and the transformation .In mechanical engineering domain, because the microelectronic technology and the computer technology rapid development and forms to the mechanical industry seepage the integration of machinery, caused the mechanical industry the technical structure, the product organization, the function and the constitution, the production method and the management systemof by machinery for the characteristic integration ofdevelopment phase.1. Integration of machinery outline integration of machinery is refers in the organization new owner function, the power function, in the information processing function and the control function introduces the electronic technology, unifies the system the mechanism and the computerization design and the software which constitutes always to call. The integration of machinery development also has become one to have until now own system new discipline, not only develops along with the science and technology, but also entrusts with the new content .But its basic characteristic may summarize is: The integration of machinery is embarks from the system viewpoint, synthesis community technologies and so on utilization mechanical technology, microelectronic technology, automatic control technology, computer technology, information technology, sensing observation and control technology, electric power electronic technology, connection technology, information conversion technology as well as software programming technology, according to the system function goal and the optimized organization goal, reasonable disposition and the layout various functions unit, in multi-purpose, high grade, redundant reliable, in the low energy consumption significance realize the specific function value, and causes the overall system optimization the systems engineering technology .From this produces functional system, then becomes an integration of machinery systematic or the integration of machinery product. Therefore, of coveringtechnology is based on the above community technology organic fusion one kind of comprehensive technology, but is not mechanical technical, the microelectronic technology as well as other new technical simple combination, pieces together .This is the integration of machinery and the machinery adds the machinery electrification which the electricity forms in the concept basic difference .The mechanical engineering technology has the merely technical to develop the machinery electrification, still was the traditional machinery, its main function still was replaces with the enlargement physical strength .But after develops the integration of machinery, micro electron installment besides may substitute for certain mechanical parts the original function, but also can entrust with many new functions,like the automatic detection, the automatic reduction information, demonstrate the record, the automatic control and the control automatic diagnosis and the protection automatically and so on .Not only namely the integration of machinery product is human's hand and body extending, human's sense organ and the brains look, has the intellectualized characteristic is the integration of machinery and the machinery electrification distinguishes in the function essence.2. Integration of machinery development condition integration of machinery development may divide into 3 stages roughly.20th century 60's before for the first stage, this stage is called the initial stage .In this time, the people determination not on own initiative uses the electronic technology the preliminary achievement to consummate the mechanical product the performance .Specially in Second World War period, the war has stimulated the mechanical product and the electronic technology union, these mechanical and electrical union military technology, postwar transfers civilly, to postwar economical restoration positive function .Developed and the development at that time generally speaking also is at the spontaneouscondition .Because at that time the electronic technology development not yet achieved certain level, mechanical technical and electronic technology union also not impossible widespread and thorough development, already developed the product was also unable to promote massively. The 20th century 70~80 ages for the second stage, may be called the vigorous development stage .This time, the computer technology, the control technology, the communication development, has laid the technology base for the integration of machinery development . Large-scale, ultra large scale integrated circuit and microcomputer swift and violent development, has provided the full material base for the integration of machinery development .This time characteristic is :①A mechatronics word first generally is accepted in Japan, probably obtains the quite widespread acknowledgment to 1980s last stages in the worldwide scale ;②The integration of machinery technology and the product obtained the enormous development ;③The various countries start to the integration of machinery technology and the product give the very big attention and the support. 1990s later periods, started the integration of machinery technology the new stagewhich makes great strides forward to the intellectualized direction, the integration of machinery enters the thorough development time .At the same time, optics, the communication and so on entered the integration of machinery, processes the technology also zhan to appear tiny in the integration of machinery the foot, appeared the light integration of machinery and the micro integration of machinery and so on the new branch; On the other hand to the integration of machinery system modeling design, the analysis and the integrated method, the integration of machinery discipline system and the trend of development has all conducted the thorough research .At the same time, because the hugeprogress which domains and so on artificial intelligence technology, neural network technology and optical fiber technology obtain, opened the development vast world for the integration of machinery technology .These research, will urge the integration of machinery further to establish the integrity the foundation and forms the integrity gradually the scientific system. Our country is only then starts from the beginning of 1980s in this aspect to study with the application .The State Councilsummary had considered fully on international the influence which and possibly brought from this about the integration of machinery technology developmenttrend .Many universities, colleges and institutes, the development facility and some large and middle scale enterprises have done the massive work to this technical development and the application, does not yield certain result, but and so on the advanced countries compared with Japan still has the suitable disparity.3. Integration of machinery trend of development integrations of machinery are the collection machinery, the electron, optics, the control, the computer, the information and so on the multi-disciplinary overlapping syntheses, its development and the progress rely on and promote the correlation technology development and the progress .Therefore, the integration of machinery main development direction is as follows:3.1 Intellectualized intellectualizations are 21st century integration of machinery technological development important development directions .Theartificial intelligence obtains day by day in the integration of machinery constructor's research takes, the robot and the numerical control engine bedis to the machine behavior description, is in the control theory foundation, the absorption artificial intelligence, the operations research, the computer science, the fuzzy mathematics, the psychology, the physiology and the chaos dynamics and so on the new thought, the new method, simulate the human intelligence, enable it to have abilities and so on judgment inference, logical thinking, independent decision-making, obtains the higher control goal in order to .Indeed, enable the integration of machinery product to have with the human identical intelligence, is not impossible, also is nonessential .But, the high performance, the high speed microprocessor enable the integration of machinery product to have preliminary intelligent or human's partial intelligences, then is completely possible and essential.In the modern manufacture process, the information has become the control manufacture industry the determining factor, moreover is the most active actuation factor .Enhances the manufacture system information-handling capacity to become the modern manufacture science development a key point .As a result of the manufacture system information organization and structure multi-level, makes the information the gain, the integration and the fusion presents draws up the character, information measure multi-dimensional, as well as information organization's multi-level .In the manufacture information structural model, manufacture information uniform restraint, dissemination processing and magnanimous data aspects and so on manufacture knowledge library management, all also wait for further break through.Each kind of artificial intelligence tool and the computation intelligence method promoted the manufacture intelligence development in the manufacture widespread application .A kind based on the biological evolution algorithm computation intelligent agent, in includes thescheduling problem in the combination optimization solution area of technology, receives the more and more universal attention, hopefully completes the combination optimization question when the manufacture the solution speed and the solution precision aspect breaks through the question scale in pairs the restriction .The manufacture intelligence also displays in: The intelligent dispatch, the intelligent design, the intelligent processing, the robot study, the intelligent control, the intelligent craft plan, the intelligent diagnosis and so on are various These question key breakthrough, may form the product innovation the basic research system. Between 2 modern mechanical engineering front science different science overlapping fusion will have the new science accumulation, the economical development and society's progress has had the new request and the expectation to the science and technology, thus will form the front science .The front science also has solved and between the solution scientific question border area .The front science has the obvious time domain, the domain and the dynamic characteristic .The project front science distinguished in the general basic science important characteristic is it has covered the key science and technology question which the project actual appeared.Manufacture system is a complex large-scale system, for satisfies the manufacture system agility, the fast response and fast reorganization ability, must profit from the information science, the life sciences and the social sciences and so on the multi-disciplinary research results, the exploration manufacture system new architecture, the manufacture pattern and the manufacture system effective operational mechanism .Makes the system optimization the organizational structure and the good movement condition is makes the system modeling , the simulation and the optimized essential target .Not only the manufacture system new architecture to makes the enterprise the agility and may reorganize ability to the demand response ability to have the vital significance, moreover to made the enterprise first floor production equipment the flexibility and may dynamic reorganization ability set a higher request .The biological manufacture view more and more many is introduced the manufacture system, satisfies the manufacture system new request.The study organizes and circulates method and technique of complicated system from the biological phenomenon, is a valid exit which will solve many hard nut to cracks that manufacturing industry face from now on currently .Imitating to living what manufacturing point is mimicry living creature organ of from the organization, from match more, from growth with from evolution etc. function structure and circulate mode of a kind of manufacturing system and manufacturing process.The manufacturing drives in the mechanism under, continuously by one's own perfect raise on organizing structure and circulating mode and thus to adapt the process of[with] ability for the environment .For from descend but the last product proceed together a design and make a craft rules the auto of the distance born, produce system of dynamic state reorganization and product and manufacturing the system tend automatically excellent provided theories foundation and carry out acondition .Imitate to living a manufacturing to belong to manufacturing science and life science of"the far good luck is miscellaneous to hand over", it will produce to the manufacturing industry for 21 centuries huge of influence .机电一体化摘要机电一体化是现代科学技术发展的必然结果,本文简述了机电一体化技术的基本概要和发展背景。
机械专业毕业设计外文翻译相关外文文献
A new driver based on dual-mode frequency and phase control for traveling-wave type ultrasonic motorTien-Chi Chen a,*,Chih-Hsien Yu a ,Mi-Ching Tsai ba Department of Engineering Science,National Cheng Kung University,Tainan,Taiwan bDepartment of Mechanical Engineering,National Cheng Kung University,Tainan,Taiwana r t i c l e i n f o Article history:Received 6August 2007Accepted 24March 2008Available online 12May 2008Keywords:Ultrasonic motorFrequency and phase modulation controla b s t r a c tA mode conversion rotary traveling-wave ultrasonic motor (TWUSM)has potential applications in min-iature robotics.However,its electrical drive circuit presents unique challenges,particularly in producing a high frequency (about 40kHz),high voltage (400V peak-to-peak)signal input to a low impedance capacitive motor,while achieving high efficiency.A novel driving circuit is proposed to provide two-phase balance voltage for a TWUSM.This paper describes the design of TWUSM drive circuit,intended for simultaneously employs both the driving frequency and phase modulation control scheme.The oper-ating principles and a detailed analysis of the proposed driving circuit,consisting of voltage-controlled oscillator (VCO),voltage-controlled phase-shifter circuit and power amplifier circuit,are introduced.To drive the USM effectively a two-phase power amplifier converter using non-resonant technique was designed to provide a balanced two-phase voltage source,and the two-phase output driving voltages could be maintained at the same peak voltage value at the driving frequency under varying phase-mod-ulation processes.Detailed experimental results are provided to demonstrate the effectiveness of the pro-posed driving circuit.Crown Copyright Ó2008Published by Elsevier Ltd.All rights reserved.1.IntroductionThe ultrasonic motor (USM)has many excellent performance features,including high-retention torque,high torque at low speed,silence,compactness in size,and no electromagnetic inter-ference.The USM has been used in a number of industrial,medical,space,robotic,and automotive applications.The driving principles of the USM are high-frequency mechani-cal vibrations and frictional force and its mathematical model is thus difficult to derive.As a result,a lumped motor model of the USM is presently unavailable [1].Moreover,the control character-istics of the USM are complicated and highly nonlinear,as motor parameters are time-varying,owing to increases in temperature and changes in motor-drive operating conditions,such as driving frequency,source voltage and load.Basically,the speed of the TWUSM can be manipulated by con-trolling the frequency,phase difference and the voltage amplitude of the two sinusoidal voltage waveforms which input to the TWUSM.Many researchers have opted for the frequency of the sinusoidal voltage waveforms as the control variable [2–5].It can easily be controlled digitally and spans the entire allowable speed range of the TWUSM.Most TWUSMs contain a two-phase half-bridge series-resonant inverter with an approximated unityswitching frequency (f s )to resonant frequency (f o )ratio.According to the description in the previous paragraph,the quality factors of the two phases are different and time varying.Moreover,when the frequency ratio (f s /f o )of a series-resonant inverter approaches unity,the voltage gain varies severely with the variation of the quality factor [6].Thus,the two-phase sinusoid output voltages are unbalanced under the same switching frequency.Conse-quently,good dynamic performance of the USM is difficult to ob-tain due to the variation in the unbalanced peak values of the two-phase voltages.By contrast,a voltage amplitude control strat-egy using additional boost choppers was employed in [7].Each chopper–inverter driving circuit is composed of one boost chopper cascading with one half-bridge series-resonant parasitic load impedance inverter.Since the two phase constructions of the USM are coupled mechanically and the reaction from the electrical to the mechanical part is unbalanced for both phases,the equiva-lent two-phase loads of the rotor are unbalanced and varied for dif-ferent rotating directions,rotor speeds,load torque,applied voltages and static pressure force between stator and rotor.In addition,the internal two-phase blocking capacitors of the USM are unbalanced and will vary in value under different rotational directions.As a result,it is difficult maintain the two-phase sinu-soid output voltages at the same constant peak value at the same switching frequency.However,a driving circuit proposed by Lin and Kuo [8]operates within working limits where the inverter voltage gain is greatly affected by the variation of the quality0196-8904/$-see front matter Crown Copyright Ó2008Published by Elsevier Ltd.All rights reserved.doi:10.1016/j.enconman.2008.03.023*Corresponding author.E-mail address:tchichen@.tw (T.-C.Chen).Energy Conversion and Management 49(2008)2767–2775Contents lists available at ScienceDirectEnergy Conversion and Managementj ou r na l h om e pa ge :w w w.e lse vi e r.c om /lo c at e /en c on manfactor.Moreover,to resolve the difficulty of the amplitude varia-tion in the output voltages of the parallel-resonant inverter,an ex-tra energy feedback circuit is added to reduce the quality factors in the parallel-resonant circuit.However,the energy feedback circuit increases the complexity of the driving circuit.In addition to the use of a boost converter,a voltage amplitude control strategy may also be implemented using pulse-width mod-ulation(PWM).In[9],the voltage amplitude was adjusted by the forward and backward PWM method for position control of the TWUM.In[10],the voltage amplitude was adjusted by the ON–OFF PWM method for speed control.Both methods essentially adopted the same principle in which the modulation was used to control the ratio of the number of ultrasonic cycles within the for-ward-direction or on-time duration to the total number of ultra-sonic cycles,including the backward-direction or off-time duration.Such control methods cause intermittent operation of the TWUM,leading to the creation of severe audible noise.In order to suppress this audible noise,the PWM should be applied to each ultrasonic cycle[11].Given these limitations,a specific drive circuit control tech-nique is required.Hence,it is desirable to develop a novel drive system that solves these issues while supplying the necessary power with high efficiency.Compared to work on drive circuit design for TWUSM based on the phase difference between the two-phase voltages,less research has been done in other areas of drive circuit design for TWUSM. Only the phase difference control strategy offers the advantage of bidirectional rotation,while the other two parameters of the con-trol scheme,frequency and voltage amplitude,need the assistance of phase-shift change between p/2toÀp/2.In the design of modern drive circuits with adjustable phase dif-ferences,a low-cost and simple phase shifter circuit providing two-phase signals of two-phase voltage source is a critical design issue. The motivation of this study is to design a novel driving scheme that simultaneously employs both the driving frequency and phase difference as dual-mode control variables to handle system nonlin-earities and parameter variations.In order to reduce the system hardware size and cost,the proposed phase shifter circuit is imple-mented by using a voltage-controlled resistance(VCR)and all-pass filter circuit that can provide piecewise-linear phase control over the entire speed range.In the conventional series and parallel resonant converter archi-tecture,two inductances must be inserted in parallel or series with the load for each phase,respectively,in order to become resonant with the inherent two-phase parasitic capacitances of the USM. Moreover,the motor parameters of the USM are dependent on the operating temperature,the running time,and the load.In addi-tion,the equivalent two-phase loads of the rotor are also unbal-anced and the equivalent resistor values vary for different operating conditions.Therefore the quality factors of the resonant inverters in two-phase are unequal and time-varying,resulting in the consumption of time to determine suitable RLC tank compo-nents.In contrast with conventional series and parallel resonant converters with two reactive components,the power amplifier circuit in this study is implemented to build high-frequency two-phase high drive voltages for USM(e.g.400V peak to peak) and is not in need of additional reactive components or a compli-cated energy feedback circuit.Although the quality factors of the two RLC tanks vary at different rotating speeds and are not equal, the output driving voltage of the proposed power amplifier circuit in two-phase can be maintained at the same peak voltage value when the driving frequency is operated close to the resonant frequency.In this paper,the design of a novel phase shifter circuit for applying TWUSM driving is presented.For a USM prototype,the operating principles and characteristics at the operating conditions will be also briefly described.Next,the novel driving circuit for the TWUSM,which contains VCO,VCR,voltage-controlled phase shif-ter,and power amplifier driving circuit,is introduced.The results of experiments investigating the effectiveness of the proposed dri-ver are given in Section4.Finally,a discussion and conclusions are provided in Section5.2.Operating principle and characteristicIn the operation of the TWUSM,a two-stage energy conversion is formed.Thefirst stage consists of the electro-mechanical energy conversion where the electrical energy is converted into mechani-cal energy.This is achieved by excitation of the piezoelectric cera-mic by ultrasonic range frequency.The second stage comprises mechanical energy conversion where the mechanical vibrations are converted to linear or rotary motion by the friction force gen-erated in the stator–rotor interface.Fig.1illustrates the operating principles of the TWUSM.The stator,designed with comb-tooth surface,is attached above the sectors of piezoelectric elements. The piezoelectric elements are divided into sectors instead of form-ing a complete ring so that they can be applied with different voltages.The rotor is pressed against the stator by means of a pressure spring disc.It should be noted that the spring as shown is for illus-tration only,since in reality it is not a normal spring,but a pressure disc.The operating principle of the TWUSM is based on the mechanical vibrations of the piezoelectric elements.As a result of voltages applied to them,they produce a traveling wave in the sta-tor.The surface interaction between the stator and the rotor cre-ates a driving torque in the rotor.As shown in Fig.1, piezoelectric elements are positioned at an appropriate distance from one another.One is produces a mechanical vibration by being fed by the phase-A voltage source V m sin x t,while the other is fed by the phase-B voltage source V m sin(x t+U),generating another vibration,where V m is the amplitude,x=2p f is the angular version of frequency f,and U is the phase difference of the two driving volt-age sources.Each voltage source generates a mode of vibration throughout the stator,and the superposition of them forms a trav-eling wave that propagates along the stator.Depending on which phase of the voltage leads the other,the traveling wave will travel in either a right or left direction.Elliptical motion can be observed at the wave peak of the surface of the stator.Such motion produces a tangential force at the contact surface between the stator and the rotor.With a spring disc to keep the rotor in pressure contact with the stator,the rotor can be driven to travel in the opposite direc-tion from the traveling wave by this tangential force at the contactsurface.Fig.1.TWUSM operating principle[1].2768T.-C.Chen et al./Energy Conversion and Management49(2008)2767–2775The speed of the USM is controlled by:Frequency of two-phase voltages.Amplitude of two-phase voltages.Phase difference between two-phase voltages.3.Drive circuit designFig.2shows actual configuration view of a typical USR-60circu-lar traveling wave type motor(from Shinsei of Japan),in which the specification is a40kHz,0.32Nm,3W,120rev/min type motor. The operation of a mode conversion USM is based on the torque generated by piezoelectric ultrasonic vibrations.An optimal supply voltage for the USM is a sinusoidal voltage with frequency near the mechanical resonance frequency of the stator–rotor assembly. Since this USM presents a large capacitive load and requires a high operating frequency(40kHz),its equivalent impedance could be extremely low.This USM also requires a high drive voltage (400V peak-to-peak),which leads to a large drive current.The goals for drive circuit design are to satisfy these require-ments,as well as achieve high power efficiency and reduce the sys-tem hardware size and cost.In the design of modern drive circuit with adjustable phase difference,the key technology is a low-cost and simple phase shifter circuit,provided two-phase signals from a two-phase voltage source.The purpose of this study is to design a novel driving scheme that simultaneously employs both the driv-ing frequency and phase difference as the dual-mode control vari-ables to handle system nonlinearities and parameter variations. The block diagram of the driving circuit is shown in Fig.3.This cir-cuit is composed of voltage-controlled oscillator(VCO),voltage-controlled phase shifter,power amplifier,and transformer.The design procedures of the proposed drive system are described in detail below.3.1.Voltage-controlled oscillatorThe ICL8038waveform generator is a monolithic integrated cir-cuit capable of producing high accuracy sine,square,triangular, sawtooth,and pulse waveforms with a minimum of external com-ponents[12].The frequency(or repetition rate)can be selected externally from0.001Hz to more than300kHz using either resis-tors or capacitors,and frequency modulation and sweeping can be accomplished with an external frequency-modulated voltage(V f). The frequency of the waveform generator is a direct function of the DC voltage at Terminal8,shown in Fig.4.By altering this volt-age,frequency modulation is performed by means of a voltage-controlled oscillator(VCO).To clarify the relation between the frequency-modulated voltage and the magnitude of the single fre-quency,experimental measurements were made at different volt-age values in Fig.5.Fig.5shows that this characteristic is quite linear.In this study,motor speed is controlled at40–44kHz,which may be considered the linear frequency range.3.2.Voltage-controlled phase shifterFig.6shows afirst-order all-passfilter with a junctionfield-effect transistor(JFET)used as a variable resistor to control the pole and zero time constants in thefilter transfer function.Let VCR R eq be the resistance of the JFET.If we assume that this is a linear resis-tor,the transfer function isTðsÞ¼V oi¼s sÀ1ð1Þwhere the time constant s is given by s=R eq C.By varying the gate-source voltage of JFET(V GS),i.e.the phase-modulated voltage(V p)in Fig.3,the resistance of the JFET can be varied,which in turn changes the time constant s.For s=j x,the phase difference of the transfer function is therefore\Tðj xÞ¼À2tanÀ1x R eq Cð2ÞFig.2.The photograph of experimentalsetup.The magnitude of the transfer function (j T (j x )j )is 1for all fre-quency x .The phase displacement not only depends on the oper-ating frequency of the TWUSM but is also affected by the timeconstant (s ).At different frequencies,between 41and 44kHz,the voltage signal (V i )applied to the USM,the VCR (R eq )drifting through the control voltage (V GS ),and the relationship between them were measured (Table 1).At a specific resonant frequency (f o =41kHz),the goals for phase shifter circuit designed to adjust the phase differential from Àp /2to Àp rad.Fig.6shows a general all-pass filter circuit.The circuit is composed of a resistor,a capac-itor,and an operational amplifier.The frequency of the input signalfor the circuit has to be near the resonant frequency of the TWUSM.We inset the VCR instead of the resistor,and adjusted the proper-ties of the circuit components (R =10k X ,C =0.01l F).As a result,when the operating frequency equal the resonant frequency (f o )and the control voltage minimizes as zero (V GS =0),the phase dis-placement reaches Àp /2rad,i.e.x R eq C =1.Conversely,if the R eq is increased in small increments,the phase difference gradually diminishes.3.3.Voltage-controlled resistanceVoltage-controlled filter,voltage-controlled oscillators,and voltage-to-time period/frequency converters have been applied in many instrumentation and measurement situations.A simple way to realize such circuits is to start from known circuits and then replace resistors by voltage-controlled resistances (VCR).Schemes to construct such VCR using FET’s are known in literature [13].Fig.4.A voltage-controlled oscillatorcircuit.Fig. 5.The measured relation between controlled voltage and output single frequency.Table 1Measurement results of V GS versus R eq V GS (V)0À0.2À0.4À0.6À0.8À1.0R eq (X )357.1416.7471.7531.9617.3746.3V GS (V)À1.2À1.4À1.6À1.8À2.0À2.2R eq (X )943.4128219233846291661Fig.8.FET output characteristics (K30A).2770T.-C.Chen et al./Energy Conversion and Management 49(2008)2767–2775The VCR configuration is shown in Fig.7.A routine analysis of the circuit shows that when the FET is confined to operate in a non-saturated region under the same constraints as in [13,14],the output characteristic of the FET may be represented by a qua-dratic function given by I DS ¼I DSS V p½2ðV GS ÀV p ÞV DS ÀV 2DSð3Þwhere I DSS and V p are saturation current and pinch-off voltage,respectively.The implementation of the voltage-tunable resistance can be simplified by neglecting the V 2DS term of Eq.(3),in which case R eq would be R eq¼V DS DS %V 2pDSS GS p ;providedV DS <j 0:5jð4ÞA typical set of characteristics obtained experimentally for an n-channel JFET (K30A)is shown in Fig.8.The range of values includes those prescribed in [14]as well as larger values,to show the nonlinear nature of these curves.Clearly if thisfield-effectFig.9.Phase displacement against controlvoltage.Fig.10.Measured results of the divergent index coefficient under difference ope-rating control voltage.Fig.12.Generated signals of phase-shifted circuit.(a)Phase difference set at p /2rad (b)p /3(c)p /6(d)0(e)Àp /6(f)Àp /3(g)Àp /2.Fig.13.Measured results of the phase shifter circuit under difference operating driving frequency.T.-C.Chen et al./Energy Conversion and Management 49(2008)2767–27752771transistor(FET)is to be used as a bidirectional linear resistor,j V DS j should be kept low,at least less than500mV,particularly for prac-tical circuit applications.For the relationship between the phase displacement angle(U) and the control voltage(V GS),the analysis of the phase shifter cir-cuit should yield the following results by observing the phase dis-placement versus control voltage curve in Fig.9x R eq C%tanðaV GSþbÞð5ÞUsing Eq.(5)to simplify Eq.(2),the following relationship results:\T¼À2ðaVGSþbÞð6Þwhere the constants a and b are calculated to define as a=À0.3865, b=p/4,and were used in the verifications below.Note that,as ex-pected,even nonlinearities do not appear in Eq.(6),as they are can-celed out.In the following,we test the divergence between the theoretical formula and experimental data and also define the divergent index coefficient D(the ratio of the phase value according to Eq.(6)di-vided by the actual phase displacement relating to Eq.(2)of exper-imental data)asD¼À2ðaV GSþbÞÀ2tanÀ1ðx R eq CÞð7ÞTo illustrate the difference between(2)and(6),actual and esti-mated UÀV GS curves using both schemes are presented in Fig.9. The measured index coefficient(D)of the divergence as the input control voltage swing during different operating values is shown in Fig.10.As thisfigure shows,a reasonably good correspondence is observed between the two sets of data,confirming the validity of the above supposition property regarding Eq.(6).A phase shifter circuit was designed to provide two-phase sig-nals of two-phase driving voltage sources with a phase difference ranging from p/2toÀp/2.To design a low-cost,simple phase shifter circuit for a TWUSM,we constructed a phase-regulating driving circuit for the USM by utilizing the VCR and all-passfilter circuit.The proposed phase shifter circuit,shown in Fig.11, has dual complementary channels,in which the sinusoid output signals have angles complementary to each other (\A+\B=90°).The driving voltage signals with the phase difference from the phase shifter circuit for the resonance frequency of TWUSMsetFig.14.A Push–pull class-B amplifier with Darlingtonpairs.Fig.15.Rotational speed versus driving frequency under freeloading.Fig.16.Two-phase output voltages of phase-modulation driving circuit for drivingfrequency set at41kHz:the phase regulated as equal value.2772T.-C.Chen et al./Energy Conversion and Management49(2008)2767–2775at 40kHz are shown in Fig.12.Even if the phase in the phase shifter circuit was slightly affected by the operating driving frequency,the output signals in phase A and B can still maintain symmetrical amplitude and the range of phase difference reaches ±p /2rad.By observing the characteristics of the measured phase difference angle versus the phase-modulated voltage (V p ),shown in Fig.13,we found that the relationship between the phase difference angle (U )and phase-modulated voltage (V p )is highly linear over a wide operating range under different driving frequencies.3.4.Power amplifiers and transformerA practical circuit using ClassB elements is a complementary pair or push–pull arrangement.Here,complementary devices are used to each amplify the opposite halves of the input signal,which is then recombined at the output.This arrangement gives excellent efficiency,but can suffer from the drawback of a small glitch at the joins between the two halves of the signal,a problem known as crossover distortion.A solution to this is to bias the devices just on,rather than off altogether,when they are not in use.One way to greatly boost the current gain (A I )of a Class B push–pull ampli-fier is to use Darlington pairs instead of single transistors,shown in Fig.14.Since this USM presents a large capacitive load and requires a high operating frequency,its equivalent impedance could be extre-mely low.This USM also requires a high drive voltage,which leads to a large drive current.Hence,a ferrite-core transformer which features high efficiency,small size,and light weight,was chosen to isolate and boost the high frequency AC voltage.The non-reso-nant power amplifier circuits are designed in order to provide two-phase,phase A and B,sinusoid output voltages V A and V B with the same amplitude under the variable frequency and phase con-trol.According to experiment test in Section 4,the amplitude of the output voltage will not be affected by the variation of the qual-ity when the driving frequency is operated closely to the resonant frequency of the TWUSM.The phase B power amplifier circuit is designed using the same method as for phase A.4.Experimental resultsA prototype of power driver for a TWUSM was built and tested.Based on the circuit design of TWUSM driver discussed above,mo-tor performance was measured by experimental results.There are three basic input signals for the TWUSM:frequency,independence amplitude,and phase.It is important to confirm the driving char-acteristics for eachparameter.Fig.17.Experimental results of phase-modulation driving circuit for driving frequency set at 41kHz,10l s/div.(a)Two-phase output voltages with phase difference p /6for CW rotation.(b)Two-phase output voltages with phase difference p /6for CCWrotation.Fig.18.Experimental results of phase-modulation driving circuit for driving frequency set at 41kHz,10l s/div.(a)Two-phase output voltages with phase difference p /3for CW rotation.(b)Two-phase output voltages with phase difference p /3for CCW rotation.T.-C.Chen et al./Energy Conversion and Management 49(2008)2767–27752773First,we measured the rotational speed in relation to the driv-ing frequency in Fig.15.The mechanical resonant frequency of the USM (USR-60)ranges from 39to 40kHz in the ultrasonic fre-quency range.The switching frequency of the voltage-controlled oscillator,which is designed to vary between 40.5and 44kHz,should be higher than the resonant frequency of the mechanical vibration.The highest rotational speeds around the phase differ-ence p /2were roughly 229and 221rpm in the direction of CW and CCW,respectively.The frequency,at around 40.5kHz,is nearly the same as the natural resonance frequency of TWUSM as de-scribed above.This characteristic is the same as that of a conven-tional single-frequency-mode control ultrasonic motor.The vibration velocity becomes high near the resonant frequency of the stator,which means the rotational velocity of the rotor reaches its maximum value.Subsequently,we tested the rotational speed in relation to the phase difference.The phase shifter circuit worked as mentioned above.The control input to the drive circuit (V p )is calculated by the control algorithm.According to the control input,the phase dif-ference (U )is regulated by means of the designed phase shifter cir-cuit.The phase shifter circuit is designed for the two-phase power amplifier to provide two-phase output voltages V A and V B with var-iable phase difference,where the rotational direction (CW or CCW)can be controlled by allowing either V A or V B to lead.In order to as-sess the performance and stability of the proposed phase-mode driver for TWUSM,the phase differences of two-phase AC outputvoltage has been regulated from 0to ±p /2rad,shown in Figs.16–19,respectively.The two-phase sinusoid output V A and V B can thus be maintained at the same constant peak value at the switching frequency under varying phase-modulation processes.The driving phase difference of the designed phase-shifter circuit is the major control variable,and balanced two-phase sinusoid output voltages with the same amplitudes and variable-phase control results in satisfactory control performance of the TWUSM servo drive.Fig.20shows the experimental results of the Speed versus phase difference curves under variable operating driving frequencies.Experimental results confirm that the rotor could be rotated using the design driving circuit.By comparison,the phase-mode driving can offer a much wider controllable range,which verifies that the proposed driver circuit can successfully adapt the change of com-mand signals.In addition to these advantages,only the phase shift parameter can control the rotational direction of a rotor,which the phase-shift varies between p /2and Àp /2.5.ConclusionsUSMs are potentially interesting for a number of industry appli-cations,such as miniature robotics.Their electrical drive circuits present unique challenges,particularly in producing signals of several hundred volts and tens of kilohertz with variable phase dif-ferences,inputted to a low impedance capacitive motor,whileFig.20.Rotational speed versus phase difference under difference operating drivingfrequency.Fig.19.Experimental results of phase-modulation driving circuit for driving frequency set at 41kHz,10l s/div.(a)Two-phase output voltages with phase difference p /2for CW rotation.(b)Two-phase output voltages with phase difference p /2for CCW rotation.2774T.-C.Chen et al./Energy Conversion and Management 49(2008)2767–2775。
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普通钻床改造为多轴钻床
目前，我国中、小型企业的产品质量和生产效率都需要有一个新的提高, 但是加工手段却远远不能满足需要, 许多中小型企业都结合自己的实际对设备的技术状态进行改进，通过强化自身, 以求自我发展普通钻床为单轴机床，但安装上多轴箱就会成为多轴的钻床，改造成多轴钻床后，能大大地缩短加工时间，提高生产效率。
多轴加工应用：据统计，一般在车间中普通机床的平均切削时间很少超过全部工作时间的15%。
其余时间是看图、装卸工件、调换刀具、操作机床、测量以及清除铁屑等等。
使用
数控机床虽然能提高85%，但购置费用大。
某些情况下，即使生产率高，但加工相同的零件，其成本不一定比普通机床低。
故必须更多地缩短加工时间。
不同的加工方法有不同的特点，就钻削加工而言，多轴加工是一种通过少量投资来提高生产率的有效措施。
多轴加工优势：虽然不可调式多轴头在自动线中早有应用，但只局限于大批量生产。
即使采用可调式多轴头扩大了使用范围，仍然远不能满足批量小、孔型复杂的要求。
尤其随着工业的发展，大型复杂的多轴加工更是引人注目。
例如原子能发电站中大型冷凝器水冷壁管板有15000个“ 20孔，若以摇臂钻床加工，单单钻孔与锪沉头孔就要842.5小时，另外还要
划线工时151.1 小时。
但若以数控八轴落地钻床加工，钻锪孔只要171.6 小时，划线也简单，只要1.9 小时。
因此，利用数控控制的二个坐标轴，使刀具正确地对准加工位置，结合多轴加工不但可以扩大加工范围，而且在提高精度的基础上还能大大地提高工效，迅速地制造出原来不易加工的零件。
有人分析大型高速柴油机30 种箱形与杆形零件的2000 多个钻孔操作中，有40%可以在自动更换主轴箱机床中用二轴、三轴或四轴多轴头加工，平均可减少20%的加工时间。
1975年法国巴黎机床展览会也反映了多轴加工的使用愈来愈多这一趋势。
多轴加工的设备：多轴加工是在一次进给中同时加工许多孔或同时在许多相同或不同工件上各加工一个
孔。
这不仅缩短切削时间，提高精度，减少装夹或定位时间，并且在数控机
床中不必计算坐标，减少字块数而简化编程。
它可以采用以下一些设备进行加工：立钻或摇臂钻上装多轴头、多轴钻床、多轴组合机床心及自动更换主轴箱机床。
甚至可以通过二个能
自动调节轴距的主轴或多轴箱，结合数控工作台纵横二个方向的运动，加工各种圆形或椭圆
形孔组的一个或几个工序。
现在就这方面的现状作一简介。
多轴头：从传动方式来说主要有齿轮传动与万向联轴节传动二种。
这是大家所熟悉的。
前者效率较高，结构简单，后者易于调整轴距。
从结构来说有不可调式与可调式二种。
前者轴距不能改变，多采用齿轮传动，仅适用于大批量生产。
为了扩大其赞许适应性，发展了可调式多轴头，在一定范围内可调整轴距。
它主要装在有万向. 二种。
（1）万向轴式也有二种: 具有对准装置的主轴。
主轴装在可调支架中，而可调支架能在壳体的T 形槽中移动，并能在对准的位置以螺栓固定。
（2）具有公差的圆柱形主轴套。
主轴套固定在与式件孔型相同的模板中。
前一种适用于批量小且孔组是规则分布的工件（如孔组分布在不同直径的圆周上）后一种适用于批量较大式中小批量的轮番生产中，刚性较好，孔距精度亦高，但不同孔型需要不同的模板。
多轴头可以装在立钻式摇臂钻床上，按钻床本身所具有的各种功能进行工作。
这种多轴加工方法，由于钻孔效率、加工范围及精度的关系，使用范围有限。
多轴箱：也象多轴头那样作为标准部件生产。
美国Secto 公司标准齿轮箱、多轴箱等设计
的不可调式多轴箱。
有32种规格，加工面积从300 X 300毫米到600 X1050毫米，工作轴达60根，动力达22.5千瓦。
Romai工厂生产的可调多轴箱调整方便，只要先把齿轮调整到接近孔型的位置，然后把与它联接的可调轴移动到正确的位置。
因此，这种结构只要改变模板，就能在一定范围内容易地改变孔型，并且可以达到比普通多轴箱更小的孔距。
根据成组加工原理使用多轴箱或多轴头的组合机床很适用于大中批量生产。
为了在加工中获得良好的效果，必需考虑以下数点：（1）工件装夹简单，有足够的冷却液冲走铁屑。
（2）夹具刚性好，
加工时不形变，分度定位正确。
（3）使用二组刀具的可能性，以便一组使用，另一组刃磨与调整，从而缩短换刀停机时间。
（4）使用优质刀具，监视刀具是否变钝，钻头要机磨。
（5）尺寸超差时能立即发现。
多轴钻床：这是一种能满足多轴加工要求的钻床。
诸如导向、功率、进给、转速与加工范围
等。
巴黎展览会中展出的多轴钻床多具液压进给。
其整个工作循坏如快进、工进与清除铁屑等都是自动进行。
值得注意的是，多数具有单独的变速机构，这样可以适应某一组孔中不同孔径的加工需要。
（1）自动更换主轴机床
自动更换主轴机床顶部是回转式主轴箱库，挂有多个不可调主轴箱。
纵横配线盘予先编好工作程序，使相应的主轴箱进入加工工位，定位紧并与动力联接，然后装有工件的工作台转动到主轴箱下面，向上移动进行加工。
当变更加工对象时，只要调换悬挂的主轴箱，就能适应不同孔型与不同工序的需要。
（2）多轴转塔机床
转塔上装置多个不可调或万向联轴节主轴箱，转塔能自动转位，并对夹紧在回转工作台的工件作进给运动。
通过工作台回转，可以加工工件的多个面。
因为转塔不宜过大，故它的工位数一般不超过4—6 个。
且主轴箱也不宜过大。
当加工对象的工序较多、尺寸较大时，就不如自动更换主轴箱机床合适，但它的结构简单。
（3）自动更换主轴箱组合机床
它由自动线或组合机床中的标准部件组成。
不可调多轴箱与动力箱按置在水平底座上，主轴箱库转动时整个装置紧固在进给系统的溜板上。
主轴箱库转动与进给动作都按标准子程序工作。
换主轴箱时间为几秒钟。
工件夹紧于液压分度回转工作台，以便加工工件的各个面。
好果回转工作台配以卸料装置，就能合流水生产自动化。
在可变生产系统中采用这种装置，并配以相应的控制器可以获得完整的加工系统。
(4) 数控八轴落地钻床
大型冷凝器的水冷壁管板的孔多达15000个，它与支撑板联接在一起加工。
孔径为20 毫米，
孔深180 毫米。
采用具有内冷却管道的麻花钻，5－7 巴压力的冷却液可直接进入切削区，有利于排屑。
钻尖磨成90°供自动定心。
它比普通麻花钻耐用，且进给量大。
为了缩短加工时间，以8 轴数控落地加工。
多轴加工趋势：多轴加工生产效率高，投资少，生产准备周期短，产品改型时设备损失少。
而且随着我国数控技术的发展，多轴加工的范围一定会愈来愈广，加工效率也会不断提高。
生产任务：在一批铸铁连接件上有同一个面上有多个孔加工。
在普通立式钻床上进行孔加工，通常是一个孔一个孔的钻削，生产效率低，用非标设备，即组合机床加工，生产效率高，但设备投资大。
但把一批普通立式普通单轴钻床改造为立式多轴钻床，改造后的多轴钻床，可以同时完成多个孔的钻、扩、铰、等工序。