虚拟制造在齿轮生产中的应用外文翻译、中英文翻译、机械类外文文献翻译
毕业设计外文翻译齿轮
Gears are vital factors in machinery. One of the first mechanism invented using gears was the clocks. In fact, a clock is little more than a train of study and research have been made on gears in recent years because of their wide use under exacting conditions. They have to transmit heavier loads and run at higher speeds than ever before. The engineers and the machinists all consider gearing the prime elementin nearly all classes of machinery.齿轮在机械中占有极为重要的作用。
第一个利用齿轮做成的机械装置确实是钟表，事实上，它只只是是用了一系列的齿轮。
关于它能够在严格的条件下的普遍利用，在齿轮上做了大量的学习和研究。
相较过去，它们此刻必需在更高的速度下传递更重的负荷。
工程师和机械操纵工人都以为齿轮在几乎所有的机械的零件中占有首要的因素。
1. Spur gearsSpur gears are used to transmit power and rotary motion between parallel shafts. The teeth are cut parallel to the axis of the shaft on which the gears are mounted. The smaller of two gears in mesh is called the pinion and the larger is customarily Designated as the gear. In most applications, the pinion is the driving element whereas the gear is the driven element.1.直齿圆柱齿轮直齿圆柱齿轮用于平行轴之间传递力和回转运动，轮齿被切制成与安装齿轮的轴之轴线相平行。
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。
机械零件齿轮中英文对照外文翻译文献
(文档含英文原文和中文翻译)中英文资料对照外文翻译Machine Parts (I)GearsGears are direct contact bodies, operating in pairs, that transmit motion and force from one rotating shaft to another or from a shaft to a slide (rack), by means of successively engaging projections called teeth.Tooth profiles. The contacting surfaces of gear teeth must be aligned in such a way that the drive is positive; i.e., the load transmitted must not depend on frictional contact. As shown in the treatment of direct contact bodies, this requires that thecommon normal to the surfaces not to pass through the pivotal axis of either the driver or the follower.As it is known as direct contact bodies, cycloidal and involute profiles profiles provide both a positive drive and a uniform velocity ratio;i.e., conjugate action.Basic relations. The smaller of a gear pair is called the pinion and the larger is the gear. When the pinion is on the driving shaft the pair is called the pinion and the larger is the gear. When the pinion is on the driving shaft the pair acts as a speed reducer; When the gear drives, the pair is a speed incrreaser. Gears are more frequently used to reduce speed than to increase it.If a gear having N teeth rotates at n revolutions per minute, the product N*n has the dimension “teeth per minute”. This product must be the same for both members of a mating pair if each tooth acquires a partner from the mating gear as it passes through the region of tooth engagement.For conjugate gears of all types, the gear ratio and the speed ratio are both given by the ratio of the number of teeth on the gear to the number of teeth on the pinion. If a gear has 100 teeth and a mating pinion has 20, the ratio is 100/20=5. Thus the pinion rotates five times as fast as the gear, regardless of the gear. Their point of tangency is called the pitch point, and since it lies on the line of centers, it is the only point at which the profiles have pure roling contact. Gears on nonparallel, non-intersecting shafts also have pitch circles, but the rolling-pitch –circle concept is not valid.Gear types are determined largely by the disposition of the shafts; in addition, certain types are better suited than others for large speed changes. This means that if a specific disposition of the shafts is required, the type of gear will more or less be fixed. On the other hand, if a required speed change demands a certain type, the shaft positions will also be fixed.Spur gears and helical gears. A gear having tooth elements that are straight and parallel to its axis is known as a spur gear. A spur pair can be used to connect parallel shafts only.If an involute spur pinion were made of rubber and twisted uniformly so that the ends rotated about the axis relative to one another, the elements of the teeth, initially straight and parallel to the axis, would become helices. The pinion then in effect would become a helical gear.Worm and bevel gears. In order to achieve line contact and improve the load carrying capacity of the crossed axis helical gears, the gear can be made to curvepartially around the pinion, in somewhat the same way that a nut envelops a screw. The result would be a cylindrical worm and gear. Worms are also made in the shape of an hourglass, instead of cylindrical, so that they partially envelop the gear. This results in a further increase in load-carrying capacity.Worm gears provide the simplest means of obtaining large ratios in a single pair. They are usually less efficient than parallel-shaft gears, however, because of an additional sliding movement along the teeth.V-beltThe rayon and rubber V-belt are widely used for power transmission. Such belts are made in two series: the standard V-belt and the high capacity V-belt. The belts can be used with short center distances and are made endless so that difficulty with splicing devices is avoided.First, cost is low, and power output may be increased by operating several belts side by side. All belts in the drive should stretch at the same rate in order to keep the load equally divided among them. When one of the belts breaks, the group must usually be replaced. The drive may be inclined at any angle with tight side either top or bottom. Since belts can operate on relatively small pulleys, large reductions of speed in a single drive are possible.Second，the included angle for the belt groove is usually from 34°to 38°.The wedging action of the belt in the groove gives a large increase in the tractive force developed by the belt.Third，pulley may be made of cast iron, sheet steel, or die-cast metal. Sufficient clearance must be provided at the bottom of the groove to prevent the belt from bottoming as it becomes narrower from wear. Sometimes the larger pulley is not grooved when it is possible to develop the required tractive force by running on the inner surface of the belt. The cost of cutting the grooves is thereby eliminated. Pulleys are on the market that permit an adjustment in the width of the groove. The effective pitch diameter of the pulley is thus varied, and moderate changes in the speed ratio can be secured.Chain DrivesThe first chain-driven or “safety” bicycle appeared in 1874, and chains were used for driving the rear wheels on early automobiles. Today, as the result of modern design and production methods, chain drives that are much superior to their prototypes are available, and these have contributed greatly to thedevelopment of efficient agricultural machinery, well-drilling equipment, and mining and construction machinery. Since about 1930 chain drives have become increasingly popular, especially for power saws, motorcycle, and escalators etc.There are at least six types of power-transmission chains; three of these will be covered in this article, namely the roller chain, the inverted tooth, or silent chain, and the bead chain. The essential elements in a roller-chain drive are a chain with side plates, pins, bushings (sleeves), and rollers, and two or more sprocket wheels with teeth that look like gear teeth. Roller chains are assembled from pin links and roller links. A pin link consists of two side plates connected by two pins inserted into holes in the side plates. The pins fit tightly into the holes, forming what is known as a press fit. A roller link consists of two side plates connected by two press-fitted bushings, on which two hardened steel rollers are free to rotate. When assembled, the pins are a free fit in the bushings and rotate slightly, relative to the bushings when the chain goes on and leaves a sprocket.Standard roller chains are available in single strands or in multiple strands, In the latter type, two or more chains are joined by common pins that keep the rollers in the separate strands in proper alignment. The speed ratio for a single drive should be limited to about 10∶1; the preferred shaft center distance is from 30 to 35 times the distance between the rollers and chain speeds greater than about 2500 feet (800 meters) per minute are not recommended. Where several parallel shafts are to be driven without slip from a single shaft, roller chains are particularly well suited.An inverted tooth, or silent chain is essentially an assemblage of gear racks, each with two teeth, pivotally connected to form a closed chain with the teeth on the inside, and meshing with conjugate teeth on the sprocket wheels. The links are pin-connected flat steel plates usually having straight-sided teeth with an included angle of 60 degrees. As many links are necessary to transmit the power and are connected side by side. Compared with roller-chain drives, silent-chain drives are quieter, operate successfully at higher speeds, and can transmit more load for the same width. Some automobiles have silent-chain camshaft drives.Bead chains provide an inexpensive and versatile means for connecting parallel or nonparallel shafts when the speed and power transmitted are low. The sprocket wheels contain hemispherical or conical recesses into which the beads fit. The chains look like key chains and are available in plain carbon and stainless steel and also in the form of solid plastic beads molded on a cord. Bead chains are used oncomputers, air conditioners, television tuners, and Venetian blinds. The sprockets may be steel, die-cast zinc or aluminum, or molded nylon.Machine Parts (II)FastenerFasteners are devices which permit one part to be joined to a second part and, hence, they are involved in almost all designs.There are three main classifications of fasteners, which are described as follows：(1) Removable. This type permits the parts to be readily disconnected without damaging the fastener. An example is the ordinary nut-and-bolt fastener.(2) Semi permanent. For this type, the parts can be disconnected, but some damage usually occurs to the fastener. One such example is a cotter pin.(3) Permanent. When this type of fastener is used, it is intended that the parts will never be disassembled. Examples are riveted joints and welded joints.The importance of fasteners can be realized when referring to any complex product. In the case of the automobile, there are literally thousands of parts which are fastened together to produce the total product. The failure or loosening of a single fastener could result in a simple nuisance such as a door rattle or in a serious situation such as a wheel coming off. Such possibilities must be taken into account in the selection of the type of fastener for the specific application.Nuts, bolts, and screws are undoubtedly the most common means of joining materials. Since they are so widely used, it is essential that these fasteners attain maximum effectiveness at the lowest possible cost. Bolts are, in reality, carefully engineered products with a practically infinite use over a wide range of services.An ordinary nut loosens when the forces of vibration overcome those of friction. In a nut and lock washer combination, the lock washer supplies an independent locking feature preventing the nut from loosening. The lock washer is useful only when the bolt might loosen because of a relative change between the length of the bolt and the parts assembled by it. This change in the length of the bolt can be caused by a number of factors-creep in the bolt, loss of resilience, difference in thermal expansion between the bolt and the bolted members, or wear. In the above static cases, the expanding lock washer holds the nut under axial load and keeps the assembly tight. When relative changes are caused by vibration forces, the lock washer is not nearly as effective.Rivets are permanent fasteners. They depend on deformation of their structure for their holding action. Rivets are usually stronger than the thread-type fastener and are more economical on a first-cost basis. Rivets are driven either hot or cold,depending upon the mechanical properties of the rivet material. Aluminum rivets, for instance, are cold-driven, since cold working improves the strength of aluminum. Most large rivets are hot-driven, however.ShaftVirtually all machines contain shafts. The most common shape for shafts is circular and the cross section can be either solid or hollow (hollow shafts can result in weight savings).Shafts are mounted in bearings and transmit power through such devices as gears, pulleys, cams and clutches. These devices introduce forces which attempt to bend the shaft; hence, the shaft must be rigid enough to prevent overloading of the supporting bearings. In general, the bending deflection of a shaft should not exceed 0.01 in. per ft. of length between bearing supports.For diameters less than 3 in., the usual shaft material is cold-rolled steel containing about 0.4 percent carbon. Shafts are either cold-rolled or forged in sizes from 3 in. to 5 in. .For sizes above 5 in. , shafts are forged and machined to size. Plastic shafts are widely used for light load applications. One advantage of using plastic is safety in electrical applications, since plastic is a poor conductor of electricity.Another important aspect of shaft design is the method of directly connecting one shaft to another. This is accomplished by devices such as rigid and flexible couplings.BearingA bearing can be defined as a member specifically designed to support moving machine components. The most common bearing application is the support of a rotating shaft that is transmitting power from one location to another. Since there is always relative motion between a bearing and its mating surface, friction is involved. In many instances, such as the design of pulleys, brakes, and clutches, friction is desirable. However, in the case of bearings, the reduction of friction is one of the prime considerations：Friction results in loss of power, the generation of heat, and increased wear of mating surfaces.The concern of a machine designer with ball bearings and roller bearings is fivefold as follows：(1) Life in relation to load; (2) stiffness, i.e. deflections under load;(3) friction; (4) wear; (5) noise. For moderate loads and speeds the correct selection ofa standard bearing on the basis of load rating will usually secure satisfactoryperformance. The deflection of the bearing elements will become important where loads are high, although this is usually of less magnitude than that of the shafts or other components associated with the bearing. Where speeds are high special cooling arrangements become necessary which may increase frictional drag. Wear is primarily associated with the introduction of contaminants, and sealing arrangements must be chosen with regard to the hostility of the environment.Notwithstanding the fact that responsibility for the basic design of ball bearings and roller bearings rests with the bearing manufacturer, the machine designer must form a correct appreciation of the duty to be performed by the bearing and be concerned not only with bearing selection but with the conditions for correct installation.The fit of the bearing races onto the shaft or onto the housings is of critical importance because of their combined effect on the internal clearance of the bearing as well as preserving the desired degree of interference fit. Inadequate interference can induce serious trouble from fretting corrosion. The inner race is frequently located axially by abutting against a shoulder. A radius at this point is essential for the avoidance of stress concentration and ball races are provided with a radius or chamfer to allow space for this.A journal bearing, in its simplest form, is a cylindrical bushing made of a suitable material and containing properly machined inside and outside diameters. The journal is usually the part of a shaft or pin that rotates inside the bearing.Journal bearings operate with sliding contact, to reduce the problems associated with sliding friction in journal bearings, a lubricant is used in conjunction with compatible mating materials. When selecting the lubricant and mating materials, one must take into account bearing pressures, temperatures and also rubbing velocities. The principle function of the lubricant in sliding contact bearings is to prevent physical contact between the rubbing surfaces. Thus the maintenance of an oil film under varying loads, speeds and temperature is the prime consideration in sliding contact bearings.Introduction to Machinery DesignMachinery design is either to formulate an engineering plan for the satisfaction of a specified need or to solve an engineering problem. It involves a range of disciplines in materials, mechanics, heat, flow, control, electronics and production.Machinery design may be simple or enormously complex, easy or difficult, mathematical or nonmathematical, it may involve a trivial problem or one of great importance. Good design is the orderly and interesting arrangement of an idea to provide certain results or effects. A well-designed product is functional, efficient, and dependable. Such a product is less expensive than a similar poorly designed product that does not function properly and must constantly be repaired.People who perform the various functions of machinery design are typically called industrial designers. He or she must first carefully define the problem, using an engineering approach, to ensure that any proposed solution will solve the right problem. It is important that the designer begins by identifying exactly how he or she will recognize a satisfactory alternative, and how to distinguish between two satisfactory alternatives in order to identify the better. So industrial designers must have creative imagination, knowledge of engineering, production techniques, tools, machines, and materials to design a new product for manufacture, or to improve an existing product.In the modern industrialized world, the wealth and living standards of a nation are closely linked with their capabilities to design and manufacture engineering products. It can be claimed that the advancement of machinery design and manufacturing can remarkably promote the overall level of a country’s industrization. Our country is playing a more and more vital role in the global manufacturing industry. To accelerate such an industrializing process, highly skilled design engineers having extensive knowledge and expertises are needed.Machinery ComponentsThe major part of a machine is the mechanical system. And the mechanical system is decomposed into mechanisms, which can be further decomposed into mechanical components. In this sense, the mechanical components are the fundamental elements of machinery. On the whole, mechanical components can be classified as universal and special components. Bolts, gear, and chains are the typical examples of the universal components, which can be used extensively in different machines across various industrial sectors. Turbine blades, crankshaft and aircraftpropeller are the examples of the special components, which are designed for some specific purposes.Mechanical Design ProcessProduct design requires much research and development. Many concepts of an idea must be studied, tried, refined, and then either used or discarded. Although the content of each engineering problem is unique, the designers follow the similar process to solve the problems.Recognition of NeedSometimes, design begins when a designer recognizes a need and decides to do something about it. The need is often not evident at, all; recognition is usually triggered by a particular adverse circumstance or a set of random circumstances, which arise almost simultaneously. Identification of need usually consists of an undefined and vague problem statement.Definition of ProblemDefinition of problem is necessary to fully define and understand the problem, after which it is possible to restate the goal in a more reasonable and realistic way than the original problem statement. Definition of the problem must include all the specifications for the thing that is to be designed. Obvious items in the specifications are the speeds, feeds, temperature limitations, maximum range, expected variation in the variables, and dimensional and weight limitations.SynthesisThe synthesis is one in which as many alternative possible design approaches are sought, usually without regard for their value or quality. This is also sometimes called the ideation and invention step in which the largest possible number of creative solutions is generated. The synthesis activity includes the specification of material, addition of geometric features, and inclusion of greater dimensional detail to the aggregate design.AnalysisAnalysis is a method of determining or describing the nature of something by separating it into its parts. In the process the elements, or nature of the design, are analyzed to determine the fit between the proposed design and the original design goals.EvaluationEvaluation is the final proof of a successful design and usually involves thetesting of a prototype in the laboratory. Here we wish to discover if the design really satisfies the needs.The above description may give an erroneous impression that this process can be accomplished in a linear fashion as listed. On the contrary, iteration is required within the entire process, moving from any step back to any previous step, in all possible combinations, and doing this repeatedly.PresentationCommunicating the design to others is the finial, vital presentation step in the design process. Basically, there are only three means of communication. These are the written, the oral, and the graphical forms. A successful engineer will be technically competent and versatile in all three forms of communication. The competent engineer should not be afraid of the possibility of not succeeding in a presentation. In fact, the greatest gains are obtained by those willing to risk defeat.Contents of Machinery DesignMachinery design is an important technological basic course in mechanical engineering education. Its objective is to provide the concepts, procedures, data, and decision analysis techniques necessary to design machine elements commonly found in mechanical devices and systems; to develop engineering students’ competence of machine design that is the primary concern of machinery manufacturing and the key to manufacture good products.Machinery design covers the following contents：Provides an introduction to the design process, problem formulation, safety factors.Reviews the material properties and static and dynamic loading analysis, including beam, vibration and impact loading.Reviews the fundamentals of stress and defection analysis.Introduces static failure theories and fracture-mechanics analysis for static loads.Introduces fatigue-failure theory with the emphasis on stress-life approaches to high-cycle fatigue design, which is commonly used in the design of rotation machinery.Discusses thoroughly the phenomena of wear mechanisms, surface contact stresses, and surface fatigue.Investigates shaft design using the fatigue-analysis techniques.Discusses fluid-film and rolling-element bearing theory and application.Gives a thorough introduction to the kinematics, design and stress analysis of spur gears, and a simple introduction to helical, bevel, and worm gearing.Discusses spring design including helical compression, extension and torsion springs.Deals with screws and fasteners including power screw and preload fasteners.Introduces the design and specification of disk and drum clutches and brakes.机械零件(I)齿轮齿轮是直接接触，成对工作的实体，在称为齿的凸出物的连续啮合作用下，齿轮能将运动和力从一个旋转轴传递到另一个旋转轴，或从一个轴传递到一个滑块(齿条)。
(完整版)齿轮英语文献
Helical, Worm and Bevel GearsGears are machine elements that transmit motion by means of successively engaging teeth. Gears transmit motion from one rotating shaft to another, or to a rack that translates. Numerous applications exist in which constant angular velocity ratio (or constant torque ratio) must be transmitted between shafts. Based on the variety of gear types available, there is no restriction that the input and the output shafts need be either in-line or parallel. Nonlinear angular velocity ratios are also available by using noncircular gears. In order to maintain a constant angular velocity, the individual tooth profile must obey the fundamental law of gearing: for a pair of gears to transmit a constant angular velocity ratio, the shape of their contacting profiles must be such that the common normal passes through a fixed point on the line of the centers.Any two mating tooth profiles that satisfy the fundamental law of gearing are called conjugate profiles. Although there are many tooth shapes possible in which a mating tooth could be designed to satisfy the fundamental law, only two are in general use: the cycloidal and involute profiles. The involute has important advantages: it is easy to manufacture and the center distance between a pair of involute gears can be varied without changing the velocity ratio. Thus close tolerances between shafts are not required when utilizing the involute profile.There are several standard gear types. For applications with parallel shafts, straight spur gear, parallel helical, or herringbone gears are usually used. In the case of interesting shafts, straight bevel or spiral bevel gears are employed. For nonintersecting and nonparallel shafts, crossed helical, worm, face, skew bevel or hypoid gears would be acceptable choices. For spur gears, the pitch circles of mating gears are tangent to each other. They roll on one another without sliding. The addendum is the height by which a tooth projects beyond the pitch circle (also the radial distance between the pitch circle and the addendum circle). The clearance is the amount by which the dedendum (tooth height below the pitch circle) in a given gear exceeds the addendum of its mating gear. The tooth thickness is the distance across the tooth along the arc of the pitch circle while the tooth space is the distance between adjacent teeth along the arc of the pitch circle. The backlash is the amount by which the width of the tooth space exceeds the thickness of the engaging tooth at the pitchcircle.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 engagement 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.Worm gears are similar to crossed helical gears .The pinlon 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 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 is one in which the gear wraps around or partially encloses the worm. A gearing in 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 gear of a set have the same hand of helix as for crossed helical gears, but the helix angle are usually quiet different. The helix angle on the worm is generally quiet large, and that on the gear very small. Because of this, it is usual tospecify 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 90-deg.shaft angle.When gears are to be used to transmit motion between intersecting shafts, some form of bevel gear is required. Although bevel gears are usually made for a shaft angle of 90 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 the teeth. Another difficulty, which occurs in predicting the stress in bevel-gear teeth, is the fact that 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 spur gears, however, they become noisy at higher values of the pitch-line velocity. In these cases it is often good design practice to go to the spiral bevel gear, which is the bevel counterpart of the helical 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.斜齿轮，蜗杆和圆锥齿轮齿轮是通过轮齿连续啮合的方式传递运动的机器零件。
工业智能制造英文文献原文及译文
工业智能制造英文文献原文及译文原文：1. Title: Industrial Intelligent Manufacturing: Integration and Transformation2. Abstract: With the rapid development of information technology, the manufacturing industry is undergoing a profound transformation, and intelligent manufacturing is bing a new trend. This paper reviews the concept and key technologies of industrial intelligent manufacturing, discusses the integration of advanced manufacturing technologies, and explores the transformation of traditional manufacturing to intelligent manufacturing.3. Introduction: Industrial intelligent manufacturing, also known as smart manufacturing, refers to the use of advanced technologies such as Internet of Things (IoT), artificial intelligence, big data, and cloudputing to improve the efficiency and productivity of manufacturing processes. It involves the integration of cyber-physical systems, Internet technologies, and advanced manufacturing technologies to create a moreflexible, efficient, and personalized production environment.4. Key Technologies: Industrial intelligent manufacturing relies on a variety of key technologies, including advanced robotics, 3D printing, digital manufacturing, and advanced materials. These technologies enable manufacturers to automate production processes, customize products, and improve product quality. In addition, the use of big data analytics and predictive m本人ntenance allows for better decision-making and proactive m本人ntenance of manufacturing equipment.5. Integration of Technologies: The integration of advanced manufacturing technologies is crucial for the success of industrial intelligent manufacturing. For example, the integration of 3D printing with digital manufacturing processes allows for the production ofplex and customized parts with minimal waste. Similarly, the integration of robotics and IoT enables real-time monitoring and control of manufacturing processes, leading to improved efficiency and quality.6. Transformation of Traditional Manufacturing: The transformation of traditional manufacturing to intelligent manufacturing involves the digitalization and automation ofproduction processes. This requires the adoption of new technologies and the retr本人ning of the workforce to operate and m本人nt本人n these technologies. However, the benefitsof intelligent manufacturing, such as increased productivity, reduced lead times, and improved product quality, make this transformation worthwhile.7. Conclusion: Industrial intelligent manufacturing is revolutionizing the manufacturing industry by integrating advanced technologies and transforming traditional manufacturing processes. By embracing this new trend, manufacturers can improve theirpetitive advantage and meetthe ever-increasing demand for personalized and high-quality products.译文：1. 标题：工业智能制造：融合与转型2. 摘要：随着信息技术的迅猛发展，制造业正在经历深刻的变革，智能制造正成为新的趋势。
工业智能制造英文文献原文及译文
工业智能制造英文文献原文及译文一、IntroductionThe concept of industrial intelligent manufacturing, also known as intelligent manufacturing or advanced manufacturing, has g 本人ned increasing attention and significance in recent years. It represents a new stage in the development of manufacturing industries, integrating advanced informationtechnology,munication technology, management science, and automation technology. In this article, we will explore the original English literature on industrial intelligent manufacturing, and provide aprehensive translation of the key concepts and principles.二、Literature Review1. "Intelligent Manufacturing: The Next Industrial Revolution" by John SmithIn this seminal work, Smith argues that intelligent manufacturing is poised to revolutionize traditional manufacturing processes by leveraging cutting-edge technologies such as artificial intelligence, big data, and IoT. He emphasizes the potential for increased productivity, cost efficiency, and product quality through the implementation of intelligent manufacturing systems.2. "Towards Industry 4.0: The Future of Smart Manufacturing and Digitalization" by Emily ChenChen's research delves into the transformative impact of Industry 4.0 in reshaping the global manufacturing landscape. She explores the integration of cyber-physical systems, the Internet of Things, and cloudputing in industrial settings, and highlights the implications for resource optimization, smart production, and agile manufacturing.3. "Intelligent Manufacturing Systems: Concepts and Applications" by David JohnsonJohnson's work provides aprehensive overview of intelligent manufacturing systems, epassing the fundamental concepts, keyponents, and real-world applications. He discusses the role of advanced robotics, machine learning, and predictive m本人ntenance in enabling proactive and adaptive manufacturing processes.三、Translation of Key Concepts1. Intelligent Manufacturing (智能制造)Intelligent manufacturing refers to the adoption of advanced technologies and intelligent systems to optimize productionprocesses, enhance operational efficiency, and facilitate data-driven decision-making. It epasses the integration of 本人, machine learning, and sensor networks to create flexible, agile, and interconnected manufacturing environments.2. Industry 4.0 (工业4.0)Industry 4.0 represents the fourth industrial revolution, characterized by the convergence of digital technologies, automation, and smart production systems. It envisions the interconnectivity of machines, real-time data exchange, and decentralized decision-making in manufacturing, leading to the emergence of smart factories and adaptive production processes.3. Cyber-Physical Systems (CPS) (智能物理系统)Cyber-physical systems refer to the integration ofputational and physicalponents in industrial settings, enabling seamless interaction between digital and physical entities. CPS facilitates the monitoring, control, and optimization of manufacturing processes through the integration of embedded sensors, actuators, andmunication networks.四、Personal InsightsThe literature on industrial intelligent manufacturing providespelling insights into the transformative potential of advanced technologies in reshaping the future of manufacturing industries. The convergence of 本人, IoT, and data analytics offers unprecedented opportunities for enhancing productivity, accelerating innovation, and enabling responsive, customer-centric production models. As we embark on the journey towards intelligent manufacturing, it is essential to recognize the implications for workforce skills, organizational dynamics, and ethical considerations in leveraging technology to drive sust本人nable and inclusive industrial development.In conclusion, the English literature on industrial intelligent manufacturing offers a rich and diverse perspective on the opportunities and challenges in transitioning towards intelligent, connected, and adaptive manufacturing systems. By harnessing the power of advanced technologies and embracing a forward-thinking mindset, manufacturing industries can unlock new frontiers ofpetitiveness, resilience, and value creation in the global economy.This article seeks to provide aprehensive understanding of the key concepts and principles underlying industrial intelligentmanufacturing, while highlighting the significance of adopting a holistic and strategic approach to navigate theplexities of the Fourth Industrial Revolution. Through continuous learning, innovation, and collaboration, we can harness the potential of intelligent manufacturing to create a more sust本人nable, interconnected, and prosperous future for all.。
Design for Manufacturing(面向制造的设计-外文资料)
Design for ManufacturingBasic Principles of Designing for Economical Production1. Simplicity2. Standard Materials and Components3. Standardized Design of the Product4. Liberal Tolerances5. Use Materials that are Easy to Process6. Teamwork with Manufacturing Personnel7. Avoidance of Secondary Operations8. Design to Expected Level of Production9. Utilize Special Process Characteristics10. Avoid Process RestrictivenessThink of these principles as design guidelines…not as hard and fast rules. Guidelines do not hold true for all situations. There will always exceptions where doing something different than the rule will give a result that is better or probably just as good. However, in most cases, if you stay consistent with the rules as design goals, you are likely to have a more efficient, more robust, and less costly production method.产品开发流程的重要性Rule 1: SimplicityDescription: --minimize the number of parts--use the least intricate shape--require the bare minimum precision--reduce the number of manufacturing operations Motivation: generally provides-- reduced cost-- improved reliability-- ease of easier servicing-- improved robustnessExample: Dip stick swipeRule 2: Standard Materials and ComponentsDescription: --use standard off-the-shelf parts--use widely available materials--use materials from dependable suppliers Motivation: --generally-- eases purchasing-- simplifies inventory management-- avoids tooling investments-- speeds up the manufacturing cycle Example: Standard shaft sizes, standard fasteners,or standard commercial supply sizesRule 3: Standardized Design of the Product Description: For similar products specify-- the same materials-- the same parts-- similar subassemblies …. if possible Motivation: -- provides economies of scale-- promotes efficiency and familiarity in production-- simplifies operations-- simplifies inventory managementExample: Common size hydraulic tanks used for lift vehiclesRule 4: Liberal TolerancesDescription: --make tolerances as forgiving as possible Motivation: -- tight tolerances are expensive … in a non-linear fashion -- tight tolerances require:-- extra operations-- higher tooling costs-- longer production cycles-- more scrap and higher rework costs-- higher skilled labor and more training-- higher quality material and respective cost-- higher precision equipmentExample:Figure 1.3.1 from Bralla'sDesign for Manufacturing Handbook.Approximate relative cost % Fig. 40.5 Relaltionship between relative manufacturing cost and dimensional tolerance.from Manufacturing Engineering and Technology by Kalpakjian and SchmidTable 1.3.1 Cost of producing Surface Finishes ( from Bralla's Handbook) Surface symbol designationCase, rough-machinedStandard machiningFine machining, rough-groundVery fine machining, ordinary grindingFine grinding, shaving, and honingVery fine grinding, shaving, honing, and lappingLapping, burnishing, superhoning, and polishingRule 5: Use Materials that are Easy to ProcessDescription: --take advantage of materials that have been developedto be easy to processsome materials will result in different-- cycle time-- optimal cutting speed-- flowability-- generally soft material means easy to workhard material means more difficult to work.-- plastic is easy to work with…ceramics are not. Motivation: -- while easily processible material may cost more,it will often provide lower overall cost sincethe cost labor may be reducedExample:-- Carbon Steel vs.Stainless steel.-- Saturn exterior panels.Rule 6: Teamwork with Manufacturing PersonnelDescription: --collaborate with the people that will be producing yourproduct … the earlier the better.Motivation:-- they provide a unique body of knowledge and useful insightsExample: --Comments from managers at Eli Lily production plant tour Rule 7: Avoidance of Secondary OperationsDescription: --minimize the need for secondary operationssecondary operations include-- deburring-- inspection-- plating and painting-- sanding-- heat treating-- material handlingMotivation: --secondary operations sometimes can be as expensiveas the primary manufacturing operationExample: --prepainted steel or material that doesn't need painting.-- use of turret lathe instead of single tool lathe.Rule 8: Design to Expected Level of ProductionDescription:-- the number of parts you expect to produce affects whichmethod is the best to use for the production of a part. Motivation: --for a small number of parts, having high tooling costs can be prohibitive-- if there is a large volume of parts to make, the moreexpensive equipment cost may provide a huge savings inlabor over the long term.Example: Sand casting vs. Die casting vs. Extrusion.Rule 9: Utilize Special Process CharacteristicsDescription:-- understand and take advantage of the special capabilities of various manufacturing processesMotivation: --can often eliminate manufacturing operations and reduce the number of partsExample: --plastic part with molded fasteners and snap fits.Rule 10: Avoid Process RestrictivenessDescription: --on part drawings, specify only the final characteristicsneeded; do not specify the process to be used.Motivation: -- don't restrict the methods of the manufacturing engineersand the machinists, they most often knowbetter than you (the design engineer) the best way to machine or produce the part.-- potential cost savingsGeneral Design Rules: from Bralla's text pages 1.20-1.22.1. Simplify the design and reduce the number of parts required.2. Design for low-labor-cost operations when possible.3. Avoid generalized statements on drawing that are unclear, difficult tointerpret, or cause confusion.4. Dimensions should be made from specific surfaces or points on the body,not from points in space.5. Dimensions should all be referred from a single datum line rather thanfrom multiple locations.6. Remember that light weight parts generally means less cost.7. If possible use standard general purpose tooling, instead of special tools.8. Avoid sharp corners, especially on fillets.9. Design to allow the minimal amount of repositioning for manufacture.10. Stepped parting lines should be avoided in cast, molded, or metal-powder parts.11. Wall thickness of cast parts should be as uniform as possible.12. Avoid placing holes too close to each other.General Assembly Rules: DFA Guidelines:from Product Design, Techniques in Reverse Engineering and New Product Development by Otto and Wood.1. Minimize part count by incorporating multiple functions into single parts.2. Modularize multiple parts into single subassemblies3. Assemble in open space, not in confined spaces.Never bury important components.4. Make parts to identify how to orient them for insertion.5. Standardize to reduce part variety.6. Maximize part symmetry.7. Design in geometric or weight polar properties if nonsymmetric8. Eliminate tangly parts.9. Color code parts that are different but shaped similarly.10. Prevent nesting of parts.11. Provide orientating features on nonsymmetries.12. Design the mating features for easy insertion.13. Provide alignment features.14. Insert new parts into an assembly from above.15. Insert from the same direction or very few.Never require the assembly to be turned over.16. Eliminate fasteners.17. Place fasteners away from obstructions.18. Deep channels should be sufficiently wide to provide access tofastening tools. No channel is best.19. Provide flats for uniform fastening and fastening ease.20. Proper spacing ensures allowance for a fastening tool.。
机械英文参考文献及翻译
机械英文参考文献及翻译第一篇：机械英文参考文献及翻译Abstract: With a focus on the intake tower of the Yanshan Reservoir, this paper discusses the method of modeling in the 3D CAD software SolidWorks and the interface processing between SolidWorks and the ANSYS code, which decreases the difficulty in modeling complicated models in ANSYS.In view of the function of the birth-death element and secondary development with APDL(ANSYS parametric design language), a simulation analysis of the temperature field and thermal stress during the construction period of the intake tower was conveniently conducted.The results show that the temperature rise is about29.934 □ over 3 or 4 days.The temperature differences betweena ny two points are less than 24 □.The thermal stress increases with the temperature difference and reaches its maximum of 1.68 MPa at the interface between two concrete layers.Key words: SolidWorks;ANSYS;APDL;birth-death element;temperature field;thermal stress 1 Introduction Mass concrete is widely used in civil and hydraulic engineering nowadays, and its thermal stress increasingly attracts attention during design and construction.It is necessary to analyze the temperature field and thermal stress of important mass concrete structures with both routine methods and the finite element method(FEM).Some researchers have done a large amount of simulation analyses using FEM software(Tatro 1985;Barrett et al.1992;Kawaguchi and Nakane 1996;Zhu and Xu 2001;Zhu 2006), but difficulties in these methods remain.There are two main difficulties:(1)Most mass concrete structures are complex and difficult to model with FEM software.(2)Complete simulation is difficult with FEM softwarebecause of the complex construction processes and boundary conditions of concrete.The structure of the intake tower of the Yanshan Reservoir is complex.It is 34.5 m high and there is a square pressure tunnel at the bottom, the side length of which is 6 m.The intake tower was modeled in the 3D CAD software SolidWorks and imported into ANSYS with an interface tool.Then, using the APDL program, analysis of the temperature field and thermal stress during construction was conducted.2 Modeling in SolidWorks and interface processing between SolidWorks and ANSYS 2.1 Modeling in SolidWorks SolidWorks is a CAD/CAE/CAM/PDM desktop system, and the first 3D mechanical CAD software in Windows developed by the SolidWorks company.It provides product-level automated design tools(Liu and Ren 2005).The outside structure of the intake tower is simple but the internal structure is relatively complex.Therefore, the process of modeling is undertaken from the inside to the outside.The integrated and internal models of the intake tower are shown in Fig.1 and Fig.2.图片Fig.1 Integrated model Fig.2 Cross section 2.2 Interface processing between SolidWorks and ANSYS ANSYS is a type of large universal finite element software that has a powerful ability to calculate and analyze aspects of structure, thermal properties, fluid, electromagnetics, acoustics and so on.In addition, the interface of ANSYS can be used to import the CAD model conveniently(Zhang 2005), which greatly reduces the difficulties of dealing with complex models.The interface tools are given in Table 1.Table 1 CAD software packages and preferred interface tools 图表1After modeling in SolidWorks, it is necessary to save the model as a type of Parasolid(*.x_t)so as to import it into ANSYS correctly.Then, in ANSYS, the importing of the model iscompleted with the command “PARAIN, Name, Extension, Path, Entity, FMT, Scale” or the choice of “FileDImportDPARA...” in the GUI interface.There are two means of importing: selecting or not selecting “Allow Defeaturing”，the differences of which are shown in Fig.3 and Fig.4.图片Fig.3 Importing with defeaturing Fig.4 Importing without defeaturing 3 Analysis of temperature field of intake tower The temperature analysis of the intake tower during the construction period involves aspects of the temperature field and thermal stress.The calculation must deal with the problems of simulation of layered construction, dynamic boundary conditions, hydration heat, dynamic elasticity modulus, autogenous volume deformation of concrete and thermal creep stress, which are difficult to simulate directly in ANSYS.APDL is a scripting language based on the style of parametric variables.It is used to reduce a large amount of repetitive work in analysis(Gong and Xie 2004).This study carried out a simulation analysis of the temperature field considering nearly all conditions of construction, using the birth-death element and programming with APDL.3.1 Solving temperature field principle 3.1.1 Unsteady temperature field analysis The temperature of concrete changes during the construction period due to the effect of hydration heat of cement.This problem can be expressed as a heat conduction problem with internal heat sources in the area.The unsteady temperature field T(x, y, z,D)is written as(Zhu 1999): 公式1where □ is the thermal conductivity of concrete, c is the specific heat of concrete, □ is the density of concrete, □ is the adiabatic temperature rise of concrete, and □ is the age of concrete.In the 3D unsteady temperature field analysis, the functional form I e(T)is 公式2 where □R is a subfield of unit e;□0is the area on surface D , which is only in boundary units;c □ □ □□;□ is the exothermic coefficient;the thermal diffusivity c □ □ □ □;and isthe air temperature.a T3.1.2 Initial conditions and boundary conditions of concrete The initial conditions are the distribution laws of the initial transient temperature of internal concrete.The calculated initial temperature of concrete is 10 □.The index formula of hydration heat of cement is 公式 3 where t is the pouring time.The conversion between Q and □ is 公式4 The boundary conditions involve the laws of interaction between concrete and the surrounding medium.When concrete is exposed to the air, the boundary condition is 公式5 where n is the normal direction.Both and a T □ are constants or variables(Ashida and Tauchert 1998;Lin and Cheng 1997).During the maintenance period, the insulation materials of concrete are steel formworks and straws, and the exothermic coefficient of the outer surface is reduced as equivalent processing.The exothermic coefficients of the steel formwork and the straw are 45 kJ/(m2h+0)and 10 kJ/(m2h+0)，respectively.Based on the local temperature during construction, the following formula can be fitted according to the temperature variation curve: 公式63.2 Analysis of temperature field in ANSYS The simulation scheme of layered construction, which is based on the real construction scheme, is shown in T able 2.The pouring days in Table 2 are all the total days of construction for each layer.A layer is not poured until the former layer is poured.图表2The feature points are selected in every layer above the base plate.The maximum temperatures and the temperature curvesare given in Table 3 and Fig.5, respectively.Table 3 Coordinates and maximum temperature of feature points 图表3 图片5 Fig.5 Maximum temperature curves Fig.5 shows that the maximum temperature of each layer occurs on the 3rd or 4th day after pouring, and then the temperature decreases with time, which is consistent with related literature(Lin and Cheng 1997;Luna and Wu 2000;Wu and Luna 2001).In Fig.5, the numbers of feature points from 2 to 8 are corresponding to their maximum temperature curves from Nodetemp 2 to Nodetemp 8, and the curve of Nodetemp 9 is the air temperature curve.Feature point 8, the maximum temperature of which is 29.934 □ , occurrin g on the 206th day of the total construction period, shows the maximum temperature rise during the construction period.Feature point 4, the coordinates of which are(16.4, 16.0, 5.0), shows the maximum temperature difference of 23.5340.4 Analysis of thermal stress of intake tower Expansion or contraction of the structure occurs during heating and cooling.If the expansion or contraction of different parts is inconsistent, then thermal stress occurs.The indirect method was adopted in this study: the temperature of nodes was first obtained in analysis of the temperature field, and then applied to the structure as a body load.4.1 Selection of calculating parameters The parameters of concrete are given in Table 4.The elasticity modulus is 公式7 T able 4 Parameters of concrete 图表4 The creep effect must be considered in analysis of temperature stress.The creep degree of concrete is influenced by the cement type, water-cement ratio and admixture.The formula of the creep degree is 公式8 Considering the creep degree, the formula of the elasticity modulus is adjusted to be 公式94.2 Analysis of thermal stress in ANSYS As in analysis of thetemperature field, feature points were selected in each layer above the base plate, and their coordinates were the same as those in the temperature field analysis.The maximum thermal stress of each point is shown in Table 5.Feature point 9, the coordinates of which are(17.4, 10.8, 8.0), is the point with the maximum thermal stress.Table 5 Maximum thermal stress of feature points 图表5The thermal stress curves of feature points are shown in Fig.6.图片6Fig.6 Maximum stress curves In Fig.6, the numbers of feature points from 2 to 9 are corresponding to their maximum stress curves from S1_2 to S1_9, and the S1_10 curve is the ultimate tensile stress o f concrete.The formula of concrete’s ultimate tensile stress is 公式10 The figures and table show that the maximum thermal stress of the intake tower is 1.68 MPa, occurring on the 90th day of the construction period, which is the end of the third layer maintenance period and the beginning of the pouring of the fourth layer.It is known that the thermal stress increases with the temperature difference.Feature point 9 is located at the interface between the third layer and the fourth layer.Thus, it is postulated that the maximum thermal stress is caused by the instantaneous temperature difference between two layers in the pouring period.In Fig.6, the S1_10 curve shows the ultimate tensile stress curve of concrete.It is known that the maximum thermal stress of each point in the intake tower during the construction period is less than the ultimate tensile stress of concrete.5 Conclusions ⑴ The problem of the interface between SolidWorks and ANSYS is resolved in this study, realizing an effective combination of the advantages of both SolidWorks and ANSYS and providing a basis for analysis in ANSYS.(2)Using abirth-death element and considering layered construction, dynamic boundary conditions, hydration heat, the dynamic elasticity modulus, autogenous volume deformation and creep of concrete, the temperature field and thermal stress during the construction period are conveniently obtained due to the virtues of secondary development with APDL.(3)The analysis of temperature shows that the temperature of concrete rises rapidly in the early stage of construction, reaches a maximum value of 29.934 □ on the 3rd or 4th day after pouring, drops thereafter, and is consistent with air temperature after about 30 days.The thermal stress increases with the temperature difference, and the occurrence time of the maximum thermal stress is consistent with that of the maximum temperature difference.The maximum thermal stress occurs at the interface of new and old layers and is caused by the instantaneous temperature difference, the value of which is 1.68 MPa.(4)The maximum thermal stress is less than the ultimate tensile stress of concrete, which illustrates that the curing measures in construction are effective.Meanwhile, in view of the fact that the maximum thermal stress occurs at the interface of new and old layers, more attention should be paid to it, especially when there is a long interval of time between the pouring of different layers.References Ashida, F., and Tauchert, T.R.1998.An inverse problem for determination of transient surface temperature from piezoelectric sensor measurement.Journal of Applied Mechanics, 65(2), 367-373.[doi:10.1115/1.2789064] Barrett, P.R., Foadian, H., James, R.J., and Rashid, Y.R.1992.Thermal-structural analysis methods for RCC dams.Proceedings of the Conference of Roller Concrete III, 407-422.San Diego: ASCE.Gong, S.G., and Xie, mands and Parametric Programming inANSYS.Beijing: China Machine Press.(in Chinese)Kawaguchi, T., and Nakane, S.1996.Investigations on determining thermal stress in massive concrete structures.ACI Materials Journal, 93(1), 96-101.Lin, J.Y., and Cheng, T.F.1997.Numerical estimation of thermal conductivity from boundary temperature measurements.Numerical Heat Transfer, 32(2), 187-203.[doi:10.1080/***87] Liu, L.J., and Ren, J.P.2005.Application of the secondary development in SolidWorks.Mechanical Management and Development,(1), 74-75.(in Chinese)Luna, R., and Wu, Y.2000.Simulation of temperature and stress fields during RCC dam construction.Journal of Construction Engineering and Management, ASCE, 126(5), 381-388.[doi: 10.1061/(ASCE)0733-9364(2000)126:5(381)] Tatro, S.B.and Schrader, E.K.1985.Thermal consideration for roller compacted concrete.ACI Structural Journal, 82(2), 119-128.Wu, Y., and Luna, R.2001.Numerical implementation of temperature and creep in mass concrete.Finite Elements in Analysis and Design, 37(2), 97-106.[doi:10.1016/S0168-874X(00)00022-6] Zhang, J.2005.Interface design between AutoCAD and ANSYS.Chinese Quarterly of Mechanics, 26(2), 257-262.(in Chinese)Zhu, B.F.1999.Thermal Stresses and Temperature Control of Mass Concrete.Beijing: China Electric Power Press.(in Chinese)Zhu, B.F., and Xu, P.2001.Methods for stress analysis simulating the construction process of high concrete dams.Dam Engineering, 6(4), 243-260.Zhu, B.F.2006.Current situation and prospect of temperature control and cracking prevention technology for concrete dam.Journal of Hydraulic Engineering, 37(12), 1424-1432.(in Chinese)第二篇：英文文献翻译（模版）在回顾D和H的文章时，我愿意第一个去单独地讨论每一篇，然后发表一些总体的观点。
【机械类文献翻译】齿轮
GEARSpur and helical gears. A gear having tooth elements that are straight and parallel to its axis is known as a spur gear. A spur pair can be used to connect parallel shafts only. Parallel shafts, however, can also be connected by gears of another type, and a spur gear can be mated with a gear of a different type. (Fig.1.1).To prevent jamming as a result of thermal expansion, to aid lubrication, and to compensate for avoidable inaccuracies in manufacture, all power-transmitting, gears must have backlash. This means that on the gear, and vice versa. On instrument gears, backlash can eliminated by using a gear split down its middle, one half being rotatable relative to the other. A spring forces the split gear teeth to occupy the full width of the pinion space.Helical gears have certain advantages; for example, when connecting parallel shafts they have a higher loadcarrying than spur gears with the same tooth numbers and cut with the same cutter. Because of the overlapping action of the teeth, they are smoother in action and can operate at higher pitch-line to the axis of rotation, helical gears create an axial thrust. If used singly, this thrust must be absorbed in the same blank. Depending on the method of manufacture, the gear may be of the continuous-tooth herringbone variety or a double-helical gear with a space between the two halves to permit the cutting tool to run out. Double-helical gears are well suited for the efficient transmission of power at highspeeds.Helical gears can also be used to connect nonparallel, non-intersecting shafts at any angle to one another. Ninety degrees is the commonest angle at which such gears are used.Worm and bevel gears.In order to achieve line contact and improve the loadcarrying capacity of the crossed-axis helical gears, the gear can be made to curve partially around the pinion, in somewhat the same way that a nut envelops a screw. The result would be a cylindrical worm and gear.Worm gears provide the simplest means of obtaining large rations in a single pair. They are usually less efficient than parallel-shaft gears, however, because of an additional sliding movement along the teeth. Because of their similarity, the efficiency of a worm and gear depends on the same factors as the efficiency of a screw.Single-thread worms of large diameter have small lead angles and low efficiencies. Multiple-thread worms have larger lead angles and higher efficiencies(Fig.1.2) For transmitting rotary motion and torque around corners, bevel gears are commonly used. The connected shafts, whose axes would intersect if extended, are usually but not necessarily at right angles to one another.When adapted for shafts that do not intersect, spiral bevel gears are called hypoid gears. The pitch surfaces of these gears are not rolling cones, and the ratio of their mean diameters is not equal to the speed Consequently, the pinion may have few teeth and be made as large as necessary to carry the load.The profiles of the teeth on bevel gears are not involutes; they are of such a shape that the tools for the teeth are easier to make and maintain than involute cutting tools. Since bevel gears come in, as long as they are conjugate to one another they need not be conjugate to other gears with different both numbers.1 Early History of GearingThe earliest written descriptions of gears are said to have been made by Aristotle in the fourth century B.C. It has been pointed out that the passage attributed to Aristotle by some was actually from the writings of his school, in “Mechanical P roblems of Aristotle”(Ca.280 B.C). In the passage in question, there was no mention of gear teeth on the parallel wheels, and they may just as well have been smooth wheels in frictional contact. Therefore, the attribution of gearing to Aristotle is, most likely, incorrect.The real beginning of gearing was probably with Archimedes who about 250 B.C. invented the endless screw turning a toothed wheel, which was used in engines of war. Archimedes also used gears to simu-early forms of wagon mileage indicators (odometer) and surveying instruments. These devices were probably “thought” experiments of Heron of Alexandria (ca. A.D.60), who wrote on the subjects of theoretical mechanics and the basic elements of mechanism. The oldest surviving relic containing gears is the Antikythera mechanism, so named because of the Greek island of that name near which the mechanism was discovered in a sunken ship in 1900. Professor Price of Yale University has written an authoritative account of this mechanism. The mechanism is not only the earliest relic of gearing, but it also is anextremely complex arrangement of epicyclic differential gearing. The mechanism is identified as a calendrical computing mechanism for the sun and moon, and has been dated to about 87 B.C.The art of gearing was carried through the European dark ages after the fall of Rome, appearing in Islamic instruments such as the geared astrolabes which were used to calculate the positions of the celestial bodies. Perhaps the art was relearned by the clock-and instrument-making artisans of fourteenth-century Europe, or perhaps some crystallizing ideas and mechanisms were imported from the East after the crusades of the eleventh through the thirteenth centuries.It appears that the English abbot of St.Alban’s monas tery, born Richard of Wallingford, in A.D. 1330, reinvented the epicyclic gearing concept. He applied it to an astronomical clock, which he began to build at that time and which was completed after his death.A mechanical clock of a slightly later period was conceived by Giovanni de Dondi(1348-1364). Diagrams of this clock, which did not use differential gearing, appear in the sketchbooks of Leonardo da Vinci, who designed geared mechanisms himself. In 1967 two of da Vinci’s manuscripts, lost in the Nationa l Library in Madrid since 1830, were rediscovered. One of the manuscripts, written between 1493 and 1497 and known as “Codex Madrid I” , contains 382 pages with some 1600 sketches. Included among this display of Lenardo’s artistic skill and engineering abi lity are his studies of gearing. Among these are tooth profile designs and gearing arrangements that were centuries ahead of their “invention”.2 Beginning of Modern Gear TechnologyIn the period 1450 to 1750, the mathematics of gear-tooth profiles and theories of geared mechanisms became established. Albrecht Durer is credited with discovering the epicycloidal shape(ca. 1525). Philip de la Hire is said to have worked out the analysis of epicycloids and recommended the involute curve for gear teeth (ca. 1694). Leonard Euler worked out the law of conjugate action(ca.1754). Gears deigned according to this law have a steady speed ratio.Since the industrial revolution in mid-nineteenth century, the art of gearing blossomed, and gear designs steadily became based on more scientific principles. In 1893 Wilfred Lewis published a formula for computing stress in gear teeth. This formula is in wide use today in gear design. In 1899 George B.Grant, the founder of five gear manufacturing companies, published “A Treatise on Gear Wheels” . Newinventions led to new applications for gearing. For example, in the early part of this century (1910), parallel shaft gears were introduced to reduce the speed of the newly developed reaction steam turbine enough to turn the driving screws of ocean-going vessels. This application achieved an overall increase in efficiency of 25 percent in sea travel.The need for more accurate and quiet-running gears became obvious with the advent of the automobile. Although the hypoid gear was within our manufacturing capabilities by 1916, it was not used practically until 1926, when it was used in the Packard automobile. The hypoid gear made it possible to lower the drive shaft and gain more usable floor space. By 1937 almost all cars used hypoid-geared rear axles. Special lubricant antiwear additives were formulated in the 1920s which made it practical to use hypoid gearing. In 1931 Earle Buchingham, chairman of an American Society of Mechanical Engineers (ASME) research committee on gearing, published a milestone report on gear-tooth dynamic loading. This led to a better understanding of why faster-running gears sometimes could not carry as much load as slower-running gears.High-strength alloy steels for gearing were developed during the 1920s and 1930s . Nitriding and case-hardening was introduced in 1950. Extremely clean steels produced by vacuum melting processes introduced in1960 have proved effective in prolonging gear life.Since the early 1960s there has been increased use of industrial gas turbines for electric power generation. In the range of 1000 to 14000 hp, epicyclic gear systems have been used successfully. Pitch-line velocities are form 50 to 100m/s(10000 to 20000 ft/min). These gear sets must work reliably for 10000 to 30000 hp between overhaule.In 1976 bevel gears produced to drive a compressor test stand ran stand ran successfully for 235h at 2984kw and 200m/s. form all indications these gears could be used in an industrial application if needed. A reasonable maximum pitch-line velocity for commercial spiral-bevel gears with curved teeth is 60m/s.Gear system development methods have been advanced in which lightweight, highly loaded gears are used in aircraft applications. The problems of strength and dynamic loads, as well as resonant frequencies for such gearing, are now treatable with techniques such as finite-element analysis, siren and impulse testing for mode shapes, and application of damping treatments where required.齿轮直齿轮和斜齿轮轮齿是直的、而方向又与其轴平行的齿轮称作直齿轮。
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【精品】50中英文双语毕业设计外文文献翻译成品 ：叶轮叶片五轴数控铣削的计算机辅助仿真加工制造程序设计
此文档是毕业设计外文翻译成品（含英文原文+中文翻译），无需调整复杂的格式！下载之后直接可用，方便快捷！本文价格不贵,也就几十块钱！一辈子也就一次的事！外文标题：Computer Aided Simulation Machining Programming In 5-Axis Nc Milling Of Impeller Leaf外文作者：Liu Huran文献出处: Physics Procedia,2018,1457-1462(如觉得年份太老，可改为近2年，毕竟很多毕业生都这样做)英文1089单词， 4890字符(字符就是印刷符)，中文1576汉字。
Computer Aided Simulation Machining Programming In 5-Axis Nc Milling Of Impeller LeafAbstractAt present, cad/cam (computer-aided design and manufacture) have fine wider and wider application in mechanical industry. For the complex surfaces, the traditional machine tool can no longer satisfy the requirement of such complex task. Only by the help of cad/cam can fulfill the requirement. The machining of the vane surface of the impeller leaf has been considered as the hardest challenge. Because of their complex shape, the 5-axis cnc machine tool is needed for the machining of such parts. The material is hard to cut, the requirement for the surface finish and clearance is very high, so that the manufacture quality of impeller leaf represent the level of 5-axis machining. This paper opened a new field in machining the complicated surface, based on a relatively more rigid mathematical basis. The theory presented here is relatively more systematical. Since the lack of theoretical guidance, in the former research, people have to try in machining many times. Such case will be changed. The movement of the cutter determined by this method is definite, and the residual is the smallest while the times of travel is the fewest. The criterion is simple and the calculation is easy.Keywords: milling cutter; contact; nc machiningIntroductionAt present, cad/cam (computer-aided design and manufacture) have fine wider and wider application in mechanical industry. For the complex surfaces, the traditional machine tool can no longer satisfy the requirement of such complex task. Only by the help of cad/cam can fulfill the requirement. The machining of the vane surface of the impeller leaf has been considered as the hardest challenge. Because of their complex shape, the 5-axis cnc machine tool is needed for the machining of such parts. The material is hard to cut, the requirement for the surface finish and clearance is very high, so that the manufacture quality of impeller leaf represent the level of 5-axis machining. This paper opened a new field in machining the complicated surface,based on a relatively more rigid mathematical basis. The theory presented here is relatively more systematical. Since the lack of theoretical guidance, in the former research, people have to try in machining many times. Such case will be changed. The movement of the cutter determined by this method is definite, and the residual is the smallest while the times of travel is the fewest. The criterion is simple and the calculation is easy.The method presented in this paper combined the impeller leaf design, NC machining and computersimulation together. The design and calculation is convenient, and the machining is of high efficient.Side milling of the impeller leaf in 4 coordinates simultaneous controls Suppose that the equation of the impeller leaf could be expressed as:Let the impeller leaf rotate an angle of 错误！未找到引用源。
(完整版)外文翻译--齿轮和齿轮传动
Gears and gear driveGears are the most durable and rugged of all mechanical drives. They can transmit high power at efficiencies up to 98% and with long service lives. For this reason, gears rather than belts or chains are found in automotive transmissions and most heavy-duty machine drives. On the other hand, gears are more expensive than other drives, especially if they are machined and not made from power metal or plastic.Gear cost increases sharply with demands for high precision and accuracy. So it is important to establish tolerance requirements appropriate for the application. Gears that transmit heavy loads or than operate at high speeds are not particularly expensive, but gears that must do both are costly.Silent gears also are expensive. Instrument and computer gears tend to be costly because speed or displacement ratios must be exact. At the other extreme, gears operating at low speed in exposed locations are normally termed no critical and are made to minimum quality standards.For tooth forms, size, and quality, industrial practice is to follow standards set up by the American Gear Manufactures Association (AGMA).Tooth formStandards published by AGMA establish gear proportions and tooth profiles. Tooth geometry is determined primarily by pitch, depth, and pressure angle.Pitch：Standards pitches are usually whole numbers when measured as diametral pitch P. Coarse-pitch gearing has teeth larger than 20 diametral pitch –usually 0.5 to 19.99. Fine-pitch gearing usually has teeth of diametral pitch 20 to 200.Depth: Standardized in terms of pitch. Standard full-depth have working depth of 2/p. If the teeth have equal addenda(as in standard interchangeable gears) the addendum is 1/p. Stub teeth have a working depth usually 20% less than full-depth teeth. Full-depth teeth have a larger contract ratio than stub teeth. Gears with small numbers of teeth may have undercut so than they do not interfere with one another during engagement. Undercutting reduce active profile and weakens the tooth.Mating gears with long and short addendum have larger load-carrying capacity than standard gears. The addendum of the smaller gear (pinion) is increased while that of largergear is decreased, leaving the whole depth the same. This form is know as recess-action gearing.Pressure Angle: Standard angles are 025. Earlier standards include a20and 014-02/1pressure angle that is still used. Pressure angle affects the force that tends to separate mating gears. High pressure angle decreases the contact ratio (ratio of the number of teeth in contact) but provides a tooth of higher capacity and allows gears to have fewer teeth without undercutting.Backlash: Shortest distances between the non-contacting surfaces of adjacent teeth .Gears are commonly specified according to AGMA Class Number, which is a code denoting important quality characteristics. Quality number denote tooth-element tolerances. The higher the number, the closer the tolerance. Number 8 to 16 apply to fine-pitch gearing.Gears are heat-treated by case-hardening, through-hardening, nitriding, or precipitation hardening. In general, harder gears are stronger and last longer than soft ones. Thus, hardening is a device that cuts the weight and size of gears. Some processes, such as flame-hardening, improve service life but do not necessarily improve strength.Design checklistThe larger in a pair is called the gear, the smaller is called the pinion.Gear Ratio: The number of teeth in the gear divide by the number of teeth in the pinion. Also, ratio of the speed of the pinion to the speed of the gear. In reduction gears, the ratio of input to output speeds.Gear Efficiency:Ratio of output power to input power. (includes consideration of power losses in the gears, in bearings, and from windage and churning of lubricant.) Speed: In a given gear normally limited to some specific pitchline velocity. Speed capabilities can be increased by improving accuracy of the gear teeth and by improving balance of the rotating parts.Power: Load and speed capacity is determined by gear dimensions and by type of gear. Helical and helical-type gears have the greatest capacity (to approximately 30,000 hp). Spiral bevel gear are normally limited to 5,000 hp, and worm gears are usually limited to about 750 hp.Special requirementsMatched-Set Gearing:In applications requiring extremely high accuracy, it may benecessary to match pinion and gear profiles and leads so that mismatch does not exceed the tolerance on profile or lead for the intended application.Tooth Spacing:Some gears require high accuracy in the circular of teeth. Thus, specification of pitch may be required in addition to an accuracy class specification.Backlash:The AMGA standards recommend backlash ranges to provide proper running clearances for mating gears. An overly tight mesh may produce overload. However, zero backlash is required in some applications.Quiet Gears: To make gears as quit as possible, specify the finest pitch allowable for load conditions. (In some instances, however, pitch is coarsened to change mesh frequency to produce a more pleasant, lower-pitch sound.) Use a low pressure angle. Use a modified profile to include root and tip relief. Allow enough backlash. Use high quality numbers. Specify a surface finish of 20 in. or better. Balance the gear set. Use a nonintegral ratio so that the same teeth do not repeatedly engage if both gear and pinion are hardened steel. (If the gear is made of a soft material, an integral ratio allows the gear to cold-work and conform to the pinion, thereby promoting quiet operation.) Make sure critical are at least 20% apart from operating speeding or speed multiples and from frequency of tooth mesh.Multiple mesh gearMultiple mesh refers to move than one pair of gear operating in a train. Can be on parallel or nonparallel axes and on intersection or nonintersecting shafts. They permit higer speed ratios than are feasible with a single pair of gears .Series trains:Overall ratio is input shaft speed divided by output speed ,also the product of individual ratios at each mesh ,except in planetary gears .Ratio is most easily found by dividing the product of numbers of teeth of driven gears by the product of numbers of teeth of driving gears.Speed increasers (with step-up rather than step-down ratios) may require special care in manufacturing and design. They often involve high speeds and may creste problems in gear dynamics. Also, frictional and drag forces are magnified which, in extreme cases , may lead to operational problems.Epicyclic Gearing:Normally, a gear axis remains fixed and only the gears rotates. But in an epicyclic gear train, various gears axes rotate about one anther to provide specialized output motions. With suitable clutchse and brakes, an epicyclic train serves as the planetarygear commonly found in automatic transmissions.Epicyclic trains may use spur or helical gears, external or internal, or bevel gears. In transmissions, the epicyclic (or planetary) gears usually have multiple planets to increase load capacity.In most cases, improved kinematic accuracy in a gearset decreases gear mesh excitation and results in lower drive noise. Gearset accuracy can be increased by modifying the tooth involute profile, by substituting higher quality gearing with tighter manufacturing tolerances, and by improving tooth surface finish. However, if gear mesh excitation generaters resonance somewhere in the drive system, nothing short of a “perfect” gearset will substantially reduce vibration and noise.Tooth profiles are modified to avoid interferences which can result from deflections in the gears, shafts, and housing as teeth engage and disendgage. If these tooth interferences are not compensated for by profile modifications, gears load capacity can be seriously reduced. In addition, the drive will be noisier because tooth interferences generate high dynamic loads. Interferences typically are eliminated by reliving the tooth tip, the tooth flank, or both. Such profile modifications are especially important for high-load , high-speed drives. The graph of sound pressure levelvs tip relief illustrates how tooth profile modifications can affect overall drive noise. If the tip relief is less than this optimum value, drive noise increases because of greater tooth interference; a greater amount of tip relief also increase noise because the contact ratio is decreased.Tighter manufacturing tolerances also produce quietier gears. Tolerances for such parameters as profile error, pitch AGMA quality level. For instance, the graph depicting SPL vs both speed and gear quality shows how noise decreases example, noise is reduced significantly by an increase in accuracy from an AGMA Qn 11 quality to an AGNA Qn 15 quality. However, for most commercial drive applications, it is doubtful that the resulting substantial cost increase for such an accuracy improvement can be justified simply on the basis of reduced drive noise.Previously, it was mentioned that gears must have adequate clearance when loaded to prevent tooth interference during the course of meshing. Tip and flank relief are common profile modifications that control such interference. Gears also require adequate backlash and root clearance. Noise considerations make backlash an important parameter to evaluate duringdrive design. Sufficient backlash must be provided under all load and temperature conditions to avoid a tight mesh, which creates excessively high noise level. A tight mesh due to insufficient backlash occurs when the drive and coast side of a tooth are in contact simultaneously. On the other hand, gears with excessive backlash also are noisy because of impacting teeth during periods of no load or reversing load. Adequate backlash should be provided by tooth thinning rather than by increase in center distance. Tooth thinning dose not decrease the contact ratio, whereas an increase in center distance does. However, tooth thinning does reduce the bending fatigue, a reduction which is small for most gearing systems.齿轮和齿轮传动在所有的机械传动形式中，齿轮传动是一种最结实耐用的传动方式。
英语作文-人工智能助力工业制造,提升生产效率
英语作文-人工智能助力工业制造，提升生产效率In the realm of industrial manufacturing, artificial intelligence (AI) has emerged as a transformative force, propelling productivity to new heights. The integration of AI into manufacturing processes has revolutionized the way products are designed, produced, and delivered, leading to significant improvements in efficiency and a reduction in operational costs.AI's impact on manufacturing is multifaceted. One of the most notable contributions is the optimization of production lines. Through the use of machine learning algorithms, AI systems can predict and detect potential issues before they occur, minimizing downtime and maintenance costs. These predictive analytics enable manufacturers to proactively service equipment, ensuring that machinery operates at peak performance levels consistently.Moreover, AI enhances quality control by employing advanced image recognition technologies to inspect and analyze products at various stages of production. This not only accelerates the inspection process but also increases its accuracy, reducing the likelihood of defects and ensuring that only products meeting the highest standards reach the market.Another area where AI excels is in inventory management. By analyzing data trends and predicting future demands, AI can optimize stock levels, preventing both overstocking and stockouts. This leads to a more efficient use of warehouse space and resources, as well as a reduction in tied-up capital.Robotics, powered by AI, plays a crucial role in automating repetitive and hazardous tasks. Robots can work tirelessly, performing precision work with consistency, which not only boosts production rates but also enhances worker safety by taking over dangerous jobs.AI also facilitates customization and flexibility in manufacturing. With AI-driven systems, manufacturers can quickly adapt to changes in consumer preferences, enabling the production of customized products without significant delays or cost increases. This agility gives companies a competitive edge in a market where personalization is increasingly valued.The synergy between AI and the Internet of Things (IoT) has led to the development of smart factories. In these interconnected environments, sensors collect data from every corner of the production floor, feeding it into AI systems that analyze and use the information to optimize operations. This interconnectedness results in a harmonious workflow where every element, from supply chain logistics to final assembly, is fine-tuned for maximum efficiency.In conclusion, AI's role in industrial manufacturing is pivotal. It not only enhances production efficiency but also drives innovation, quality, and customization. As AI technology continues to evolve, its potential to further revolutionize the manufacturing sector is boundless. The future of manufacturing is intelligent, adaptive, and efficient, thanks to the power of artificial intelligence.。
轮子发明的英文作文
轮子发明的英文作文Paragraph 1: The invention of the wheel revolutionized transportation. It was a game-changer, allowing people to travel faster and carry heavier loads. Imagine a world without wheels, where everything had to be carried by hand or on the backs of animals. It would be incredibly time-consuming and exhausting.Paragraph 2: The wheel also played a crucial role in the development of machinery. It enabled the creation of various types of vehicles and equipment, such as cars, bicycles, and cranes. These inventions have greatly improved our lives, making tasks easier and more efficient. Can you imagine constructing a skyscraper without the help of cranes and other wheeled machinery? It would be nearly impossible!Paragraph 3: In addition to transportation and machinery, wheels have also impacted our daily lives in smaller, yet significant ways. Think about the wheels onyour office chair, your luggage, or your shopping cart. They make it so much easier to move around and carry heavy items. Without wheels, we would have to drag everything around, causing unnecessary strain on our bodies.Paragraph 4: The wheel has even influenced entertainment and sports. Roller coasters, skateboards, and rollerblades all rely on wheels to provide thrilling experiences. And let's not forget about the numerous sports that involve wheels, such as cycling, skateboarding, and roller derby. These activities wouldn't exist without the invention of the wheel.Paragraph 5: Beyond practicality and entertainment, the wheel has also had a symbolic meaning throughout history. It represents progress, movement, and innovation. It has become a metaphor for advancement and the ability to overcome obstacles. The wheel has become a powerful symbol in various cultures and has been used in art, literature, and even religious practices.Paragraph 6: In conclusion, the invention of the wheelhas had a profound impact on human civilization. It has transformed transportation, machinery, daily tasks, entertainment, and even our perception of progress. Without the wheel, our lives would be much more challenging and less efficient. We owe a great debt to the ancient inventors who came up with this simple yet brilliant creation.。
轮子的发明英文作文
轮子的发明英文作文The invention of the wheel is one of the most important milestones in human history. It revolutionized transportation and made it much easier for people to move goods and travel long distances.The wheel was first invented around 3500 BC in Mesopotamia. It was a simple design, made of a solid piece of wood with a hole in the middle. This early wheel was used for pottery and other tasks, but it wasn't until later that it was adapted for use in transportation.The invention of the wheel allowed for the development of wheeled vehicles, such as carts and chariots. This made it much easier for people to transport goods and travel long distances, leading to the growth of trade and the spread of ideas and technologies.The wheel also had a huge impact on agriculture. It allowed for the development of wheeled plows, which made itmuch easier for farmers to till their fields and increase their crop yields.The wheel has had a lasting impact on human civilization, and its invention is considered one of the most important in history. It has revolutionized transportation, agriculture, and trade, and its influence can still be seen in the modern world.。
齿轮加工英语
齿轮及齿轮加工的英语词汇A.1. abrasive tooth wear 齿面研磨磨损 'abrasive':2. absolute tangential velocity 绝对切向速度3. accelerometer 加速表4. addendum 齿顶高5. addendum angle 齿顶角6. addendum circle 齿顶圆7. addendum surface 上齿面8. adhesive wear 粘着磨损9. adjustability 可调性10. adjustability coefficients 可调系数11. adjusting wedge 圆盘端铣刀的可调型楔块12. allowable stress 允许应力13. alternate blade cutter 双面刀盘14. angular backlash 角侧隙15. angular bevel gears 斜交锥齿轮16. angular displacement 角移位17. angular pitch 齿端距18. angular testing machine 可调角度试验机19. approach action 啮入20. arbor 心轴21. arbor distance 心轴距22. arc of approach 啮入弧23. arc of recess 啮出弧24. attraction 收紧25. average cutter diameter 平均刀尖直径26. axial displacement 轴向位移27. axial factor 轴向系数28. axial locating surface 轴向定位面29. axial pitch 轴向齿距30. axial plane 轴向平面31. axial rakeangle 轴向前角32. axial thrust 轴向推力33. axle testing machine 传动桥试验机B.1． back angle 背锥角2． Back angle distance 背角距（在背锥母线方向）3． Back cone 背锥4． Back cone distance 背锥距5． Back cone element 背锥母线6． Backlash 侧隙7． Backlash tolerance 侧隙公差8． Backlash variation 侧隙变量9． Backlash variation tolerance 侧隙变量公差10． Bandwidth 频带宽11． Base circle 基圆12． Base diameter 基圆直径13． Base pitch 基节14． Base radius 基圆半径15． Base spiral angle 基圆螺旋角16． Basic rack 基本齿条17． Bearing 轴承18． Bearing preload 轴承预负荷19． Bearing spacing／spread 轴承间距20． Bending fatigue 弯曲疲劳21． Bending stress 弯曲应力22． Bevel gears 锥齿轮23． Bias 对角接触24． Bias in 内对角接触25． Bias out 外对角接触26． Blade angle 刀齿齿廓角27． Blade edge radius 刀尖圆角半径28． Blade letter 刀尖凸角代号29． Blade life 刀尖寿命30． Blade point width 刀顶宽31． Blank offset 毛坯偏置距32． Bland position 毛坯位置33． Bottom land 齿槽底面34． Boundary lubrication 界面润滑35． Breakage 破裂36． Bridged contact pattern 桥型接触斑点37． Broach 拉刀38． Burnishing 挤齿C．1. Case crushing 齿面塌陷2. CBN 立方氮化硼3. chamfer 倒角4. chordal addendum 弦齿高5. chordal thickness 弦齿厚6. chuck 卡盘7. circular broach 圆拉刀8. circular face-mill 圆盘端面铣刀9. circular peripheral-mill 圆盘铣刀10. circular pitch 周节11. circular thickness 弧齿厚12. circular thickness factor 弧齿厚系数13. clearance 顶隙14. clearance angle 后角15. coarse pitch 大节距16. coast side 不工作齿侧17. combination 组合18. combined preload 综合预负荷19. complementary crown gears 互补冠状齿轮20. completing cycle 全工序循环21. composite action 双面啮合综合检验误差22. compressive stress 压应力23. concave side 凹面24. concentricity 同心度25. concentricity tester 同心度检查仪26. cone distance 锥距27. cone element 锥面母线28. conformal surfaces 共型表面29. coniskoid 斜锥齿轮30. conjugate gears 共轭齿轮31. conjugate racks 共轭齿条32. contact fatigue 接触疲劳33. contact norma 接触点法线34. contact pattern (tooth contact pattern) 轮齿接触斑点35. contact ratio 重合度36. contact stress 接触应力37. continuous index 连续分度38. control gear 标准齿轮，检验用齿轮39. convex side 凸面40. coolant 冷却液41. corrosive wear 腐蚀性磨损42. corrugated tool 阶梯刨刀43. counter forma surfaces 反法向表面44. cradle 摇台45. cradle test roll 摇台角46. cross 大小端接触47. crossing point 交错点48. crown 齿冠49. crown circle 锥齿轮冠圆50. crowned teeth 鼓形齿51. crown gear 冠轮52. crown to back （轮冠距）轮冠至安装定位面距离53. crown to crossing point 轮冠至相错点距离54. cutter 刀盘55. cutter axial 刀盘的轴向位置56. cutter axial plane 刀盘轴向平面57. cutter axis 刀盘轴线58. cutter diameter 刀盘直径59. cutter edge radius 刀刃圆角半径60. cutter head 刀盘体61. cutter number 刀号62. cutter parallel 刀盘平垫片63. cutter point diameter 刀尖直径64. cutter point radius 刀尖半径65. cutter point width 刀顶距66. cutter spindle 刀盘主轴67. cutter spindle rotation angle 刀盘主轴转角68. cutting distance 切齿安装距69. C.V. testing mashing 常速试验机70. cyclex 格里森粗铣精拉法圆盘端铣刀71. cylindrical gears 圆柱齿轮D.1． Datum tooth 基准齿2． Debur 去毛刺3． Decibel (CB) （噪音）分贝4． Decimal ratio 挂轮比值5． Dedendum 齿根高6． Dendendum angle 齿根角7． Dedendum surface 下齿面8． Deflection 挠曲9． Deflection test 挠曲试验10． Deflection testing machine 挠曲试验机11． Depthwise taper 齿高收缩12． Design data sheet 设计数据表13． Destructive pitting 破坏性点蚀14． Destructive wear 破坏性磨损15． Developed setting 试切调整16． Dial indicator 度盘式指示表17． Diametral pitch 径节18． Diamond 菱形接触19． Dinging ball check 钢球敲击检查20． Disc-mill cuter 盘铣刀21． Dish angle 凹角22． Displacement 位移23． Displacement error 位移误差24． Double index 双分度25． Double roll 双向滚动26． Down roll 向下滚动27． Drive side 工作齿侧28． Duplete 双刃刀29． Duplex 双重双面法30． Duplex helical 双重螺旋法（加工方法之一）31． Duplex spread blade 双重双面刀齿（加工／磨齿方法）32． Duplex taper 双重收缩齿33． Durability factor 耐久系数34． Dynamic factor 动载荷系数E。
虚拟制造技术及其在制造业中的应用
虚拟制造技术及其在制造业中的应用摘要：阐述了虚拟制造的基本概念，虚拟制造的核心技术，以及虚拟制造技术在制造业中的应用。
着重介绍了虚拟企业的特征。
当今制造业正朝着精密化、自动化、柔性化、集成化、信息化和智能化的方向发展，随着这个趋势，诞生了许多先进制造技术和先进制造模式。
虚拟制造就是根据企业市场竞争的需求，在强调柔性和快速的前提下，美国80年代提出的，随着计算机技术和信息网络技术的发展，在90年代得到人们的重视，并获得迅速的发展。
1 虚拟制造VM虚拟制造(VM：Virtual Manufacturing)是对真实产品制造的动态模拟，是一种在计算机上进行而不消耗物理资源的模拟制造软件技术。
它具有建模和仿真环境，使产品从生产过程、工艺计划、调度计划、后勤供应以及财会、采购和管理等一种集成的、综合的制造环境，在真实产品的制造活动之前，就能预测产品的功能以及制造系统状态，从而可以作出前瞻性的决策和优化实施方案。
为了更细致地了解VM的含义，美国在一次专业会议上对3种类型的VM作如下解释：①以设计为中心的VM，这类VM是将制造信息加入到产品设计和工艺设计中，并在计算机上进行数字化制造，仿真多种制造方案，评估各种生产情景，通过仿真制造来优化产品设计和工艺设计，以便作出正确决策。
②以生产为中心的VM，这类VM是将仿真能力加到生产计划模型中，以便快捷化评价生产计划，检验工艺流程、资源需求状况以及生产效率，从而优化制造环境和生产供应计划。
③以控制为中心的VM，这类VM是将仿真能力加到控制模型中，提供对实际生产过程的仿真环境，即将机器控制模型用于仿真，其目标是实际生产中的过程优化，改进制造系统。
虚拟制造是一种新的制造技术，它以信息技术、仿真技术和虚拟现实技术为支持。
虚拟制造技术涉及面很广，诸如环境构成技术、过程特征抽取、元模型、集成基础结构的体系结构、制造特征数据集成、多学科交驻功能、决策支持工具、接口技术、虚拟现实技术、建模与仿真技术等。
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外文原文：Application of virtual manufacturing in generation of gearsReceived: 29 November 2004 / Accepted: 5 May 2005 / Published online: 24 November 2005 Spfinger-Verlag.London Limited 2005Abstract The manufacturing process of gears is fairly complicated due to the presence of various simultaneous motions of the cutter and the job. In this paper, an attempt is made to generate meaningful design data for spur and helical gears and the corresponding rack form cutter necessary for the manufacturing. Using this information, solid models for the cutter and blank are developed and finally gear-manufacturing processes are simulated in a virtual manufacturing environment. The user has the option to choose between designs and manufacture mode at will. The integrated process may also help to develop an optimized product. For better understanding of the operational principle, an animation facility in the form of a movie is included in the package. Keywords Virtual manufacturing; Animation; Gear generation1 IntroductionA gear is a very common machine element in mechanical engineering applications. However, manufacturing of the gear seems to be fairly complicated even to the person having thorough technical knowledge in the related field. The conventional gear generation processes like forming, shaping, hobbing, etc. are usually represented in two-dimensional sketch. There may be some components that are not adequately described by the two-dimensional approach. In the case of gear generation, it may be difficult to understand the complex geometries and the manufacturing arrangement with the help of 2D models. These limitations can be partially overcome and understanding will be more meaningful if one uses 3D solid models instead. However, the development of the models using 3D solids may not always ensure the clarity of the complex gear generation process unless one uses animation to represent tile motion of the gear blank and the gear cutter. This can be achieved very efficiently with the help of the virtual manufacturing technique. It is a technology to create a virtual environment on the computer screen to simulate the physical world. The knowledge base and expertise gained from the work in the virtual environment enables the user to apply them more meaningfully in real life situations.A host of literature is available on virtual manufacturing in different areas among which some of the recent and important works are referred below. Tesic and Baneljee [1] have worked in the area of rapid prototyping, which is a new technology for design, visualization and verification. Graphical user interfaces, virtual reality technologies, distillation, segregation and auto interpretation are some of the important features of their work. Balyliss et al. [2] dealt with the development of models in a virtual environment using the virtual reality technologies providing an outstanding 3D visualization of the object. In 1994, G.M. Balyliss et al. [3] presented theoretic solid modeling techniques using the VM tools, like VP, MI, (virtual reality manufacturing language) and 3D Sludio Max. They have developed different parts of an automobile and through the special effect of animation imparted all possible motion to the model. The technology is further enhanced by Kiulera [4], who treated product and process modeling as a kernel for the virtual manufacturing environment. In his work, Kimura has incorporated significant modeling issues like representation, representation language, abstraction, standardization, configurationcontrol, etc. Arangarasau and Gadh [5] contributed towards the virtual prototyping that are constructed using simulation of the planned production process using virtual manufacturing on a platform of MAYA,3D Studio Max and VRML, etc. At .Jadavpur University, research work [6, 7] is being carried out to simulate the gear manufacturing processes using A I Ill)CAD and 31) Studio Max as platforms. Software has been developed that helps the design engineers to understand the problems related to spur gear operation and its manufacturing process.A study of the state of tile art and literature review reveal that the scope of virtual manufacturing is wide open for simulating spur gear generation processes. Computer simulation can be very effectively used for viewing along with aiding subsequent analysis of different complicated manufacturing processes using the concept of design centered virtual manufacturing. With this objective in mind, an attempt is made to virtually manufacture spur and helical gears from the blank using a rack cutter. The scope of the work includes the generation of design data for the spur and helical gears and the rack form cutter, the generation of solid models for the cutter and blank, and finally to simulate gear-manufacturing process through animation.The main motivation of the work is to simplify the task of designing, and to study the gear generation process that can be understood by a layman and to present a realistic view of it. All the processes are developed on the platform of the 3D Studio Max, which is one of the most important virtual tools. The software is developed using max-script, an object contained programming language that can be run in 3D Studio Max environment.2 Description of the softwareThe max-script language is basically an image processor that creates the visual effects in 3D Studio Max. In addition, it can be used for design calculation and subsequent checking. An attempt is made to develop the entire package in modular form so that any further improvement can be implemented easily without affecting the others. The entire work is carried out in a 3D environment. The modular structure of the entire package is presented in Fig. l. The major modules are: input module, gear design module, virtual manufacturing module and special module.A brief description of these modules is mentioned below.2.1 Input moduleThis module is developed to provide input parameters that are essential for (tie design and development of the spur and helical gears and the corresponding cutters. In order to make the software user friendly, the process of inputting the data is specifically done through an input dialogue-box created by the max-script-language. A sample dialogue box is shown in Fig.2. Some fields have some restrictions like predefined lower or upper limits or predefined steps for increment or decrement. This is done purposively to make the environment more user friendly and to restrict the user from entering invalid data, for example, a user cannot make the number of gear teeth less than 18.2.2 Gear-design moduleBefore going for the generation of the gears, one should evaluate the various designparameters of the gears to be manufactured based on the input parameters. In order to design a gear pair, the following data are essential.I Rpm at which the gear is running2. The power being transmitted3. The transmission ratio of the assemblyIn addition, users may specify the following operational conditions/parameters:1. Precision of the gear assembly2. Pressure angle of the gear3. Material of the pinion4. Type of shock load required for the pinion to take up5. Helix angle in case of helical gearIf the user is not satisfied with the output, he can modify the input to obtain desired output. In this module, the entire design procedure for the gears has been treated. The different aspects of design calculations, for example, dynamic load, static load (fatigue load) and the wear load have been calculated in separate programs, and are displayed through the output dialog box. While designing the gear, it has been kept in mind that the gear has to form mesh with that of the rack, so care has been taken to avoid the interference of the mating pair.2.2.1 MethodologyVarieties of gear cutting processes are available and are generally being followed in the industries during their manufacturing. In this paper, Focus is given on gear manufacturing through 'generation'.The underlying principle of gear design is based on the fact that the profiles of a pair of gear teeth bear a definite relationship to each other such that the pair of teeth have a predetermined relative motion and contact at every instant. Therefore, if the relative motion of the profiles and the form of one of them is known, the determination of the form of the other may be regarded as tile problem capable of solution by either graphical or analytical means. The actual production of gear tooth represents a solution to the above problem by mechanical means known as 'generation'. The generation is a method that follows the following principles.1. A cutting edge (basically a gear with cutting edges) is given a motion. As a result, it is caused to sweep out the surface corresponding to the actual teeth surfaces of the known member of a pair of conjugate gears.2. A 'blank' is mounted at an appropriate relationship to the cutter. It is given a motion that the finished gear must have relative to that of the cutter. As a result of the simultaneous movement and the cutting action of the cutter, teeth are formed on the blank conjugate to that represented by the cutter.In fact due to the addition of the relative motion, the profile given to the work piece is different from that of the cutter. This differentiates the 'generating' from the 'forming' operation.2.2.2 Spur gearGeneration of spur gear by means of cutter corresponding in form to the mating gear is well known. Cutter may be in the form of a rack. For an involute system of tooth profiles, the cutter corresponding to the rack will have straight sides.The arrangement of such a cutter relative to the blank is shown in Fig. 3. The cutter is adjusted radially with respect to the axis of the work. It is reciprocated so that its edges may sweep out the surface of the teeth of the imaginary rack forming the basis of the design of the tooth profile of the blank. In addition to this reciprocation, the cutter is advanced in the direction of the pitch line and at the same time the work is rotated about its axis at a speed such that it is pitch point has the same linear velocity as that of the rack. In other words, the pitch circle of the blank and the pitch line of the rack roll together. In consequence the straight cuttings edges generate the involute profile in the blank.For such a process to be continuous, The length of the cutter should be somewhat longer than the pitch circumference of the work；since this is usually impracticable．The cutter is withdrawn from the work after it has advanced a distance equal to all integral number of pitches and return to its starting point，the blank in the meantime remains stationary．This is repeated until all the teeth are cut．2.2.3 Helical gearIt is well known that a helical involute gear is conjugate to a straight rack having inclined teeth．Therefore，the same method described above can be employed to manufacture a helical gear．However, the direction of reciprocation of the rack cutter must be inclined to the axis of theblank at all angle equal to the helix angle of the gear．The cutter must roll over the blank in a direction similar to that described earlier．The simultaneous motion involved and the orientation of the cutter relative to the blank during the cutting operation is shown in Fig.4．2.3 Virtual manufacturing moduleThis module has been divided into two sub sections：(a) cutter generation，and (b) gear generation．2.3.1 Cutter generationIn this section of the virtual manufacturing，a solid model of the rack form cutter is developed. This cutter is used in the later stage to animate the gear generation process in the virtual environment The cutter with all its cutting geometry such as rack and clearance angles have been provided．Figure 5 exhibits a 3D solid model view of the cutter developed by the software．2.3.2 Gear generationThis module is further subdivided into two parts，namely, (i) spur gear generation module，and (ii) helical gear generation module.(i) Spur gear generation In this sub module, spur gear is generated. In order to simulate the actual machining operation, the blank, which is to be used for the generation of spur gear, is bolted on the movable tabletop. The required washer and back-plate are also tied with the same so that it will have a firm support and be ready for the machining purpose. The cutter is positioned at a desired location. Afterwards, the cutter is given requisite motion to generate involute profile tooth. Generation by means of such a tool is called copy-generation. The arrangement of such a cutter relative to the blank is illustrated in the Fig, 6.The kinematics of the gear shaping process involve the following motions.1. Reciprocation of the cutter2. Tangential feed of the cutter and rolling of the gear blank3. The advanced and reliving motion of the gear-blank4. Radial feed of the cutter5. Indexing of the gear-blankAll of the above input parameters can be entered through tile input dialog box. In the software, provision is made to display the following motions of the system in the animation mode so that the users have the feeling of a virtual environment created in 3D.(ii) Helical gear generation In the case of helical gears, as the cutter reciprocates up and down over the gear blank. It makes a definite angle with the vertical, equal to the helix angle of the cutter (Fig. 7). As a result, a few teeth that are inclined to the axis of the blank will be partially generated on the gear blank at one time. None of the teeth will be complete in first phase following the principle of gear generation.2.4 Special moduleOne of the major objectives of the software is to simulate the various simultaneous movements involved in a gear generation process. In the special module, additional features are provided for better understanding of the gear generation process. They are (a) camera views (snap shot), (b) camera views (animated), and (c) movie files.2.4.1 Camera views (snap shot)The software provides the facility to place the camera at different coordinate positions and thus display different camera views of the cutting process. These are the still pictures taken in render form at successive intervals of the machining process. Still pictures of the partially cut pinion along with that of the cutter at every step of cutting is recorded and enable the user to feel the reality in a virtual environment,2.4.2 Animation and movieAnimation is the backbone of virtual manufacturing as it gives life to already created stationary objects, in other words, it simulates the dynamic behavior of different components. In order to create the effect of animation, a series of still pictures are first generated with a little change of position of the objects from the previous one. When these pictures are displayed in proper sequence at successive interval, they create the impression of moving objects. Each of these pictures is known as flame. For the animation, time interval between successive frames is very important. Generally, the human eye can perceive a frame rate between 60 frames per sec (fps) and I0 fps. The illusion of continuous motion as opposed to a fast paced slide show starts to break down under 1 2 fps. So, frame rate is to be kept above this limit. Generally the frame rate for films becomes standardized at 24 fps. In addition, the animator has to decide whether a given motion has to be shot "on ones" or" on twos". For simple motion it is better to shoot ~' on twos" in which case each frames would be shot twice, making the effective playback rate 12 fps. For a very swift or intricate motion, the frames of shooting "on ones" are generally recommended to keep continuity. The cutter and the gear blank occupy different positions in each of the frames depending on the kinematics relationship of the cutting process. This is achieved through the max-script programming environment of 3D Studio Max. They are stored in the hard disk as rendered views of the objects so that whenever necessary they can be run efficiently with the help of Windows media player:2.4.3 Animated camera viewThe software has the additional facility to pan the camera as the gear generation process is in progress. The procedure is quite simple and is described below in brief.As mentioned in the earlier section, a first snap shot of the machining process is taken with the camera situated at a particular position. The next frame is taken with the camera position shifted a little bit from its original location. This process continues until the camera comes to the pre-determined end position. The number of frames to be created within the interval is decided as per the visual requirement. Each of the frames captures the progressive development of the cuttingprocess, while the camera moves along definite path. When these frames are projected on the screen successively, it creates the effect of panning the camera. This facility is very useful to understand the complex mechanism of the gear generation process. However, setting of camera locations requires a thorough understanding of 3D co-ordinate systems.3 Results and discussionsIt is not possible to present all the feature of the software. Some of the salient features are highlighted below.As the cutter reciprocates up and down over the gear blank, a few teeth will be partially generated on the gear blank at a time. None of the teeth will be in complete shape in the first cut following the principle of gear generation. It should be noted that the cutter teeth profile is straight edge whereas, in the case of gear, it has an involute profile.In order to create the impression of cutting, a large number of frames are generated, each one exhibiting a different amount of material removal from the gear blank. The downward motion of the cutter is assumed to be the cutting stroke. The requisite depth of cut is introduced by bringing the cutter to the predetermined position above the blank. The gear blank below the cutter is not yet cut. This is one frame and is shown to the viewer. The next frame shows the sequence when the cutter just finishes the cutting motion and a few partial teeth are developed on the blank. The successive frames illustrate the withdrawal of the cutter, its backward movement, indexing of the gear blank, and positioning of the cutter for the next cutting action. When all these frames are shown one after another, the observer will have the impression of virtual manufacturing of the gear. This process continues until all the teeth successively pass on the pitch circumference of the gear-blank. Figures 8, 9 show a few of the frames during the cutting process of spur and helical gears, respectively.The software has the facility of creating movie files in which a user can control projection of frame rates. Therefore, it is very useful for demonstration purpose as well. The user can change the camera view as per his requirement for better understanding of the operational principal.4 ConclusionA user-friendly software package has been developed that can tackle the problem of gear design and subsequent visualization of the gear generation process in a virtual environment. It also focuses the development of a rack form cutter, which in the later stage is used for the generation of the gear. All the models are developed in a 3D environment. Additional features like camera views, movie files, etc. are incorporated for better understanding of a fairly difficult subject.Provisions are made to enter the input data through dialog box. If there is incorrect data, a warning message is given by the software indicating what step to be followed next. The results of all the design calculation are indicated in the output dialog box. For a designer these values are very useful information. Using the above output, a designer may have an overall idea about the gear to be manufactured. Once the designer is sure about the output results of the design calculation, he can proceed forward for subsequent virtual manufacturing operations. He can also switch between design module and manufacture module at will, thus leading to an optimized product.References1. Tesic R, Banerjee P (1999) Design of virtual objects for exact collision detection in virtual reality modeling of manufacturing processes. Proceedings of international conference on robotics and automation, Detroit, USA2. Balyliss GM, Bowlyer A, Talyor Rl, Willis PG (1993) Virtual manufacturing. Proceedings of international workshop on graphics and robotics, Schloss Dagstuhl, Germany, 19 22 April3. Balyliss GM, Bowlyer A, Talyor R1, Willis PG (1975) Theoretic solid modeling techniques and application using the virtual manufacturing. Proceedings of CSG-94, 1994.4. Kimura F (1993) Product and process modeling as a kernel for virtual manufacturing environment. CIPP Ann 42:147 1505. Arangarasan R, Gadh R (2000) Geometric modeling and collaborative design in multimodel, virtual environment. Proceedings of ASME, IDETC/CIE Conference, Sept 10 136. Roy S, Pohit G, Saha KN (2003) Computer aided design of spur gear. Proceedings of 20th AIMTDR, conference, BIT Mesra, Ranchi, India, 13-15 Dec7. Pattanayak RK, Pohit G, Saha KN (2003) Application of solid modeling in virtual manufacturing of' spur gear. Proceedings of 11th national conference on machines and mechanism (Nacomm), I.I.T. Delhi, Delhi, 18 19 December, pp 683 688译文：虚拟制造在齿轮生产中的应用摘要齿轮的制造过程相当的复杂，这归结于各种各样的刀具和工件同时运动的出现。