车辆工程汽车离合器的外文文献翻译
湖北文理学院
毕业设计(论文)英文翻译
题目有限元热分析的陶瓷离合器
专业车辆工程
班级Xxx
姓名Xxxx
学号2010138xx
指导教师
职称Xxx 副教授
2014年2月25日
Fethermal analysis of a ceramic clutch
1. Introduction
Abrasive dry running vehicle clutches are force closure couplings. Torque and speed transmission are ensured by the frictional force generated between two pressed surfaces. Reasons for the application of ceramic as a friction medium include good heat and wear resistance properties, which provide the opportunity to drive higher pressures, and a low density. Thus, an increasing power density is enabled with a parallel minimization of construction space.
Measurements with a first prototype of a clutch disk using ceramic facings were performed at Karlsruhe University in a laboratory specialized in passenger car drive system testing. In the course of analysis the finite element (FE) model was to be constructed with the knowledge of measurement data and measurement conditions. Calculations were intended to determine the temperature distribution of the clutch disk and its environment at each moment in time corresponding to measurements. It is essential to be familiar with the temperature range in order to examine the wear characteristics of the system. Thus, important information is derived from measurement data. In critical load cases, the highest expected temperatures must be forecast in space and time in order to protect measuring instruments close to the location of heat generation.
The goal of this study is to analyze and modify the clutch system to provide better operating conditions by improving the heat conduction and convection of the system or to increase the amount of the energy converted into frictional heat. Furthermore, it is desired to find better design solutions for more efficient clutch systems.
Calculations were performed by the Cosmos Design Star software. During model development, great care had to be taken for proper simplification of geometry, the selection of element sizes, and the correct adjustment of time steps due to the substantial hardware requirements for transient calculations. Changes in thermal parameters such as the surface heat convection coefficient and thermal load had to be taken into consideration on an on-going basis in terms of time and location. The two sides of the analyzed test clutch system can only be managed by two independent models linked by heat partition,
according to the hypothesis that the contact temperature must be identical on both sides while there is proper contact between them and its value must be adjusted by iteration. Calculations revealed that the heat partition changed by cycle and it differed along the inner and outer contact rings. As a result of the different cooling characteristics between the ceramic and steel side, a heat ?ow is launched from the ceramic side to the steel side. This heat flow was also determined by iteration, its value also changes by cycle and differs along the inner and outer contact rings.
2. First prototype of a clutch using engineering ceramics as friction material
The examined clutch disk was developed according to the “specific ceramic” product development process established at the Institute for Product Development (IPEK) at the University of Karlsruhe. This development process already has the possibility for connection to a real transmission shaft; further, it has a cushion spring device for the facings allowing good start behaviour. Abrasive clutches must comply with the following basic requirements:
●high torque transmission according to high friction coefficients,
●high comfort (no vibrations through self-induced chattering),
●homogeneous temperature distribution,
●low wear characteristic.
A critical element of the switch is the abrasive disk.With regard to the design utmost care must be taken to select the right material. A high and constant friction coefficient,，wear resistance and thermal resistance are desired characteristics. The clutch disk has instead of the generally applied ring-shaped abrasive inlet two rows of SSIC (as sintered) ceramic pellets. These pellets are placed on 6 separate segments. The segments are ?xed to the central hub by rivets. Each segment consists of 4 plates, 2 working as facing springs and 2 as carriers.
3. Measurements
Measurements were performed at the department of power train development of the Institute for Product Development (IPEK) at the Karlsruhe University (TH) Research
University, where a category IV component test rig is used for tests of new frictional materials and examinations of new materials in real clutch disks. Real conditions are applied by the simulation of driving resistance (e.g. starting in the plane, starting at the hill). It is a component test rig leveled on the fourth position of the tribological testing environment.
In order to give an idea of dimensions: the equipment length is about 4-5m. The two electric motors and the axial force are controlled independently by computer; thereby many operational states can be realized. This enables the equipment to complete a myriad of tribological measurements all while properly modeling the operation of a clutch disk in a passenger car. It is also equipped with an automatic IT measurement system. Measurable quantities include the following:
●two heavy-duty electric motors (150 KW, Baumuller DS 160L-305),
●device suitable for exerting axial force,
●torque meter (Manner Sensortelemetrie MF100),
●axial force meter,
●steel disk in friction,
●replaceable head to affix the device to be tested,
●temperature along two different radii at 0.4mm below the abrasive surface of the steel
disk (Omega HJMTSS-IM100U-150-2000,J-typeiro-constantan thermocouples),
●revolutions per minute for both sides (Polytene LSV 065).
The greatest challenge out of these is temperature measurement as we would like to know the temperature of the revolving steel disk. The two thermoelements placed in the steel disk forward data to the computer through a wireless blue tooth system and are placed 0.4mm below the abrasive surface of the steel disk on the two opposite arcs of the clutch disk.
3.2. Measurement process
Due to component analyses and cost reduction only one side of the clutch disk is mounted with ceramic facings. Thus, the clutch disk and its fitting will be referred to as the ceramic side, and the abrasive steel disk with its environment revolving together will be referred to as the steel side. In the course of measurements, data were collected at a sampling frequency of 100 and 1000HZ. Measurements were conducted according to the
time curves.
The measurement starts by increasing the revolutions per minute of the steel side (the driving side) to a specific value (1500 rpm here). Then the ceramic side (the driven side), held at zero rpm, is pushed towards the steel disk and the axial force is applied until a designated value is reached (nominally 4200N here). Upon reaching the designated axial force the ceramic side is released and the two sides start to synchronize. A few seconds after synchronization, the axial load is discontinued and after some time both the steel and the ceramic sides—revolving at the same speed—are slowed down. This is deemed to be one measurement cycle. Ten cycles are completed in the course of a single measurement. During application of the axial force the ceramic side is held at zero rpm until the desired force is reached to ensure synchronization occurs at nearly the same time of each cycle. This is unfavorable from the viewpoint of both measurements and calculations. Measurements are usually conducted by changing only 3 parameters: the speed, the axial load and the inertia. The following figures are applied in various combinations:
●speed n: 700, 1100 and 1500 (rpm),
●axial force F: 4200, 6400 and 8400 (N) and
●inertia I: 1, 1.25 and 1.5 (kgm2).
Experimental measurements are launched with approx.10-15 min intervals, during which the system cools down to about 30-40 1C. This makes calculations difficult, as the exact temperature distribution of the system is not known at the commencement of the measurement. However, it can be assumed that a period of 10-15min is sufficient for a nearly homogeneous temperature distribution to be produced. The parameters for the following simulation have been chosen for an intermediate case with a speed n =1500 rpm, an axial force F = 4200 N and an inertia I = 1 kg m2.
4. Calculations of heat generation
The mechanical energy consumed during the friction of two bodies is transformed into heat. The generated heat can be calculated by the following simple formula: Q =μ·ν·F [W] .
where m is the the frictional coefficient; v is the sliding velocity; F is the force perpendicularly compressing the surfaces. And the heat flux density per surface unit is
q=μ·ν·p [Wm2].
where p is the the pressure calculated as a ratio of the force and the contacting surface. As the ceramic tablets are placed at two different radii along the clutch disk, the heat generated must be calculated separately for each radii. Sliding can be divided into two sections. In the first section, the ceramic side is kept in a stationary position by braking, meanwhile the axial load is increased; therefore compression changes in the course of time while the speed difference between the two sides is constant. In the second section (at synchronization) the speed difference is equalized while the force value is constant, so velocity changes in time. On the basis thereof, the heat generated is
.
The nominal contact area is the aggregate of the contacting surfaces of the 24 and 18 ceramic tablets on the given ring. The diameter of ceramic tablets is:
.
Calculations were performed for the load case to be characterized by the following parameters:
.
Based on experimental measurements a constant friction coefficient of 0.4 was established.
.
The velocity can be calculated with the knowledge of the radius and the speed.
.
Surface pressure can be calculated as a ratio of the axial force and the contacting surface. This produces the same figure for each ceramic pellet, assuming an even load distribution.
.
Thus, the maximum values of the generated heat are
.
In the first section of sliding, the generated heat is rising due to the increase of the load force; in the second section, it is decreasing due to the equalization of the speed difference. It is necessary to know the time of each sliding section in order to be able to specify the generated heat time curve. These can be determined from measurement data series. Synchronization time can be easily determined from the speed of the ceramic side. Speed increase is linear. Force increase is non-linear. For the sake of simplicity, force increase was substituted by a straight line in calculations so that the area below the straight line is nearly identical with the area measured below the curve. Thus, the time difference between the two terminal points of the straight line is the time of the first sliding section.
The above-mentioned method was applied for each cycle and their average was specified. Based on these results, the following values were determined for sliding times:
.
Now the time curve of heat generation can be produced. The same curve was used in each cycle as there were no significant differences between parameters in each cycle. The generated heat-calculated this way-will appear as thermal load in the thermal model. It must be distributed appropriately between the contacting surfaces by taking into
consideration heat partition. Heat partition requires the contact temperatures to be identical at both surfaces. Correct adjustment requires repeated iterations.
有限元热分析的陶瓷离合器
1 引言
磨料空转车辆离合器是力封闭联轴器。扭矩和高速传输被压紧表面之间产生的摩擦力所保证。应用陶瓷是因为它作为摩擦介质具有好耐热和耐磨损性能，提供了机会以驱动更高的压力，以及一个低的密度。因此，一个提功率密度启用了一个平行的最小化建筑空间。
测量使用陶瓷饰面离合器盘的第一个原型在卡尔斯鲁厄大学的一个实验室专门从事客车驱动系统进行了测试执行。在分析过程中的有限元（FE）模型是将与测量数据和测量条件的知识所构成。计算的目的是要确定在离合器盘上温度的分布以及环境中的在每一时刻的及时测量目。至关重要的是熟悉的温度范围，为了检验该系统的耐磨特性。因此，重要信息从测量数据中得出。在临界负载的情况下，预计最高温度必须在时间和空间上进行预测，为保护接近发热体的位置测量工具的。
本研究的目的是分析和修改该离合器系统通过改进，以提供更好的工作条件热传导和系统或增加转化成摩擦热的能量的对流。此外，人们希望找到更有效的更好的离合器系统设计方案。
计算是由宇宙星空的设计的软件进行的。在模型开发阶段，非常谨慎，必须采取几何元素，选择适当的简化尺寸，并且由于正确调整的时间步长大量的硬件要求瞬态计算。热物性参数的改变，如表面热对流化系数和热负荷，必须考虑到到在一个持续的基础上在时间和地点方面。离合器系统的分析测试这两方面，只能通过加热隔板连接的两个独立的模型来管理，根据该假说认为，接触温度必须是在两个相同的双方，同时他们要有适当接触，其价值需通过迭代来进行调整。计算显示，该热分区按周期变化，它沿不同的内，外接触环。在不同的冷却特性下，在陶瓷和钢之间的结果是不同的，热流从陶瓷侧面向钢侧流动。此热流也通过迭代确定;它的价值也改变了周期和不同沿着所述内和外接触环。
2 采用工程陶瓷作为摩擦材料的第一个原型机
这款检查过的离合器盘是根据“特定的陶瓷”产品而开发的，此材料的研发过程在流程在卡尔斯鲁厄大学的Institute for Product Development (IPEK)杂志上发表过。此开发过程已经具有的可能性，用于连接到一个真实的传动轴；甚至，它为面板有一个好的初始行为起到一个很好的缓冲作用。磨料配件必须符合以下基本要求：
1.根据高摩擦系数高扭矩传递
2.高舒适度（通过自感应抖动无共振）
3.均匀的温度分布
4.低磨损特性
开关的一个关键因素是摩擦面.在设计极限方面，必须谨慎采取选择合适的材料。高而恒定的摩擦系数，耐磨损和耐热性是理想的特性。离合器圆盘能代替通常应用环形磨料入口两排SSIC的（烧结）陶瓷颗粒。这些小球被放置在6个单独的段位。该段由铆钉固定到中心轮毂。每个段由4片组成，2个工作面对着弹簧和2个作为载体。
3 测量
3.1 测量设备
测量是在卡尔斯鲁厄大学（TH）研究型大学的动力传动系完成的，同时也是用于测试新的摩擦材料和新材料在实际离合器片中检测的地方。真实情况是通过驱动电阻的仿真应用（例如，开始在平面上，开始于山）的试验装置。这是一个组件试验台夷为平地在摩擦测试环境的第四位。为了给维度的概念：设备长度大约4-5m 。两台电动机和轴向力是由计算机独立控制;因此许多运营可实现的状态。这使得设备来完成一个摩擦学测量无数，而所有正确建模在乘用车上的离合器盘的操作。它还配备用自动的IT测量系统。可测量的量包括以下内容：
1.2个重型电机（150千瓦，Baume米勒DS160L-305）
2.设备适用于施加轴向力
3.扭力计（Sensortelemetrie MF100）
4.轴力计
5.钢盘的摩擦
6.可更换的头部贴上设备进行测试
7.温度沿两个不同的半径处为0.4mm以下的钢盘（欧米茄HJMTSS-IM100U-磨料表面
150-2000，J铁康铜热电偶）
8.每分钟转数为双方（Polytec LSV065）。
这里最大的挑战是这些我们想知道的旋转钢盘面上温度的测量。两个热元件放置在钢盘通过无线蓝牙数据转发给计算机系统和被放置为0.4mm以下的研磨面钢盘上的两个相对的圆弧的离合器盘。
3.2 测量过程
为了测量由组分分析和降低成本的一侧离合器盘安装用陶瓷衬片，由此，离合器磁盘及其配件将被称为陶瓷侧，而磨具钢盘与它的环境一起旋转会简称为钢侧。在测量时，数据的过程中收集在100和1000Hz 的采样频率。
在测量开始通过增加每转钢侧（驱动侧）的分钟为一个特定值（这里是1500转）。然后在陶瓷侧（驱动侧），在保持零转速下被推向钢盘和轴向力应用，直到一个指定的值为止（名义上4200N 在这里）。当到达所指定的轴向力的陶瓷侧是释放和双方开始同步。几秒钟在同步之后，在轴向载荷终止和后一段时间都在钢和陶瓷两侧绕转在相同的速度会慢下来。这被视为一个测量周期。十个周期中的一个过程中完成单次测量。在应用程序中的轴向力陶瓷侧被保持在零转速，直至所需的力达到以确保发生同步于几乎每种相同的时间周期。这是不利的从两者的观点出发，测量目和计算。测量通常通过进行仅改变3个参数：速度，轴向载荷和惯性。下面的数字是应用于各种组合：
1.转速n ：700 ，1100和1500（RPM ）
2.轴向力F ： 4200 ，6400和8400（N ）
3.惯量I ：1 ，1.25和1.5（ kgm 2为单位）
实验测量与约推出,10-15分钟的时间间隔，在此期间，系统冷却到约30-40摄氏度。这使得计算变得很困难，因为确切的该系统的温度分布是不知道的开始测量。然而，可以假定经过一段时间的10-15分钟就足够了一个几乎均一要产生的温度分布。下面的模拟已经选择了一个中间的情况下用转速n=1500转，一轴向力F=4200N 和一个惯量I=1kgm 2。
4 计算两个摩擦过程中所消耗的机械能体被转化成热量
所产生的热量可计算由下列简单的公式：Q =μ·ν·F [W]，其中μ为摩擦系数， v 是滑动速度， F 是垂直压缩表面上的力。和每单位表面的热通量密度q=μ·ν·p
[Wm 2]，其中p 是计算的力的比率的压力和的接触表面。作为陶瓷片被放置在两个不同的半径沿离合器盘，所产生的热量必须分别计算每个半径。滑动可分为两部分。在第一部，所述陶瓷侧被保持在一个固定的位置由制动，同时在轴向负荷增大，因此在时间的过程中压缩的变化，而速度双方的差异是恒定的。在第二部分（在同步）的转速差进行均衡,而力值是恒定的，所以在时间的速度变化。基础物所产生的热量是：
nom A t p t v Q 111)()(???=μ nom A t p t v Q 222)()(???=μ
名义接触面积是24的接触表面的聚合和18陶瓷平板电脑在给定的半径。陶瓷小块的直径是:
mm d pellet 16=
计算进行了负荷情况的特点是以下参数:
2
max max 142001500kgm I N F rpm
n ===
基于实验测量的恒定摩擦0.4系数成立。
)(4.0const =μ
速率可以通过速度和半径的知识来计算： s
m r n v s
m r n v m
r m
r 116028.1460207.0094.02max max 21max max 121=??==??===ππ 表面压力可以计算为轴向力的比率和接触表面。这产生相同的数字的每个陶瓷颗粒，假设即使负载分布。
则有： MPa A A F p nom
nom 496.021max max =+= 这样的话，最大的集中热值就是：
W Q W
Q 7919003619.049000114.014177004825.04960008.144.0max 2max 1=???==???=
在滑动的第一部分，所产生的热上升，由于负载力的增加;在第二部分中，它是减小由于速度差的均衡。这是要知道各滑动部分的时间，以可以指定所产生的热量时间曲线。这些可以是从测量数据序列来确定。同步时间可以很容易地从陶瓷侧的速度来决定。速度的提升是线性的。力的增加是非线性的。为了简单起见，力增加在被取代的由直线计算使下面的直线的面积近相同的曲线下测量的面积。因此，时间直线的两个端点之间的差异是第一滑动部的时间。
将上述方法应用于每个周期和他们的平均被指定。基于这些结果，下面的值被确定为滑动时间：
应力时间8.2:11=t t s
同步时间92.0:22=t t s
现在发热的时间曲线可以产生。该相同的曲线被用在每一个周期，因为有在每一个循环参数之间没有显著差异。所产生的热量，计算出这种方式，会出现在热模型的热负荷。它必须分布的接触表面通过考虑适当地之间考虑热分区。热分区需要接触的温度是相同的两个表面上。正确的调整需要反复迭代。
工业工程 外文期刊 翻译_
Adrian Payne & Pennie Frow A Strategic Framework for Customer Relationship Management Over the past decade, there has been an explosion of interest in customer relationship management (CRM) by both academics and executives. However, despite an increasing amount of published material,most of which is practitioner oriented, there remains a lack of agreement about what CRM is and how CRM strategy should be developed. The purpose of this article is to develop a process-oriented conceptual framework that positions CRM at a strategic level by identifying the key crossfunctional processes involved in the development of CRM strategy. More specifically, the aims of this article are ?To identify alternative perspectives of CRM, ?To emphasize the importance of a strategic approach to CRM within a holistic organizational context, ?To propose five key generic cross-functional processes that organizations can use to develop and deliver an effective CRM strategy, and ?To develop a process-based conceptual framework for CRM strategy development and to review the role and components of each process.
车辆工程汽车离合器的外文文献翻译
经典文档下载后可编辑复制 湖北文理学院 毕业设计(论文)英文翻译 题目有限元热分析的陶瓷离合器 专业车辆工程 班级Xxx 姓名Xxxx 学号2010138xx 指导教师 职称Xxx 副教授 2014年2月25日
Fethermal analysis of a ceramic clutch 1. Introduction Abrasive dry running vehicle clutches are force closure couplings. Torque and speed transmission are ensured by the frictional force generated between two pressed surfaces. Reasons for the application of ceramic as a friction medium include good heat and wear resistance properties, which provide the opportunity to drive higher pressures, and a low density. Thus, an increasing power density is enabled with a parallel minimization of construction space. Measurements with a first prototype of a clutch disk using ceramic facings were performed at Karlsruhe University in a laboratory specialized in passenger car drive system testing. In the course of analysis the finite element (FE) model was to be constructed with the knowledge of measurement data and measurement conditions. Calculations were intended to determine the temperature distribution of the clutch disk and its environment at each moment in time corresponding to measurements. It is essential to be familiar with the temperature range in order to examine the wear characteristics of the system. Thus, important information is derived from measurement data. In critical load cases, the highest expected temperatures must be forecast in space and time in order to protect measuring instruments close to the location of heat generation. The goal of this study is to analyze and modify the clutch system to provide better operating conditions by improving the heat conduction and convection of the system or to increase the amount of the energy converted into frictional heat. Furthermore, it is desired to find better design solutions for more efficient clutch systems. Calculations were performed by the Cosmos Design Star software. During model development, great care had to be taken for proper simplification of geometry, the selection of element sizes, and the correct adjustment of time steps due to the substantial hardware requirements for transient calculations. Changes in thermal parameters such as the surface heat convection coefficient and thermal load had to be taken into consideration on an on-going basis in terms of time and location. The two sides of the analyzed test clutch system can only be managed by two independent models linked by heat partition,
外文文献翻译：汽车的发展
The development of automobile As the world energy crisis and the war and the energy consumption of oil -- and are full of energy in one day someday it will disappear without a trace. Oil is not inresources. So in oil consumption must be clean before finding a replacement. With the development of science and technology the progress of the society people invented the electric car. Electric cars will become the most ideal of transportation. In the development of world each aspect is fruitful especially with the automobile electronic technology and computer and rapid development of the information age. The electronic control technology in the car on a wide range of applications the application of the electronic device cars and electronic technology not only to improve and enhance the quality and the traditional automobile electrical performance but also improve the automobile fuel economy performance reliability and emission spurification. Widely used in automobile electronic products not only reduces the cost and reduce the complexity of the maintenance. From the fuel injection engine ignition devices air control and emission control and fault diagnosis to the body auxiliary devices are generally used in electronic control technology auto development mainly electromechanical integration. Widely used in automotive electronic control ignition system mainly electronic control fuel injection system electronic control ignition system electronic control automatic transmission electronic control ABS/ASR control system electronic control suspension system electronic control power steering system vehicle dynamic control system the airbag systems active belt system electronic control system and the automatic air-conditioning and GPS navigation system etc. With the system response the use function of quick car high reliability guarantees of engine power and reduce fuel consumption and emission regulations meet standards. The car is essential to modern traffic tools. And electric cars bring us infinite joy will give us the physical and mental relaxation. Take for example automatic transmission in road can not on the clutch can achieve automatic shift and engine flameout not so effective improve the driving convenience lighten the fatigue strength. Automatic transmission consists mainly of hydraulic torque converter gear transmission pump hydraulic control system electronic control system and oil cooling system etc. The electronic control of suspension is mainly used to cushion the impact of the body and the road to reduce vibration that car getting smooth-going and stability. When the vehicle in the car when the road uneven road can according to automatically adjust the height. When the car ratio of height low set to gas or oil cylinder filling or oil. If is opposite gas or diarrhea. To ensure and improve the level of driving cars driving stability. Variable force power steering system can significantly change the driver for the work efficiency and the state so widely used in electric cars. VDC to vehicle performance has important function it can according to the need of active braking to change the wheels of the car car motions of state and optimum control performance and increased automobile adhesion controlling and stability. Besides these appear beyond 4WS 4WD electric cars can greatly improve the performance of the value and ascending simultaneously. ABS braking distance is reduced and can keep turning skills effectively improve the stability of the directions simultaneously reduce tyre wear. The airbag appear in large programs protected the driver and passengers safety and greatly reduce automobile in collision of drivers and passengers in the buffer to protect the safety of life. Intelligent electronic technology in the bus to promote safe driving and that the other functions. The realization of automatic driving through various sensors. Except some smart cars equipped with multiple outside sensors can fully perception of information and traffic facilities
工业工程外文翻译
毕业设计(论文)英文翻译 学生姓名：学号： 所在学院：经济与管理学院 专业：工业工程 设计(论文)题目：好孩子推车事业部总装线生产线优化设计指导教师：
The Methods for Solving the Problem of Balancing an Assembly Line Currently, along with the market changing, some forerunners production mode got an extensive application in the manufacturing industry. How raise a whole efficiency of assembling the production line, reduce a work preface in the ware, and pursue to synchronize production is valued by more and more people. The production of manufacturing industry is most likely after carrying on subdividing to turn of have another a work preface flowing water to turn a continuous homework production line, at this time because of division of homework, the time of each work preface operates can't completely the same in theoretically and physically, this phenomenon that certainly will lead to a work preface homework burden unbalance. In addition to losing, result in the meaningless man-hour also result in a great deal of work preface pile up, sometimes will result in the abeyance of production line. Assembly line balance is a kind of means and method for resolving an above-mentioned problem, it is to make all work carry on equally, carrying on a research to the homework, carrying on a measurement to time, making the Assembly line moving smoothly. The assemble is the last link of production, assembling process mainly with the gearing of parts, tightly solid in lord; secondly allied connect, press to pack and add to note various work to lie quality and quality examination of work preface, sometimes still want to choose to pack according to the customer intention. The whole assemble homework is complicated, belonging to a labor an intensive type engineering. Therefore, the balance of exaltation assembly line has important realistic meaning to exaltation's production efficiency of the car assembly line. The assembly line equilibrium problem is the long-lost type of a type of typical model the combination is excellent to turn a problem, particularly is for random, many the assembly line equilibrium problem of target, solve to the satisfaction seldom more on a certain degree. Mainly is divided into the following 3 aspects to the research of assembly line equilibrium problem currently: Give the rhythm of the assembly line certainly beg minimum work station number, usually in the assembly line of design and install the stage carry on; The minimum work station given to settle assembly line number, make the rhythm of assembly line minimum, to already exist of the production line carry on adjust excellent turn; Get in work station number and rhythm of assembly line excellent turn under certain condition, all sparse assemble the burden of on-line work station, give the staff member a kind of fair feeling. Because the balance of
汽车制动系统(机械、车辆工程毕业论文英文文献及翻译)
Automobile Brake System汽车制动系统 The braking system is the most important system in cars. If the brakes fail, the result can be disastrous. Brakes are actually energy conversion devices, which convert the kinetic energy (momentum) of the vehicle into thermal energy (heat).When stepping on the brakes, the driver commands a stopping force ten times as powerful as the force that puts the car in motion. The braking system can exert thousands of pounds of pressure on each of the four brakes. Two complete independent braking systems are used on the car. They are the service brake and the parking brake. The service brake acts to slow, stop, or hold the vehicle during normal driving. They are foot-operated by the driver depressing and releasing the brake pedal. The primary purpose of the brake is to hold the vehicle stationary while it is unattended. The parking brake is mechanically operated by when a separate parking brake foot pedal or hand lever is set. The brake system is composed of the following basic components: the “master cylinder” which is located under the hood, and is directly connected to the brake pedal, converts driver foot’s mechanical pressure into hydraulic pressure. Steel “brake lines” and flexible “brake hoses” connect the master cylinder to the “slave cylinders” located at each wheel. Brake fluid, specially designed to work in extreme conditions, fills the system. “Shoes” and “pads” are pushed by the slave cylinders to contact the “drums” and “rotors” thus causing drag, which (hopefully) slows the c ar. The typical brake system consists of disk brakes in front and either disk or drum brakes in the rear connected by a system of tubes and hoses that link the brake at each wheel to the master cylinder (Figure). Basically, all car brakes are friction brakes. When the driver applies the brake, the control device forces brake shoes, or pads, against the rotating brake drum or disks at wheel. Friction between the shoes or pads and the drums or disks then slows or stops the wheel so that the car is braked.
汽车离合器课程毕业设计外文文献翻译、中英文翻译、外文翻译
CLUTCH The engine produces the power to drive the vehicle. The drive line or drive train transfers the power of the engine to the wheels. The drive train consists of the parts from the back of the flywh eel to the wheels. These parts include the clutch, th e transmission, the drive shaft, and the final drive assembly (Figure 8-1). The clutch which includes the flywheel, clutch disc, pressure plate, springs, pressure plate cover and the linkage necessary to operate the clutch is a rotating mechanism between t he engine and the transmission (Figure 8-2). It operates through friction which comes from contact between the parts. That is the reason why the clutch is called a friction mechanism. After engagement, the clutch must continue to transmit all the engine torque to the transmission depending on the friction without slippage. The clutch is also used to disengage the engine from the drive train whenever the gears in the transmission are being shifted from one gear ratio to another. To start the engine or shift the gears, the driver has to depress the clutch pedal with the purpose of disengagement the transmission from the engine. At that time, the driven members connected to the transmission input shaft are either stationary or rotating at a speed that is slower or faster than the driving members connected to the engine crankshaft. There is no spring pressure on the clutch assembly parts. So there is no friction between the driving members and driven members. As the driver lets loose the clutch pedal, spring pre ssure increases on the clutch parts. Friction between the parts also increases. The pressure exerted by the springs on the driven members is controlled by the driver through the clutch pedal and linkage. The positive engagement of the driving and driven members is made possible by the friction between the surfaces of the members. When full spring pressure is applied, the speed of the driving and driven members should be the same. At the
道路与桥梁专业外文翻译中英对照
道路与桥梁专业外文翻译 中英对照 Jenny was compiled in January 2021
本科毕业设计（论文） 专业名称：土木工程专业（道路与桥 梁） 年级班级：道桥08-5班学生姓名： 指导教师： 二○一二年五月十八日 专业外文翻译
Geometric Design of Highways The road is one kind of linear construction used for travel. It is made of the roadbed, the road surface, the bridge, the culvert and the tunnel. In addition, it also has the crossing of lines, the protective project and the traffic engineering and the route facility. The roadbed is the base of road surface, road shoulder, side slope, side ditch foundations. It is stone material structure, which is designed according to route's plane position .The roadbed, as the base of travel, must guarantee that it has the enough intensity and the stability that can prevent the water and other natural disaster from corroding. The road surface is the surface of road. It is single or complex structure built with mixture. The road surface require being smooth, having enough intensity, good stability and anti-slippery function. The quality of road surface directly affects the safe, comfort and the traffic. Highway geometry designs to consider Highway Horizontal Alignment, Vertical Alignment two kinds of linear and cross-sectional composition of coordination, but also pay attention to the smooth flow of the line of sight, etc. Determine the road geometry, consider the topography, surface features, rational use of land and environmental protection factors, to make full use of the highway geometric components of reasonable size and the linear combination. Design The alignment of a road is shown on the plane view and is a series of straight lines called tangents connected by circular. In modern practice it is common to interpose transition or spiral curves between tangents and circular curves.
工业工程英文文献及外文翻译
附录 附录1：英文文献 Line Balancing in the Real World Abstract:Line Balancing (LB) is a classic, well-researched Operations Research (OR) optimization problem of significant industrial importance. It is one of those problems where domain expertise does not help very much: whatever the number of years spent solving it, one is each time facing an intractable problem with an astronomic number of possible solutions and no real guidance on how to solve it in the best way, unless one postulates that the old way is the best way .Here we explain an apparent paradox: although many algorithms have been proposed in the past, and despite the problem’s practical importance, just one commercially available LB software currently appears to be available for application in industries such as automotive. We speculate that this may be due to a misalignment between the academic LB problem addressed by OR, and the actual problem faced by the industry. Keyword:Line Balancing, Assembly lines, Optimization
2019年车辆工程专业毕业论文_外文翻译1.doc
Drive force control of a parallel-series hybrid system Abstract Since each component of a hybrid system has its own limit of performance, the vehicle power depends on the weakest component. So it is necessary to design the balance of the components. The vehicle must be controlled to operate within the performance range of all the components. We designed the specifications of each component backward from the required drive force. In this paper we describe a control method for the motor torque to avoid damage to the battery, when the battery is at a low state of charge. Society of Automotive Engineers of Japan, Inc. and Elsevier Science B.V. All rights reserved. 1. Introduction In recent years, vehicles with internal combustion engines have increasingly played an important role as a means of transportation, and are contributing much to the development of society. However, vehicle emissions contribute to air pollution and possibly even global warming, which require effective countermeasures. Various developments are being made to reduce these emissions, but no further large improvements can be expected from merely improving the current engines and transmissions. Thus, great expectations are being placed on the development of electric, hybrid and natural gas-driven vehicles. Judging from currently applicable technologies, and the currently installed infrastructure of gasoline stations, inspection and service facilities, the hybrid vehicle, driven by the combination of gasoline engine and electric motor, is considered to be one of the most realistic solutions. Generally speaking, hybrid systems are classified as series or parallel systems. At Toyota, we have developed the Toyota Hybrid System (hereinafter referred to as the THS) by combining the advantages of both systems. In this sense the THS could be classified as a parallel-series type of system. Since the THS constantly optimizes engine operation, emissions are cleaner and better fuel economy can be achieved. During braking, Kinetic energy is recovered by the motor, thereby reducing fuel consumption and subsequent CO 2 emissions. Emissions and fuel economy are greatly improved by using the THS for the power train system. However, the THS incorporates engine, motor, battery and other components, each of which has its own particular capability. In other words, the driving force must be generated within the limits of each respective component. In particular, since the battery output varies greatly depending on its level of charge, the driving force has to be controlled with this in mind. This report clarifies the performance required of the respective THS components based on the driving force necessary for a vehicle. The method of controlling the driving force, both when the battery has high and low charge, is also described. 2. Toyota hybrid system (THS) [1,2] As Fig. 1 shows, the THS is made up of a hybrid transmission, engine and battery. 2.1. Hybrid transmission The transmission consists of motor, generator, power split device and reduction gear. The power split device is a planetary gear. Sun gear, ring gear and planetary carrier are directly connected to generator, motor and engine, respectively. The ring gear is also connected to the reduction gear. Thus, engine power is split into the generator and the driving wheels. With this type of mechanism, the