现在的车辆一般都由15000多个分散、独立且相互配合的零部件组成。这些零部件主要分为四类：车身、发动机、底盘和电气系统。
汽车车身是一个包含窗子、车门、一个发动机罩、一个行李箱盖的金属薄壳。汽车车身为发动机、乘员和货物提供了保护。
汽车车身的设计还应该保证乘员的安全舒适。车身的造型（款式）使得汽车看起来漂亮迷人、色彩斑斓、时尚前卫。
轿车车身为封闭式，轿车最多有4个车门，乘员通过车门进出。另外车身的设计还应考虑行李和货物的存放。传统的轿车都是硬顶车身。活顶乘用车（敞篷车）的车顶是软顶，车身设计与普通轿车类似，但只有两个车门。
皮卡一般用来运载货物。为能承载更大的总质量，皮卡的底盘部件和悬架比轿车更结实。轻型货车一般是基于普通轿车设计的，或是重新设计使可用载货空间最大化。
用于运输货物的商用车车身必须满足具体要求，例如运输液体的油罐车、运输泥土或散装谷物的自卸车、运输一般货物的平板车或货车。
发动机作为动力设备，常见的类型是内燃机，其原理是通过发动机缸内的液体燃料燃烧而产生能量。发动机可分为两类：汽油机（点燃式）和柴油机（压燃式），都属于热力发动机。燃料燃烧产生热量使缸内气体气压上升，从而产生能量，驱动与动力传动系相连接的轴旋转。
发动机的布置即发动机气缸的排列方式。发动机缸体按直线排列的即直列式，这种布置使得发动机缸体结构简单。汽车发动机一般为2~6缸，通常气缸是垂直放置的，但气缸数量的增加会导致缸体和曲轴的长度过大，解决问题的措施之一就是采用V型布置，这种布置方式可以使发动机缸体和曲轴长度尺寸更短，从而大大增加刚度。
前置发动机可以纵向布置，能够驱动前轮或后轮。后置发动机布置在后轮后侧，发动机即可纵向布置又可横向布置，一般只能驱动后轮。
底盘总成是由作为汽车主要运行部分的各系统组成，包括动力传动系、转向系统、悬架和制动系统。
传动系把发动机输出的扭矩传递给驱动轮。传动系包括离合器（对应机械变速器）或液力变矩器（对应液力自动变速器）、变速器、驱动轴、主减速器、差速器和驱动桥。另外有些传动系采用由变速器、主减速器和差速器组成的一体式的变速驱动桥。（或者采用一个独立的变速驱动桥，即变速器……在同一个箱体内。）
对于采用机械变速器的汽车，其发动机扭矩由离合器传递给变速器或变速驱动桥，并通过离合器来控制发动机和传动系的啮合或分离。变速器包含了不同传动比的齿轮副，能够增加或减小扭矩。选择的齿轮速比越小，传递的扭矩最大。汽车起步时需要较大的扭矩，一旦起动后，仅需要较小的扭矩就可维持速度，此时应该换用较高的档位，以降低发动机转速。
传统的汽车采用前置发动机、后轮驱动，因此需要传动轴把动力从变速器传递给主减速器。
主减速器的作用就是在把动力传递给驱动轮之前，降低转速并增加扭矩。对于前置后驱的汽车，主减速器还将驱动的旋转方向改变了90度。主减速器内的差速器齿轮副，把动力分给两个驱动轴，并允许两边车轮在转向时具有不同的转速。动力最终由驱动轴传递给车轮。后轮驱动汽车的驱动桥应能满足悬架的运动，可以是刚性的或包含运动副。为满足悬架和转向的要求，前轮驱动汽车驱动轴上需安装万向节。
自动变速器或自动变速驱动桥的功能和机械式基本类似，区别在于档位的选择是液力或电力控制的。液力自动变速器采用液力变矩（耦合）器作为连接器以传递动力。
整个悬架系统的作用是隔离来自路面的冲击和振动对车身的影响，防止传递给乘员和货物。
另外不论路面如何，悬架系统都应该保持轮胎和路面接触。悬架系统的基本组成包括弹性元件、车桥、减震器、杆系（臂、杆）和球副组成的导向机构。
弹簧是悬架的弹性元件，常见的弹簧类型有：钢板弹簧、螺旋弹簧和扭杆弹簧。现代汽车大多采用小的螺旋弹簧，轻型商用车常采用的螺旋弹簧比一般乘用车的大得多，或者前悬架采用螺旋弹簧，后悬架采用钢板弹簧。重型商用车则通常采用钢板弹簧或空气弹簧。
车轮必须能支撑整车重量，并能承受正常工况下的载荷。同时车轮必须尽可能地轻，有助于最小化簧下质量。
车轮可采用双面钢化板压制而成，也可采用铸造的铝合金材料。除了外观漂亮之外，铝合金比钢更轻，因此铝合金车轮应用较广。另外铝合金导热性更好，因此相比钢制车轮，制动器和车轮产生的热量更容易被铝合金车轮散发。
轮胎在汽车和路面之间起缓冲作用，能减小路面冲击。同时轮胎也提供了车轮正常行驶所需的摩擦力。轮胎是由多种材料加工而成，橡胶多是人工合成的。最常见的轮胎类型是子午线轮胎和斜交轮胎。现在大部分乘用车都采用子午线轮胎，在四轮驱动和商用车上，子午线轮胎也正在取代斜交胎。
有内胎的轮胎用内胎来密封内部气体。无内胎的轮胎则要求车轮和轮胎具有很好的密封性，这就需要专用的密封件，可以紧固在轮缘上，也可用螺钉和密封圈来固定。
鼓式制动器的制动鼓和轮毂连接，制动蹄张开压紧制动鼓内侧从而产生制动。在盘式制动器上，连着轮毂的制动盘被紧紧夹在两个制动块之间。轻型汽车上都采用液压制动系统，制动踏板控制制动主缸，通过液压管路与车轮上的制动轮缸相连。现在轻型汽车上的制动器，前轮采用盘式，后轮采用鼓式，或全部采用盘式。相比鼓式制动器，盘式制动器需要更大的作用力。在制动时采用增压器辅助驾驶员提高施加在主缸上的制动力。
重型商用车多采用气压制动系统，压缩气体作用在直径较大的膜片上时能为制动总成提供较大的制动力。气压制动系统靠空气压缩机把气体吸入储气罐。驾驶员控制阀门开启，使压缩气体进入车轮制动气室进行制动。在铰接车辆的拖车上采用继动阀和单独的储气罐，以减小拖车制动系统的时间延迟，这种布置方式还可以在拖车失去动力时制动拖车。
所有汽车必须安装至少两套独立的制动系统，即行车制动系统与紧急制动系统，一般被称之为脚制动和停车制动。大部分轻型汽车的脚制动通过液压系统作用在四个车轮上，而其手制动则是机械式的，且仅作用在后轮。手制动的一个普通用途就是停车时对汽车进行制动。设计两套独立的制动系统的目的就是当一套失效时，另一套仍可工作。
电器系统为起动机、点火系、照明和加热设备提供电流，电流的大小由充电电路来维持。
Charging
充电系统为汽车上所有的电器系统提供电能。充电系统主要组成部分有：蓄电池、交流发电机、稳压器（多集成在发电机中），充电指示灯和组成电路的电线。汽车起动时由蓄电池提供能量，一旦发动机开始工作，交流电机为电气设备供电，同时还对蓄电池进行充电，以补偿起动所消耗的电能。稳压器则防止过载。
Starting
起动系统包括电池、电缆、启动电机、飞轮齿圈和点火开工。起动需要两个动作，启动电机齿轮和飞轮齿圈啮合，从而带动发动机转动。起动电机安装在发动机壳体上，靠电池工作。
Ignition
点火系统包括电池、低压电缆、点火线圈、分电器、高压电缆、火花塞连线和火花塞。点火系统在火花塞处产生高压火花，点燃发动机燃烧室内的燃油混合物。点火系统必须在
恰当的时刻提供火花，并且能量满足各种工况的要求。电池和交流发电机为点火系统供电，点火线圈提高电压。点火系统由两级电路组成，初级电路（低压电路）初始化火花，次级电路（高压电路）产生高压电，并分到各个火花塞。
发动机缸体是发动机的基本骨架，发动机其余的零件或安装在缸体内部，或固定在缸体上。缸体里有气缸、水套和油道，曲轴也固定在缸体底部。除了顶置凸轮轴发动机以外，凸轮轴都固定在缸体内部。大多数汽车上，缸体采用灰铸铁或者灰铸铁和其他金属（例如镍或铬）的合金铸造而成。
发动机缸体中的气缸套为活塞和活塞环提供一种坚硬耐磨的材料。缸体可以采用较轻且易铸造的铁，而气缸套采用更耐磨和耐冲击的材料。气缸套分为两种：干式和湿式。
气缸盖固定在气缸体的顶部，就像房子的房顶一样。气缸盖底部与活塞头部之间的空间形成了燃烧室。轻型汽车的直列式发动机采用一个气缸盖，较大的直列式发动机采用两个或多个气缸盖。
润滑系的机油泵从油底壳抽出机油，并把机油输送给发动机的所有工作部件。机油从油底壳流进流出。因而在油底壳和发动机的工作部件之间就有机油定向循环流动。
大多数活塞由铝铸造而成。通过连杆的作用，活塞把可燃混合气燃烧产生的力传递给曲轴，带动曲轴旋转。
柴油机发动机根据喷油方法不同，活塞头部可以形成全部燃烧室，也可以是燃烧室的一部分．
连杆采用高强度锻造钢。连杆将活塞的力和运动传递给曲轴上的曲柄销。连杆小头与活塞销连接，连接处有像青铜这样软金属制成的衬套，连杆下端连接在曲柄轴径上，称为连杆大头。
凸轮是一个蛋形的金属块，它安装在同曲轴协调运转的一根金属轴上，该轴称为凸轮轴，其上有同发动机每一个气门对应的凸轮。当凸轮轴旋转时，凸轮的最高点，也就是凸圆，推动连接气门杆的部件，使得气门向下运动，在进气冲程打开进气门，在排气冲程打开排气门。
当发动机处于压缩行程或做功行程时，气门必须紧闭在气门座上，提供很好的密封性，从而防止气体从燃烧室中溢出。如果气门不能完全关闭，则发动机不能产生最大的功率。另外气门头容易被流经的高温气体烧蚀，有可能导致活塞头部冲击打开的气门，会严重破坏发动机。
从上述描述显而易见，排气门开启时，有一小段时间，进气门也是开启的。换句话说，排气行程终了和进气行程初期有一短时间的重叠，这就称之为气门重叠。不同的发动机具有不同的气门正时和气门重叠。
汽车的动力源是发动机。发动机乃是将某一种形式的能量转变为机械能的机器。将热能转变为机械能的发动机，称之为热力发动机，其中的热能是由燃料燃烧所产生的。内燃机是热力发动机的一种，其特点是液体或气体燃料和空气混合后直接输入机器内部燃烧而产生热能，然后再转变为机械能。
汽油必须容易蒸发，这个特性也叫挥发性，是十分重要的。但是汽油不能太容易蒸发，否则汽油会在油箱或油路中蒸发。燃油在油路中的蒸发会堵塞液体汽油的流通，称之为气阻。油泵的入口端暴露在高温下时，油路中常出现气阻。
当前大多数汽车采用机械汽油泵，汽油泵从油箱抽出汽油，通过油管送到化油器或喷射系统。大部分汽车的汽油泵安装在缸体上。一些汽车采用电动汽油泵，汽油泵安装在油箱上，附带有油量传感器和燃油表油量传送装置。
化油器传输的燃料和流经化油器的空气流量成一定比例。踏下加速踏板，节气门开度变大，化油器吸入的空气量增加。化油器可提供过浓或过稀的混合物，这取决于许多因素：发动机转速，负载，温度和节气门位置。为满足复杂的要求，化油器是高度复杂的装置，包含了许多内部管路和部件（图2.21）。
汽车化油器设计成带有喉管的形状。喉管只是空气通道中一段狭窄部分。流经化油器节气门的空气在通过这段狭窄通道时速度加快，在燃油喷嘴出行程了一个低压区。大气压力作用在化油器内部储存汽油的浮子室。燃油被压入通向喉管低压区的管道，这样，燃油从油管末端喷射到气流中。
当汽车原地起步时，离合器把静止的变速器轴同发动机接合起来，此时发动机必须高速旋转以提供足够大的功率，否则载荷过大将引起发动机熄火。
主动部分由飞轮和压盘两部件组成。飞轮用螺栓直接连接到发动机曲轴上，随曲轴旋转而旋转。压盘与飞轮连接，这样飞轮和压盘一起旋转。
从动盘的内部（毂缘）有一些叫作扭转弹簧的小螺旋弹簧，这些弹簧使得从动盘中部相对从动盘毂能有轻微转动，从而吸收曲轴的扭转振动。压紧弹簧完全压缩时，离合器回位直到弹簧开始松弛。也就是说，离合器吸收发动机的振动，防止振动传递给传动系。
大部分自动变速器采用液力耦合器连接发动机曲轴和变速器输入轴。液力耦合器和液力变矩器通过流动的液体的能量传递力矩。由于转速和力矩的转变是连续变化的，它们的优点是在起步时得到最大力矩。
对滑动啮合变速器来说，换挡时要避免噪声是需要技巧的。齿轮打齿是由换挡不当引起的，这也是滑动啮合变速器经常被称为“碰撞”型变速器的原因。
为实现快速、安静地换挡，驾驶员必须使用双脚离合器。这个动作补偿了即将啮合的齿轮圆周速度。
汽车从原地起步(静止)加速到某一速度需要能量，储存在汽车中的那部分能量称为动能。要降低车速,制动器必须把动能转换为热能；转换的速度决定了汽车减速的快慢就领从蹄而言，C*(制动因数)表示各蹄的总和，且≈２.０(特指某一摩擦系数）．这种设计的缺点是两个制动蹄的制动效果差别很大，结果大大增加了领蹄上的摩擦．因此，从蹄的摩擦衬片比领蹄薄．
在许多乘用车上使用的盘式制动器逐渐开始应用在商用车上。除快速客车外, 盘式制动器在商用车的使用基本限制在的前桥制动系, 且整车重量不超过7.5吨，这种商用车的驱动方式与乘用车相似。
分离式车架必须足够轻巧而且结实，以承受变化的载荷和路面作用力。商用车通常使用分离式钢质车架，以满足各种载荷对刚度的要求。两根槽形的长纵梁铆接着许多横梁，这使车架重量较轻，具有较好的抗弯和抗扭能力。
多数汽车采用整体式车身，即车身和车架组合在一起。整体式车身比车身/车架式结构质量轻，但噪声大。在车身部分和机械部件之间安装橡胶块以吸收振动。地板由一些支撑后悬架和变速器的部件组成。
第一章汽车总论 1)Today’s average car contains more than 15,000 separate, individual parts that must work together. These parts can be grouped into four major categories: body, engine, chassis and electrical equipment 。P1 现在的车辆一般都由15000多个分散、独立且相互配合的零部件组成。这些零部件主要分为四类：车身、发动机、底盘和电气设备。 2)The engine acts as the power unit. The internal combustion engine is most common: this obtains its power by burning a liquid fuel inside the engine cylinder. There are two types of engine: gasoline (also called a spark-ignition engine) and diesel (also called a compression-ignition engine). Both engines are called heat engines; the burning fuel generates heat which causes the gas inside the cylinder to increase its pressure and supply power to rotate a shaft connected to the power train. P3 发动机作为动力设备，常见的类型是内燃机，其原理是通过发动机缸内的液体燃料燃烧而产生能量。发动机可分为两类：汽油机（点燃式）和柴油机（压燃式），都属于热力发动机。燃料燃烧产生热量使缸内气压上升，产生的能量驱动轴旋转，并传递给动力传动系。 第二章内燃机 1)Power train system: conveys the drive to the wheels 2)Steering system: controls the direction of movement 3)Suspension system: absorbs the road shocks 4)Braking system: slows down the vehicle P4 传动系把发动机输出的扭矩传递给驱动轮。传动系包括离合器（对应机械变速器）或液力变矩器（对应液力自动变速器）、变速器、驱动轴、主减速器、差速器和驱动桥。 5)Drum brakes have a drum attached to the wheel hub, and braking occurs by means of brake shoes expanding against the inside of the drum. With disc brakes, a disc attached to the wheel hub is clenched between two brake pads. P6 鼓式制动器的制动鼓和轮毂连接，制动蹄张开压紧制动鼓内侧从而产生制动。在盘式制动器上，连着轮毂的制动盘被紧紧夹在两个制动块之间。 1)Linking the piston by a connecting rod to a crankshaft causes the gas to rotate the shaft through half a turn.The power stroke"uses up"the gas,so means must be provided to expel the burnt gas and recharge the cylinder with a fresh petrol-air mixture:this control of gas movement is the duty of the valves;An inlet valve allows the mixture to enter at the right time and an exhaust valve lets out the burnt gas after the gas has done its job . P10 活塞通过连杆和曲轴连接，使得气体带动曲轴旋转半圈。作功冲程耗尽了所有的气体，这样就必须采取相应的措施排出废气并且向气缸内充入新的可燃混合气：气体的运动由气门来控制。进气门使可燃混合气在恰当的时刻进入气缸，排气门使燃烧后的废气排出气缸。 2)The spark-ignition engine is an internal-combustion engine with externally supplied in ignition,which converts the energy cntained in the fuel to kinetic energy.The cycle of operations is spread over four piston strokes. To complete the full cycle it takes two revolutions of the crankshaft. P11 火花点火式发动机是由外部提供点火的内燃机，从而将含在燃料内的能量转化成动能。发动机的一个工作循环分布在活塞的四个行程中，一个完整的工作循环曲轴需要转动两圈。 3)The oil pump in the lubricating system draws oil from the oil pan and sends it to all working parts in the engine. The oil drains off and runs down into the pan. Thus,there is constant circulation of oil between the pan and the working parts of the engine. P15
哲学Philosophy 马克思主义哲学Philosophy of Marxism 中国哲学Chinese Philosophy 外国哲学Foreign Philosophies 逻辑学Logic 伦理学Ethics 美学Aesthetics 宗教学Science of Religion 科学技术哲学Philosophy of Science and Technology 经济学Economics 理论经济学Theoretical Economics 政治经济学Political Economy 经济思想史History of Economic Thought 经济史History of Economic 西方经济学Western Economics 世界经济World Economics 人口、资源与环境经济学Population, Resources and Environmental Economics 应用经济学Applied Economics 国民经济学National Economics 区域经济学Regional Economics 财政学（含税收学）Public Finance (including Taxation) 金融学（含保险学）Finance (including Insurance) 产业经济学Industrial Economics 国际贸易学International Trade 劳动经济学Labor Economics 统计学Statistics 数量经济学Quantitative Economics 中文学科、专业名称英文学科、专业名称 国防经济学National Defense Economics 法学Law 法学Science of Law 法学理论Jurisprudence 法律史Legal History 宪法学与行政法学Constitutional Law and Administrative Law 刑法学Criminal Jurisprudence 民商法学(含劳动法学、社会保障法学) Civil Law and Commercial Law (including Science of Labour Law and Science of Social Security Law ) 诉讼法学Science of Procedure Laws
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,
Unit1 发动机是汽车的心脏。汽车引擎的目的是将燃料转化为能量使汽车移动。最简单的方法是在发动机内部燃烧燃料。,因此,汽车发动机是一种内燃机,缸内燃烧燃料和燃烧的扩张力量转换成旋转力用来驱动汽车。 这里有多种类型的内燃机分为往复式和旋转式引擎;火花式点火或压缩式点火发动机;代用燃料发动机。 往复式发动机 最熟悉的组合是往复式,火花点火,四冲程汽油发动机,如图1-1a所示。现代汽车通常是由水冷活塞式内燃机,安装在汽车的前面,它的力量可以被传送到前轮，传到后轮,或所有车轮轮。一些汽车使用风冷式发动机,但这些通常效率不及液冷式。往复式发动机的另一个主要类型是柴油发动机(如图果1-1b所示),这是使用重型车辆，如卡车，公共汽车和少数家庭轿车。柴油和汽油发动机一般采用四冲程循环。 转子式发动机 转子式内发动机,也叫汪克尔发动机,由德国的Felix~Wankel在1954年开发的,可以提供一种低废气排放和大规模生产的可行性的发动机来替代往复式发动机机。在这种发动机中，三面转子在燃烧室的自由空间内旋转使其随着转子转动压缩和膨胀,见图1 - 2。燃料被吸入、压缩和被点火系统的点燃。膨胀的气体带动转子然后废气排出,如图1 - 3所示。旋转式引擎没有气门,活塞,连杆,往复部件,或曲轴。它提高了马力,基本上不会有震动,但它的油耗是高于传统活塞式发动机。 代用燃料汽车 内燃机消耗大量的石油,并造成严重的空气污染,因此,其他类型的燃料和非常规引擎被研究和发展。 可替代燃料汽车(AFV)是一种用常见的油箱的柔性燃料车辆，设计一种在不同混合的无铅汽油与乙醇或双燃料汽车运行，一种可使用替代燃料和传统燃料。一种高科技车辆(A TV)结合了新引擎,动力传动机构,传动系系统显著提高燃油经济性。最理想的替代燃料发动机燃烧燃料比传统汽油内燃机更为简洁,但仍然能够使用现有的加油站。 混合动力电动车 混合动力汽车或者混合电动汽车(HEV)(如图1 - 4所示),是由两个或两个以上的能源,其中之一是电力可以高英里每加仑，低排放。有两种类型的混合动力汽车,串联和并联式。在串联式电动汽车中,车辆动力所有动力来自同一个源头。例如,一个电动马达驱动的汽车电池和内燃机驱动发电机给电池充电。在并联混合动力,电力是通过这两个路径,电动机和内燃机驱动车辆。这一点,可能有助于电力汽车的电动发动机空转和加速度。内燃机巡航时,驱动传动系和给电池充电。 在当前生产混合动力车发动机和电动马达连接,同样的传播协助下电动引擎可以更小。
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.
About car engine Of all automobile components,an automobile engie is the most complicated assembly with dominant effects on the function of an autombile.So, the engine is generally called the"heat"of an automobile. 在汽车的所有部件中，汽车发动机是最复杂的组件，其对整车性能有着决定性的作用。因而发动机往往被称作发动机的“心脏”。 There are actually various types of engines such as electric motors,stream engines,andinternal combustion engines.The internal combustion engines seem to have almost complete dominance of the automotive field.The internal combustion engine,as its name indicates,burns fuel within the cylinders and converts the expanding force of the combustion into rotary force used to propel the vehicle. 事实上，按动力来源分发动机有很多种，如电动机、蒸汽机、外燃机等。然而内燃机似乎在发动机领域有着绝对的统治地位。就像其字面意思一样，内燃机的染料在气缸内燃烧，通过将燃烧产生气体的膨胀力转换成转动力来驱动发动机前进。 Engine is the power source of the automobile.Power is produced by the linear motion of a piston in a cylinder.However,this linear motion must be changed into rotary motion to turn the wheels of cars or trucks.The puston attached to the top of a connecting rod by a pin,called a piston pin or wrist pin.The bottom of the connecting rod is attached to the crankshaft.The connecting rod transmits the up-and-down motion of the piston to the crankshaft,which changes it into rotary motion.The connecting rod is mounted on the crankshaft with large bearings called rod bearing.Similar bearings, called main bearings,are used to mount the crankshaft in the block. 发动机是整部车的动力来源。能量来自于活塞在气缸内的（往复）直线运动。然而这种（往复）直线运动必须要转换成旋转运动才能驱动车轮。活塞与连杆通过一个销来连接，这个销称为活塞销。连杆的下部连接于曲拐。连杆把活塞的上下往复运动传递给曲拐，从而将往复直线运动转变成旋转运动。连杆和曲拐的连接使用大的轴承，称之为连杆轴承，类似的轴承也用于将曲轴连接到机体，称之为主轴承。 They are generally two different types of cooling system:water-cooling system and air-cooling system.Water-cooling system is more common.The cooling medium, or coolant, in them is either water or some low-freezing liquid, called antifreeze.A water-cooling system consists of the engine water jacket, thermostat, water pump, radiator, radiator cap, fan, fan drive belt and neccessary hoses. 主要有两种类型的冷却系统：水冷和风冷。水冷系统更为普遍。系统所用冷却介质或是冷却液常委水或其他低凝固点液体，称为抗凝剂。一个完整的水冷系统包括机体水套，节温器，水泵，散热器，散热器罩，风扇，风扇驱动皮带和必需的水管。 A water-cooling system means that water is used as a cooling agent to circulate through the engine to absorb the heat and carry it to the radiator for disposal.The ebgine is cooled mainly through heat transfer and heat dissipation.The heat generated by the mixture burned in the engine must be transferred from the iron or aluminum cylinder to the waterin the water jacket.The outside of the water jacket dissipates some of the heat to the air surrounding it, but most of the heat is carried by the cooling water to the radiator for dissipation.When the coolant temperature in the system reaches 90°,the termostat valve open fully, its slanted edge shutting off
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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
INTERNAL COMBUSTION ENGINE 引擎燃烧室 1. principle of operation 原理 Engine and power : Engine is used to produce power. The chemical energy in fuel is converted to heat by the burning of the fuel at a controlled rate. This process is called combustion. If engine combustion occurs with the power chamber. ,the engine is called internal combustion engine. If combustion takes place outside the cylinder, the engine is called an external combustion engine. Engine used in automobiles are internal combustion heat engines. Heat energy released in the combustion chamber raises the temperature of the combustion gases with the chamber. The increase in gas temperature causes the pressure of the gases to increase. The pressure developed within the combustion chamber is applied to the head of a piston to produce a usable mechanical force, which is then converted into useful mechanical power. 译: 引擎和能量: 引擎为汽车提供能量，燃料的化学能通过燃烧，转化为热能，这个过程叫燃烧。假如燃烧在燃烧室，这样的发动机叫内燃机。假如燃烧在气缸外，这样的发动机叫外燃机。 用在汽车上的一般是内燃机，热能在燃烧室释放，燃烧室气体温度升高。气体温度的升高使气体的压力曾加，燃烧室内的高压气体作用在活塞头部产生可以利用的化学能，化学能转化为机械能。 Engine T erms : Linking the piston by a connecting rod to a crankshaft causes the gas to rotate the shaft through half a turn. The power stroke “uses up” the gas , so means must be provided to expel the burnt gas and recharge the cylinder with a fresh petrol-air mixture :this control of gas movement is the duty of the valves ;an inlet valve allows the new mixture to enter at the right time and an exhaust valve lets out the burnt gas after the gas has done its job. Engine terms are : TDC(Top Dead Center):the position of the crank and piston when the piston is farther away from the crankshaft. BDC(Bottom Dead Center):the position of the crank and piston when the piston is nearest to the crankshaft. Stroke : the distance between BDC and TDC; stroke is controlled by the crankshaft. Bore : the internal diameter of the cylinder. Swept volume : the volume between TDC and BDC Engine capacity : this is the swept volume of all the cylinder e.g. a four-stroke having a capacity of two liters(2000cm) has a cylinder swept volume of 50cm. Clearance volume: the volume of the space above the piston when it is at TDC. Compression ratio = (swept vol + clearance vol)\(clearance vol) Two-stroke : a power stroke every revolution of the crank.