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
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
第三部分：词汇与结构（2016年4月统考）翻译版 1.55个标成红色的题目,重点复习,得分值6分 2.次重点41个为除红色外4月出现频率较高的题目,分值为4分,重点掌握 内部资料请勿传播，复习本资料无需看其他额外资料，词汇结构虽然功在平时，但临考前的准备也必不可少，本部分考5题共10分，基础较差的先重点温习标注红色的55题。 -------- 以下红色1-55 需重点掌握，得分值6分，每5小题后面KEY为答案-------- 1．It was well known that Thomas Edison the electric lamp. 众所周知，托马斯.爱迪生发明了电灯。 A．discovered B．invented C．found D．developed 2．The top of the Great Wall is for five horses to go side by side. 长城上面宽到足以能让五匹马并行。 A．wide B．so wide C．wide enough D．enough wide 3．Measles a long time to get over. 麻疹需要很长一段时间才能治好. A．spend B．spends C．take D．takes 4．-Do you want to wait? 您愿意等吗？ -Five days too long for me to wait. 五天等待的时间对于我来说太长了。 A. was B．were C．is D．are 5．There a book and some magazines on the desk.桌子上有一本书和一些杂志。 A．is B．are C．have D．has KEY:BADCA 补充：I don’t know ___B___ to deal with such matter.我不知道如何处理这类问题。A. what B. how C. which D. / 6．This kind of material expands the temperature increasing. 这种材料随温度的升高而膨胀。 A．to B．for C．with D．at 7．People at the party worried about him because no one was aware he had gone.晚会上的人都为他担忧，因为没人知道他去哪儿了。 A．of where B．of the place where C．where D．the place 8．A sudden noise of a fire-engine made him to the door. 火警突然响起使他匆忙走到门口。 A．hurrying B．hurried C．hurry D．to hurry 9．No matter , the little sisters managed to round the sheep up and drive them back home safely. 不管雪下的多大，两个小姐妹还是安全地把养拢起来赶回了家。 A．it was snowing hard B．hard it was snowing C．how it was snowing hard D．how hard it was snowing 10．There’s lots of fruit the tree. Our little cat is also in the tree.树上长了许多果实，我们的小猫也在上面。 A．in B．at C．under D．On
unit1 body 车身chassis 底盘enclosure外壳、套hood车棚、车顶sway 摇摆frame车架steering转向、操作brake 制动weld焊接rivet铆钉bolt螺钉washer垫圈vibration 振动stabilizer稳定器ride乘坐舒适性handling操作稳定性linkages转向传动机构plier钳子distributor分电器alternator交流发电机regulator调节器carburetor化油器radiator散热器、水箱defroster除冰装置sludge金属碎屑transmission变速器differential 差速器power train 传动系unitized body 承载式车身suspension system 悬架系统steering system 转向系braking system 制动系shock absorbers减震器control arms控制臂steering wheel 转向盘steering column转向管柱steering gears 转向器tie rod 横拉杆idler arm随动臂brake shoe制动蹄disc brake 盘式制动器drum brakes 鼓式制动器ignition system 点火系统exhaust system 排气系统lubrication system 润滑系oil filters 机油滤清器drive（or propeller）shaft传动轴universal joints 万向节dynamo发电机horn喇叭swived 旋转steering box转向器timing gear 正时齿轮bevel gear 锥齿轮mesh with与啮合leaf spring 钢板弹簧stub axle 转向节 unit2 longitudinal纵向的transverse横向的reciprocate往复spin旋转piston活塞ignite点火rub摩擦quart夸脱reservoir油箱mechanical机械的enclosed被附上的gallon加仑stroke冲程camshaft凸轮轴combustion燃烧disengaged脱离啮合的flywheel飞轮internal-combustion engine内燃机diesel-fuel柴油LPG=Liquefied Petroleum Gas液化石油气体CNG=Compressed natural gas压缩天然气spark ignition火花点火compression ignition压缩点火spark plug火花塞gas-turbine engine蒸汽机Stirling engine斯特灵发动机lubricating system润滑系统oil pan油底壳oil pump机油泵exhaust system排气系统emission-control system排放控制系统energy conversion能量转换air/fuel ratio空燃比connecting rod连杆TDC=Top Dead Center上止点BDC=Bottom Dead Center 下止点intake stroke进气冲程compression stroke压缩冲程power stroke作功冲程exhaust stroke排气冲程compression ratio压缩比lifter挺柱rocker摇臂retainer弹簧座seal密封件tappet 推杆lobe凸起gasket垫圈valve train配气机构cam follower气门挺柱rocker arm摇臂combustion chamber燃烧室intake valve进气阀exhaust valve排气阀valve stem气门杆valve cover气门室盖valve port阀口valve guide气门导管 unit3
英语新词汇与常用词汇的翻译-N篇 2010年9月 N.Y. 纽约 nab 逮捕 nabe 电影院 nabi 伊斯兰教先知 nabob 印度长官 nabobery 财主去处 nabobess 女财主 nabobism 巨富 Naboth 拿伯 Naboth's vineyard 为别人所垂涎之物 nabs 家伙 nacarat 桔红色 nacelle 引擎机舱 nacre 珠母贝 nacred 真珠质的 nacreous 真珠质的 Naderism 纳德运动 nadir 最低点 nae 不的 naevi 痣 naevus 痔 nag at 唠叨 nag 敦促 nag 老马 nagana 那加那病 nagger 爱唠叨 nagging 唠叨的 naggish 爱唠叨的 nagual 守护神 Nahum 那鸿 naiad 水中仙女 naif 像孩子的 nail a lie to the counter 拆穿西洋镜 nail clippers 指甲钳 nail down to 束缚 nail down 用钉钉住 nail file 指甲锉 nail one's colors to the mast 明确且坚持自己的要求 nail polish 指甲油 nail puller 起钉钳 nail scissors 修甲小剪刀 nail up 钉牢
nail 指甲 nail-biting 束手无策 nail-clippers 指甲刀nailbrush 指甲刷 nailer 敲打工人 nailery 制钉工厂nailhead 钉头 nailhole 钉眼 nailing 敲钉的 nailless 没有指甲的naillike 像指甲的 nailsick 不结实的nainsook 薄棉织物 naira 奈拉 Nairobi 奈洛比naissance 诞生 naive 天真的 naively 天真烂漫地naivete 纯真 naivety 天真烂漫 naked call 无担保承购期权naked eye 肉眼 naked 裸体的 nakedize 成为裸体nakedly 赤裸裸nakedness 裸 naker 定音鼓 Nakhodka 不冻港 naled 二溴磷 namable 可定名的namaste 合十礼namaycush 湖红点鲑namby-pamby 感伤的name after 按...命名name brand 名牌 name it 讲出来 name plate 名牌 name sb for 把...命名为name 名字 name-calling 骂人 name-child 起名 name-drop 抬高身价name-dropping 提高身份nameable 可命名的
汽车专业英语 主编：李崑 课后专业词汇汇总（带音标） 汇总：徐艳民 1 automobile ['?:t?m?ubi:l, ,?:t?m?'bi:l]汽车（美） assembly line [?'sembli]装配线 petroleum refining [pi'tr?uli?m, p?-]石油提炼 body and frame车身与车架 engine ['end?in] 发动机、引擎 drive line 传动系统 running gear 控制装置 suspension[s?'spen??n]悬架系统 unitized body ['ju:nitaizd]整体式车身 gasoline engine ['ɡ?s?li:n]汽油机 diesel engine ['di:z?l]柴油机 gas turbine['t?:bain, -bin]燃气轮机 battery ['b?t?ri]电池、电池组 fuel cell燃料电池 hybrid power ['haibrid][pau?]混合动力系统 piston ['pist?n]活塞 rotary engine ['r?ut?ri]转子发动机 vehicle ['vi:ikl, 有时发'vi:hi-]交通工具、车辆 transmission [tr?nz'mi??n, tr?ns-, trɑ:n-]变速器 drive shaft传动轴 differential [,dif?'ren??l]差速器 rear axle ['?ks?l]后轴、后桥 rear-wheel drive后轮驱动 front-wheel drive 前轮驱动 braking system 制动系统 wheel车轮 tire 轮胎 steering system 转向系统 spring [sp ri?]弹簧 shock absorber [??k] [?b's?:b?]减震器 Macpherson strut [m?k'f?:sn] [str?t]麦弗逊式悬架 torsion bar ['t?:??n]扭力杆 strut rod 支撑杆 stabilizer bar ['steibilaiz?]横向稳定杆 2 internal combustion engine [in't?:n?l] [k?m'b?st??n] ['end?in]内燃机 fuel 燃料 external combustion engine [ik'st?:n?l]外燃机 steam engine 蒸汽机 intermittent combustion engine[,int?'mit?nt]间隔燃烧式发动机 continuous combustion engine [k?n'tinju?s]连续燃烧式发动机 turbine engine ['t?:bain, -bin]涡轮发动机 rocket engine ['r?kit]火箭发动机 jet (or reaction) engine喷气式发动机 Wankel engine汪克尔发动机、转子发动机 stroke [str?uk]冲程、行程 cooling system冷却系统 fuel system燃料系统 ignition system [iɡ'ni??n]点火系统 spark-ignition engine 火花点燃式发动机 compression-ignition engine 压燃式发动机 liquid-cooled 用液体冷却的、水冷的 air-cooled 用空气冷却的、风冷的 3 cylinder block 气缸体 cylinder ['silind?]气缸 connecting rod 连杆 crankshaft['kr??k,?ɑ:ft]曲轴 cylinder head气缸盖 combustion chamber[k?m'b?st??n] ['t?eimb?]燃烧室 valve气门、阀 camshaft['k?m?ɑ:ft]凸轮轴 flywheel ['flaiwi:l]飞轮 intake manifold 进气歧管 exhaust manifold ['m?nif?uld]排气歧管 carburetor [,kɑ:bju'ret?, 'kɑ:-]化油器 fuel injector 燃料喷射器 cast iron ['ai?n]铸铁 aluminum [?'lju:min?m]铝 cooling fluid 冷却液 spark plug [pl?ɡ]火花塞 intake valve进气门 exhaust valve[iɡ'z?:st]排气门 cam凸轮 gear齿轮 belt皮带 chain链条 overhead camshaft (OHC) 凸轮轴上置式 rpm=revolutions per minute[,rev?'lju:??n]转速、转数/分钟 horsepower ['h?:s,pau?]马力、功率 intake system 进气系统 sensor ['sens?, -s?:]传感器 oxygen sensor ['?ksid??n]氧传感器 fuel induction system[in'd?k??n]燃料吸入系统 4 fuel tank 燃料箱、油箱 fuel line燃料管路 fuel pump 燃料泵、燃油泵 fuel filter [filt?]燃料滤清器 PCM (power train control module) 动力系统控制模块（计算机）
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.
最新英语专业全英原创毕业论文，都是近期写作 1 论《了不起的盖茨比》中的道德观 2 中国与日本茶文化的比较 3 网络英语的构词方式 4 翻译中的文化差异 5 从美国梦看美国社会流动机制 6 探析《老人与海》的主题 7 Roger Chillingworth in The Scarlet Letter Viewed from the Humanistic Perspective 8 赫尔曼?梅尔维尔《白鲸》中的生态主义解析 9 An Analysis of The Bible’s Influence on British and American Literature 10 计算机辅助教学在英语教学中的作用 11 An Analysis of Main Characters in Wuthering Heights 12 论《英国病人》中角色的自我认知 13 个体取向与集体取向对中美商务交流的影响 14 汉英姓氏文化差异 15 探析王尔德童话中的死亡主题 16 运用概念整合理论解读英语幽默理解障碍 17 初中生英语听力理解的障碍因素及对策 18 19 《等待野蛮人》中的寓言式写作手法 20 On Wisdom of Tao in Tao De Jing and the Subjectivity of Translator－－Based upon Translations of Wu（无）and You（有） 21 An Analysis of Translation of Road and Traffic Public Signs 22 象征主义视角下《致海伦》中的意象美 23 A Brief Analysis of Willy Loman’s Tragedy in Death of a Salesman 24 中式英语成因之分析 25 The Use of Symbols in A Farewell to Arms 26 管窥世纪年代以前的朴素社会语言学思想 27 论汉语新词语的英译 28 丁尼生《鹰》与休斯《鹰之栖息》的对比分析 29 A Study on English and Chinese Euphemisms from the Perspective of Cultural Difference 30 寻找真正的自我 31 浅析库尔特?冯尼古特《猫的摇篮》中的黑色幽默 32 广告英语的语言特征 33 On Translation of Symbolism in Pop Songs with a Case Study of Hotel California 34 霍桑的罪恶观在《红字》中的体现 35 面部表情和目视行为的跨文化研究 36 探析《劝导》中安妮的成熟形象 37 工业化进程下人的主体性的追问——梭罗的《瓦尔登湖》 38 论《荆棘鸟》中的女性意识 39 从《红字》看霍桑对清教主义的批判与妥协 40 A Contrastive Study on Language Features of Chinese and English Proverbs
汽车专业英语复习题 名词翻译： 1、活塞环 piston ring 2、电控系统electronic control system 3、里程表speedometer 4、发动机排量engine capacity 5、自动变速器automatic transmission 6、机油表oil gauge 7、方向盘steering wheel 8、做功冲程power stroke 9、exhaust gas废气 10. electric current电流 11. high gear高速档 12. automobile dealing汽车贸易 13. sports car 跑车 14. instrument panel仪表板 15. accelerator pedal加速踏板 16. physical property 物理性能 17、电子燃油计量系统electronic fuel metering system 18、减速slow down 19、刹车蹄brake shoe 20、General Motor 通用 21、wheel drum 车轮毂 22、TDC 上止点 23、BDC 下止点 翻译（中译英）： 上海汽车工业总公司已与德国大众和美国通用两大汽车公司建立了合资公司。 The Shanghai Auto Industry Corportion has established joint ventures with German V olkswagen and American General Motors. 四冲程发动机—曲柄旋转两圈做功一次。 Four stroke —a power stroke every other revolution of the crank. 液体冷却系由水泵、水套、发动机风扇、散热器等组成。 The liquid cooling system consists of water pumps，water jackets，engine fan ，radiator and so on. 在仪表板上，我们能看见几个显示发动机运转情况的仪表。
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（6）Maintain correct viscosity (free flowing at all temperatures). 保持正确的粘度（在所有温度下自由流动）。 When the brake fluid boils, it becomes vapor. A vapor can be compressed, but a liquid cannot be compressed. Pressing on the brake pedal will compress the vapor in the lines instead of transferring the pressure through the fluid. This can lead to partial or complete braking system failure, sometimes called brake pedal fade. Mountain driving puts increased duty on brakes and brake fluid. The boiling point drops at high altitude. This naturally increases the tendency towards vapor lock. In fact, vapor lock in the hydraulic braking system is the primary reason for brake pedal fade. 当制动液沸腾时，它变成蒸汽。可以压缩蒸汽，但不能压缩液体。按压制动踏板将压缩管线中的蒸汽，而不是将压力传递通过流体。这可能导致部分或完全制动系统故障，有时称为制动踏板褪色。山地驾驶增加了刹车和制动液的使用。沸点在高海拔下降。这自然增加了气体锁定的趋势。事实上，液压制动系统中的汽油锁是制动踏板褪色的主要原因。 Vehicle manufacturers recommend brake fluid that meets or exceeds SAE (Societyof Automotive Engineers)andDOT (Department of Transportation) specifications. 车辆制造商推荐符合或超过SAE（汽车工程师协会）和DOT（运输部）规格的制动液。 Standard brake fluid (DOT 3) is composed chiefly of equal parts of alcohol and castor oil. This combination of fluids works well under normal conditions but it easily boils and becomes a vapor under heavy-duty applications. It also tends to separate when exposed to low temperatures. 标准制动液（DOT 3）主要由酒精和蓖麻油组成。这种流体组合在正常条件下工作良好，但在重载应用下容易沸腾并成为蒸气。暴露于低温时也容易分离。The increasing requirements of brake fluid led to the development of silicone brake fluid,such as DOT 5. This fluid achieved low water pickup and good corrosion protection and also provides good lubrication qualities and rubber compatibility. 制动液的要求越来越高，导致了DOT 5等硅胶制动液的开发。该液体实现了低吸水率和良好的防腐蚀性能，并且还具有良好的润滑性能和橡胶相容性。 5.Brake valves 5.闸阀 There are typically five types of valves in vehicle braking system to adjust the braking force distribution. 车辆制动系统中通常有五种类型的阀门来调节制动力分布。 (1)Metering valve （1）计量阀 Most vehicles that have front disc and rear drum brakes are equipped with metering valve. This metering valve controls, or delays the flow of brake fluid to the front brakes. The rear drum brakes take longer to respond than the front disc brakes. The valve ensures that front disc brake do not act before the rear drum brake. The delays is long enough to allow the rear drum brakes time to react. This delay is particularly necessary during light braking and on slick road surfaces.