车辆专业英语

1 2Engine 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 发动机作为动力装置 内燃机是最常见的 通过燃烧发动机气缸里的液体燃料 而获得能量 内燃机有两种类型 汽油机 又称为点燃式发动机 和柴油机 又称为压燃式发动机 两种类型均被称为热力发动机 燃烧燃料产生的热量 使汽缸里气体的气压增加并提供能量通过传动轴连接到传动系统 1 3 Body An automobile body is a sheet metal shell with windows doors a hood and a trunk deck built into it It provides a protective covering for the engine passengers and cargo The body is designed to keep passengers safe and comfortable The body styling provides an attractive colorful modern appearance for the vehicle 汽车车身是由车窗 车门 发动机罩和行李箱盖焊接在金属板外壳内而成 车身为发动机 乘客和货物覆盖提供保护 车身的设计要保证乘客安全舒适 车身的款 式为汽车提供了吸引人的 美丽多彩的 时尚的外观 2 1 1 Engine and power 发动机与动力发动机与动力 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 能源是用于生产动力 燃料的化学能通过燃烧转化为热量 这个过程被称 为燃烧 如果发动机燃烧发生在汽缸内的地方 这个发动机被称为内部燃烧发 动机 如果燃烧发生在汽缸外的地方 被称为发动机外部燃烧发动机 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 用于汽车的发动机是内燃机 热能在燃烧室释放提高了燃烧室气体温度 燃烧气体温度的升高引起气压变大 燃烧室内压力增大被应用到了活塞产生一 个可用的机械力 然后将其转换成有用的机械能 2 1 2 Engine Terms 发动机术语发动机术语 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 通过曲轴连杆连接活塞 造成气体轴旋转半转 动力冲程 使用了 气压 意味 着必须提供手段驱逐燃烧气体和回灌用新鲜的汽油和空气混合气体钢瓶 这种 气体的运动控制是阀门的责任 一进气阀使新进入的混合物在适当的时间和一排 气阀让燃烧后的气体在已完成了它的工作任务后排出 2 1 4 Engine Overall Mechanics 发动机结构发动机结构 The engine has hundreds of other parts The major parts of engine are engine block engine heads pistons connecting rods crankshaft and valves The other parts are joined to make systems These systems are the fuel system intake system ignition system cooling system lubrication system 润滑 and exhaust system Each of these systems has a definite function These systems will discussed in detail later 后续章节 2 2 1Engine Block 发动机缸体发动机缸体 The engine block is the basic frame of the engine All other engine parts either fit inside it or fasten to it It holds the cylinders water jackets and oil galleries The engine block also holds the crankshaft which fastens to the bottom of the block The camshaft also fits inside the block except on overhead cam engines OHC In most cars this block is made of gray iron or an alloy mixture of gray iron and other metals such as nickel or chromium Engine blocks are castings 发动机缸体是发动机的基本框架 所有其他发动机零件要么在其中要么固定它 上面 它包含气缸 水套 油道 发动机缸体还装有曲轴 被固定在缸体底部 凸轮轴块通常装在缸体内 除顶置凸轮 OHC 发动机 在大多数汽车 这个部 件是由灰铸铁或者一种合金 混合物 灰铁和其它金属如镍或铬 发动机缸体 是铸件 Some engine blocks especially those in smaller cars are made of cast aluminum This metal is much lighter than iron However iron wears better than aluminum Therefore the cylinders in most aluminum engines are lined with iron or steel sleeves These sleeves are called cylinder sleeves Some engine blocks are made entirely of aluminum 有些气缸体 特别是在小汽车里的那些 都是由铝做成的 这种金属比铁轻得 多 然而 铁的耐磨性比铝好 因此 在大多数铝制发动机的气缸内镶有铁或 钢套管 这些轴套被称为气缸套 有些气缸体完全由铝做成 2 2 3 Gasket 衬垫衬垫 The cylinder head is attached to the block with high tensile steel studs The joint between the block and the head must be gas tight so that none of the burning mixture can escape This is achieved by using cylinder head gasket This is a sandwich gasket i e a sheet of asbestos between two sheets of copper both these materials being able to withstand the high temperature and pressures within the engine 气缸盖连接到具有高强度气缸体 它们之间的连接必须不透气 使燃烧的混合 气体不能泄露 这是通过使用气缸盖垫片实现 这是一个夹层垫片 即在两片 铜之间有石棉 这两种材料能承受发动机内高温和压力 2 2 4 Oil Pan or Sump 油底壳油底壳 The oil pan is usually formed of pressed steel The oil pan and the lower part of the cylinder block together are called the crankcase they enclose or encase the crankshaft 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 油底壳通常由钢冲压形成 油底壳和气缸体的下半部分一同被叫做曲轴箱 他 们把曲轴封闭起来 润滑系统中的油泵从油底壳抽取油 并将其发送到发动机 的所有工作部件 润滑油排出和回流到油底壳 因此 润滑油在发动机的轴箱 与工作着的零件之间不断地循环 2 3 1 Piston Assembly 活塞总成活塞总成 The piston is an important part of a four stroke cycle engine Most pistons are made from cast aluminum The piston through the connecting rod transfers to the crankshaft the force create by the burning fuel mixture This force turns the crankshaft Thin circular steel bands fit into grooves around the piston to seal the bottom of the combustion chamber These bands are called piston rings The grooves into which they fit are called ring grooves A piston pin fits into a round hole in the piston The piston pin joins the piston to the connecting rod The thick part of the piston that holds the piston is the pin boss 活塞是四个运动周期中一个重要部分 很多活塞都是由铝铸成 活塞 通过连杆传 递力到曲轴通过混合气燃烧 这些力转化为曲柄的动能 这样 圆形的钢圈装入 汽缸 用活塞环来密封整个燃烧室 这个称为活塞环 这些用来放活塞环的称为 凹槽 一个活塞销放在中间通过一个小孔固定 活塞销的作用是固定活塞于连 杆之间的连接 对活塞销起作用的是活塞销凸台 2 3 2 Piston 活塞活塞 To withstand the heat of the combustion chamber the piston must be strong It also must be light since it travels at high speeds as it moves up and down inside the cylinder The piston is hollow It is thick at the top where it take the brunt of the heat and the expansion force It is thin at the bottom where there is less heat The top part of the piston is the head or crown The thin part is the skirt The sections between the ring grooves are called ring lands 为了抵抗燃烧室的高温 活塞必须非常坚固 但是也必须轻便 因为它是在气缸内高速运转而上下运动的 活塞内是空的 在顶部是厚的用来传递高温高压的气体动力 底部温度较低所以做成薄的 顶 部是活塞头或活塞顶 薄部分是裙部 两节之间的凹槽称为环带 The piston crown may be flat concave dome or recessed In diesel engine the combustion chamber may be formed totally or in part in the piston crown depending on the method of injection So they use pistons with different shapes 活塞顶可以是平的 凹的 圆顶的或是隐蔽的 在柴油机的燃烧可能形成完全 或部分活塞冠 依靠这种方法喷射 所以活塞采用不同的形状 2 3 3Piston Rings 活塞环活塞环 In modern engines each piston has three rings Piston in older engines sometimes had four rings or even five the inside surface of the ring fits in the groove on the piston The ring s outside surface presses against the cylinder walls Rings provide the needed seal between the piston and the cylinder walls That is only the rings contact the cylinder walls The top two rings are to keep the gases in the cylinder and are called compression rings The lower one prevents the oil splashed onto the cylinder bore from entering the combustion chamber and is called an oil ring Chrome face cast iron compression rings are commonly used in automobile engines The chrome face provide a very smooth wear resistant surface 现在的发动机 每个活塞有三个活塞环 老式的发动机有四个甚至五个 活 塞环装在活塞内表面的凹槽内 活塞环的外表面紧靠着汽缸壁 活塞环提供了活 塞环于汽缸壁之间的密封 也就是说 只有活塞环接触汽缸壁 顶头两个活塞 环是防止气体从汽缸壁漏出的 称为压缩环 最底下的一个是防止汽油飞溅到 缸桶而从间隙进入到燃烧室 所以称为油环 表面镀铬的铸铁压缩环一般用于 汽车的发动机 镀铬的活塞环提供了光滑 耐磨的表面 During the power stoke combustion pressure on the combustion rings is very high It causes them to untwist Some of the high pressure gas gets in back of the rings This force the ring face into full contact with the cylinder wall The combustion pressure also holds the bottom of the ring tightly against the bottom of the ring groove Therefore high combustion pressure causes a tighter seal between the ring face and the cylinder wall 在做功行程在做功行程 燃烧室对压缩环的压力是非常大的 原因是他们朝汽缸壁方向挤 开 一些高压的气体进入到活塞环 这样使得活塞环表面充分接触到汽缸壁 燃烧的气体压力使得活塞环底部紧紧地压住活塞凹槽 然而 越高的燃烧的气 体压力更加紧紧地把活塞环表面和汽缸壁密封住 2 3 4 Piston Pin 活塞销活塞销 The piston pin holds together the piston and the connecting rod This pin fits into the piston pin holes and into a hole in the top end of the connecting rod The top end of is much smaller than the end that fits on the crankshaft This small end fits inside the bottom of the piston The piston pin fits through one side of the piston through the small end of the rod and then through the other side of the piston It holds the rod firmly in place in the center of the piston Pins are made of high strengh steel and have a hollow center Many pins are chrome plated to help them wear better 活塞销是用来连接活塞于连杆的 活塞销装入销孔 装入连杆最顶头的小孔 连杆的顶部应远小于连杆的尾部才能装进曲柄轴颈 小的底部装进活塞的内底 部 活塞销通过一边装入活塞销 通过小的连杆一端 然后通过活塞的另一边 这使得连杆稳固地在活塞中间适当的位置 活塞销是是空心的且是高强度的钢 制成的 很多销的镀铬的使得更加耐磨 2 3 3 Connecting rod 连杆连杆 The connecting rod is made of forged high strength steel It transmits and motion from the piston to the crankpin on the crankshaft The connecting rod little end is connected to the piston pin A bush made from a soft metal such as bronze is used for this joint The lower end of the connecting rod fits the crankshaft journal This is called the big end For this big end bearing steel backed lead or tin shell bearing are used These are the same as those used for the main bearings The split of the big end is sometimes at an angle so that it is small enough to be withdrawn through the cylinder bore The connecting rod is made from forged alloy steel 连杆是高强度的钢铸造的 它通过曲柄轴颈传递力和运动从活塞到曲柄销 连 杆小的一头是连接活塞销的 轴瓦是用软金属制成的 比如青铜 用来这样合 成的 下级的连杆装进曲柄轴颈 这称为大头 这个轴承 是钢背的铅或者是 锡壳制成的 这些是一样被用作主要轴承 大端的分离切口往往是单个的 所 以它足够小可以从燃烧室中取出 连杆由合金钢铸成 2 3 5 Crankshaft 曲轴曲轴 The crankshaft in conjunction with the connecting rod coverts the reciprocating motion of the piston to the rotary motion needed to drive the vehicle It is usually made from carbon steel which is alloyed with a small proportion of nickel The main bearing journals fit into the cylinder block and the big end journals align with the connecting rods At the rear end of the crankshaft is attached the flywheel and at the front end are the driving whells for the timing gears fan cooling water and alternator 曲轴 连同连杆通过旋转而带动活塞往复运动从而带动汽车行驶 它是由碳钢 和低比例的镍合成的 主要的曲轴轴颈装进汽缸 大端匹配连杆 在曲轴的后 端附加有飞轮 在曲轴的前端有驱动轮对应的正时齿轮 风扇 冷却水和发电 机 The throw of the crankshaft the distance between the main journal and the big end centers controls the length of the stroke The stroke is double the throw and the stroke length is the distance that the piston travels from TDC to BDC and vice versa 曲轴的摆幅 i e 是主要的轴颈和大端中心之间的距离 控制冲程的幅 度 冲程是双次进行的 摆动的幅度是活塞从 TDC 到 BDC 的距离 反之亦然 2 3 6 Flywheel The flywheel is the made from carbon steel It fit s onto the rear of the crankshaft As well as keeping the engine rotating between power strokes it also carries the clutch which transmits the drive to the transmission and has the starter ring gear around its circumference There is only one working stroke in four so a flywheel is needed to drive the crankshaft during the time that the engine is performing the non power strokes 飞轮有碳钢制成 装在曲轴的后端 同时带动曲轴旋转和离合器 同时传送给 变速器 和启动齿圈包围着 在四个冲程当中只有一个冲程是做功的所以飞轮 只有在这个时间带动曲轴 发动机在这几个不做功的冲程转动 2 Push rod Valve Train 推杆气门传动推杆气门传动 In this arrangement the cam lobs push against round metal cylinders called follower As the lobe of the cam comes up and down the cam follower it pushes the cam follower upward away from the camshaft The cam follower rides against a push rod which pushes against a rocker arm The rocker arm pivots on a shaft through its center As one side of the rocker arm moves up the other side moves down just like a seesaw The downward moving side of the rocker arm pushes on the valve stem to open the valve 在这种布置中 凸轮凸起推向叫做凸轮挺杆的圆形金属杆 当凸轮的凸起 运动到凸轮挺杆下时 它推动凸轮挺杆向上 远离凸轮轴 凸轮挺杆顶在推杆 推杆推向摇臂 摇臂绕一根轴中心转动 当摇臂的一端向上运动时 另一端向 下运动 恰象一个翘翘板 摇臂的向下的一端推上阀杆打开气阀 2 4 2 Valve Clearance 气门间隙气门间隙 When the engine runs in compression stroke and power stroke the valves must close tightly on their seats to produce a gas tight seal and thus prevent the gases escaping from the combustion chamber If the valves do not close fully the engine will not develop fill power Also the valve heads will be liable to be brunt by the passing hot gases and there is the likelihood of crown touching an open valve which can seriously damage the engine 当发动机工作在压缩和出力冲程时 气阀必须紧紧地关闭在它的阀座上以 产生气密 因此防止气体从燃烧室泄漏 如果气阀不能完全关闭 发动机就不 能产生全动力 而且气门头部容易被通过的热气体的冲击 并有可能性碰到气门罩 使 发动机严重损坏 So that the valves can close fully some clearance is needed in the operating mechanism This means that the operating mechanism must be able to move sufficiently far enough away from the valve t allow the valves to be fully closed against its seat by the valve spring However if the clearance is set too great this will cause a light metallic taping noise 所以在气门传动机构中要预留一些间隙 使气门得以完全关闭 这就是说 气门传动 机 构运动要与气门有一个充分远的距离 使得气门在气门弹簧作用下紧闭气门座 可是如果 间 隙过大 会引起轻微的金属敲打声 2 4 3 Valve Timing 配气正时 The time at which valves open and close valve timing and the duration of the valve opening in stated in degrees of crankshaft rotation For example the intake valve normally begins to open just before the piston has reached the top dead center The valve remains open as the piston travels down to BDC and even past BDC This is intake valve duration An example of this could be stated as follows IO at 17BTDC IC at 51ABDC or intake opens 17before top dead center intake closes 51after bottom dead center Intake valve duration in this case is 248 of crankshaft rotation 气阀打开和关闭的时间和气阀打开的时长用曲轴转动的角度表示 例如 进气 阀恰在活塞到达上止点前正常地开始打开 它在活塞向下移动到 BDC 甚至过 BDC 时仍保持打开 这是进气阀打开持续时间 这个例子可以说明为 进气阀 在 17 BTDC 打开 进气阀在 51 ABDC 关闭 在这种情况下 进气阀打开持续 时间是曲轴转过 248 It is apparent from this description that the exhaust valve stays open for a short period of time during which the intake valve is also open In other words the end of the exhaust stroke and the beginning of the intake stroke overlap for a short period of time This is called valve overlap Valve timing and valve overlap vary on different engines 根据这个说明 在进气阀打开时 排气阀仍保持打开一小段时间 换句话说 排气冲程结束前和进气冲程开始后重叠一小段时间 这叫气门重叠 Opening the intake valve before TDC and closing it after BDC increase the fill of air fuel mixture in the cylinder Opening the intake valve early helps overcome the static inertia of the air fuel mixture at the beginning of the intake stroke while leaving the intake valve open after BDC takes advantage of the kentia of the moving air fuel mixture This increase volumetric efficiency 在 TDC 前打开进气阀和在 BDC 后关闭它增加了注入气缸的燃料混合气量 早一 点打开进气阀有助于在进气冲程开始时克服燃料混合气的静止惯性 而进气阀 在 BDC 后打开则利于运动的燃料混合气的动态惯性 这提高了容积效率 As the piston moves down on the power stroke past the 90 ATDC position pressure in the cylinder has dropped and the leverage to the crankshaft has decreased due to connecting rod angle and crankshaft position This ends the effective length of the power stroke and the exhaust valve can now be opened to begin expelling the burned gases The exhaust valve remains open until the piston has moved up past the TDC position This helps to remove as much of the burned gases as is possible and increase volumetric efficiency 当活塞在出力冲程阶段向下运动过 TDC 位置后的 90 处 气缸内压力降低 由 于连杆角和曲柄轴位置 对曲柄轴的杠杆作用力已经减小 这结束出力行程的 有效长度 现在排气阀可能打开 开始排出燃烧过的气体 直到活塞向上运动 过 TDC 位置时 排气阀一直打开 这有助于燃烧过的气体尽可能多地排出 因 此提高了容积效率 The entire valve train assembly can be viewed as a spring mass system in which the conversion from stored to ree energy causes forced vibration Valve train assemblies with overhead camshafts can be represented with sufficient accuracy by a 1 mass system consisting of the moving mass the valve train assembly stiffness and corresponding damping 整个气门机构总成可看成一个弹簧 质量系统 其储存的能量转化为自由能量时会引起受迫 振动 带有顶置凸轮轴的气门机构可非常精确地用单质量系统来表示 由运动质量 气门 机构的刚度和相应的阻尼组成 2 4 5 Camshaft Drive Mechanism 凸轮轴驱动机构凸轮轴驱动机构 Each cam must revolve once during the four stroke cycle to open a valve A cycle remember corresponds with two revolutions of the crankshaft Therefore the camshaft must revolve at exactly half the speed of the crankshaft This is accomplished with a 2 1 gear ratio A gear connected to the camshaft has twice the number of teeth as a gear connected to the crankshaft The gears are linked in one of three ways 在四冲程循环中 每个凸轮必须转动一次以打开气阀 记住 一个循环相当于 曲轴的两转 因此 凸轮轴必须精确地以曲轴速度的一半转动 这是以 2 1 的 齿轮比实现的 一个装到凸轮轴上的齿轮的齿数是装到曲轴上的齿轮齿数的两 倍 这些齿轮的连接方式有三种 1 Belt Drive皮带传动 A cog type belt can be used Such belts are made of synthetic rubber and reinforced with internal steel or fiberglass strands The belts have teeth or slotted spaces to engage and drive teeth on gear wheels A belt typically is used on engines with overhead cam valve trains 可用齿型带 这些皮带用合成橡胶制造并用内置钢或玻璃纤维强化 皮带有齿 或槽型空间与齿轮上的齿啮合并驱动 皮带典型地用在顶置凸轮气阀传动的发 动机上 2 Chain Drive链传动 On some engines a metal chain is used to connect the crankshaft and camshaft gears Most push rod engines and some OHC engines have chains 在一些发动机上 采用金属链连接曲轴和凸轮齿轮 大多数推杆发动机和 OHC 发动机采用这种方式 3 Gear Drive齿轮传动 The camshaft and crankshaft gears can be connected directly or meshed This type of operating linkage commonly is used on older six cylinder inline engines A camshaft driven by a chain or belt turns in the same direction as the crankshaft But a Camshaft driven directly by the crankshaft gear turns in the opposite direction Timing belts are used because they cost less than chains and operate more quietly A typical timing belt is made of neoprene synthetic rubber reinforced with fiberglass 凸轮轴和曲柄轴直接连接或啮合 这种类型的连接常用于老式 6 缸 直列发动 机上 用链或皮带传动的凸轮轴与曲轴的转动方向相同 但直接由曲轴齿轮传动传动 的凸轮轴以相反的方向转动 采用正时皮带因为它们的成本比链传动低得多 且运转更安静 典型的正时皮带是用氯丁橡胶 合成橡胶 制造 用玻璃纤维 强化 2 4 6 Electronic Valve Control System 电子气阀控制系统 An electronic value control EVC system replaces the mechanical camshaft controlling each value with