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单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,*,*,汽车专业英语,Unit 2,汽车专业英语Unit 2,1,2-1 Four Cylinder Inline Gasoline Engine直列四缸汽油机,2-1 Four Cylinder Inline Gaso,2,1-intake air tank 进气室 2-throttle valve 节气门,3-cylinder head 气缸盖 4-cylinder 气缸,5a-exhaust gas manifold with catalytic converter,带催化转化器的排气歧管,5-cylinder block 气缸体 6-flywheel 飞轮,7-cylinder jacket 气缸水套 8-piston 活塞,9-oil pan 油底壳 10-crank shaft 曲轴,11-timing belt pulley 正时带轮 12-crank shaft pulley 曲轴带轮,13-timing belt 正时齿带 14-camshaft 凸轮轴,15-timing belt cover 正时齿带罩,16-spark plug 火花塞,1-intake air tank,3,The Inline Engine,We all know the engine is the,heart of the automobile.What is the core of the engine?Yes,its the cylinder.Most cars have more than one cylinder(four,six and eight cylinders are common).In a multi-cylinder engine,the cylinders usually are arranged in one of three ways:inline,V or flat.,The Inline EngineWe all know,4,In an inline engine,the cylinders are arranged in a line in a single bank.The inline arrangement is the simplest and most common one and has many advantages.First,the engine has a good stability and more power.Second,the structures of the cylinder block and the crankshaft are very simple and they share only one cylinder head.The cost to manufacture and install is less.,In an inline engine,the cylin,5,Because of these advantages,BMW and also many American car manufactures like to use the inline cylinder engine.This kind of engine is widely used in the cars made in home.,Because of these advantages,B,6,2-2 Basic Terms of Engine 发动机基本术语,2-2 Basic Terms of Engine 发,7,TDC=top dead center,top center,outer dead center 上止点,BDC=bottom dead center,bottom center,inner dead center 下止点,S=piston stroke,piston travel 活塞行程,Sk=piston clearance from TDC 活塞离上止点距离,r=crank radius 曲柄半径,=crank angle,crankshaft angle 曲柄角,Vh=swept volume of a cylinder或piston displacement或,cylinder swept volume 气缸工作体积,每缸排量,VC=combustion volume或 combustion chamber(space)volume 或,cylinder compression volume 燃烧室容积,VC+Vh=cylinder total volume 气缸总容积,(VC+Vh)/VC=compression ratio 压缩比,TDC=top dead center,top ce,8,Main Terms,There are many terms in describing the operations of an automobile engine.Lets see some basic terms.,Stroke,refers to piston movement.A stroke occurs when the piston moves from one extreme position to the other extreme position inside the engine cylinder.The highest position that the piston reaches inside the cylinder is called,TDC,(top dead center).Similarly,the lowest position that the piston reaches inside the cylinder is called,BDC,(bottom dead center).So we can also say a stroke is piston movement from TDC to BDC or vice versa.,Main TermsThere are many terms,9,During the induction stroke,the volume of air/fuel mixture to fill a single cylinder is swept by the piston;this volume is called the,swept volume,.During the compression stoke,the swept volume is compressed into a small space above the piston.And at this time,the piston reaches the top of the cylinder.The space is called as the,clearance volume,.The clearance volume and the swept volume determine the,compression ratio,.Generally,a high compression ratio is good for performance and efficiency.,During the induction stroke,t,10,2-3 Four-Stroke Engine 四冲程发动机,A-intake stroke或suction stroke 进气行程,The intake valve is open while the exhaust valve is close.进气门开启而排气门关闭。,IV=intake valve 进气门,EV=exhaust valve 排气门,2-3 Four-Stroke Engine 四冲程发,11,B-compression stroke,compression travel 压缩行程,Both the intake and exhaust valves are close.,进气门和排气门均关闭。,B-compression stroke,comp,12,C-power stroke,combustion,working stroke,firing stroke,expansion stroke 膨胀(作功)行程,Both the intake and exhaust valves are close.进气门和排气门均关闭。,C-power stroke,combustion,13,D-exhaust stroke 排气行程,The intake valve is close while the exhaust valve is open.进气门开启而排气门关闭。,D-exhaust stroke,14,Four-Stroke Engine Cycle,The four stroke engine was first invented by Nikolaus August Otto(18321891)in 1876,so it is also known as the Otto cycle.The four stroke engine is probably the most common engine type nowadays.It powers almost all cars and trucks.,Four-Stroke Engine CycleThe f,15,The four strokes of the cycle are intake,compression,power,and exhaust.To complete the full cycle it takes two revolutions of the crankshaft.A 4-stroke gasoline engine uses internal combustion.,The four strokes of the cycle,16,The intake stroke starts with the exhaust valve closed,the inlet valve opening,and the piston at its highest point,top dead center.It starts to move down,increasing the volume above the top of the piston.This makes pressure inside the cylinder lower than the pressure outside.This higher outside air pressure forces the air-fuel mixture into the cylinder.The piston reaches bottom dead center,the inlet valve closes,and the intake stroke ends.,The intake stroke starts with,17,Both intake and exhaust valves stay closed as the piston leaves bottom dead center.The piston moves up,which compresses the volume of the air-fuel mixture.That causes the air/fuel charges temperature to rise,and that makes ignition easier and combustion(burning of fuel)more complete.Just before the piston reaches top dead center,ignition occurs.The air expanding in the cylinder pushes the piston down the cylinder.This is the Power stroke that drives the engine.,Both intake and exhaust valve,18,The piston now moves from bottom dead center to top dead center.The exhaust valve opens,and the piston pushes out the leftover gases.,The piston now moves from bot,19,Lets look at a complete 4-stroke cycle:,Intake-takes in air-fuel mixture.,Compression-squeezes the air-fuel mixture into a smaller and smaller volume.,Power-the mixture under pressure is ignited.The air-fuel mixture burning,Expanding gases push the piston down creating a power stroke.,Exhaust-the piston moves upward,forcing burned gases from the chamber.,Lets look at a complete 4-st,20,2-4 The Components of Cylinder Head 气缸盖零部件,A-gasket 密封垫(圈),1-EGR VSV=EGR vacuum switching valve EGR EGR真空开关阀,EGR=exhaust gas recirculation 废气再循环,2-4 The Components of Cylinde,21,2-EGR valve and vacuum modulator EGR 阀和真空调制器,2-EGR valve and vacuum mod,22,3-throttle body 节气门体,3-throttle body,23,4-cold start injector 冷起动喷油器,5-cold start injector pipe 冷气动喷油器油管,4-cold start injector,24,6-fuel pulsation damper 燃油脉动衰减器,7-delivery pipe 供给管,燃油管,7a-injector 喷油器,8-insulator 隔热套,9-spacer 隔套,6-fuel pulsation damper 燃,25,10-adjusting shim 调整垫片,11-valve lifter 气门挺柱,12-keeper 锁夹,13-spring retainer 弹簧座(保持器),14-valve spring 气门弹簧,15-oil seal 油封,valve stem seal 气门杆油封,16-spring seat 弹簧垫圈,17-valve guide(bushing)气门导管,18-valve 气门,气阀,10-adjusting shim,26,19-engine hanger 发动机吊钩,19-engine hanger,27,20-exhaust manifold 排气歧管,21-heat insulator 隔热罩,汽车专业英语教学-汽车专业英语(第二章),28,22-retainer 保持器,23-cushion 缓冲器,24-catalytic converter,催化转化器,22-retainer,29,25-catalytic converter stay 催化转化器支架,26-lower heat insulator 下隔热罩,25-catalytic converter sta,30,27-alternator bracket 发电机支架,28-cylinder head gasket 气缸盖垫片,27-alternator bracket,31,29-timing belt cover 正时带罩,30-cylinder head 气缸盖,汽车专业英语教学-汽车专业英语(第二章),32,汽车专业英语教学-汽车专业英语(第二章),33,31-snap ring 挡圈,卡坏,32-wave washer 波形垫圈,33-oil seal 油封,34-camshaft sub gear 凸轮轴副齿轮,35-camshaft gear spring 凸轮轴齿轮弹簧,36-camshaft 凸轮轴,36a-intake camshaft 进气凸轮轴,36b-exhaust camshaft 排气凸轮轴,37-camshaft bearing cap 凸轮轴轴承盖,38-spark plug 火花塞,39-cylinder head cover 气缸盖罩,31-snap ring 挡,34,40-intake manifold stay 进气歧管撑条,40-intake manifold stay,35,41-air pipe 空气管,36,42-intake manifold 进气歧管,汽车专业英语教学-汽车专业英语(第二章),37,Cylinder Head,The cylinder head fastens to the top of the block,just as a roof of a house.The underside forms the combustion chamber with the top of the piston.The cylinder head carries the valves,and it has ports to allow air,fuel,and exhaust move through the engine.Like the cylinder block,the head is made from either cast iron or aluminum alloy.,Cylinder Head,38,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.Thus,a gasket is used.Head gaskets are made of thin sheets of soft metal or of asbestos and metal.Gaskets are also used to seal joints between other parts,such as between the oil pan,manifolds,or water pump and the block.,The cylinder head is attached,39,2-5 Lubrication System 润滑系统,2-5 Lubrication System 润滑,40,1-oil pressure switch 油压开关,2-main oil galley 主油道,3-oil filter,或lubrication oil filter 机油滤清器,4-oil cooler 机油冷却器,air oil cooler 风冷式机油冷却器,5-relief valve 限(释)压阀,6-suction strainer 吸入口滤网,oil strainer 机油收集器,pickup pipe and screen 吸入管和滤网,7-oil pump 机油泵,1-oil pressure switch,41,Engine Lubrication System,The engine has many moving parts.The purpose of the lubrication system is to supply lubricant,the oil to all the moving parts of the engine.At the same time,the system separates their surfaces,reduce friction and act as a coolant and detergent.,Engine Lubrication SystemThe,42,The lubrication system includes the following parts:the oil pan,oil pump,main oil galleries,oil filters,oil pressure relief valves,oil cooler and oil sensors.The purpose of the oil pan is to hold the excess oil during operation and non-running conditions.The oil pump is to delivering an adequate volume of oil around the engine at a suitable pressure.The oil pump operates all the time when the engine is running.Oil filter is used to filter and clean the dirt particles getting into the oil when the engine runs.A pressure regulator valve is used to keep the pressure within the oil system at a constant maximum value.The oil cooler helps to keep the oil cool.Oil pressure sensors are used to indicate the right amount of pressure of the oil system.,The lubrication system include,43,2-6 The Fuel System of Diesel Engine 柴油机燃油系统,2-6 The Fuel System of Diesel,44,A-in-line fuel injection pump 直列式喷油泵,B-distributor fuel injection pump 分配式喷油泵,1-fuel tank 燃油箱,2-governor 调速器,3-fuel-supply pump 输油泵,4-fuel injection pump或injection pump 喷油泵,camshaft fuel injection pump 凸轮轴式喷油泵,4a-in-line fuel injection pump 直列式喷油泵,multi-cylinder fuel injection pump 多缸喷油泵,4b-distributor fuel injection pump 分配式喷油泵,5-injection timing device 喷射正时装置,6-drive from engine 来自发动机的驱动力,7-fuel filter 燃油滤清器,8-vent 通气孔,9-injector 喷油器,10-fuel return line 回油管,11-overflow line 溢流管,A-in-line fuel injection p,45,
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