《汽车专业英语》课程教学资源（PPT课件讲稿，英文版）UNIT 4 GASOLINE FUEL INJECTION

PROFESSIONAL ENGLISH UNIT 4 GASOLINE FUEL INJECTION TEXT B Operation of the Motronic System

UNIT 4 GASOLINE FUEL INJECTION TEXT B Operation of the Motronic System PROFESSIONAL ENGLISH

本次课学习内容 UNIT 4 GASOLINE FUEL INJECTION TEXT B Operation of the Motronic system Start Control( Fuel, Ignition Timing, Air e Post-Start Varm-Up Closed-Loop Operation e Part-Throttle Acceleration Full-Load Acceleration ● Knock Control RPM Limitation Coasting Cut-Off

UNIT 4 GASOLINE FUEL INJECTION TEXT B Operation of the Motronic System • Start Control ( Fuel, Ignition Timing, Air) • Post-Start • Warm-Up • Closed-Loop Operation • Part-Throttle Acceleration • Full-Load Acceleration • Knock Control • RPM Limitation • Coasting Cut-Off 本次课学习内容

本次课学习目标 ●掌握MTR0NIC系统的控制原理 ●掌握有关控制原理的专用术语 ●了解翻译技巧—句子成分转换

本次课学习目标 ⚫ 掌握MOTRONIC系统的控制原理 ⚫ 掌握有关控制原理的专用术语 ⚫ 了解翻译技巧—句子成分转换

NEW WORDS flood [tind]v充满,淹没,溢出;n.洪水 compensate [k。 mpenseit]v补偿,偿还 formation[:' meiLan]n形成,形成量 turbocharge [te: bouta:dv用涡轮增压 turbo [tabou]n涡轮增压,涡轮增压器 intercooler[intake:la]n中间冷却器,中冷器 sense [sens]v理解,感到,感受,检测 override[ouvo' raid]v超过(越),越过,压倒,占优势 overswing[ ouve'swinⅣ.摆动过大 am bda[ faemde]nA值,过量空气系数,氧传感器 endanger [in 'deind]v危及 trait [treit]n特性,显著的特点 harmonics[ha:m。niks]n谐波音],谐波分量

NEW WORDS flood [flʌd]v.充满，淹没，溢出；n.洪水 compensate [‘kɔmpenseit]v.补偿，偿还 formation [fɔ:‘mei∫ən]n.形成，形成量 turbocharge [‘tə:bout∫ɑ:ʤ]v.用涡轮增压 turbo [’təbou]n.涡轮增压，涡轮增压器 intercooler [intə‘ku:lə]n.中间冷却器，中冷器 sense [sens]v.理解，感到，感受，检测 override [ouvə‘raid]v.超过（越），越过，压倒，占优势 overswing [ouvə‘swiŋ]v.摆动过大 lambda [‘læmdə]n. λ值，过量空气系数，氧传感器 endanger [in‘deinʤə]v.危及 trait [treit]n.特性，显著的特点 harmonics [hɑ: ‘mɔniks]n.谐波[音]，谐波分量

recognition [reka nij(e)nn承认,赏识,赞誉 modify ['madifaijv.更改,修改 stratification[ stratifi keijan]n成层,分层 cutback[ kAtbaek]n减少 scope[ soup]n范围,领域,见识,示波器,指示器 simultaneous[ simal'teinjas]a同时的,同时发生的,同步的 coast [oust]v滑行,滑翔,沿海岸航行;n.海岸,沿岸 cut-off[kAtef]n切断,关闭,停车 coastdown[ koustdaun]n降低,下降,滑行 blank[ blank]ad空白的,空着的,没有表情的;n空白 stall [st:]V失速,熄火,(速度不够)停车停止转动 refinement [ri fainment]n精致,文雅,精巧 resume[ [rizju:m]v恢复,重新开始

recognition [rekəg‘ni∫(ə)n]n.承认，赏识，赞誉 modify [‘mɔdifai]v.更改，修改 stratification [ֽstrætifi‘kei∫ən]n.成层，分层 cutback [‘kʌtbæk]n.减少 scope [skoup]n.范围，领域，见识，示波器，指示器 simultaneous [siməl‘teinjəs]a.同时的，同时发生的，同步的 coast [koust]v.滑行，滑翔，沿海岸航行；n.海岸，沿岸 cut-off [‘kʌtəf]n.切断，关闭，停车 coastdown [‘koustdaun]n.降低，下降，滑行 blank [blæŋk]ad.空白的，空着的，没有表情的；n.空白 stall [stɔ:l]v.失速，熄火，（速度不够）停车[停止转动] refinement [ri‘fainmənt]n.精致，文雅，精巧 resume [ri'zju:m]v.恢复, 重新开始

PHRASES AND EXPRESSIONS port injector进气道喷油器 start injector起动喷油器,冷起动喷油器 thermo- time switch温控定时开关 turbocharged car涡轮增压轿车 air- fuel ratio空燃比 knock sensor爆燃传感器 passenger com partment乘客舱,乘员室 knock control regulator爆燃控制调节器 be sorted from与.分开,从.拣出 scope set示波器

port injector 进气道喷油器 start injector 起动喷油器，冷起动喷油器 thermo-time switch 温控定时开关 turbocharged car 涡轮增压轿车 air-fuel ratio 空燃比 knock sensor 爆燃传感器 passenger compartment 乘客舱，乘员室 knock control regulator 爆燃控制调节器 be sorted from 与…分开，从…拣出 scope set 示波器 PHRASES AND EXPRESSIONS

Operation of the Motronic System In this section, let's look at operating conditions to see how Motronic controls injection and ignition as well as idle speed bypass air for good engine management [11 Starting Start Control. fuel In most Motronics, start enrichment is provided by the port injectors rather than the separate start injector/thermo-time switch For start control, the important inputs are rpm and engine temperature. The control unit monitors cranking rpm and also the number of revolutions since the time cranking began [2. The injection pulses may be longer than normal But at low engine temperatures, the control unit may deliver instead several shorter injection pulses per revolution to improve starting. Remember, these are 10 millisecond pulses in a pulse period, or crankshaft revolution time of 200ms

Operation of the Motronic System In this section, let's look at operating conditions to see how Motronic controls injection and ignition as well as idle￾speed bypass air for good engine management [1]. Starting Start Control, Fuel In most Motronics, start enrichment is provided by the port injectors rather than the separate start injector/thermo-time switch. For start control, the important inputs are rpm and engine temperature. The control unit monitors cranking rpm, and also the number of revolutions since the time cranking began [2]. The injection pulses may be longer than normal. But at low engine temperatures, the control unit may deliver instead several shorter injection pulses per revolution to improve starting. Remember, these are 10 millisecond pulses in a pulse period, or crankshaft revolution time of 200ms

To prevent flooding fuel quantity will cut back after a measured number of revolutions or after the engine has reached a cranking rpm that is temperature related, for example 200-300 Start Control, Ignition Timing With a cold engine at low cranking speeds, timing will be controlled near TDC. For normal cranking rpm, a large advance in timing might fire too early, damaging the starter. Further, starting would be difficult if not impossible. With a cold engine at higher cranking rpm, however, timing will be advanced for better starting For hot starts, or high intake air temperatures, timing will be retarded because a hot cylinder can fire easier while the piston is rising at cranking rpm. Retarded timing prevents knocking that can occur in high-compression engines, and may be masked by the starter sound Start Control. air As in L-Jetronic, the idle-speed stabilizer is normally driven open more by increased dwell signals to provide extra bypass air for cold starting

To prevent flooding, fuel quantity will cut back after a measured number of revolutions, or after the engine has reached a cranking rpm that is temperature related, for example 200-300 rpm. Start Control, Ignition Timing With a cold engine at low cranking speeds, timing will be controlled near TDC. For normal cranking rpm, a large advance in timing might fire too early, damaging the starter. Further, starting would be difficult if not impossible. With a cold engine at higher cranking rpm, however, timing will be advanced for better starting. For hot starts, or high intake air temperatures, timing will be retarded because a hot cylinder can fire easier while the piston is rising at cranking rpm. Retarded timing prevents knocking that can occur in high-compression engines, and may be masked by the starter sound. Start Control, Air As in L-Jetronic, the idle-speed stabilizer is normally driven open more by increased dwell signals to provide extra bypass air for cold starting

Post-Start Post-start-the 5-30 seconds when you want the engine to keep running after you release the key from CranK-is affected by engine temperature as well as a timer in the control unit. Colder engines get more fuel injected. Also colder engines get more timing advance. Based on the start up temperature, and the time since start, post-start enrichment is gradually reduced. The idle-speed stabilizer maintains rpm Warm-Up During warm up, the most important input, besides engine load and rpm for basic pulse time, is engine temperature. The control unit includes a rom map of warm-up characteristics to apply a correction factor based on load and engine speed greater at low loads and rpm than at high loads and rpms [3] ee Fig 4-4. Control unit outputs include injection pulses for the proper mixture, ignition timing for driveability(advance under part-load acceleration, retard on deceleration to reduce HC emissions), and idle stabilization to help keep the engine running at idle

Post-Start Post-start-the 5-30 seconds when you want the engine to keep running after you release the key from CRANK-is affected by engine temperature as well as a timer in the control unit. Colder engines get more fuel injected. Also, colder engines get more timing advance. Based on the start￾up temperature, and the time since start, post-start enrichment is gradually reduced. The idle-speed stabilizer maintains rpm. Warm-Up During warm up, the most important input, besides engine load and rpm for basic pulse time, is engine temperature. The control unit includes a ROM map of warm-up characteristics to apply a correction factor based on load and engine speed, greater at low loads and rpm than at high loads and rpms [3], See Fig.4-4. Control unit outputs include injection pulses for the proper mixture, ignition timing for driveability (advance under part-load acceleration, retard on deceleration to reduce HC emissions), and idle stabilization to help keep the engine running at idle

Remember, during warm-up, the temperature of the lambda sensor is important. Unheated lambda sensors can be heated faster by changing ignition timing. Motronic retards timing to cause a hotter exhaust. That heats the oxygen sensor much quicker and also heats the catalytic converter faster for more efficiency correction factors ine Fig 4-4 Warm-up correction factors

Fig.4-4 Warm-up correction factors Remember, during warm-up, the temperature of the lambda sensor is important. Unheated lambda sensors can be heated faster by changing ignition timing. Motronic retards timing to cause a hotter exhaust. That heats the oxygen sensor much quicker and also heats the catalytic converter faster for more efficiency