汽车专业英语读译教程 宋进桂- 6-本E-GAS-GDI-新

1、 ELECTRONIC FUEL INJECTION （2）Electronic ThrottleDrive-By-WireGDIGasoline Direct InjectionDiesel Common Rail Injection SystemPROFESSONAL ENGLISH: NEW TECHNOLOGIES8/12/20221 NewWordsoctane-rating 辛烷值take advantage of 利用 运用anti-knock index 抗爆指数scope set 示波器stipulate 约定，规定Coast v.滑行 blank 空白（的） 空地 空虚的

2、approache v.接近 达到 stall 熄火retard 延迟，推迟 mask 掩盖 overswing 尖峰 突增 jerk 急拉动，撞，跳, 振动（冲击） 颠簸地行进 rich 富的 浓的 丰富多彩的enrichment 加浓freedom 自由(度） 灵活性 freedom from 免除（于）turbocharge v.(涡轮)增压turbo 涡轮 涡轮增压器form v.形成 n.形式 形态 形状 式样ELECTRONIC FUEL INJECTION8/12/20222Electronic ThrottleDrive-By-Wire Some of the newest M

3、otronic systems have an electronic throttle (also known as a drive-by-wire system). The electronic throttle has no mechanical link between the accelerator pedal and the throttle valve. Instead, as shown in the Figure on next page, an accelerator sensor picks up your movement or position of the accel

4、erator pedal. It signals the control unit about pedal movement, and the control unit signals the servomotor on the throttle shaft to open. The electronic throttle (Bosch calls it EGAS) may sound like something none of us needs, but it has many benefits.ELECTRONIC FUEL INJECTION sound like 听起来好像8/12/

5、20223Fig. 4-29. Electronic throttle sends accelerator signal to Motronic control unit . DC motor moves throttle valve, modified by engine temperature, idle rpm, and maximum rpmELECTRONIC FUEL INJECTION8/12/20224The throttle opening signal may be modified according to engine rpm and engine temperatur

6、e. It can provide simplified cruise control. It can also control minimum rpm, replacing the idle-speed stabilizer, and control maximum rpm, replacing the alternate-injector cut-out. But theres more. For traction control, the electronic throttle links with the ABS (Anti-lock Braking System). The same

7、 wheel- speed sensors of ABS also feed the ASR (Anti-Slip Regulator).When any driving wheel starts to slip, a slight brake application prevents that wheel from slipping so much that the differential delivers no power to the other driving wheel. If both driving wheels show signs of slipping, the elec

8、tronic throttle cuts back power for maximum control gives the car the max acceleration the tires can deliver to the road. If laying down tire smoke is your thing, avoid ASR. But for making the fastest takeoff, you cannot beat it.ELECTRONIC FUEL INJECTIONlaying down 主张，搁下，放弃 beat 冲击，敲打 trust 相信，信赖8/1

9、2/20225Can you trust the electronic throttle? Will it provide unintended acceleration? The system checks its safety circuits before start-off, and reports defects to the driver. If a defect is found, a limp-home circuit may disable some of the functions, but it will allow you to get to the house or

10、the shop. It may well be more reliable than some cable actuated throttles. trust 相信，信赖 defect 故障，缺点，毛病 limp-home 跛行回家ELECTRONIC FUEL INJECTION8/12/20226Gasoline Direct Injection Conventional gasoline engines are designed to use an electronic fuel injection system, replacing the traditional mechanica

11、l carburetion system. Multi-point injection (MPI), where the fuel is injected through each intake port, is currently one of the most widely used systems. Although MPI provides a drastic improvement in response and combustion quality, it is still limited due to fuel and air mixing prior to entering t

12、he cylinder. To further increase response time and combustion efficiency, while lowering fuel consumption and increasing output, systems may use direct injection. Gasoline direct injection engines are engineered to inject the gasoline directly into the cylinder in a manner similar to diesel direct i

13、njection engines.ELECTRONIC FUEL INJECTION8/12/20227 Direct injection is designed to allow greater control and precision, resulting in better fuel economy. This is accomplished by enabling combustion of an ultra-lean mixture under many operating conditions. Direct injection is also designed to allow

14、 higher compression ratios, delivering higher performance with lower fuel consumption. Currently, direct injection gasoline engines are being deployed throughout the world in passenger cars.Mitsubishi GDI Mitsubishi Motors is aiming to achieve both low fuel consumption and high output. MMC is a worl

15、d forerunner in the development of direct cylinder injection gasoline engines, known as GDI, which were first introduced in the 1996 Galant. GDI supplies fuel directly to the inside of the cylinder (Figure). A variety of air-fuel mixtures can be created according to changes in the fuel injection tim

16、ing. ELECTRONIC FUEL INJECTION8/12/20228Fig.4-1 Mitsubishi direct cylinder injection gasoline engineELECTRONIC FUEL INJECTION8/12/20229ELECTRONIC FUEL INJECTION8/12/2022102.7.4 Common Rail Injection System (CR System) All previous injection systems have one disadvantage in common (Fig. 2-30): the pr

17、essure generation and the supply of the injection quantity are not mutually independent. The result is that the injection pressure increases with the engine speed and also increases during injection ( approximately linearly). Consequently, smaller injection quantities are injected with low pressure.

18、 The peak pressure is almost twice as high as the average injection pressure, which is responsible for the quality of the fuel swirl in the combustion chamber. ELECTRONIC FUEL INJECTION be responsible for 对负责，是的主要原因，决定着8/12/202211ELECTRONIC FUEL INJECTION8/12/202212 An injection system is desirable

19、in which 1) injection pressure and fuel quantity can be adjusted independently, 2) the injection pressure is as high and as constant as possible during the entire injection after combustion start, 3) the injection quantity or injection pressure at the start of injection, i.e. During the ignition lag

20、 between the start of injection and start of combustion (depending on engine temperature, several hundred Its up to over 1ms) is as low as possible. ELECTRONIC FUEL INJECTION8/12/202213 Targets 1 and 2 can be achieved By a common rail injection system (Fig. 2-31 ). A pressure accumulat or is supplie

21、d with fuel by a high-pressure pump (Common Rail). The pressure in the common rail is measured with a pressure sensor and settled to a constant value by a pressure-control valve in the high-pressure pump. Depending on the requirements of combustion, the pressure in the rail can be maintained, largel

22、y independent of the engine speed, at a constant value in the range between 15 - 140MPa.ELECTRONIC FUEL INJECTIONsettle 稳定，决算 8/12/202214ELECTRONIC FUEL INJECTION8/12/202215ELECTRONIC FUEL INJECTION8/12/202216ELECTRONIC FUEL INJECTION8/12/202217 The pressure accumulator is connected to the injectors with short lines. In addition to the injection nozzles, the injectors contain a servo solenoid valve. The control unit initiates the injection by switching on the solenoid valve; injection is terminated by switching it off