ELECTRONIC FUEL INJECTION （ 2）
Electronic Throttle— Drive-By-Wire
GDI—— Gasoline Direct Injection
Diesel Common Rail Injection System
PROFESSONAL ENGLISH,NEW TECHNOLOGIES
New
Words
octane-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
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 INJECTION
Electronic Throttle—Drive-By-Wire
Some of the newest Motronic 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 accelerator 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
Fig,4-29,
Electronic
throttle
sends
accelerator
signal to
Motronic
control unit,
DC motor
moves
throttle
valve,
modified by
engine
temperature,
idle rpm,and
maximum
rpm
ELECTRONIC FUEL INJECTION
The throttle opening signal may be modified according to
engine rpm and engine temperature,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 there's more,For traction control,the electronic throttle
links with the ABS (Anti-lock Braking System),The same
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 electronic
throttle cuts back power for maximum traction.Traction
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 INJECTION
laying down 主张，搁下，放弃 beat 冲击，敲打 trust 相信，信赖
Can 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 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 INJECTION
Gasoline Direct Injection
Conventional gasoline engines are designed to use an electronic
fuel injection system,replacing the traditional mechanical
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 the 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 injection engines.
ELECTRONIC FUEL INJECTION
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 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 world 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 timing,
ELECTRONIC FUEL INJECTION
Fig.4-1
Mitsubishi
direct
cylinder
injection
gasoline
engine
ELECTRONIC FUEL INJECTION
ELECTRONIC FUEL INJECTION
2.7.4 Common Rail Injection System (CR System)
All previous injection systems have one
disadvantage in common (Fig,2-30),the pressure
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,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
ELECTRONIC FUEL INJECTION
An injection system is desirable 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
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 INJECTION
Targets 1 and 2 can be achieved By a common rail
injection system (Fig,2-31 ).
A pressure accumulat or is supplied 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,largely independent of the engine
speed,at a constant value in the range between 15 -
140MPa.
ELECTRONIC FUEL INJECTION
settle 稳定，决算
ELECTRONIC FUEL INJECTION
ELECTRONIC FUEL INJECTION
ELECTRONIC FUEL INJECTION
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,The
injected fuel quantity is directly proportional to
the switch-on time of the solenoid valve and
independent of the engine/pump speed (pure
time control of the injection quantity).
ELECTRONIC FUEL INJECTION
SUMMARY
Electronic Throttle— Drive-By-Wire
GDI—— Gasoline Direct Injection
Diesel Common Rail Injection System
HOMEWORK
List the advantages of the Drive-By-Wire
List the advantages of the Gasoline Direct Injection
ELECTRONIC FUEL INJECTION
Electronic Throttle— Drive-By-Wire
GDI—— Gasoline Direct Injection
Diesel Common Rail Injection System
PROFESSONAL ENGLISH,NEW TECHNOLOGIES
New
Words
octane-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
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 INJECTION
Electronic Throttle—Drive-By-Wire
Some of the newest Motronic 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 accelerator 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
Fig,4-29,
Electronic
throttle
sends
accelerator
signal to
Motronic
control unit,
DC motor
moves
throttle
valve,
modified by
engine
temperature,
idle rpm,and
maximum
rpm
ELECTRONIC FUEL INJECTION
The throttle opening signal may be modified according to
engine rpm and engine temperature,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 there's more,For traction control,the electronic throttle
links with the ABS (Anti-lock Braking System),The same
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 electronic
throttle cuts back power for maximum traction.Traction
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 INJECTION
laying down 主张，搁下，放弃 beat 冲击，敲打 trust 相信，信赖
Can 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 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 INJECTION
Gasoline Direct Injection
Conventional gasoline engines are designed to use an electronic
fuel injection system,replacing the traditional mechanical
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 the 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 injection engines.
ELECTRONIC FUEL INJECTION
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 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 world 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 timing,
ELECTRONIC FUEL INJECTION
Fig.4-1
Mitsubishi
direct
cylinder
injection
gasoline
engine
ELECTRONIC FUEL INJECTION
ELECTRONIC FUEL INJECTION
2.7.4 Common Rail Injection System (CR System)
All previous injection systems have one
disadvantage in common (Fig,2-30),the pressure
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,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
ELECTRONIC FUEL INJECTION
An injection system is desirable 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
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 INJECTION
Targets 1 and 2 can be achieved By a common rail
injection system (Fig,2-31 ).
A pressure accumulat or is supplied 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,largely independent of the engine
speed,at a constant value in the range between 15 -
140MPa.
ELECTRONIC FUEL INJECTION
settle 稳定，决算
ELECTRONIC FUEL INJECTION
ELECTRONIC FUEL INJECTION
ELECTRONIC FUEL INJECTION
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,The
injected fuel quantity is directly proportional to
the switch-on time of the solenoid valve and
independent of the engine/pump speed (pure
time control of the injection quantity).
ELECTRONIC FUEL INJECTION
SUMMARY
Electronic Throttle— Drive-By-Wire
GDI—— Gasoline Direct Injection
Diesel Common Rail Injection System
HOMEWORK
List the advantages of the Drive-By-Wire
List the advantages of the Gasoline Direct Injection
ELECTRONIC FUEL INJECTION
