UNIT10
BRAKING SYSTEMS
TEXT B
Traction Control System (TRAC)
and Electronic Stability Control (ESC)
PROFESSIONAL ENGLISH
UNIT 3
BRAKING SYSTEMS
TEXT B
Traction Control System (TRAC)
and Electronic Stability Control (ESC)
Traction Control System (TRAC)
Components
TRAC Operation
Intake Electronic Stability Control (ESC)
What Is Electronic Stability Control?
How ESC Works
Many Names
本次课学习内容本次课学习目标
掌握 TRAC和 ESC系统的有关属术语
掌握 TRAC和 ESC系统的组成和原理
提高翻译技巧与阅读能力
NEW WORDS
coefficient [k?ui'fi∫?nt] n.系数
gravel ['gr? v?l] n.砂砾,砂砾层
console [k?n's?ul] n.控制台
deactivate [di:'? ktiveit] v.解除,使无效,使不活动
slippage ['slipid? ] n.滑动,滑移
alleviate [?'li:vieit] v.减轻
headline ['hedlain] n.大字标题
rollover ['r?uluv?] n.倾翻
intervene [?int?'vi:n] v.干涉,干预,插入,介入
oversteer(ing) ['?uv?sti?(ri?)] n,过度转向
understeer(ing) ['?nd?sti?(ri?)] n,不足转向
hail [heil] v,& n.招呼,欢呼,高呼
yaw-rate ['j?:'reit] n.横摆速率
default [di'f?:lt] n,& v.默认 (值 )
PHRASES AND EXPRESSIONS
traction control
system(TCS)
牵引控制系统（ TCS）
sub-throttle plate 副节气门
center console 中央控制台
TRAC brake actuator TRAC制动执行器
master cylinder cut
solenoid valve
主缸切断电磁阀，主缸隔离电磁阀
pressure regulator
valve
调压电磁阀
electronic stability
control (ESC)
电子稳定性控制（ ESC）
make the headlines 成为头条新闻
make a difference 发生影响，起作用，区别对待
active safety system 主动安全系统
Traction Control System (TRAC)
and Electronic Stability Control (ESC)
Traction Control System (TRAC)
The purpose of the traction control system (TCS,or TRAC)
(Fig.10-3) is to prevent wheel spin from occurring due to
acceleration,The maximum torque that can be transmitted to
the wheels is determined by the coefficient of friction
generated between the road and the tires,If torque exceeds
that level,the wheels are likely to spin,Conditions for TRAC
operation may include,loose gravel,slippery road surfaces,
acceleration while cornering and hard acceleration [1].
Once activated,the TRAC System reduces engine torque
and rear wheel speed as necessary to bring the vehicle under
control,The ABS ECU,TRAC ECU and ECM all work together
to provide traction control,ABS speed sensors are monitored
by the TRAC ECU which in turn controls a sub-throttle plate
and applies the rear brakes,The ECM also retards engine
timing while the ABS modulates pressure at the rear brakes.
Fig,10-3 TRAC system components
Components
The TRAC OFF switch is located on the instrument panel
above the center console,It allows the driver to activate or
deactivate the TRAC system when the switch is depressed,The
system defaults to ON when the ignition switch is cycled.
The TRAC OFF indicator light goes on when anyone of the
following occur:
·the TRAC system is deactivated by the TRAC OFF switch.
·a TRAC related problem is detected with the engine.
·an ABS related problem is detected,
The TRAC indicator light indicates when:
·the system is operating.
·a malfunction occurs in the system (it remains illuminated to
warn the driver).
·the diagnostic mode is set within the TRAC ECU (the light
blinks the trouble code).
Sub-Throttle Valve Motor
The sub-throttle actuator uses a step motor located between
the main throttle valve and air cleaner,It is fitted on the throttle
body and controls the position of the sub-throttle valve based on
commands made by the TRAC ECU thus controlling the engine
output,By controlling the sub-throttle plate,engine management
controls engine torque reducing wheel spin.
Sub-Throttle Position Sensor
This sensor is fitted to the sub-throttle valve shaft,It converts
the sub-throttle valve opening angle to a voltage signal and sends
this signal to the TRAC ECU via the ECM (Engine ECU),The sensor
operates in the same way as the main throttle position sensor.
TRAC Pump
The function of the TRAC Pump is to generate brake fluid
pressure necessary for applying the rear disc brakes when the
TRAC system is operating,It draws brake fluid from the master
cylinder reservoir,pressurizes and directs it to the TRAC brake
actuator,
Fig.10-4 Sub-throttle valve motor
TRAC Brake Actuator
The TRAC brake actuator consists of two cut solenoid valves
and three spring loaded valves which regulate the brake fluid
pressure in the right and left rear wheels,The rear wheels are
controlled independently through the ABS actuator based on
signals from the ABS ECU.
The master cylinder cut solenoid valve opens and closes the
hydraulic circuit from the master cylinder or TRAC pump to the ABS
actuator,When the TRAC system is operating,it supplies the brake
fluid pressure from the TRAC pump to the disc brake cylinders via
the ABS actuator,It also prevents the fluid from flowing out of the
ABS actuator pump to the master cylinder.
The reservoir cut solenoid valve is located between the return
side of the ABS 3-position solenoid and the master cylinder,It
returns the fluid from the disc brake cylinders back to the master
cylinder reservoir.
The pressure regulator valve controls the brake fluid pressure
generated by the TRAC pump.
The relief valve relieves the systems highest pressure
should a malfunction occur [2].
The check valve prevents fluid from flowing out of the
disc brake cylinder to the TRAC pump.
TRAC Operation
During normal operation (TRAC not activated) all
solenoid valves of the TRAC brake actuator remain inactive
when the brakes are applied,As the brake pedal is
depressed,brake fluid pressure generated by the master
cylinder is applied to the disc brake cylinders,via the master
cylinder cut solenoid valve,and the 3-position solenoid
valves in the ABS actuator,When the brake pedal is released,
fluid pressure returns from the disc brake cylinders to the
master cylinder.
During vehicle acceleration (TRAC operative) when a rear
wheel slips the TRAC system controls the engine output and
braking of the rear wheels to help prevent wheel slippage.
The brake fluid pressure applied to the right and left rear
wheels is controlled separately according to 3 control modes,
pressure increase,pressure holding and pressure reduction,
Pressure Increase Mode
When a rear wheel starts to slip,just as the accelerator
pedal is being depressed:
·All the solenoid valves in the TRAC brake actuator are
activated by signals received from the ABS ECU.
·The 3-position solenoid valves in the ABS actuator are
engaged in the pressure increase mode(Fig.10-5).
·The master cylinder cut solenoid valve is activated (ports
"A" and "C" open),and brake fluid pressure generated by the
TRAC pump is applied to the disc brake cylinders via the
master cylinder cut solenoid valve and the 3-position solenoid
valves in the ABS actuator.
·The reservoir cut solenoid valve is also activated (open)
allowing fluid to flow back to the master cylinder reservoir.
·The TRAC pump discharge pressure is maintained
constant by the pressure regulator valve.
Fig.10-5 Pressure increase mode
Pressure Holding Mode
When the brake fluid pressure for the rear brake
cylinders is increased or decreased as required,the system
switches to the holding mode,This mode change is
performed by engaging the 3-position solenoid valve in the
ABS actuator to the holding mode,This results in blocking
the TRAC pump pressure from flowing to the disc brake
cylinder through port D.
Pressure Reduction Mode
When decreasing pressure applied to the rear brake
cylinders,the ABS ECU engages the 3-position solenoid
valve in the ABS actuator to the pressure reduction mode,
Fluid pressure applied to the brake cylinder returns to the
master cylinder reservoir from the 3-position solenoid valve
and reservoir in the ABS actuator to the reservoir cut
solenoid valve,thus alleviating the brake fluid pressure.
Wheel Speed Control
The TRAC ECU constantly receives signals from the 4
speed sensors and calculates the speed of each wheel,At
the same time,it estimates the vehicle speed based on the
speed of the 2 front wheels and sets a target control speed.
When the accelerator pedal is depressed on a slippery road,
the rear wheels (driving wheels) begin to slip and the rear
wheel speed exceeds the target control speed,The TRAC
ECU then sends a close signal to the sub-throttle valve
motor.
At the same time,ABS ECU sends a signal to the TRAC
brake actuator and causes it to supply brake fluid pressure
to rear disc brake cylinders,changing the rear disc brakes
in the TRAC mode,The 3-position solenoid valves of the
ABS actuator are modulated to control rear brake fluid
pressure to prevent wheel slippage.
Electronic Stability Control (ESC)
Automotive safety has taken center stage,especially as
SUVs have made the headlines for their tendency to
rollover,For today's consumers,however,electronic
stability control (ESC) can make a difference,ESC can
significantly reduce the risk of an SUV rollover,
What Is Electronic Stability Control?
ESC is an active safety system that uses sensors to detect
when a driver is about to lose control of the vehicle and
automatically intervenes to provide stability and help the
driver stay on the intended course,especially in
oversteering and understeering situations,Industry experts
have hailed electronic stability control as a milestone in
automotive safety,comparing it to seatbelts and airbags,
ESC keeps vehicles on the road,helps prevent rollovers and
skids,and is thus the easy safety choice for consumers
when purchasing a new vehicle,
A number of studies have been conducted testing the
effectiveness of ESC,and the global auto safety research
verifies that electronic stability control does,in fact,save lives,
Five different studies projected a 30-35% reduction in single
vehicle crashes thanks to ESC,
How ESC Works
It incorporates anti-lock brakes (ABS) and traction control
(TCS),which prevent wheel lock when braking and wheel spin
when accelerating,and goes a step beyond both systems,
acting when lateral forces are at work to further reduce the risk
of skidding in all driving situations,
ESC constantly compares the driver’s intention with the
vehicle’s actual behavior by monitoring wheel speeds,steering
wheel angle,yaw-rate,lateral acceleration,throttle position
and master cylinder pressure.
A central microcomputer analyzes the incoming data,When
instability is detected,ESC immediately triggers a response to
keep the vehicle on course,automatically braking any of the
four wheels and/or adjusting engine torque,
ESC is offered as optional or standard equipment in a wide
variety of vehicles from nearly every automaker,It is a safety
feature that goes by many names,
·Electronic Stability Program – ESP (Audi,Mercedes,
Saab,VW)
·Dynamic Stability Control – DSC (BMW,Land Rover,
Jaguar)
·StabiliTrak (Buick,Cadillac,Chevrolet,GMC,Pontiac)
·AdvanceTrac (Ford,Lincoln,Mercury)
·Vehicle Dynamics Control – VDC (Subaru,Nissan,
Infiniti)
·Vehicle Stability/Skid Control – VSC (Toyota,Lexus)
·Vehicle Stability Assist – VSA (Acura)
·Precision Control System (Oldsmobile)
·Dynamic Stability Traction Control – DSTC (Volvo)
·Stability Management System (Porsche)
·Active Handling (Chevrolet Corvette)
Despite the proven effectiveness of Electronic Stability
Control,only 6% of all vehicles manufactured in the U.S,
are equipped with it,compared to more than 30% in
Europe,
小结
Traction Control System (TRAC)
Components
TRAC Operation
Pressure Increase Mode
Pressure Holding Mode
Pressure Reduction Mode
Wheel Speed Control
Intake Electronic Stability Control (ESC)
What Is Electronic Stability Control?
How ESC Works
Many Names
作业
熟记相关专业词汇
P231 EXERCIES Ⅰ & Ⅱ
BRAKING SYSTEMS
TEXT B
Traction Control System (TRAC)
and Electronic Stability Control (ESC)
PROFESSIONAL ENGLISH
UNIT 3
BRAKING SYSTEMS
TEXT B
Traction Control System (TRAC)
and Electronic Stability Control (ESC)
Traction Control System (TRAC)
Components
TRAC Operation
Intake Electronic Stability Control (ESC)
What Is Electronic Stability Control?
How ESC Works
Many Names
本次课学习内容本次课学习目标
掌握 TRAC和 ESC系统的有关属术语
掌握 TRAC和 ESC系统的组成和原理
提高翻译技巧与阅读能力
NEW WORDS
coefficient [k?ui'fi∫?nt] n.系数
gravel ['gr? v?l] n.砂砾,砂砾层
console [k?n's?ul] n.控制台
deactivate [di:'? ktiveit] v.解除,使无效,使不活动
slippage ['slipid? ] n.滑动,滑移
alleviate [?'li:vieit] v.减轻
headline ['hedlain] n.大字标题
rollover ['r?uluv?] n.倾翻
intervene [?int?'vi:n] v.干涉,干预,插入,介入
oversteer(ing) ['?uv?sti?(ri?)] n,过度转向
understeer(ing) ['?nd?sti?(ri?)] n,不足转向
hail [heil] v,& n.招呼,欢呼,高呼
yaw-rate ['j?:'reit] n.横摆速率
default [di'f?:lt] n,& v.默认 (值 )
PHRASES AND EXPRESSIONS
traction control
system(TCS)
牵引控制系统（ TCS）
sub-throttle plate 副节气门
center console 中央控制台
TRAC brake actuator TRAC制动执行器
master cylinder cut
solenoid valve
主缸切断电磁阀，主缸隔离电磁阀
pressure regulator
valve
调压电磁阀
electronic stability
control (ESC)
电子稳定性控制（ ESC）
make the headlines 成为头条新闻
make a difference 发生影响，起作用，区别对待
active safety system 主动安全系统
Traction Control System (TRAC)
and Electronic Stability Control (ESC)
Traction Control System (TRAC)
The purpose of the traction control system (TCS,or TRAC)
(Fig.10-3) is to prevent wheel spin from occurring due to
acceleration,The maximum torque that can be transmitted to
the wheels is determined by the coefficient of friction
generated between the road and the tires,If torque exceeds
that level,the wheels are likely to spin,Conditions for TRAC
operation may include,loose gravel,slippery road surfaces,
acceleration while cornering and hard acceleration [1].
Once activated,the TRAC System reduces engine torque
and rear wheel speed as necessary to bring the vehicle under
control,The ABS ECU,TRAC ECU and ECM all work together
to provide traction control,ABS speed sensors are monitored
by the TRAC ECU which in turn controls a sub-throttle plate
and applies the rear brakes,The ECM also retards engine
timing while the ABS modulates pressure at the rear brakes.
Fig,10-3 TRAC system components
Components
The TRAC OFF switch is located on the instrument panel
above the center console,It allows the driver to activate or
deactivate the TRAC system when the switch is depressed,The
system defaults to ON when the ignition switch is cycled.
The TRAC OFF indicator light goes on when anyone of the
following occur:
·the TRAC system is deactivated by the TRAC OFF switch.
·a TRAC related problem is detected with the engine.
·an ABS related problem is detected,
The TRAC indicator light indicates when:
·the system is operating.
·a malfunction occurs in the system (it remains illuminated to
warn the driver).
·the diagnostic mode is set within the TRAC ECU (the light
blinks the trouble code).
Sub-Throttle Valve Motor
The sub-throttle actuator uses a step motor located between
the main throttle valve and air cleaner,It is fitted on the throttle
body and controls the position of the sub-throttle valve based on
commands made by the TRAC ECU thus controlling the engine
output,By controlling the sub-throttle plate,engine management
controls engine torque reducing wheel spin.
Sub-Throttle Position Sensor
This sensor is fitted to the sub-throttle valve shaft,It converts
the sub-throttle valve opening angle to a voltage signal and sends
this signal to the TRAC ECU via the ECM (Engine ECU),The sensor
operates in the same way as the main throttle position sensor.
TRAC Pump
The function of the TRAC Pump is to generate brake fluid
pressure necessary for applying the rear disc brakes when the
TRAC system is operating,It draws brake fluid from the master
cylinder reservoir,pressurizes and directs it to the TRAC brake
actuator,
Fig.10-4 Sub-throttle valve motor
TRAC Brake Actuator
The TRAC brake actuator consists of two cut solenoid valves
and three spring loaded valves which regulate the brake fluid
pressure in the right and left rear wheels,The rear wheels are
controlled independently through the ABS actuator based on
signals from the ABS ECU.
The master cylinder cut solenoid valve opens and closes the
hydraulic circuit from the master cylinder or TRAC pump to the ABS
actuator,When the TRAC system is operating,it supplies the brake
fluid pressure from the TRAC pump to the disc brake cylinders via
the ABS actuator,It also prevents the fluid from flowing out of the
ABS actuator pump to the master cylinder.
The reservoir cut solenoid valve is located between the return
side of the ABS 3-position solenoid and the master cylinder,It
returns the fluid from the disc brake cylinders back to the master
cylinder reservoir.
The pressure regulator valve controls the brake fluid pressure
generated by the TRAC pump.
The relief valve relieves the systems highest pressure
should a malfunction occur [2].
The check valve prevents fluid from flowing out of the
disc brake cylinder to the TRAC pump.
TRAC Operation
During normal operation (TRAC not activated) all
solenoid valves of the TRAC brake actuator remain inactive
when the brakes are applied,As the brake pedal is
depressed,brake fluid pressure generated by the master
cylinder is applied to the disc brake cylinders,via the master
cylinder cut solenoid valve,and the 3-position solenoid
valves in the ABS actuator,When the brake pedal is released,
fluid pressure returns from the disc brake cylinders to the
master cylinder.
During vehicle acceleration (TRAC operative) when a rear
wheel slips the TRAC system controls the engine output and
braking of the rear wheels to help prevent wheel slippage.
The brake fluid pressure applied to the right and left rear
wheels is controlled separately according to 3 control modes,
pressure increase,pressure holding and pressure reduction,
Pressure Increase Mode
When a rear wheel starts to slip,just as the accelerator
pedal is being depressed:
·All the solenoid valves in the TRAC brake actuator are
activated by signals received from the ABS ECU.
·The 3-position solenoid valves in the ABS actuator are
engaged in the pressure increase mode(Fig.10-5).
·The master cylinder cut solenoid valve is activated (ports
"A" and "C" open),and brake fluid pressure generated by the
TRAC pump is applied to the disc brake cylinders via the
master cylinder cut solenoid valve and the 3-position solenoid
valves in the ABS actuator.
·The reservoir cut solenoid valve is also activated (open)
allowing fluid to flow back to the master cylinder reservoir.
·The TRAC pump discharge pressure is maintained
constant by the pressure regulator valve.
Fig.10-5 Pressure increase mode
Pressure Holding Mode
When the brake fluid pressure for the rear brake
cylinders is increased or decreased as required,the system
switches to the holding mode,This mode change is
performed by engaging the 3-position solenoid valve in the
ABS actuator to the holding mode,This results in blocking
the TRAC pump pressure from flowing to the disc brake
cylinder through port D.
Pressure Reduction Mode
When decreasing pressure applied to the rear brake
cylinders,the ABS ECU engages the 3-position solenoid
valve in the ABS actuator to the pressure reduction mode,
Fluid pressure applied to the brake cylinder returns to the
master cylinder reservoir from the 3-position solenoid valve
and reservoir in the ABS actuator to the reservoir cut
solenoid valve,thus alleviating the brake fluid pressure.
Wheel Speed Control
The TRAC ECU constantly receives signals from the 4
speed sensors and calculates the speed of each wheel,At
the same time,it estimates the vehicle speed based on the
speed of the 2 front wheels and sets a target control speed.
When the accelerator pedal is depressed on a slippery road,
the rear wheels (driving wheels) begin to slip and the rear
wheel speed exceeds the target control speed,The TRAC
ECU then sends a close signal to the sub-throttle valve
motor.
At the same time,ABS ECU sends a signal to the TRAC
brake actuator and causes it to supply brake fluid pressure
to rear disc brake cylinders,changing the rear disc brakes
in the TRAC mode,The 3-position solenoid valves of the
ABS actuator are modulated to control rear brake fluid
pressure to prevent wheel slippage.
Electronic Stability Control (ESC)
Automotive safety has taken center stage,especially as
SUVs have made the headlines for their tendency to
rollover,For today's consumers,however,electronic
stability control (ESC) can make a difference,ESC can
significantly reduce the risk of an SUV rollover,
What Is Electronic Stability Control?
ESC is an active safety system that uses sensors to detect
when a driver is about to lose control of the vehicle and
automatically intervenes to provide stability and help the
driver stay on the intended course,especially in
oversteering and understeering situations,Industry experts
have hailed electronic stability control as a milestone in
automotive safety,comparing it to seatbelts and airbags,
ESC keeps vehicles on the road,helps prevent rollovers and
skids,and is thus the easy safety choice for consumers
when purchasing a new vehicle,
A number of studies have been conducted testing the
effectiveness of ESC,and the global auto safety research
verifies that electronic stability control does,in fact,save lives,
Five different studies projected a 30-35% reduction in single
vehicle crashes thanks to ESC,
How ESC Works
It incorporates anti-lock brakes (ABS) and traction control
(TCS),which prevent wheel lock when braking and wheel spin
when accelerating,and goes a step beyond both systems,
acting when lateral forces are at work to further reduce the risk
of skidding in all driving situations,
ESC constantly compares the driver’s intention with the
vehicle’s actual behavior by monitoring wheel speeds,steering
wheel angle,yaw-rate,lateral acceleration,throttle position
and master cylinder pressure.
A central microcomputer analyzes the incoming data,When
instability is detected,ESC immediately triggers a response to
keep the vehicle on course,automatically braking any of the
four wheels and/or adjusting engine torque,
ESC is offered as optional or standard equipment in a wide
variety of vehicles from nearly every automaker,It is a safety
feature that goes by many names,
·Electronic Stability Program – ESP (Audi,Mercedes,
Saab,VW)
·Dynamic Stability Control – DSC (BMW,Land Rover,
Jaguar)
·StabiliTrak (Buick,Cadillac,Chevrolet,GMC,Pontiac)
·AdvanceTrac (Ford,Lincoln,Mercury)
·Vehicle Dynamics Control – VDC (Subaru,Nissan,
Infiniti)
·Vehicle Stability/Skid Control – VSC (Toyota,Lexus)
·Vehicle Stability Assist – VSA (Acura)
·Precision Control System (Oldsmobile)
·Dynamic Stability Traction Control – DSTC (Volvo)
·Stability Management System (Porsche)
·Active Handling (Chevrolet Corvette)
Despite the proven effectiveness of Electronic Stability
Control,only 6% of all vehicles manufactured in the U.S,
are equipped with it,compared to more than 30% in
Europe,
小结
Traction Control System (TRAC)
Components
TRAC Operation
Pressure Increase Mode
Pressure Holding Mode
Pressure Reduction Mode
Wheel Speed Control
Intake Electronic Stability Control (ESC)
What Is Electronic Stability Control?
How ESC Works
Many Names
作业
熟记相关专业词汇
P231 EXERCIES Ⅰ & Ⅱ
