HIGH BRAKING EFFICIENCY ANTI-LOCK BRAKE SYSTEM

SYSTEME DE FREINAGE ANTIBLOCAGE A EFFICACITE DE FREINAGE ELEVEE

English Abstract

This invention pertains generally to braking system for the
vehicle. The High Braking Efficiency Anti-Lock Brake System
(HBE-ABS) is composed by wheel speed sensors(2), vehicle body
acceleration sensors(1), brake pressure bleeding value(4), and
Electronic Control Unit (3) ---ECU.
Its main feature is that the electronic control unit (3) monitors
the body deceleration through the body acceleration sensors (1).
When the body deceleration value is not increased, the ECU (3)
starts to send pulse to bleed the more brake pressure to decrease
the slip to get maximum brake efficiency. The pulse width is
decided by the difference between the wheel deceleration and
body deceleration. The wider the pulse is, the more the pressure
will be bled. The body acceleration sensors provide the
acceleration for the X and Y axis to ECU (3) to maintain the same
track as before, and prevent the wheel over spinning.

Claims

Page 1
High Braking Efficiency Anti-Lock Brake System
CLAIMS ARE DEFINED AS FOLLOWS
1. The invention pertains generally to braking system for the
vehicle. The High Braking Efficiency Anti-Lock Brake
System (HBE-ABS) is composed by wheel speed
sensors(2), vehicle body acceleration sensors(1), brake
pressure bleeding value(4), and Electronic Control Unit
(ECU)(3). By definition, when the acceleration value is
negative, it is called as deceleration. Its main feature is that
the ECU(3) monitors the body and wheel deceleration
through wheel speed sensors (2), and vehicle body
acceleration sensors(1). When the vehicle body or wheel
deceleration value increases at the threshold, and then if
the body deceleration value reaches peak or decreases,
the ECU starts to send pulse to bleed the more brake
pressure to decrease the slip to get maximum brake
efficiency. After bleeding the brake pressure, if the body
deceleration decreases, ECU (3) stops sending pulse to
quit bleeding the brake pressure.
2. The body acceleration sensors (1) provide the acceleration
for the X and Y axis to ECU to maintain its track, and
prevent the wheel over spinning.
3. The pulse width is decided by the difference between the
wheel deceleration and body deceleration. The wider the
pulse is, the more the pressure will be bled.
4. For a small vehicle, if one acceleration sensor (1) is used
per vehicle, the body accelerations near every wheel (5)
are calculated by the wheel location, acceleration sensor
location, and center of gravity of the vehicle. For big
vehicle, the body acceleration sensors are installed near
the wheel (5).

Page 2
5. The signal from the body acceleration sensor(1) is filtered
by the digital signal processing controller on ECU (3) to get
ride of the vibration noise.
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Description

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High Braking Efficiency Anti-Lock Brake System
DESCRIPTION
Field of the invention
Ref to figure one, the invention pertains generally to braking system for
the vehicle. The High Braking Efficiency Anti-Lock Brake System (HBE-ABS)
is composed by wheel speed sensors(2), vehicle body acceleration
sensors(1), brake pressure bleeding value(4), and electronic control unit
(ECU)(3).
Background information and prior art
The current Anti-Lock Brake System (ABS) assumes that the maximum
coefficient of the friction vs slip rate is the same for all kinds of the
ground
surface. The slip rate is defined as the distance difference between the
vehicle body and the wheel to the distance of the body. All the current design
is based on the assumption. But in reality, that is not true. Especially on
ice or
snow, ABS tends to increase braking distances. This invention is designed to
solve the problem, and to maintain maximum braking efficiency.
Advantage and disadvantage
Compared with the current system, this invention gives the vehicle high
braking efficiency. It will decrease the braking distance on all kind of the
ground surface. It also maintains the vehicle track and increases safety and
saves lives.
Its disadvantage is the cost. Since vehicle body acceleration sensors(1) are
used, it will cost more.
Application
High Braking Efficiency Anti-Lock Brake System can be used on the vehicle
such as the car, truck and bus for high braking efficiency.

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Detail Description
Ref to figure one , the High Braking Efficiency Anti-Lock Brake System is
composed by wheel speed sensors(2), vehicle body acceleration sensors(1),
brake pressure bleeding control value(4), and electronic control unit (ECU)
(3).
On the body of the vehicle, the body acceleration sensors(1) are installed
to measure the acceleration of the body. For small vehicle, only one sensor is
used, the equivalent acceleration on the body near the wheel is calculated
based on the location of the center of gravity of the vehicle body, the
location
of the body sensor and the location of the wheels. For bigger vehicle, the
acceleration for different section of body can be different, to increase the
accuracy of the acceleration near the wheel, more acceleration body sensors
are installed. They are installed on the vehicle body near the wheels.
The wheel speed sensors (2) are the same as the sensors used currently.
It outputs the pulse. Then the frequency represents the wheel speed. The
wheel acceleration is calculated from the wheel speed by the electronic
control unit (3).
The electronic control unit (3) will get the body acceleration value near the
wheels and calculate the body equivalent acceleration from the body
acceleration sensors(1). The calculation is based on the body acceleration
sensor location, the wheel location and the location of the center of the
gravity.
For the bigger vehicle body, the acceleration value for individual wheel is
gotten directly from the individually section of the body sensor (1) which is
located near the wheel. After the body acceleration at the location of the
center of gravity needs to be calculated, it is regarded as equivalent
acceleration. When the equivalent acceleration or the acceleration of the
wheel reaches to threshold, the electronic control unit (3) records the body
acceleration and wheel acceleration. By definition, when the acceleration
value is negative, it is called as deceleration later. When the brake is
locked,
the slip is increased. The body deceleration value measured by the body
acceleration sensors will go through increasing, going to peak and then
decreasing. When the body deceleration reaches the peak or decreases, the
Electronic Control Unit sends pulse to the bleeding control valve to bleed the
more brake pressure. The wheel will speed up to decrease the slip rate.
According to the famous curve between brake efficiency and slip rate, the
braking efficiency increases until reaching the peak efficiency.
The pulse width is depended on the deceleration difference between body
sensors and the wheels sensors. The electronic control unit continues
monitoring the body sensors and wheel sensors. The pulse width is modified

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according to the difference between body sensor(1) value and wheel
sensor(2) value. When the brake pressure continues decrease, the wheel
speed up, the slip is decrease. According to the famous curve between brake
efficiency and slip rate. The brake efficiency will increase and maintain the
maximum efficiency. But there is some limitation of the bleeding, if brake
pressure bleeds too much, the deceleration will start to decrease, so the ECU
will monitor the deceleration to start to decrease. If the deceleration
decreased, the ECU stops the pulse to the bleeding value. There is other
case, like the ice surface, the more slip rate, the more decelerations is.
According to the control scheme above, the bleeding value will not bleed the
pressure. But the ECU will maintain the minimum wheel speed for steering by
bleeding the pressure. There is one more case, if the driver releases the
brake pedal or decreases to stop completely, the ECU continues monitor both
body and wheel deceleration, if deceleration value is decreased, the ECU also
stops sending pulse to quit bleeding pressure and prepare the next cycle.
The ABS brake bleeding controlling value(4) is controlled by the pulse
width from ECU (3), if the pulse width increase, more pressure will be bleed.
The controlling value (4) is the same as the current used one.
From above, the braking efficiency reaches to the maximum regardless of
the ground condition like pavement, ice, and snow surface.
The body acceleration sensor(1) is two-axis acceleration sensor. It
provides two-axis acceleration for the X and Y axis. The ECU will equalize the
brake pressure to the individual wheel to prevent the front or back wheel out
of track, and to prevent the wheel over spinning.
The Electrical Controlling Unit(ECU) is composed by Digital Signal
Processor controller, voltage converter and bleeding value current driver. The
controller main function is filtering the noise for the body acceleration
sensor,
calculating the acceleration/deceleration of the body and wheel acceleration,
and providing the pulse width to control the bleeding value.
Component assembly
For small vehicle, one body sensor (1) is required at least; the sensor is
installed in the ECU. The wheel sensors(2) are on the wheels. The wheels

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sensors are connected with the ECU. The ECU is connected with the ABS
controlling value. The orientation of the ECU (3) is required to align with
the
vehicle.
For bigger vehicle, more body acceleration sensors (1) are required; the
body acceleration sensors(1) are installed in the cable for the wheel
sensors(2). The orientation for sensors(1) must be the same as the vehicle
orientation.

Representative Drawing