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ABS anti-lock braking system

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					ABS anti-lock braking system
POLO ABS anti-lock braking system)
?
Before consumers buy a car, have regarded ABS (antilock braking system) as an
important indicator. As technology advances, present, most cars have ABS as standard.
But ABS awareness and proper use, a lot of drivers is not very clear, and even there
have been some misunderstanding on the ABS. Some drivers think that ABS is to
shorten the braking distance of the device in any vehicle equipped with ABS braking
distance road certainly is not equipped with ABS braking than the shorter distance,
and even some people mistakenly believe that snow and ice on roads in the braking
distance can and the braking distance on the asphalt pavement quite; there are some
drivers that if equipped with ABS, even in the rain or snow and ice at high speed
would not have vehicles out of control. ABS is not, as some have thought it would
greatly improve the physical properties of the limits of car. Strictly speaking, ABS
function mainly in the physical limits of the performance period to ensure that their
vehicle braking and stability control.
Application of ABS
ABS (Anti-lock Brake System) that "anti-lock braking system",
can effectively control the wheels keep turning the state, improve vehicle stability
during braking and road conditions, poor vehicle braking performance. ABS by
installing the drive shaft on the wheel or continuously to detect the wheel speed
sensor speed, calculated by the computer at the wheel slip ratio, slip ratio with the
ideal comparison to make increase or decrease the brake pressure, decisions, orders
and timely adjustment of the implementing agencies brake pressure to keep the wheel
in the ideal braking.
ABS for the first time in 1906 was granted a patent in 1936, Bosch registered a motor
vehicle wheels to prevent locking of the "mechanical" patents.
Early designs all have the same problem: too complex and easy for lead to failure, and
they operate too slowly. ABS 1947, the world's first system for the first
time used a B-47 bomber. Teldix in 1964 began to study the project, its research
quickly Bosch ABS all over. Two years, the first test vehicle has ABS braking
distances with reduced functionality. Turns steering and stability is guaranteed, but at
that time about 1,000 Ying Yong analog parts and the safety switch, which means that
the system known as ABS 1 electronic control unit of the reliability and durability
inadequate to satisfy the large-scale production requirements, the need to improve.
Bosch electronic engine management of the development process, technology, digital
technology and integrated circuits (ICs) for the arrival of the number of electronic
components down to 140.
ABS 1968, began to study applied to the car. Since 1975, the U.S. Federal Motor
Vehicle Safety Standard 121, paragraph by, many heavy-duty trucks and buses
equipped with ABS, brake system, but many technical problems and truck industry
opposition, withdrew in 1978, this standard. The same year, Bosch introduced the
world's first function of the ABS electronic control systems company, ABS
2 system this set as a matching profile to begin the installation and assembly in the
Mercedes - Benz S-class car, and then quickly with In the BMW 7 Series luxury sedan.
During this period, the U.S. ABS after further research and design work has decreased,
but European and Japanese manufacturers continue to develop well-ABS.
After 80 years of the 20th century, due to imports of U.S. cars equipped with ABS, the
U.S. car manufacturers on the U.S. auto market showed new interest in ABS. With the
rapid development of microelectronics technology and people to the strong demand of
automobile driving safety, ABS unit in the world automotive industry is further
widely used. In 1987 the United States about 3% of the vehicle is equipped with very
reliable ABS. In the ensuing time, developers focused on simplifying the system. In
1989, Bosch's engineers succeeded in a hybrid control unit directly
attached to the hydraulic module. So they do not need to connect the control unit and
hydraulic module, wiring harness, connectors need not, therefore significantly reduce
the overall weight of the ABS 2E.
Bosch engineers in 1993, using the new valve to create the ABS 5.0, and in later years
developed version 5.3 and 5.7. A new generation of ABS 8's main features
is again greatly reduced weight, reduced volume, increased memory, while adding
more features, such as electronic distribution of brake pressure, thus replacing the rear
axle brake pressure to reduce the mechanical institutions. Some auto industry analysts
predict that the year has been confirmed: 90 in the mid 20th century, the world market,
most of the cars and trucks will be equipped with ABS.
ABS function
The main function of ABS is to improve the vehicle's braking performance,
improve traffic safety, to prevent the wheels locking during braking (ie, stop rolling),
to ensure the driver can control the direction of the braking and prevent rear axle
sideslip. The working principle is: when the emergency brake, mounted on each
wheel to rely on the high sensitivity of the wheel speed sensor, Once a wheel from
locking the computer to immediately control the pressure regulator allows the wheel
brake slave cylinder pressure relief, so that the wheels restoration of rotation, to
prevent the wheels locking purposes. ABS is actually working process of
"locking - release - Locking - release" cycle of working process,
the vehicle is always rolling gaps in critical locking state, effectively overcome by the
wheels locking during emergency braking of vehicles produced deviation, and
preventing the occurrence of the body out of control and so on.
Types of ABS can be divided into two kinds of mechanical and electronic. ABS
simple mechanical structure, the main use of its own internal structure, a simple
adjustment to achieve the effect of braking force. The device works is simple, there is
no feedback sensors such as surface friction and the wheel speed signal, the data
entirely on pre-set to work, whether it is stagnant water pavement, icy roads or muddy
roads and good concrete pavement, it The work is the same. Strictly speaking, this
ABS can only be called "advanced braking system (Advanced Brake
System)". Currently, only some low-end domestic pickup and other
vehicles are still using mechanical ABS.
ABS only use mechanical components to the mechanical physical properties of the
action, while ABS is the use of electronic computers to analyze all the data to arrive at
the results of operations. By the electronic ABS wheel speed sensor, wiring harness,
computer, ABS hydraulic pump, lights and other component parts. Each wheel
according to the wheel speed sensor signal, the computer on each wheel by applying
different braking force, respectively, so as to achieve a scientific and rational
allocation of braking force results.
The first ABS system 2 system. The so-called two ABS system is to install the two
rear wheels on the car. As the two rear brake hydraulic lines and the common one of a
control valve, so called to do "single-channel control system."
This system is based on the two rear wheels in the state of adhesion to the smaller
wheel brake pressure selected, this is called "low-election
principle." In other words, the principle of low election ABS vehicles have
a rear wheel locking tendency, the system only to the two rear wheels at the same time
relief. Also, because there is no front wheel anti-lock function, and thus, two brake
system is difficult to achieve the best results.
With the development of related technologies, and later to a "three-channel
control system", the system is based on the two systems, the two front
wheels from the independent control of two separate pipelines. Although the rear or
only the "low selecting principle", but realized the emergency
brake when the rear axle steering function and prevent sideslip function, so this
Jitongjubei the main features of modern ABS. So far, there are vehicles on the market
using this three-channel ABS control system.
Currently, the most common equipment in the vehicle is four-sensor four-channel
ABS system, each wheel by an independent hydraulic piping and solenoid valve
control, can achieve independent control of individual wheels. This structure can
achieve good anti-lock function.

				
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