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The electronic brake force distribution system EBD

The electronic brake force distribution system EBD

The electronic brake force distribution system EBD is a continuation and improvement of the four-channel ABS system (anti-lock braking system). ABS prevents the wheels from locking when sudden braking, EBD helps to drive the machine constantly, and not just at the moment of impact on the brakes. The system strictly doses the braking force on all four wheels of the car, using information from sensor devices of the anti-lock system.

In the case of unexpected braking, when the motorist sharply presses on the brake pedal, the center of gravity of the vehicle is transferred forward, and the load on the rear two wheels decreases. The load on all wheels in this situation is the same, so if the car owner does not take care of the EBD – the rear of his car can be blocked. This is fraught with drifts on corners, loss of control – the car will heel under the influence of lateral forces. It is necessary to monitor braking forces and correctly distribute them, if the car often transports loads and passengers.

The history of the origin of the electronic system EBD

Since EBD is an “improvement” and “logical continuation” of ABS, the history of the origin of these electronic systems is the same. Soon, according to experts, the two systems will be ubiquitously integrated into a single complex. This design is already used on the “Citroen C4” and “Hyundai Grandeur”.

The problem of locking the wheels arose with the advent of the first vehicles – railway steam engines. Blocked rear wheels lead to an increase in the braking distance, a decrease in driving performance, the appearance of defects, etc. With immobilized wheel pairs, the cars often lurched to one side, descended from the rail. The problem was learned to solve by automatic adjustment of braking forces or “cargo auto-mode”.

During the same period, mechanical cable brakes were installed on passenger cars. They demanded great physical strength from the driver: the owner of the car hit the brake system, thereby blocking the rear wheels. A little has been remedied by the hydraulic vacuum braking system, but it is impossible to develop an efficient braking system without electronics. Only an electrical impulse can prevent the center of gravity from shifting in fractions of a second.

Important dates of the “brake system history”:

  • 1936 year. The brake system proposed by Bosch was ineffective.
  • 1964 year. The semiconductor system has firmly entered the automotive industry. German engineer Heinz Lieber suggested that the ABS system must be made electric.
  • 1970 year. Concern “Daimler-Benz” announced that the first effective electric brakes were created. After the invented innovation was only perfected and supplemented.
  • 1971 year. The problem of the wedging of the rear wheels is solved, but the question remains about locking the front of the car. Electronic components are still unreliable.

Basic principles of the EBD system

Any driver had to simultaneously travel around the obstacle, suddenly appeared on the way, and brake. Adjust the trajectory while it is quite difficult: if you press the brake harder than you need – the wheels will fail. And if you need to brake at a turn or on a slippery surface like ice, then one anti-lock system may not be enough. The action of the EBD system applies to each wheel separately.

The “expansion” of the anti-block braking system solves the following tasks:

  • Determines the level of slip on each wheel individually, and not on the two front wheels or the two rear wheels.
  • It distributes brake forces. This takes into account the slippery surface of the track.
  • It changes the brake fluid pressure.
  • Helps the car to not lose stability even with lateral forces.
  • Minimizes skidding of the car on the turn (during braking).

How does the ABS-based EBD system work?

The EBD system exists on the basis of ABS. It includes such components:

  • Sensors that send signals to the brake force distributor from the anti-lock system. Information about the rotation of each wheel is recorded individually.
  • Acceleration / deceleration sensor, which refers to ABS. It is mounted in the wheel hubs of the car.
  • Valves that are part of the pressure modulator.
  • The electronic unit which is common both for the braking system and for its “expansion”. He receives information about the speed of rotation of the wheels. Processes it. Activates only those valves of the brake system that are needed.
  • Hydraulic unit which is part of ABS. It changes the brake forces on the wheels and axles of the car distributes them correctly.
  • Indicator lamp, which warns of problems in the active (brake) security system. Independently to solve the problem is strictly not recommended to operate a defective vehicle – too.

If the car is transporting people / cargo, then a strong shift of the center of gravity to the front axle of the machine will not work even with sudden braking. In this case, the effort will be distributed more evenly.

Pros and cons of the brake force distribution system, its advantages and disadvantages

The main advantage of the electronic brake force distributor is the fact that it allows the driver to safely brake in case of any external factors. Without ABS, not everyone can safely unlock the wheels with one touch of the foot. EBD is triggered automatically, even long turns are not afraid of it.

The system is part of the “electronic intelligence” of the machine. Many of its processes are automated. Hundreds of specialists are working to ensure that the active security system, including the braking system, is improved every day. To date, the speed of the anti-lock system has increased tens of times, and weight and cost – have decreased. The first brake systems weighed up to seven kilograms, and the current ones – only one and a half kilograms. One example of such an improvement is EBD. A competently tuned system helps save about 20% of the braking distance and provides the ability to maneuver. Sometimes from a few meters on the uneven track depends on health, and even the life of the driver and his passengers.

The main disadvantages of ABS- EBD experts call these moments:

  • Incompatible braking force distribution system EBD and “winter” rubber. The stopping distance in this case increases. The same minus applies to those ABS systems without the “expansion” of EBD. All the advantages of studded rubber are reduced to zero – ABS and EBD do not allow spikes to function.
  • The anti-lock braking system can be inferior in performance to standard brakes on sand, ice or snow, on clay and on gravel, on a “bad” non-uniform road.
  • ABS may not work if the vehicle speed is below 10 km / h.
  • The EBD software can “not understand” and “get confused with data” if one wheel hits the asphalt, and the other – not the ice surface. The sensors will send incomprehensible, erratic signals to the electronic unit.
  • Some owners of the car with “ABS-EBD” note that more money has been spent on repairs – the brake fluid has to be changed more often.
  • Psychological factor. The driver believes that having a “smart braking system”, you can relax and do not follow the road. He loses vigilance, which is necessary with any security system – active and passive.

How much is the brake force distribution system popular with drivers and automakers?

“ABS-EBD” is help for newcomers, a guarantee of their safety on the road, their sense of confidence. That is why in modern cars the anti-lock system is built-in without fail. The owners of a used car should check the availability of this innovation on the day of purchase – you just need to press the brake signal. The system is activated and “responds” to weak, but perceptible shocks in the leg.

But buying a car with a “brake complex”, it is worth to test it on different surfaces – homogeneous and heterogeneous, and in different conditions. The speed should be constantly changed. This will give a clear understanding of how the machine, equipped with an electronic brake force distribution system, will behave.


Date: 10.10.18     Views: 132