EBD brake force distribution system
Automotive engineers have long established the fact that during braking, a large proportion of the load is transferred to the drive pair of wheels, while the rear wheels are often blocked precisely from lack of mass. In cases of emergency braking on ice or wet pavement, the car may begin to turn due to the difference in the degree of adhesion of each wheel to the roadway. That is, the characteristics of grip with the road are different, and the pressure of the brakes on each wheel is the same - this is what leads to the fact that the car begins to turn while driving. This effect is especially noticeable on a non-uniform road surface.
To avoid the occurrence of such an emergency, modern cars install a brake force distribution system - EBD. This system always works in tandem with the anti-lock braking system ABS and, in fact, is the result of an improvement in its functionality. The essence of EBD is that it ensures the safety of driving a vehicle in a stable mode, and not just at the moment when the driver sharply presses the brake pedal.
The brake force distribution system receives information from the ABS sensors and integrates the rotational speed of each of the four wheels, providing them with the necessary braking force. Thanks to the work of EBD, a different degree of braking pressure is applied to each wheel, which ensures the stabilization of the vehicle's position on the road. Thus, the EBD and ABS systems always work together.
The brake force distribution system is designed to perform several functions:
- preservation of the original trajectory of the vehicle;
- reducing the risk of skids, drifts or turns of the car during heavy braking on corners or ice;
- ensuring ease of driving in a constant mode.
EBD work cycle
Like ABS, the EBD system has a cyclical nature of operation. Cyclicity means the execution of three stages in a constant sequence:
- pressure is maintained in the brake system;
- the pressure is released to the required level;
- the pressure on all wheels increases again.
The first stage of work is carried out by the ABS unit. It collects readings from the wheel speed sensors and compares the effort with which the front and rear wheels rotate. In the event that the difference between the indicators of the forces performed during rotation between the front and rear pairs begin to exceed the set value, the brake force distribution system is included in the matter. The control unit closes the valves that work to inlet the brake fluid, in connection with this, the pressure on the rear wheels is kept at the level it was at the time the valves were closed.
At the same moment, the intake valves, which are located in the devices of the front wheels, do not close, that is, the pressure of the brake fluid on the front wheels increases. The system pressurizes the front pair of wheels until they are completely blocked.
In case this is not enough, then the EBD gives an impulse to open the valves of the rear pair of wheels, which work for exhaust. This quickly reduces the pressure on them and eliminates opportunities for blocking. That is, the rear wheels begin to brake just as effectively.
If you need to adjust existing settings
Almost all modern car models today are equipped with these active safety systems. There can be no dispute about the merits of EBD: increased controllability and elimination of the risk of skidding during emergency braking makes the EBD system one of the most popular in the automotive industry.
In some cases, additional adjustment of the system settings may be required, for example, in connection with the start of a new season in the operation of a car. It is not recommended to independently regulate complex electronic systems; it is more expedient to contact specialists. FAVORIT MOTORS Group of Companies offers the best combination of price and quality ratio of repair and restoration work, thanks to which the diagnosis and repair of EBD + ABS active safety systems will be performed competently and at a reasonable cost.
