Electronic braking system
The electronic brake system (EBS) is a further development of the compressed air brake system . The electronic components achieve a shorter brake response time.
For some years now, EBS has been the preferred choice for trucks with a gross vehicle weight of 7.5 t or more and buses and coaches . These are mostly three-channel or four-channel systems in which the brake pressure of the individual axles can be regulated independently of one another. Legal approval is based on the ECE-R13 directive. The basic function consists of the electronic service brake, whereby the brake cylinder pressure of the disc or drum brake is regulated individually for each channel, depending on several factors. In addition, ABS or ESC and ASR and other functions are also integrated. Also the coupling head pressure for theTrailer is controlled electronically, with an electronic interface installed in parallel so that even modern trailers, which themselves have an EBS, can be optimally controlled.
The systems have a pneumatic fallback level, which is activated in the event of an electrical fault and then enables conventional, pneumatically controlled braking. This fallback system has two circuits and also serves any trailer that may be present, so that all wheels can be braked even in the event of a fault.
The EBS is embedded in an electronic network that enables information to be exchanged between all vehicle systems such as engine , transmission and retarder via a data network (mostly CAN ) .
function
Braking takes place via the so-called foot brake module, which is activated by the driver via the brake pedal. The electrical signal generated in the process is passed on to the control unit. This calculates the optimum brake pressure for each axle from the information available in the data network. This information is forwarded to the proportional valve on the front axle and to the rear axle modulator , which then control the desired brake cylinder pressures. The trailer control module also receives information from the control unit and modulates a corresponding pressure on the trailer coupling head . At the same time, an adequate CAN signal is output at the ISO 7638 trailer socket, which can be evaluated by any trailer EBS.
advantages
EBS enables an improved response behavior of the brakes and thus a shorter braking distance. The integration of the permanent brakes ( engine brake , retarder) in the service braking process keeps the pads cool and thereby improves the fading and downtime behavior . The integrated coupling force control enables braking force harmonization between the towing vehicle and trailer. The pad wear control harmonizes the pad wear between the front and rear axle (s). A hill holder function, ESP and distance-controlled cruise control are optionally available. The electronic integration of all individual components enables a quick and targeted diagnosis.
EBS has established itself on the market and is offered in series by all well-known commercial vehicle manufacturers.