Braking a moving vehicle and its consequent deceleration and stop distance depend above all on the coefficient of grip between the road surface and the surface of the tire. To optimize braking and stability under critical weather conditions, electronic brake system management has been introduced also on vehicles of an industrial type, where these requirements are felt in a particular way, considering the loads that these vehicles transport.
General system description
This system, shown in FIGURE 1, has the purpose to avoid wheel-locking in all road surface conditions, reducing braking distances and ensuring the stability of the vehicle and driver's control. Using speed sensors (5), the system detects if the wheels tend to lock and releases the pressure from the braking circuit using the ABS solenoid valves (3). By applying the brakes in pulses, the braking forces are transmitted by the entire circumference of the tire. The braking system is still fully pneumatic (as in a traditional system) and the electronic control intervenes only to prevent wheel locking. If the driver brakes using additional braking systems, such as a retarder system, these will be disabled during ABS intervention.
The function of the ASR / TC is to prevent the driving wheels (axle) from slipping so as to prevent pointless stresses on the mechanical parts and therefore the loss of traction, as well as grip. The system triggers via the command sent by the control unit to the ASR solenoid valves (6), in the phases of acceleration and on road surfaces with poor grip, improving stability on bends, too, and reducing excessive wear (it is installed on request).
EBL (Electronic Brakes Limiter).
By comparing the speed of the rear axle/driving wheels with those of the front axle, the controller can measure the degree of skid, the speed and the deceleration of the vehicle. This allows the controller to calculate the minimum deceleration required to slow down the vehicle in the shortest time possible, while preventing the wheels from locking. This function is guaranteed by the presence of the pressure sensor (7) (together with other devices), located in the pneumatic circuit between the duplex valve and the rear axle. This component is used to provide the ABS controller with the value of the pneumatic pressure under braking at the rear axle.
Control unit location
The control unit of the ABS system is installed in the passenger compartment, precisely in the lower part of the dashboard on the passenger side, behind a plastic guard fixed with some screws to the dashboard assembly.
WARNING: The makes and distinguishing signs of the vehicle manufacturers included in this document are only provided to inform the reader about the potential suitability of the said TEXA products to be used for the vehicles of the above-mentioned manufacturers. References to makes and models contained in this document are to be considered only as a rough guide.