6.1.12. Management of emergency brake application
At emergency brake application the DSC HU/CM block increases pressure of brake fluid by increase in pressure in the main cylinder therefore the big brake effort is reached by smaller pressing a brake pedal.
The DSC HU/CM system uses the built-in sensor of pressure of brake fluid for control of speed of change of pressure in the main cylinder, the amplifier of emergency brake application turns on when the speed of change of pressure exceeds a preset value, thus the system defines conditions of emergency brake application.
The DSC HU/CM system calculates pressure in the cylinder of the brake mechanism, increases liquid pressure in the main cylinder to a preset value. Thanks to change of pressure in the main cylinder, pressure in the cylinder of the brake mechanism can be increased.
In addition to the normal pressure of brake fluid as all electromagnetic valves are switched on, the electric motor puts the pump which increases pressure in the brake system in action.
Fig. 6.7. Scheme of management of emergency brake application of the Mazda 3 car: 1 – normal mode of braking; 2 – the braking mode without amplifier of emergency brake application; 3 – main cylinder; 4 – electromagnetic valve of maintenance of stability; 5 – electromagnetic valve of maintenance of pressure; 6 – electromagnetic valve of pressure decrease; 7 – pump electric motor; 8 – electromagnetic valve of the switch of draft; 9 – pump; 10 – support piston
The amplifier of emergency brake application begins to work at speeds of 17 km/h or above and does not turn on at speeds less than 5 km/h.