BRAKE SYSTEM HAVING SIMULTANEOUS OR PARTIALLY SIMULTANEOUS PRESSURE GENERATION AND REDUCTION IN THE WHEEL BRAKES FROM DIFFERING WHEEL CYLINDER PRESSURE LEVELS

摘要

The invention relates to a braking system with a brake booster, the piston-cylinder system (14, HZ, THZ) of which is driven by an electric motor, wherein at least one working chamber of the piston-cylinder system (14, HZ, THZ) is connected by hydraulic lines to at least two wheel brakes, a wheel brake being allocated a 2/2-way switching valve (17a, 17b, 17c, 17d) in each case and the hydraulic connection lines between the wheel brakes (18a, 18b, 18c, 18d) and the piston-cylinder system (14, HZ) being closable, optionally separately or jointly, by means of the 2/2-way switching valves (17a, 17b, 17c, 17d), so that a pressure can be adjusted in the wheel brakes (18a, 18b, 18c, 18d) one after the other in terms of a multiplex method and/or simultaneously, the electric motor and switching valves (17a, 17b, 17c, 17d) being activated by a control device, and in that the hydraulic connection line from the working chamber of the piston-cylinder system (14, HZ, THZ) to the respective magnetic valve has a flow resistance RLi and each switching valve together with the hydraulic line to the wheel cylinder (17a, 17b, 17c, 17d) has a flow resistance RVi, wherein the flow resistances RLi and RVi are small such that the HZ piston speed determines the pressure reduction gradient and pressure generation gradient in each wheel brake (18a, 18b, 18c, 18d), the flow resistance RLi being smaller than the flow resistance RVi, and in that the control device adjusts or controls the piston movement and piston speed during the pressure generation and pressure reduction as a function of the pressure-volume characteristic of the wheel brakes (18a, 18b, 18c, 18d). w Captions Fig. 2 and Fig. 3 Pab = Pred Pauf ~ Pgen Tum — Tswitch Fig. 4 Leitungsinduktivitat = line inductance Volumen am Rad = volume at the wheel Kapazitat der Radzylinder = capacity of the wheel und der Brerasleitung cylinders and the brake line Druck am Rad = pressure at the wheel Stomungswiderstand = flow resistance Kapazitat des Thz (bei = capacity of the Thz (with geschlossenen Ventilen) the valves closed) Fig. 5 Leitungslange MV zu = line length MV to wheel Radzylinder cylinder Adaption der = adaptation of the pressure Druckmodellparameter model parameters Druckmodellparameter = pressure model parameter Sensorik = sensor system Druckmodell = pressure model (wheel (Raddruckschatzung) pressure estimate) Oder = or Regler = controller Aktor = actuator Signale zur Bestimmung der = signals to determine the Prioritaten priorities Ansteuerung Motor = activation motor Elektronik = electronic system Drucksteuerung bzw, - = pressure control or regelung mit adjustment with subordinate untergeordneten Reglern controllers (for example (z.B. Positionsregelung position control etc.) usw.) soil = desired Priorisierung (Radauswahl, = prioritisation (wheel z.B. simultan) selection, for example simultaneous) Ansteuerung Radventile = activation wheel valves Radauswahl = wheel selection