Method for operating a braking system

A method for operating a hydraulic braking system (1) for motor vehicles having an electrically controllable pressure provision device (3), having a hydraulic cylinder and piston arrangement, the piston of which can be driven by means of an electric motor, a high-pressure accumulator (2), a hydraulic line (11) extending between the pressure provision device (3) and the high-pressure accumulator (2), an electrically controllable shutoff valve (4) arranged in the hydraulic line for establishing and interrupting a hydraulic connection between the pressure provision device and the high-pressure accumulator, wheel brakes (5, 6, 7, 8), which can be supplied with pressure medium via the hydraulic line by means of at least one of the pressure provision device (3) and the high-pressure accumulator (2), and an electronic control and regulating unit (9) for actuating the electrically controllable pressure provision device (3) and the electrically controllable shutoff valve (4) so as to regulate a hydraulic pressure which is provided by at least one of the pressure provision device (3) and the high-pressure accumulator (2), comprising the step of, if a pressure buildup in the hydraulic line is carried out by activating the pressure provision device (3), connecting the high-pressure accumulator (2) temporarily by at least partial opening of the shutoff valve (4),

• wherein the high-pressure accumulator (2) is connected after a predetermined time period (Δt) after a time (tonPPD) of activation of the pressure provision device (3).

A braking system (1) for motor vehicles, comprising:

• an electrically controllable pressure provision device (3), in the form of a hydraulic cylinder and piston arrangement, the piston of which can be driven by means of an electric motor,
• a high-pressure accumulator (2), which can be connected to the pressure provision device (3) via a hydraulic line (11), in which an electrically controllable shutoff valve (4) is arranged,
• wheel brakes (5, 6, 7, 8), which can be supplied with a pressure medium by means of at least one of the pressure provision device (3) and the high-pressure accumulator (2),
• an electronic control and regulating unit (9) for actuating the electrically controllable pressure provision device (3) and the electrically controllable shutoff valve (4) so as to regulate a hydraulic pressure which is provided by the pressure provision device (3) and the high-pressure accumulator (2),
• the electronic control and regulating unit (9) controlling the system to activate the pressure provision device when a pressure buildup in the hydraulic line is carried out and connecting, via the hydraulic line, the high pressure accumulator only temporarily during the pressure buildup by at least partial opening of the shutoff valve.