Electronically controllable brake booster

Abstract

The invention relates to an electronically controllable brake booster with a vacuum chamber and a pressure chamber, which are separated from each other by a movable wall, a control valve arrangement which can be actuated by means of an electromagnetic actuation means, and by means of which a pressure difference between the pressure chamber and the vacuum chamber can be adjusted, with the control valve arrangement, as a function of a current flowing through the electromagnetic actuation means, assuming a holding position in which the current ranges between a higher value and a lower value without the control valve arrangement leaving the holding position, a first pressure changing position in which the current is higher than the higher value, and a second pressure changing position in which the current is lower than the low value, characterized in that upon a changeover of the control valve arrangement from the holding position into the first or the second pressure changing position, or upon a changeover from the first or the second pressure changing position into the holding position, the time period is determined which is required for the changeover, the determined time period is compared with a predetermined time interval in order to determine whether the changeover has taken place within this predetermined time interval, and the higher and/or lower current value defining the holding position is modified for future changeovers if the determined time period exceeds the predetermined time interval.