Patent ID: 6185498
Filing Date: 2001-02-06
Classification: B60T

Abstract:
An electronically controllable brake booster witha 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, withthe control valve arrangement, as a function of a current value 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, anda second pressure changing position in which the current is lower than the low value,characterised in that by means of suitable means during a controlupon each changeover of the control valve arrangement from the holding position into the first or the second pressure changing position, or upon each changeover from the first or the second pressure changing position into the holding position, the current value is sensed at which the respective changeover actually takes place, andthis sensed current value is utilised for the specification of one of the higher value and the lower value, respectively, of the currents defining the holding position for a future corresponding changeover of the control valve arrangement.