Patent ID: 6209967
Filing Date: 2001-04-03
Classification: B60T

Abstract:
A pneumatic brake power booster for automotive vehicles, comprising:a booster housings with an interior which is subdivided by a movable wall into a first chamber and a second chamber,a control housing accommodating a control valve which controls a pneumatic pressure difference acting upon the movable wall, wherein the control valve includes at least two sealing seats that cooperate with a sealing surface of an elastic valve member, wherein one of said sealing seats is operable by an actuating rod, and wherein the remaining sealing seat is operable, irrespective of the position of the actuating rod, by an electromagnet with an armature that cooperates in a force-transmitting way with one of the sealing seats, wherein the elastic valve member confines a pneumatic chamber in the control housing, and includes through passages in the sealing surface of the valve member, and further wherein the through passages are located radially outside an area which is limited by the electromagnetically operable sealing seat on the sealing surface of the elastic valve member, whereby pressure compensation between the pneumatic chamber and the second chamber takes place at the elastic valve member.