Patent ID: 6367364
Filing Date: 2002-04-09
Classification: B60T

Abstract:
Brake force booster for automotive vehicles, comprising:a booster housing having an interior space subdivided by a movable wall into a vacuum chamber and a working chamber, a control valve which controls a pressure differential that acts upon the movable wall and is accommodated in a control housing that carries the movable wall, the control valve including at least two concentrically arranged sealing seats and a valve member which defines in the control housing a pneumatic chamber that is acted upon by the pneumatic pressure that prevails in the working chamber wherein the valve member includes two sealing lips of different diameters which define the pneumatic chamber in the control housing, wherein the sealing lips generally align with the sealing seats in an axial direction so that the effective pneumatic surface of the chamber which is influenced by the difference in diameters is generally in conformity with the pneumatic surface defined between the two sealing seats.