Continental Teves, Ag and Company Ohg

Itt Manufacturing Enterprises, Inc.

Jose Gonzales

Peter Drott

Michael Vogt

Horst Kr&auml;mer

Manfred Rüffer

Jürgen Schonlau

Hans-J&ouml;rg Feigel

Thorsten Neu

Uwe Kley

The brake actuation device of a motor vehicle brake system includes a pneumatic brake booster, the interior of which is subdivided into at least one vacuum chamber and one working chamber, a master brake cylinderand a pneumatic motor-and-pump assemblyfor providing the vacuum in the vacuum chamber, which has a vacuum pumpand a motordriving the vacuum pump. A vacuum level in the vacuum chamber or a difference in pressure between the vacuum chamber and the working chamber is sensed using a sensor, and the motor-and-pump assemblyis enabled by an electronic control unitwhen the vacuum falls below a first defined bottom vacuum level Pe in the vacuum chamber and is disabled when a second defined top vacuum level Pa is reached. The rotational speed np of the motor-and-pump assemblyis controlled depending on driving conditions of the vehicle.

Hydraulic unit

The present invention relates to a brake force booster for automotive vehicles which includes a booster housing whose interior space is subdivided by a movable wall into a working chamber and a vacuum chamber, and a control housing which carries the movable wall and in which a control valve is arranged for controlling a pressure differential that acts upon the movable wall, the said control valve being operable by an operating rod by way of a valve piston and by an electromagnet. According to the present invention, the brake force booster is characterized in that the electromagnet is actuatable in dependence on the relative displacement between the valve piston and the control housing detected by a sensor. This arrangement makes possible a very simple control of a brake assist function because the signal of the sensor can be used both for the activation and the deactivation of the electromagnet. This means that the brake assist function can be triggered and/or terminated only on the basis of the signals of one single sensor.

Brake power booster and a method for controlling the same

A brake power booster for automotive vehicles includes a control valve that is operable by an electromagnet irrespective of an actuating rod displacing a valve piston, the electromagnet actuating a third sealing seat which permits ventilation of the working chamber. The valve member of the control valve has passages which allow a pneumatic pressure compensation. To eliminate a pneumatic force component which counteracts the force generated by the electromagnet, the passages are provided radially outside the area delimited by the electromagnetically operable sealing seat on the sealing surface of the valve member.

Pneumatic brake power booster with control housing having an electromagnetically operable control valve

Growing community of inventors

Bad Oeynhausen, Germany

Jose Gonzales