JP2726129B

A brake system having a master brake cylinder embodied as an electrohydraulic booster, this cylinder communicates via a piston rod with a brake pedal. The piston rod acts upon at least one master cylinder piston, via which in turn a brake chamber can be put at brake pressure. As a result, brake fluid flows via brake lines to corresponding wheel brake cylinders. Also associated with the master cylinder piston is a servo piston chamber, which communicates via a control element with an apparatus for supplying power brake fluid. This control element is controlled via a controller. The controller controls the control deviation, which is derived from a set-point value forced by a piston rod travel transducer having a following control unit, and from the actual value, which originates in a travel transducer of the master cylinder piston. As a function of the rod travel the control unit following the piston rod travel transducer generates set-point value indications, which are intended to move the master cylinder piston in accordance with the driver's braking behavior. From the travel transducer signal of the piston rod transducer, via a performance graph, the feedback of the brake pressure to the piston rod is also derived and converted, so that the driver on the one hand can feed in pressure slowly and purposefully without feedback, until automatically, with increasing pressure, or in other words with a corresponding rod travel, the feedback of the brake pressure to the driver's foot begins, and on the other hand, rapid braking is effected with immediate feedback to the driver's foot.