Robert Boschgmbh

Lucas Industries Public Limited Company

Dieter Roller

Heinz Leiber

Wolf-Dieter Jonner

Volker Braschel

Eberhard Schnaibel

Alfred Sigl

Franz Brugger

Hubert E Schmitt

Gerd Reimann

Wolfgang Korasiak

Herbert Demel

Method of generating a signal to indicate a curve

Anti-lock braking system

A method of controlling the brake pressure in an antilock (ABS) vehicle brake system provides for adapting the wheel at which the brake is applied to the optimum course of the coefficient of friction/slip curve by determining the rotational retardation of the braked wheel, upon initiation of a braking action, after given time intervals each and comparing it with the rotational retardation of the preceding time interval. Moreover, the brake pressure is varied in response to the result of the comparison. The renewed acceleration of the retarded wheel also is monitored accordingly so as to effect further lowering of the brake pressure if the renewed acceleration or the gain in acceleration is too small.

Method of controlling the brake pressure in an anti-lock vehicle brake

To counteract the tendency of over-steering when a vehicle operates in a curved path, and one of the wheels--typically the wheel at the inner side of the curve exhibits a tendency to block and, then, braking pressure is reduced to one of the front wheels only, the braking pressure applied to the rear wheel or wheels is reduced. If braking pessure is reduced to both of the front wheels, braking pressure being applied to the rear wheels is controlled, independently, in accordance with anti-brake lock control considerations, which have priority over dropping of braking pressure to prevent over-steering.

Method of controlling braking of a vehicle operating in a curved path,

An automotive engine forming part of a motor vehicle is controlled to avoid slipping or spinning of a driven wheel by controlling the maximum rate of change of fuel which can be supplied to the engine, for example, by limiting the speed of deflection of a throttle flap (6) driven by a servo motor (7). The deflection speed, limited for example by a voltage divider (14) can be controlled as a function of operating parameters of the engine or the vehicle, for example, vehicle speed (V.sub.F), engine speed (n.sub.M), engine loading or a percentage of engine loading, actual wheel slip, actual angle or deflection position of the throttle flap, and the like. Further, non-linearities between deflection of an operator actuated pedal, such as a gas pedal (1) and actual deflection of the control flap (6) can be compensated for, for example, in a difference forming circuit (9) providing an output error signal for the servo motor (7) or by software, e.g. by recourse to non-linear characteristics stored in a table or graph. The duration of limiting can be determined by timing circuit connected to a terminal (p) for example, on the voltage divider (14). The system can be instrumented electrically (FIG. 2) or, for example, hydraulic-electrically (FIG. 3).

System for controlling the fuel supplied to an automotive engine

To permit operation of an anti-skid or anti brake-lock system with wheels having dual braking cylinders, controlled by separate braking valves, control signals to control separate brake valves (V.sub.11, V.sub.12) at respective sides of the vehicle are derived for a first braking system (I) in accordance with well known technology, based on wheel acceleration, deceleration and the like, processed in an anti-skid control unit (9), and a second braking system, controlled by a single valve (V.sub.2), is provided connected to the second braking cylinders in both wheels. The control signals for the second valve (V.sub.2) are generated as a function of the signals arising in the first system (I) by a logic circuit (15-25) including timing elements (15, 16, 19, 21) responsive to leading and trailing flanks, respectively, of opening and closing signals arising in the first braking system (I) under command of the wheel anti-lock or anti-skid control unit (9), to drop braking pressure in the second system (II) if unstable operation of the wheels, based on braking in the first system (I) occurs, and raising braking pressure only after a time delay (19; T.sub.2) if an increase in braking pressure in the first system occurred. As an override safety, response of the braking control unit (9) is indicated by a separate override signal, absence of which leaves the second braking system (II) unaffected, but presence thereof prevents raising of braking pressure in the second system during response of the anti-skid unit and controlling the first system.

Vehicular anti-skid braking system

Growing community of inventors

Neuwied, Germany

Dieter Roller