Abstract: In a method of improving the control behavior of an anti-lock control system, criteria for identifying a cornering situation and the direction of curve are obtained from the rotating behavior of the vehicle wheels. For cornering identification, the wheel slip values (&lgr;i) are filtered by way of a first order, low pass and the filtered values are compared. The time constant (T) of the low pass filter is varied as a function of the acceleration (ai) of the respective wheel (i). The time constant (Ti) of the filter starting from a minimum value (Tmin), is increased according to the relation Ti=Tmin+(agrenz−ai)/k1 as soon as the acceleration (ai) of the respective wheel (i) drops below a predetermined limit value (agrenz).

Abstract: In a method for carrying out an automatic braking operation for motor vehicle with an anti-lock system, the pedal position and the brake pressure for the wheels not subjected to ABS control are correlated during the automatic braking operation such that the brake pressure is no greater than would correspond to the position of the brake-actuating device in the case of a normal braking operation. Rapid braking of these wheels is achieved while the pedal position continues to represent a reliable measure of the brake pressure.

Abstract: A braking control system for agricultural tractors wherein individual front and rear wheel hydraulic brakes are operated by a hydraulic braking control unit which is controlled by an electronic control unit to cause it to vary the braking pressure to the individual brakes relative to a reference value set by operation of a brake operating pedal by the tractor operator. The braking control unit varies the braking pressure at the individual wheel brakes in dependence on the associated wheel speed and the tractor ground speed.

Abstract: A braking control system for agricultural tractors comprises:of the type having a pair of front wheels and a pair of rear wheels with at least one pair being driven through a differential and wherein individual wheel brakes are individually controlled through a hydraulic braking control unit which in turn is controlled by an electronic control unit which causes the braking control unit to apply braking pressure to slow the wheels on the inside of the steering bend in response to signals received by a steering angle sensor.

Abstract: An antiskid brake controller, which can secure safety by avoiding a cascade caused when a braking pressure is reduced in a four-wheel-drive vehicle, includes wheel speed sensors braking force adjuster for adjusting a braking pressure and an ECU for calculating the control amount of a breaking force adjuster so as to prevent the locking tendency of each of the wheels based on a wheel speed Vw. The ECU includes means for the wheel deceleration calculator Gw corresponding to the locking tendency of each of the wheels, a basic vehicle calculator speed, a slip amount calculator SL based on the wheel speed Vw and the basic vehicle speed, cascade determination device for determining the occurrence of the cascade state when an unstable state occurs such that the slip amounts of three wheels are larger than a predetermined value and control amount corrector for changing the control amount of the braking pressure in an increasing pressure reduction amount when the occurrence of the cascade is determined.

Abstract: The present invention is directed to a brake control system, which includes a first pressure circuit and a second pressure circuit for communicating a master cylinder with two sets of wheel cylinders, respectively. In each pressure circuit, a modulator is arranged to modulate the braking pressure in each wheel cylinder, a pressure pump is disposed to supply pressurized brake fluid to each wheel cylinder through each modulator, a normally open first valve is arranged to open or close a first passage for communicating the master cylinder with the modulator, and a normally closed second valve is arranged to open or close a second passage for communicating a reservoir directly with the inlet of each pump, or communicating the reservoir with it through the master cylinder. The pressurized brake fluid is supplied to each pressure circuit including the second valve at the inlet of the pump to perform an auxiliary pressurization.

Abstract: To improve the control behavior of an anti-lock control system or brake slip control system, more particularly, to improve the steerability of a vehicle and its drivability when braking during cornering is performed, criteria for cornering identification and for determining the direction of cornering are derived from the wheel slip of the individual wheels. When cornering is identified, the normal control mode which is intended for straight travel and is configured for an individual control of all wheels or an individual control of the front wheels in conjunction with a select-low control of the rear wheels is changed to a cornering control mode. In the cornering control mode, the average pressure level of the curve-inward front wheel is decreased by a predetermined value and the average pressure level of the curve-outward front wheel is increased by a predetermined value.

Abstract: A hydraulic brake system for a vehicle with an anti-lock arrangement operable by wheel brake pressures are individually variable in front wheel brakes and rear wheel brakes, connected to diagonal brake circuits, of a four-wheeled vehicle, in order to reduce or eliminate a threat of wheel locking. The anti-lock arrangement has at least one return pump per brake circuit. The anti-lock arrangement is equipped with a total of four electrically controllable valves. In each of the brake circuits I, II there is one first valve between the master cylinder and a front wheel brake and one second valve between the master cylinder and the rear wheel brake. All the valves are embodied as normally open valves and are electrically closable. Inlets of each of the return pumps communicate directly with the respective front wheel brakes and indirectly with the rear wheel brakes through throttles. Check valves that open toward the inlets of the return pumps are provided in series with the throttles.

Abstract: A control method for a manual back-up electro-hydraulic braking system in which the rear service brakes of the vehicle are intentionally operated in a manual back-up mode under specified non-failure operating conditions to conserve electrical energy. The manual back-up mode for the rear service brakes is initiated if braking is commenced while the vehicle speed is below a near-zero threshold speed. If braking is commenced above the threshold speed, the manual back-up mode for the rear service brakes is initiated when the vehicle speed falls below the threshold and the pressure command for the rear brakes has been substantially constant for at least a predetermined time. In this case, the rear manual back-up mode is initiated by reducing the rear brake pressure command to the rear boost units at a controlled rate until the rear brake pressure reaches the manually developed pressure, and then entering the manual back-up mode.

Abstract: A circuit arrangement for a brake system with electronic brake force distribution control includes circuits which determine the deceleration of the rear wheels and the deceleration of a vehicle or a corresponding reference quantity. The discrepancy of the filtered rear-wheel deceleration from the vehicle deceleration is evaluated for brake force distribution control. To this end, an output signal is produced by way of a differentiator and integrator comparing the rear-wheel deceleration and the vehicle deceleration, and the output signal is evaluated for the control of the braking pressure in the rear-wheel brakes.

Abstract: Before a wheel to be controlled satisfies conditions to shift to ABS control, when a specified or larger deceleration is caused by applying a brake, a wheel for which the difference in rotational speed from that of a wheel having the maximum rotational speed as the reference is equal to or larger than a predetermined value is subjected to the brake pressure increase restraint. At this time, the magnitude of the estimated lateral acceleration value is determined, and when the vehicle is in a sharp turn, pressure increase rates of the inside wheels are set to be particularly small values.

Abstract: In an antilock brake control for a vehicle for individually regulating braking forces of left and right wheel brakes in accordance with a locking tendency of left and right wheels during braking of the vehicle, a steering angle, a vehicle speed and a yaw rate of the vehicle are detected. A reference yaw rate is determined based on the steering angle and the vehicle speed. When a locking tendency of only an outer wheel during turning of the vehicle, of the left and right wheels is detected during turning of the vehicle, the braking force for the outer wheel is regulated in accordance with the tendency of the outer wheel, and the braking force for an inner wheel during turning of the vehicle is regulated in accordance with a difference between the reference yaw rate and the detected actual yaw rate. Thus, it is possible to enhance the turning characteristic while avoiding a loss in total braking force during turning of the vehicle.

Abstract: Apparatus for improving the driving behavior of a vehicle is provided. The vehicle has front and rear axles, each having a plurality of wheels. Each wheel-has a brake. Sensor are provided for measuring the rotational speed of each wheel, the vehicle yaw rate and the vehicle lateral acceleration. An anti-lock braking system provides first preset pressure values for controlling each brake, to prevent the wheels from locking during braking. A traction slip control system provides second preset pressure values for controlling each brake, to prevent the wheels from slipping during acceleration. A brake effort proportioning system provides third preset pressure values for distributing braking pressure between the wheels of the front axle and the wheels of the rear axle. A yawing moment controller provides fourth preset pressure values used to control each brake during cornering, to avoid application to the vehicle of an unbalanced moment which would cause the vehicle to understeer or oversteer.

Abstract: A process and an apparatus are provided for controlling the brake system of a vehicle. A desired value representing the vehicle deceleration is formed depending on a depression signal derived from actuation of the brake pedal by the drive, and additionally depending on the rate of change that signal. The actual vehicle deceleration is compared to the desired value and the vehicle is automatically braked when the actual deceleration deviates from the desired value.

Abstract: Apparatus for improving the driving behavior of a vehicle is provided. The vehicle has front and rear axles, each having a plurality of wheels. Each wheel has a brake. Sensor are provided for measuring the rotational speed of each wheel, the vehicle yaw rate and the vehicle lateral acceleration. An anti-lock braking system provides first preset pressure values for controlling each brake, to prevent the wheels from locking during braking. A traction slip control system provides second preset pressure values for controlling each brake, to prevent the wheels from slipping during acceleration. A brake effort proportioning system provides third preset pressure values for distributing braking pressure between the wheels of the front axle and the wheels of the rear axle. A yawing moment controller provides fourth preset pressure values used to control each brake during cornering, to avoid application to the vehicle of an unbalanced moment which would cause the vehicle to understeer or oversteer.

Abstract: Apparatus for controlling an automotive vehicle is provided. The vehicle has a plurality of wheels, each wheel having an individually operable brake. The apparatus comprises a mechanism for determining the steering angle of the vehicle. A yawing moment controller receives the steering angle and determines a moment that is applied to the vehicle to prevent an undesirable yaw angle, yaw rate or yaw acceleration. Distribution logic receives the output of the yawing moment controller. The distribution logic determines a respectively different weighted coefficient for each individual brake, and an individual braking pressure to be applied to each respective one of the brakes based on the moment and the respective weighted coefficient of the one brake.

Abstract: In a road vehicle electrohydraulic brake system, each wheel brake is assigned a brake-pressure regulating element which can be controlled by an electric motor. At least one electronic retardation desired-value signal transmitter is actuated by the driver. An electronic control unit produces the required actuating signals for the brake-pressure regulating elements from a comparison of the desired-value input signals with actual-value signals characteristic of the vehicle retardation. The brake-pressure regulating elements each comprises a piston pump. The filling and delivery strokes of these elements are performed in a fixed phase relationship with a pump driving element. The output of the pump per pump cycle is regulated opposite the pressure and, in all cases, is small relative to the output, Q.sub.max, required for coupling the maximum value of the brake pressure P.sub.Bmax into the connected wheel brake.

Abstract: Apparatus for improving the driving behavior of a vehicle is provided. The vehicle has front and rear axles, each having a plurality of wheels. Each wheel has a brake. Sensor are provided for measuring the rotational speed of each wheel, the vehicle yaw rate and the vehicle lateral acceleration. An anti-lock braking system provides first preset pressure values for controlling each brake, to prevent the wheels from locking during braking. A traction slip control system provides second preset pressure values for controlling each brake, to prevent the wheels from slipping during acceleration. A brake effort proportioning system provides third preset pressure values for distributing braking pressure between the wheels of the front axle and the wheels of the rear axle. A yawing moment controller provides fourth preset pressure values used to control each brake during cornering, to avoid application to the vehicle of an unbalanced moment which would cause the vehicle to understeer or oversteer.

Abstract: An anti-skid fluid pressure control apparatus including a pair of hydraulic units, each of the hydraulic units consists of a first pair of pressurized fluid supply conduits; a second pair of pressurized fluid supply conduits; a first pair of brake-relieving conduits; a second pair of brake-relieving conduits; fluid pressure pump; hydraulic reservoir; first electro/magnetic inlet valves arranged in the first pair of pressurized fluid supply conduits, respectively; second electro-magnetic inlet valves arranged in said second pair of pressurized fluid supply conduits, respectively; first electro-magnetic outlet valves arranged in the first pair of brake-relieving conduits, respectively; and second electro-magnetic outlet valves arranged in the second pair of brake-relieving conduits, respectively; first connecting conduits for connecting one ends of the first and second pairs of pressurized fluid supply conduits in one of the hydraulic units, to a first brake fluid pressure generating chamber of a tandem master

Abstract: A brake control device includes a master cylinder for generating a brake fluid pressure that is supplied to a first wheel brake via a switching valve and a first normally opened solenoid valve. The brake fluid pressure is also supplied to a second wheel brake via the switching valve and a second normally opened solenoid valve. The first wheel brake and the second wheel brake are associated with a one-way fluid pressure pump. Each of the switching valve, the solenoid valves and the pump is independently controllable. By selecting the condition of each of the switching valve, the solenoid valves and the pump, the brake fluid pressure supplied to each of the wheel brakes is adjustable depending on function which the brake control device is to fulfill.

Abstract: A vehicle (31) has a composite braking system (electric and mechanical). This composite braking system having asynchronous electric motors (4a to 4d) associated with the wheels (2a to 2d) and a mechanical braking device having a hydraulic circuit (14) and mechanical brakes (18a to 18d). The composite braking system also has an electronic measuring device (36) connected to rotation frequency sensors (34a to 34d) disposed on each of the wheels, this electronic device supplying a reference signal to the control circuit (6) of the asynchronous electric motors which regulate the stator frequency of these motors as a function of the value of the reference signal. The braking system of the invention is anti-locking and very effective in any driving situation.

Abstract: The invention is directed to a hydraulic braking system having a master cylinder (10) in which a first piston and a second piston are slidably disposed to define a first pressure chamber (11) and a second pressure chamber (12). A valve device (24) is provided between the first pressure chamber and a reservoir (20). A first pressure control device (30, 31) is provided between the first pressure chamber and wheel cylinders (38, 39), and a second pressure control device (32, 33) is provided between the second pressure chamber and wheel cylinders (40, 41). A pump (27) is provided in a passage connecting the reservoir and the first pressure control device, and driven to supply a brake pressure from the former to the latter.