Abstract: A braking force maintaining apparatus executes hill-hold control in which braking force applied to each of wheels of a vehicle is maintained by a braking device even after release of a brake pedal. An electronic control unit determines whether the yaw rate of the vehicle is greater than or equal to a predetermined threshold value and whether the wheels are held in a locked state by the braking force applied by the braking device. If the wheels are held in the locked state and the yaw rate is greater than or equal to the threshold value, the electronic control unit controls the braking device in such a manner that the braking force acting on two or more of wheels including at least a specific wheel falls below the braking force at the start of the hill-hold control.

Abstract: A brake control apparatus which is used in a vehicle having wheels on left and right sides, and controls a braking force provided to each wheel is disclosed. The brake control apparatus is provided with a vehicle body speed calculating section, a steering angle calculating section, and an ECU. A braking force is provided to a wheel on the inner side with respect to the vehicle turning direction in the case where the absolute value of the steering angle is equal to or greater than the preset threshold value of the steering angle. In the case where the vehicle body speed is less than the preset speed threshold value, the braking force becomes smaller than the braking force in the case where the vehicle body speed is equal to or greater than the speed threshold value.

Abstract: A braking force maintaining apparatus of a vehicle includes a reference braking force setting section, a threshold value setting section, a braking force change rate detecting section, and a change rate determining section. The reference braking force setting section sets, as a reference braking force, a braking force acting on wheels of the vehicle after a reference time has elapsed since stopping of the vehicle. The threshold value setting section sets a threshold value by adding the reference braking force to a predetermined reference value. The braking force change rate detecting section detects a change rate of the braking force acting on the wheels after the threshold value has been set. The change rate determining section determines whether the detected change rate is a negative value.

Abstract: Information related to a throttle opening degree, a real engine speed, etc. is transmitted from, for example, an EFI-ECU to a brake ECU. The brake ECU then derives an engine speed when no load is applied from the throttle opening degree. When the difference between the engine speed when no load is applied and the real engine speed is equal to or above a predetermined value, it is determined that clutch engagement has taken place. As a result of using this configuration, the device is able to detect respective clutch engagement timings of different individuals and release holding of braking force in accordance with these timings, without having to provide the device with components like a clutch sensor, which are only necessary for detecting the timing of clutch engagement.

Abstract: A brake control apparatus which is used in a vehicle having wheels on left and right sides, and controls a braking force provided to each wheel is disclosed. The brake control apparatus is provided with a vehicle body speed calculating section, a steering angle calculating section, and an ECU. A braking force is provided to a wheel on the inner side with respect to the vehicle turning direction in the case where the absolute value of the steering angle is equal to or greater than the preset threshold value of the steering angle. In the case where the vehicle body speed is less than the preset speed threshold value, the braking force becomes smaller than the braking force in the case where the vehicle body speed is equal to or greater than the speed threshold value.

Abstract: A braking force maintaining apparatus executes hill-hold control in which braking force applied to each of wheels of a vehicle is maintained by a braking device even after release of a brake pedal. An electronic control unit determines whether the yaw rate of the vehicle is greater than or equal to a predetermined threshold value and whether the wheels are held in a locked state by the braking force applied by the braking device. If the wheels are held in the locked state and the yaw rate is greater than or equal to the threshold value, the electronic control unit controls the braking device in such a manner that the braking force acting on two or more of wheels including at least a specific wheel falls below the braking force at the start of the hill-hold control.

Abstract: A braking force maintaining apparatus of a vehicle includes a reference braking force setting section, a threshold value setting section, a braking force change rate detecting section, and a change rate determining section. The reference braking force setting section sets, as a reference braking force, a braking force acting on wheels of the vehicle after a reference time has elapsed since stopping of the vehicle. The threshold value setting section sets a threshold value by adding the reference braking force to a predetermined reference value. The braking force change rate detecting section detects a change rate of the braking force acting on the wheels after the threshold value has been set. The change rate determining section determines whether the detected change rate is a negative value.

Abstract: Information related to a throttle opening degree, a real engine speed, etc. is transmitted from, for example, an EFI-ECU to a brake ECU. The brake ECU then derives an engine speed when no load is applied from the throttle opening degree. When the difference between the engine speed when no load is applied and the real engine speed is equal to or above a predetermined value, it is determined that clutch engagement has taken place. As a result of using this configuration, the device is able to detect respective clutch engagement timings of different individuals and release holding of braking force in accordance with these timings, without having to provide the device with components like a clutch sensor, which are only necessary for detecting the timing of clutch engagement.

Abstract: In an antilock brake system in which brake fluid that flows out to a low back-pressure reservoir at the time of a reduction in brake pressure is fed into a wheel brake by a motor driving pump without passing through a control valve to thereby gradually increase the pressure, it is possible to increase the brake fluid pressure to a pressure sufficient to prevent wheel lock even if the road surface has a low coefficient of friction. If, at the time of the reduction in brake fluid pressure, a device for estimating the coefficient of friction of the road surface determines that the road surface coefficient of friction is low, the motor is deactuated (or operated at low velocity) so that the pump will not feed brake fluid to the wheel brake (or so that the amount of brake fluid fed from the pump to the wheel brake is reduced).

Abstract: The present invention is directed to an anti-skid control system which includes a return passage provided for communicating a wheel brake cylinder with an actuator. A pressure pump is disposed in the return passage, and a reservoir is disposed in the return passage at the inlet port's side of the pump. The reservoir stores the brake fluid in the wheel brake cylinder through the actuator to decrease the wheel cylinder pressure. The pump discharges the brake fluid stored in the reservoir into the return passage thereby to gradually increase the wheel cylinder pressure. The amount of brake fluid stored in the reservoir is estimated on the basis of the amount of brake fluid fed into the reservoir and the amount of brake fluid discharged therefrom. The amount of brake fluid fed into the reservoir is estimated on the basis of the wheel cylinder pressure provided when the pressure decreasing operation starts, and in response to the pressure decreasing time.

Abstract: A pressure control apparatus is operated to connect a wheel cylinder to a reservoir via a return fluid passage so that brake fluid will be stored in the reservoir to reduce the pressure. In accordance with the operation of a fluid pressure pump, the brake fluid is discharged from the reservoir into the return fluid passage to supply the brake fluid to the wheel cylinder, so that the wheel cylinder pressure is gradually increased. Based on detection of a sharp decrease of the motor load, it is estimated that the reservoir has become empty. Then, brake fluid is taken from a fluid pressure generating apparatus into the wheel cylinder.

Abstract: The present invention is directed to an anti-skid control system which includes a pressure generator to supply a hydraulic braking pressure into a wheel brake cylinder through an actuator. A return passage is provided for communicating the wheel brake cylinder with the actuator. A pressure pump is disposed in the return passage, and a reservoir is disposed in the return passage at the inlet port's side of the pump. The reservoir stores the brake fluid discharged from the wheel brake cylinder through the actuator to decrease the wheel cylinder pressure. The actuator blocks the communication between the pressure generator and the wheel brake cylinder, and then the pump discharges the brake fluid stored in the reservoir into the return passage thereby to gradually increase the wheel cylinder pressure.

Abstract: The anti-skid control system is capable of performing highly reliable anti-skid control through its accurate estimation of the vehicle speed and proper compensatory control even when sharp braking occurs or in the brake fluid pressure control on road surfaces with a low coefficient of friction likely to cause considerable fluctuations in wheel acceleration. The anti-skid control system is provided with a fluid pressure generating device, a fluid pressure controlling device, a wheel velocity detecting device, a standard speed setting device, a fluid pressure controlling mode setting device which sets either the pressure decrease mode or the pressure hold mode when the wheel velocity declines to a level lower than the standard speed and sets the pressure increase mode when the wheel velocity is equal to or higher than the standard speed.

Abstract: The anti-skid control system is constructed with a brake fluid pressure source for generating brake fluid pressure at high and low levers, a switching valve feeding either high pressure or low pressure to the wheel cylinders, a wheel velocity detecting device sensing the driving wheel rotating speed, an acceleration detecting device detecting the vehicle acceleration and a first arithmetic operation device for finding the estimated vehicle speed and the wheel rotating acceleration based on the wheel velocity detected by the wheel velocity detecting device and the vehicle body acceleration detected by the acceleration detecting device. A brake fluid pressure controlling device is provided for increasing, decreasing or maintaining the brake fluid pressure in the wheel cylinders, controlling the switching valve on the basis of wheel velocity, estimated vehicle speed, and wheel rotating acceleration.

Abstract: An anti-skid control system for an automotive vehicle is provided with an actuator which is disposed in a hydraulic circuit between a pressure generator and a wheel brake cylinder. The actuator is arranged to control the hydraulic braking pressure applied to the wheel brake cylinder. In response to a wheel speed detected by a wheel speed detector, it is determined in an electronic control unit whether a condition for decreasing the braking pressure is effected. When this condition is effected, the decrease mode is provided in the control unit. When a predetermined period of time lapses after the decrease mode is initiated, the decrease mode is turned to a pressure control mode for applying the braking pressure to prevent the road wheel from being locked. When the condition is not effected during the predetermined period of time after the decrease mode is initiated, the decrease mode is turned to a direct supply mode for directly communicating the pressure generator with the wheel brake cylinder.

Abstract: The invention is directed to an arrangement for controlling a braking force applied to a road wheel, with a hydraulic braking pressure supplied to a wheel brake cylinder through an actuator. A standard speed is set on the basis of a wheel speed detected by a wheel speed sensor, and a peak of the wheel speed changing from increase thereof to decrease thereof is detected. A coefficient of friction of road surface is determined on the basis of a vehicle acceleration detected by an acceleration sensor. The actuator is controlled according to a pressure control mode selected from a decrease mode for decreasing the pressure, a hold mode for holding the pressure, a first increase mode for increasing the pressure when the wheel speed exceeds the standard speed, and a second increase mode for increasing the pressure when the wheel speed exceeds the peak of the wheel speed.

Abstract: The anti-skid control system is provided with wheel velocity sensors only for the driving wheels and yet is capable of performing the anti-skid control through its accurate estimation of the vehicle speed and proper compensatory control even when sharp braking occurs immediately upon the release of the accelerator after the occurrence of acceleration slip. The anti-skid control system is capable of starting the anti-skid control with certainty even when the braking operation is not detected because of a failure in the operation of the brake switch. The system is provided with a fluid pressure generating device, a fluid pressure controlling device, a brake operation detecting device, an acceleration detecting device, a wheel velocity detecting device, a braking force controlling device, a brake force correcting device and an acceleration slip detecting device.

Abstract: The invention is directed to an anti-skid control system for controlling a braking force applied to a road wheel with a hydraulic braking pressure supplied to a wheel brake cylinder through a pressure control valve controlled by an electronic controller. On the basis of a wheel speed of the road wheel detected by a wheel speed sensor, the controller calculates an estimated vehicle speed and sets a reference speed on the basis thereof. In the controller, the wheel speed is compared with the reference speed, and in response to a result of comparison the hydraulic pressure supplied to the wheel brake cylinder is controlled by the pressure control valve. Through an adjustment by the controller, the hydraulic braking pressure is decreased in response to a change of difference between the wheel speed and the estimated vehicle speed for a certain period of time.

Abstract: The invention is directed to an arrangement for monitoring a road condition which determines the coefficient of friction of the road surface on the basis of a signal corresponding to an acceleration of a vehicle detected by an acceleration sensor. The signal is converted into one of at least two predetermined values by conversion means in response to a magnitude of the acceleration every cycle of a predetermined time period. The converted value is summed up by summing means by a predetermined number of consecutive cycles to provide a total value in the last cycle thereof which is stored in memory means. Then, in determination means, one of at least two standard values is selected in response to the condition of increase or decrease of the total value in the present cycle provided by the summing means as compared with the total value in the previous cycle stored in the memory means.

Abstract: The anti-skid control system is provided with wheel velocity sensors only for the driving wheels and is capable of performing the anti-skid control through its accurate estimation of the vehicle speed and proper compensatory control even when sharp braking occurs immediately upon the release of the accelerator after the occurrence of acceleration slip. The anti-skid control system is capable of starting the anti-skid control with certainty even when the braking operation is not detected because of a failure in the operation of the brake switch. The system is provided with a fluid pressure generating device, a fluid pressure controlling device, a brake operation detecting device, an acceleration detecting device, a wheel velocity detecting device, a braking force controlling device, a first estimated vehicle speed setting device and a second estimated vehicle speed setting device.