摘要:
The present invention is directed to a vehicle braking system having a stroke simulator and a servo device, which includes a pressure generator for generating a hydraulic braking pressure, a wheel brake cylinder operatively mounted on each wheel of the vehicle, a pressure control valve device which is disposed in a passage for communicating the pressure generator with the wheel brake cylinder, to control the hydraulic braking pressure supplied to the wheel brake cylinder, and an electronic controller for controlling at least in response to an amount of operation of the brake pedal. A master cylinder is provided for communicating with the wheel brake cylinder and supplying the hydraulic braking pressure into it in response to operation of the brake pedal, when at least one of the pressure generator, the pressure control valve device and the electronic controller is abnormal. A stroke simulator is connected to the master cylinder, and arranged to allow the brake pedal to advance in response to the amount of operation of the brake pedal. And, a servo device is provided for assisting the master cylinder to operate when at least one of the pressure generator, the pressure control valve device and the electronic controller is abnormal.
摘要:
An object of the invention is to increase driving force of driving wheels at starting a vehicle, when the vehicle runs on a μ-sprit road. At first, a road surface for a driving wheel is detected, which has a higher coefficient of friction than that of a road surface for the other driving wheel. An operation for controlling grounded load of the driving wheels is carried out during a period, in which differential rotations of the driving wheels are limited. The grounded load of the driving wheel which is traveling on a high-μ road is increased, whereas the grounded load of the other driving wheel which is traveling on a low-μ road is decreased.
摘要:
A vehicle parking brake system having an AUTO selector for selectively establishing an automatic mode and a manual mode, parking brake units, and an electronic control unit operable in the automatic mode to automatically activate the parking brake units to apply a parking brake to vehicle rear left and right wheels (RW1, RW2) when the vehicle is in a parked state, and to automatically de-activate the parking brake units to remove the parking brake from the vehicle wheel, and in the manual mode to selectively apply and remove the parking brake to and from the vehicle wheels according to operations of a MANUAL MODE control switch. Where the MANUAL MODE control switch is operated in the automatic mode, data indicative of the operation of the control switch is kept stored in a memory until the memory is cleared when predetermined operating state of the vehicle is detected, so that the control of the parking brake units in the automatic mode is restricted to control the parking rake units according to the operations of the MANUAL MODE control switch in the manual mode.
摘要:
In a hydraulic active suspension system, a plurality of actuators having working fluid chambers are provided corresponding to vehicle wheels. Each actuator is adapted to increase and decrease vehicle height in response to the pressure within its working chamber, which is controlled by a pressure control device. Vehicle speed and lateral acceleration are detected by corresponding sensors. A control device is further provided for controlling the pressure control device by compensating values determined base upon the lateral acceleration detected. The control device is adapted to reduce the compensating values in magnitude when the vehicle speed is lower than a predetermined value under which the lateral acceleration sensor sometimes detects a false lateral acceleration, thereby reducing the possibility that the vehicle body may generate an unpleasant roll due to the erroneous control on the pressures within the working fluid chambers based upon a false lateral acceleration.
摘要:
In a fluid pressure type active suspension in a vehicle such as an automobile in which a fluid pressure type actuator supporting a vehicle body from a wheel so as to be able to vary a vehicle height of the vehicle body relative to the wheel in accordance with a fluid pressure supplied in its fluid chamber is operated by a pressure control means which controls the fluid pressure supplied in the fluid chamber of the actuator according to certain control parameters including at least a rate of change of the vehicle height or an acceleration of the vehicle body, the control means is adapted to modify an actual value of the rate of change of the vehicle height or the acceleration of the vehicle body for use in the control of the fluid pressure to be less than the actual value thereof when the rate of change of the vehicle height or the acceleration of the vehicle body is greater than a threshold value therefor.
摘要:
A suspension pressure control system applies a pressure which is proportional to a current level supplied to a solenoid of a pressure control valve to a shock absorber associated with a suspension from the valve. When a pressure in a high pressure line which feeds a high pressure to the pressure control valve falls (rises), the pressure applied to the suspension is decreased (increased). Accordingly, the pressure in the high pressure line is detected by a sensor, and if it is low (high), the current level of the pressure control valve is corrected to a high value (low value). In order to prevent an abnormal pressure rise in the suspension which may be caused by an excessive pressure rise in the high pressure line during an idling operation of an engine, a correction which responds to the pressure of the high pressure line is chosen large when a vehicle speed is equal to zero or very low. In order to prevent an abnormality from occurring in the correction of the pressure which is attributable to an errorneous detected value during a failure of operation of sensor, such detected value is determined to be faulty, and in the event a fault occurred, the correction is modified to a given volume (0) which is allocated to a standard pressure in the high pressure line.
摘要:
A vehicle brake control device includes a brake member, a wheel brake cylinder mounted on a wheel, and a master cylinder. The master cylinder generates a master cylinder hydraulic pressure in response to an operating force applied to the brake member. The brake control device also includes an automatic pressure increasing control device, a braking force control device, a coefficient of friction detecting device that detects a coefficient of friction of the road, and an automatic pressure increasing restraining device. The automatic pressure increasing control device controls automatic pressure increasing operation of the master cylinder based on the operating force applied to the brake member. The braking force control device controls the increased master cylinder hydraulic pressure supplied to the wheel brake cylinder. The automatic pressure increasing restraining device restrains automatic pressure increasing operation of the master cylinder when anti-skid control is being performed with a low coefficient of friction.
摘要:
The invention is directed to a pressure accumulating control system for use in a pressure supply apparatus which has a fluid pump, an electric motor for driving the fluid pump to supply a hydraulic pressure, and an accumulator for accumulating the hydraulic pressure supplied from the fluid pump. The system includes a pressure detection device for detecting the hydraulic pressure accumulated in the accumulator, and a continuous control device for feeding a current to the motor continuously. The continuous control device is adapted to feed the current to the motor continuously, when the pressure detected by the pressure detection device becomes less than a predetermined lower limit, and is adapted to terminate the continuous feeding of the current to the motor, when the pressure detected by the pressure detection device exceeds a predetermined upper limit. The system further includes an intermittent control device for feeding a current to the motor intermittently by a predetermined cycle of time. The intermittent control device is adapted to terminate the continuous feeding of the current to the motor, and is adapted to feed the current to the motor intermittently, when the current is continuously fed to the motor by the continuous control device for a period longer than a predetermined time.
摘要:
In a hydraulic active suspension system, a plurality of actuators having working fluid chambers are provided corresponding to the vehicle wheels. Each actuator is adapted to increase and decrease vehicle height in response to the pressure within its working chamber, which is controlled by a pressure control device. Vehicle speed and vehicle heights at the locations corresponding to the vehicle wheels are detected by corresponding sensors. A control device is further provided for controlling the pressure control device so that the pressures within the working fluid chambers are driven to substantially the desired pressures, the desired pressures determined by, at least, the sum of the first control parameters corresponding to the differences between the actual vehicle heights detected and the associated desired vehicle heights and the second control parameters corresponding to the changing amounts of the vehicle height differences. The second control parameters are so set that the higher the vehicle speed is, the higher the second quantities are in magnitude, enhancing the controllability and stability of the vehicle under higher vehicle speed conditions and ensuring a greater comfortability level of the vehicle under lower vehicle speed conditions.
摘要:
In a hydraulic active suspension system, a plurality of actuators having working fluid chambers are provided corresponding to vehicle wheels. Each actuator is adapted to increase and decrease vehicle height as the results of the supply and the discharge of working fluid to and from its working fluid chamber, respectively. Supplying and discharging devices supply working fluid to and discharge from the working fluid chamber. Vehicle height sensors detect the vehicle heights at the locations corresponding to the vehicle wheels. A control device is further provided. The control device controls the supplying and discharging devices so that the pressure within the working fluid chamber in each actuator may be a value corresponding to the sum of a basic pressure determined according to the running conditions of the vehicle and a compensating pressure determined based upon the integral value of the difference between a standard vehicle height and an actual vehicle height. When the integral value of the difference is larger in magnitude than a predeterminate value, it is reduced in magnitude by the control device so as to prevent the control with the compensating pressure from overriding the control with the basic pressure.