摘要:
An anti-skid control system for an automotive vehicle is provided with braking condition detectors for detecting at least a running condition of the vehicle in braking operation and producing a detected signal corresponding to the running condition. The detected signal is compared with a reference value to produce a braking condition signal. In response to the braking condition signal, selectively provided is one control mode of a simultaneous control mode for controlling simultaneously a braking force applied to both of a pair of right and left road wheels and an independent control mode for controlling independently a braking force applied to each of the right and left road wheels. Then, the braking force applied to the right and left road wheels is controlled in accordance with the control mode.
摘要:
An antiskid device according to this invention controls the hydraulic pressure to vehicle brakes based on the rotational speed of the wheel having the smallest coefficient of friction until a standard vehicle velocity becomes less than a predetermined velocity. Further, the antiskid device controls the hydraulic pressure to the brakes based on the speed of each wheel if the standard vehicle velocity becomes less than the predetermined velocity. Accordingly, directional stabilization of the vehicle is maintained when the vehicle runs at high speed, and at low speed, the braking range for stopping the vehicle is mainimized by utilizing the braking force more efficiently.
摘要:
Brake control apparatus, having an antiskid control for decreasing skidding of wheels are provided by segmenting a brake control mode into three domains or more including "reducing", "hold" and "intensifying". A minimal memory capacity is provided to store constants for specifying functions indicating boundaries of the control mode domains, and the constants are particularly given to coordinate with a cars deceleration. Thus, uniformity may be obtained between resulting operations and decisions.
摘要:
An antiskid control system is disclosed in which a single solenoid-operated switching valve connects a single wheel brake selectively to a high pressure or low pressure from a source of brake pressure. After the decompression of a wheel brake pressure, a repetitive intensifying operation is executed with a period of 40 msec in which an intensifying and a decompressing operation take place alternately. During the repetitive intensifying operation, the duty cycle for the intensifying operation is increased at a given rate. A flash intensification is executed immediately before the repetitive intensification. An initial value of the duty cycle for the repetitive intensification which occurs after the decompression of a second and a subsequent pass is chosen in proportion to the time duration of the previous repetitive intensifying operation and in inverse proportion to the immediately preceding decompressing interval.
摘要:
A braking force distribution control device for an automotive vehicle is designed to make it possible to initiate a braking force distribution control as rapidly as possible upon rapid braking operation while at the same time being capable of preventing a malfunction of the braking force distribution control even when one of hydraulic pressure lines fails. The braking force distribution control establishes a predetermined relationship between the wheel cylinder pressure of a front wheel and a wheel cylinder pressure of a rear wheel on the basis of a comparison between the wheel speeds of the front and rear wheels. The braking force distribution control is initiated when the decelerations of all the wheels exceed a set value.
摘要:
A fluid pressure source apparatus includes a pump, an accumulator for receiving pressure from the pump, a pressure switch for detecting the pressure in the accumulator, an electric motor for driving the pump, and a motor control device for driving the motor when the pressure switch detects a low pressure. A current detecting device detects a motor current value of the motor and a control unit determines whether the accumulator or the motor is experiencing an abnormality based on the motor current value. The control unit determines whether the motor current value occurring during a first set time following the start of driving of the motor is greater than a first set value. If the motor current value is not greater than the first set value, the control unit determines that the current detecting device is experiencing an abnormality. If there is no such abnormality information, the control unit compares the motor current value with predetermined values. If the motor current value continues to be less than a lower limit value for at least a predetermined length of time, the control unit determines that there is a low pressure abnormality. If the motor current value continues to be greater than an upper limit value for at least a predetermined length of time, the control unit determines that there is a motor lock abnormality.
摘要:
The invention is directed to an arrangement for controlling a braking force applied to each of front and rear road wheels of a vehicle depending upon a braking condition, with a hydraulic braking pressure supplied to each of the wheel brake cylinders through an actuator. The actuator is controlled by a braking force controller into which output signals of wheel speed sensors are fed. On the basis of the wheel speeds detected by the sensors, an estimated vehicle speed is calculated, and then a varying rate of the estimated vehicle speed is calculated. Furthermore, a wheel speed differential between the front and rear road wheels (or, a wheel slip rate differential therebetween) is calculated. Only when the wheel speed differential (or, the wheel slip rate differential) exceeds a predetermined value, the varying rate of the estimated vehicle speed is compared with a standard rate to estimate a coefficient of friction of the road surface. Then, the hydraulic braking pressure applied to each of the wheel brake cylinders is controlled by the braking force controller in accordance with the estimated coefficient of friction and in response to the each wheel speed.
摘要:
An anti-skid brake system for a wheeled vehicle including speed sensors for detecting each speed of road wheels of the vehicle and for producing an electric signal indicative of the detected speed of the road wheels, an electronic control apparatus arranged to be applied with the electric signal from the speed sensors for producing a control signal in accordance with conditions of a travel road of the vehicle in braking operation, and an electrically operated actuator arranged to be activated under control of the control apparatus for controlling a hydraulic braking pressure applied to each brake cylinder of the road wheels in response to the control signal, wherein an acceleration speed of the road wheels is calculated in response to the electric signal from the speed sensors, a stepped portion on the travel road is detected by determination of the fact that the detected speed of the road wheels becomes higher than a predetermined reference speed within a predetermined time immediately after activation of the actuator and that the calculated acceleration speed of the road wheels becomes smaller than a predetermined negative value and larger than a predetermined positive value within the predetermined time, and the actuator is deactivated upon detection of the stepped portion on the travel road.
摘要:
When a vehicle stops, a brake control unit maintains a braking force applied on a wheel by a braking-force application unit for maintaining a halted state. In this state, if a driver depresses the accelerator pedal to execute starting of the vehicle, the braking force is gradually decreased, and the vehicle starts at a speed that accords with a degree of accelerator opening and a gradient of a road on which the vehicle is stopped. When a movement direction at this time is the same as a movement direction intended by the driver, the braking force is decreased to zero for smooth starting. When the movement direction is opposite to the intended movement direction, the braking force is increased to control the movement in the opposite direction, such that the movement changes from the opposite direction to the same direction, and finally, smooth starting in the desired direction is executed.
摘要:
When a vehicle stops, a brake control unit maintains a braking force applied on a wheel by a braking-force application unit for maintaining a halted state. In this state, if a driver depresses the accelerator pedal to execute starting of the vehicle, the braking force is gradually decreased, and the vehicle starts at a speed that accords with a degree of accelerator opening and a gradient of a road on which the vehicle is stopped. When a movement direction at this time is the same as a movement direction intended by the driver, the braking force is decreased to zero for smooth starting. When the movement direction is opposite to the intended movement direction, the braking force is increased to control the movement in the opposite direction, such that the movement changes from the opposite direction to the same direction, and finally, smooth starting in the desired direction is executed.