摘要:
An anti-skid control system for use in a motor vehicle includes a two-position type control valve for performing increase and decrease in the braking pressure supplied to a wheel braking cylinder for braking a wheel of the motor vehicle. The control valve is operated in accordance with a signal indicative of a duty ratio from an electronic control unit. The electronic control unit estimates a balanced duty ratio whereby the current braking pressure in the wheel braking cylinder is maintained as it is and determines the duty ratio on the basis of the estimated balanced duty ratio in accordance with the locking state of the wheel.
摘要:
In a wheel slip prevention control system for preventing the slippage of the driven wheel occuring when a vehicle is accelerated, a reference speed is derived from the non-driven wheel speed and the driven wheel speed is corrected by a correction value obtained as a function of a driven wheel acceleration value and a non-driven wheel acceleration value. The throttle valve is controlled with speed corresponding to the slipping condition of the driven wheel, i.e., with a control speed derived as a function of the reference speed and the corrected driven wheel speed, so that the slippage is quickly and effectively prevented.
摘要:
Disclosed herein is a vehicle running control device having a slip preventing function where a throttle opening degree of an engine is decreased upon occurrence of slip on drive wheels at starting and acceleration to prevent slip, and a running speed control function where a vehicle running speed is controlled to a target value. The control device comprises a common drive source for the above-mentioned both functions, a reduction mechanism for generating a drive output reduced discretely by driving the drive source in a predetermined direction and in a reverse direction, and link mechanism for effecting an open/close control of a throttle by the drive output. In the running speed control operation, the open/close control of the throttle is effected through the reduction mechanism and the link mechanism by intermittently controlling a driving operation of the drive source in the predetermined direction. On the other hand, upon occurrence of the slip on the drive wheels, the throttle opening degree is decreased to prevent the slip by intermittently controlling a driving operation of the drive source in the reverse direction through the reduction mechanism and the link mechanism. Further, the link mechanism is provided with a damper mechanism for damping a repulsive force to an acceleration operating section due to forcible decrease in the throttle opening degree in the slip preventing operation.
摘要:
In a braking pressure control apparatus for a vehicle, a first valve connected between a hydraulic pressure source and a wheel cylinder serves to permit and inhibit a supply of brake fluid to the wheel cylinder from the hydraulic pressure source. A second valve connected between the wheel cylinder and a reservoir serves to permit and inhibit an escape of the brake fluid from the wheel cylinder toward the reservoir. A control device serves to output control signals to the first and second valves respectively to control the braking pressure in the wheel cylinder in response to a detected running condition of the vehicle. The control device includes a deciding section for deciding whether or not a small variation in the braking pressure in the wheel cylinder should be done on the basis of the detected running condition of the vehicle, and an outputting section for, when the deciding section decides that the small variation in the braking pressure in the wheel cylinder should be done, simultaneously outputting the control signals to the first and second valves to simultaneously execute the supply of the brake fluid to the wheel cylinder and the escape of the brake fluid from the wheel cylinder.
摘要:
An automotive engine throttle control device has a function for effecting traction control for reducing the engine throttle opening upon detection of any slip of driving wheels and a function for effecting an automatic drive control for controlling the vehicle cruising speed in conformity with a command speed. The device has a first lever operatively connected to an accelerator and a second lever operatively connected to the throttle valve. A spring is disposed to resiliently act between the first and second levers. The second lever is actuated by an actuator which operates in response to throttle opening control instructions.
摘要:
A brake control system for a motor vehicle which is equipped with a running state detector for detecting a running state of the motor vehicle so as to adjust a braking pressure in a wheel-braking cylinder of the motor vehicle in accordance with the detected vehicle running state. The brake control system has a first restriction adjusting valve provided between a hydraulic pressure generating source and the wheel-braking cylinder for adjusting the braking pressure to be supplied from the hydraulic pressure generating source to the wheel-braking cylinder, and a second restriction adjusting valve provided between the wheel-braking cylinder and a reservoir for adjusting a braking liquid to be discharged from the wheel-braking cylinder to the reservoir. Also included in the system is a control unit for outputting control signals to the first and second restriction adjusting valves so as to control the braking pressure in the wheel-braking cylinder in accordance with the detected vehicle running state. This arrangement allows setting of the braking hydraulic pressure increasing and decreasing speeds so as to permit a smooth brake control operation.
摘要:
A pressure control valve for use in an automobile braking system includes a spool slidably movable for providing selective fluid communication between a pressure fluid source, a wheel cylinder, and a reservoir. The spool has, or is associated with, a pressure-bearing member responsive to a fluid pressure from the wheel cylinder, for applying a first biasing force to the slidable member to urge the slidable member to a position in which the wheel cylinder and the reservoir communicates with each other. An electromagnetic coil responds to an electric signal for generating an electromagnetic force to urge the slidable member to the above position. The slidable member is normally biased by a spring under a second biasing force, greater than the first biasing force, to urge the slidable member to a position in which the pressure fluid source and the wheel cylinder communicate with each other. The fluid pressure in the wheel cylinder is regulated to cause the sum of the fluid pressure in the wheel cylinder and the electromagnetic force from the electromagnetic coil to counterbalance the second biasing force.
摘要:
An anti-locking control system for use in a motor vehicle having four wheels, comprising a hydraulic pressure supply system for applying a braking pressure from a master cylinder to two pairs of wheel-braking cylinders for braking the pair of wheels and a pump provided in common for the two pairs of cylinders in the hydraulic pressure supply system to decrease both the braking hydraulic pressures in each pair of wheel-braking cylinders. The hydraulic pressure supply system includes a pair of control valves each of which is arranged to have a first position at which the master cylinder is communicated with each of the pair of wheel-braking cylinders and a suction side of the pump is disconnected to the wheel-braking cylinder and a second position for disconnection to the wheel-braking cylinder and communication with the cylinder. Also provided in the control system an electronic control unit for effecting duty control of the pair of control valves so that the time periods at which the pair of control valves are at the second positions are not overlapped with each other. With this arrangement, although the pressure-decreasing is effected by one pump provided in common for the respective wheel-braking cylinders, it is possible to adequately effect the pressure-decreasing with respect to the lower-pressure side wheel-braking cylinder.
摘要:
The present invention is directed to a vehicle motion control apparatus, which includes normally open valves to supply hydraulic pressure discharged from a master cylinder into wheel brake cylinders, normally closed valves to reduce the wheel cylinder pressure, and a proportional pressure difference valve which is disposed between the master cylinder and the normally open valves, to regulate a pressure difference between the hydraulic pressure at the side of the master cylinder and the hydraulic pressure at the side of the normally open valves to be of a desired value. A pressure generating device is provided for generating the hydraulic pressure independently of the master cylinder to supply it into a passage between the pressure difference valve and the normally open valves. The normally open valve connected to one of the wheel brake cylinders in one hydraulic circuit, is placed in its closed position, and the normally open valve connected to the other one of the wheel brake cylinders, is placed in its open position, and then the pressure difference valve is controlled on the basis of the monitored vehicle state variable.
摘要:
A solenoid valve driving device includes a bypassing current path of which one end is connected to a point between a first switching device and a first solenoid valve and another end is connected to a point between a second switching device and a second solenoid valve, and an element disposed in the bypassing current path and having a characteristic that causes current to flow from the first switching device side to a second switching device side. By adopting the above described constitution, through current generated when the first switching device is switched from an OFF-state to an ON-state during duty control of the first switching device can be suppressed by the inductance of the second solenoid valve. In this way, one solenoid valve among a pair of the first and second solenoid valves, which is not operated, has a function of suppressing the through current.