JPS585819B2 - Anti skid control method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an anti-skid control method for safely braking a vehicle by preventing wheel locking that occurs when an excessive brake force is applied to a wheel.

Conventional and well-known anti-skid control prevents wheels from locking or about to lock an actuator, which has a cut valve disposed between a brake mask cylinder and a wheel cylinder, a pressure reducing means for reducing pressure in the wheel cylinder, and a pressurizing means for pressurizing the wheel cylinder. When the condition is detected, the skid signal issued from the computer depressurizes the wheel cylinder by deactivating the actuator using a solenoid valve, etc., and then when the wheel rotation returns, the skid signal disappears. By pressurizing the wheel cylinder again and repeating this operation, braking was achieved without locking the wheel, and the structure of the signal generator and actuator became complicated due to the repeated depressurization and pressurization operations. It had the disadvantage of being expensive.

In order to overcome this drawback, a so-called F. Focusing on the fact that the distribution of braking force between the rear wheels of the F car is very small compared to the front wheels, and that the vehicle is generally more likely to roll when the rear wheels are locked, anti-skid control is used to reduce the amount of braking force distributed between the rear wheels and the rear wheels. Even if the reduced pressure is maintained during braking and the pressurization operation is omitted, the braking force on the rear wheels will be lost during this anti-skid operation, but out of the total braking force, only the rear wheels will be used. It was found that the smaller the distribution, the less harmful effects such as danger.

Therefore, in order to solve the above-mentioned drawbacks, the present invention aims to solve the above-mentioned problems by providing a vehicle in which the distribution of braking force to the rear wheels is small, so that once the pressure in the rear wheel cylinder is depressurized by the skid signal, a decompression release signal is issued during braking. To provide an anti-skid control method which simplifies the mechanisms of a signal generating part and a wheel cylinder pressure control part, and which is inexpensive, by maintaining a reduced pressure state without being affected by skidding.

An embodiment of the present invention will be described below based on the drawings.

Hydraulic pressure is generated in the master cylinder 11 by the depression of the brake pedal 10, and is sent from one chamber to the wheel cylinder 14 of the front right wheel via the conduit 12 and the actuator 13, and is also sent via the actuator 15 to the wheel cylinder 14 of the front right wheel. It is also fed under pressure to the wheel cylinder 16 of the rear left wheel.

Also, from the other chamber there is a conduit 17 and an actuator 18.
It is fed under pressure to the wheel cylinder 19 of the front left wheel via the actuator 20, and also to the wheel cylinder 21 of the rear right wheel via the actuator 20.

The actuators 13 and 18 on the front wheel side are operated by sensors 22 and 2 that detect the rotational states of the front right wheel and front left wheel, respectively.
When the computer 24 is activated by the output of 3 and the wheels are about to lock, it issues a pressure reduction command signal to reduce the pressure in the wheel cylinder 14.19, and does not reduce the pressure in the wheel cylinder 14.19. The state is detected by the sensors 22 and 23, and the computer 24 cancels the pressure reduction command signal to restore the pressure in the wheel cylinders again, and thereafter repeats this operation to brake the front wheels.

Moreover, the actuator on the rear wheel side is the brake pedal 10.
A brake switch 28, which is activated when the brake pedal is pressed, and a sensor 25, which detects the rotational state of the right rear wheel and the left rear wheel, respectively.
The command circuit 27 is activated by the output of 26, and when the rear wheels are about to lock, a pressure reduction command signal is issued to reduce the pressure in the wheel cylinders 16.21, and the hydraulic pressure in the wheel cylinders 16.21 is returned to the reservoirs 29 and 30, so that no pressure reduction occurs. The pressure reducing operation of the rear wheel cylinder is maintained until the pressure on the brake pedal 10 is released.

Next, the specific configuration of the command circuit 27 is shown in FIG.
As other inputs, the output of the plex switch 28 acts, and the output of the AND circuit 30 becomes an output signal that commands the operation of the actuator 16.21, and this signal acts as a feedback to the input of the OR circuit 29, When the sensors 25 and 26 detect a state in which the wheels are likely to lock, they send an ON signal to the OR circuit 29 and send an ON signal, which is the output of the OR circuit 29, to the AND circuit 30.
Also, when the brake pedal 10 is depressed, the brake switch 2
8 also has no effect on the AND circuit 30, and the output of the AND circuit 30 becomes the ON signal, and the actuator 16.2
1 is generated, and the AND circuit 30
The output of the on signal is fed back to the input of the OR circuit 29, so that even if the sensor 25, 26 detects that the wheel rotation has returned and changes to an off signal, the output of the brake switch 28 remains on. As long as the signal is maintained, that is, while the brake pedal 10 is depressed, once the pressure reduction release command signal is generated, the pressure reduction operation of the wheel cylinders 25 and 26 is maintained without restoring the pressure in the wheel cylinders.

The depressurization of the wheel cylinders 25 and 26 can be released only after the pressure on the brake pedal 10 is released.

As explained above, according to the present invention, the anti-skid control for the rear wheel side where the braking force distribution is small is performed by maintaining the pressure reducing operation of the rear wheel cylinder once a pressure reduction command signal for the rear wheel cylinder is generated. By performing anti-skid control without performing pressure recovery operation of the cylinder, the signal generating section of the command circuit 27 only needs to have the function of issuing a pressure reduction command signal, and detects when the rotational state of the wheel has returned as in the conventional case. There is no need for a release signal generator to cancel the pressure reduction command signal, and the actuator only performs the pressure reduction operation to return the wheel cylinder pressure to the reservoir, making recovery easier compared to the conventional type that repeatedly reduces and pressurizes. For pressure operation, it is not necessary to provide a special pressurizing means other than the master cylinder, such as a pump means, and the disadvantages of unstable braking due to air intrusion and power loss due to pump drive, which are caused by such pressurizing means, are eliminated. In addition, since it is not necessary to provide a volume increasing means on the wheel cylinder side for pressure reduction operation, the structure is simple and can be manufactured at low cost, which is excellent in practical terms.

Although a preferred embodiment of the present invention has been disclosed, it is obvious that similar effects can be obtained even if this is applied to a type of braking system that does not include anti-skid control means on the front wheel side, for example. .

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing one embodiment of the present invention, and FIG. 2 is a circuit diagram showing one embodiment of a command circuit in the present invention. 10... Brake pedal, 11... Master cylinder, 1
6,21...Rear side wheel cylinder, 15.20...
Sensor, 27...command circuit, 28...brake switch.

Claims (1)

[Claims] 1 When the brake pedal is operated, brake pressure is generated in the mask cylinder, the brake pressure is not applied to the wheel cylinder, and the wheels are not braked, and the wheel on the side with less braking force distribution is about to lock, this condition is detected. and commanding an actuator disposed between the mask cylinder and its wheel cylinder to perform a pressure reduction operation using a command means, and returning the wheel cylinder pressure to a reservoir so that the pressure reduction operation is maintained without pressure reduction while the brake pedal is operated. An anti-skid control method characterized by: