JPH065930Y2 - Anti-skid controller - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to an anti-skid control device for preventing wheel lock by brake hydraulic pressure control.

(Prior Art) During braking of a vehicle, the rotation state of the wheels or the propeller shaft, that is, the deceleration or slip ratio of the wheels is detected, and the brake fluid pressure is adjusted so as to maintain a certain slip ratio according to the detected value. An anti-skid control device for controlling the vehicle to obtain maximum deceleration and lateral stability of the vehicle body is already known.

Here, for example, when the vehicle travels on a road surface having a high friction coefficient μ between the tire and the road surface, that is, a paved road, the anti-skid control device for the high-μ road uses the anti-skid control means for the high-μ road. When anti-skid control is performed and the vehicle travels on a road surface with a low friction coefficient μ, that is, on a snowy road, the low-μ road anti-skid control means reduces the low μ
Anti-skid control for roads is performed, and the judgment of the high μ road and the low μ road is made by the G mounted on the vehicle body.
It is determined based on a signal from a sensor (also referred to as an acceleration / deceleration sensor). Incidentally, when the determination of the high μ road and the low μ road based on the signal from the G sensor is added, this is as follows.
This is because the deceleration of the vehicle that occurs when the braking force increases until the wheels tend to lock and the antiskid control is performed is governed by the friction coefficient between the wheels and the road surface. That is, the deceleration (signal from the G sensor) generated in the vehicle at the time of shifting to the anti-skid control uses a phenomenon that it is low on the low μ road and high on the high μ road. For example, Japanese Patent Publication No. 58-47391. Are known from.

(Problems to be solved by the invention) Here, the vehicle equipped with the anti-skid control device is a low μ road having a relatively high road surface resistance such as a corrugated road, a gravel road, an uneven road, and a ground road, that is, a wheel. When traveling on a road surface with a low friction coefficient that gives a strong impact (hereinafter referred to as a bad road), the road surface resistance is high unlike snow roads as described above, so the wheels tend to lock when braking the vehicle. It is desirable to perform brake fluid pressure control, that is, anti-skid control for high μ roads to shorten the braking distance. However, if the conventional device is installed and the vehicle runs on the rough road, the low μ
Because of the road, the acceleration / deceleration in the traveling direction of the vehicle at the time of braking is small, and the low μ road signal is sent from the G sensor. Therefore, the anti-skid control for the low μ road, that is, the brake fluid pressure is immediately increased. It was even dangerous because the braking distance was greatly extended as a result of the control being carried out.

An object of the present invention is to provide an anti-skid control device having excellent vehicle stability that can reduce a braking distance when traveling on a low μ road having a high comparative road surface resistance such as a corrugated road, a gravel road, an uneven road, and a ground road. is there.

(Means for Solving Problems) In order to achieve the above-mentioned object, the anti-skid control device of the present invention has a detection means for transmitting a detection signal according to the displacement of the vehicle height and a detection signal when the brake is turned on. And a comparing means for comparing the output from the calculating means and a predetermined value, and when the output is equal to or more than the predetermined value, a bad road signal is transmitted as a bad road. A high μ road signal generating means for generating and transmitting a high μ road signal, and when the bad road signal is received, the high μ road signal from the G sensor is used instead of the high μ road signal.
The present invention is characterized by comprising a controller comprising switching means for sending the high μ road signal from the road signal generating means to the anti-skid control means.

(Operation) According to the present invention, the detection signal from the detection means is inputted to the calculation means, and the fluctuation frequency for which the fluctuation frequency of the detection signal when the brake is turned on is calculated by the calculation means is inputted to the comparison means. If the fluctuating frequency is equal to or higher than a predetermined value that can be regarded as a bad road by the comparison means, a bad road signal is input to the switching means. Then, in the switching means, the high μ road signal from the high μ road signal generating means is sent to the anti-skid control means instead of the road surface μ signal from the G sensor.
The brake fluid pressure control for the high μ road is performed by the high μ road anti-skid control means.

Embodiment An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing the configuration of an anti-skid control device showing an embodiment of the present invention. As shown in FIG.
The anti-skid control device of the present invention detects a G-sensor 1 that sends a high μ road signal when the vehicle has a high acceleration / deceleration and a low μ road signal when the vehicle has a low acceleration / deceleration, and detects the wheel speeds up to the vehicle. A wheel speed sensor 30 that sends a speed signal corresponding to the wheel speed, a brake switch 40 that detects the operation of a brake pedal and sends an ON / OFF signal thereof, and a detection signal that sends a detection signal according to the displacement of the vehicle height of the vehicle. A vehicle height sensor 60 as a means, each modulator 50 for controlling the brake fluid pressure of each wheel, the G sensor 1 and a wheel speed sensor.
The controller 5 sends a drive signal to each modulator 50 in response to signals from the brake switch 40 and the vehicle height sensor 60. Here, in the present embodiment, the vehicle height sensor 60 has a well-known structure that is installed in a well-known suspension control device that adjusts the vehicle height, and the G sensor 1 and the wheel speed sensor 30 also have a well-known structure. belongs to. Each modulator 50 is also a known type such as a hydraulic type or a pneumatic type in which the hydraulic fluid or pneumatic pressure is used to control the brake hydraulic pressure by the operation of the solenoid, or an electric type in which the brake hydraulic pressure is directly controlled by the operation of the solenoid. . By the way, when the controller 5 receives the high μ road signal from the G sensor 1 during braking, the high μ road anti-skid control means 64 and the low μ road signal for controlling the brake fluid pressure for the high μ road are provided. In case of receiving, the anti-skid control means 66 consisting of the low-μ road anti-skid control means 65 for performing the brake fluid pressure control for the low μ road, and the detection signal from the vehicle height sensor 60 at the time of brake ON A calculating means 62 for calculating the fluctuating frequency, and a comparing means for comparing the output from the calculating means with a predetermined value, and when the output is equal to or more than the predetermined value, sends a bad road signal as a bad road.
63, a high μ road signal generating means 69 for generating and sending a high μ road signal, and a switching for sending a road surface μ signal from the G sensor 1 to the anti-skid control means 66 when a bad road signal is received. It is a microcomputer configured to achieve the same function as the means 68, and further, a program capable of achieving the above function is written in the ROM in the controller 5, and each set value and data table are stored and processed. ROM
The program written in
It looks like Figure 2.

The operation of this device will be described below according to the program.

When the program starts, first in step 1, each sensor, that is, G sensor 1, wheel speed sensor 3
Read the output values from 0, the brake switch 40, and the vehicle height sensor 60, and proceed to step 2. In step 2, it is determined whether or not the brake switch 40 is on, that is, whether or not the brake pedal is depressed, and the pedal is depressed. If not, the process returns to step 1 and the same operation is repeated until it is depressed. If it is depressed, the process proceeds to step 3. In step 3, it is determined whether or not a slip wheel is present. If there is no anti-skid control, it is not necessary to perform anti-skid control, so return to step 1, while if there is a slip wheel, proceed to step 4, and in step 4, the detection signal of the vehicle height sensor 60, that is, the on / off signal or high / low signal. It is determined whether or not the fluctuating frequency calculated based on the switching of the signals is equal to or higher than a predetermined value. Here, the detection signal of the vehicle height sensor when traveling on a low μ road having a relatively high road surface resistance such as a corrugated road, a gravel road, an uneven road, and a ground road, that is, a bad road is a short cycle of an on-off signal or a high-low signal This is repeated, and at that time, that is, the frequency at the time of a rough road is set as a predetermined value. Therefore, if the calculated fluctuating frequency is equal to or higher than the predetermined value, it is determined that the road is a bad road, and the process proceeds to step 5. The anti-skid control for the high μ road, that is, the control for delaying the brake fluid pressure release timing in order to slightly lock the wheels is performed on the modulator, and then the process returns to step 1. The predetermined value referred to here is a value determined experimentally. On the other hand, if it is determined in step 4 that the road is not a bad road and the process proceeds to step 6, it is determined in step 6 whether or not the G sensor 1 is off. In step 5, anti-skid control for a high μ road is performed in step 5, and then the process returns to step 1, while it is on, that is, when traveling on a low μ road such as a snowy road which is not a bad road. Go to step 7 and step 7
In the low-μ road anti-skid control, that is, the control for advancing the brake fluid pressure release timing to prevent the wheel locking tendency from being advanced is performed on the modulator,
After that, the process returns to step 1.

As described above, in the present embodiment, during braking during traveling on a rough road, the anti-skid control for the high μ road is always performed regardless of the road μ signal of the G sensor, so that the braking is performed while maintaining the vehicle stability. The distance can be greatly reduced.

In the above embodiment, whether or not the vehicle is on a bad road is determined by obtaining the fluctuation frequency of the vehicle height sensor 60, which is the detection means equipped in the suspension control device. The well-known vertical G sensor 70 installed in the device
As shown in FIG. 1, it is of course possible to use the vehicle height sensor 60 instead of the vehicle height sensor 60 and determine the fluctuating frequency of the vertical G sensor 70 to determine whether or not the road is rough. In this way, if the vehicle height sensor or the vertical G sensor, which is the detection means equipped in the suspension control device, is diverted to this anti-skid control device, the cost can be reduced, but the anti-skid control device of the present invention is Needless to say, it can be applied to a vehicle not equipped with the suspension control device if a vehicle height sensor and a vertical G sensor are newly provided.

(Effect) As described above, according to the present invention, the fluctuation frequency of the detection signal according to the displacement of the vehicle height when the brake is turned on is calculated, and when the calculated value is equal to or higher than a predetermined value that can be regarded as a rough road, braking is performed. Sometimes high μ
Since I made it possible to control the brake fluid pressure for the road,
It is possible to significantly reduce the braking distance while maintaining vehicle stability when braking on rough roads.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of an anti-skid control device showing an embodiment of the present invention, and FIG. 2 is a flow chart of a program stored in the controller shown in FIG. 1 ... G sensor, 5 ... controller, 30 ... wheel speed sensor, 40 ... brake switch, 50 ... modulator, 60 ... vehicle height sensor, 62 ... calculation means, 63 ... comparison means, 64 ... … Anti-skid control means for high μ road, 65 …… Anti-skid control means for low μ road, 66 …… Anti-skid control means, 68 …… Switching means, 69 …… High μ road signal generating means, 70 …… Up and down G sensor.

Claims (1)

[Scope of utility model registration request] 1. A wheel speed sensor that detects each wheel speed of a vehicle and sends out a speed signal corresponding to the wheel speed, a high μ road signal when the vehicle has a high acceleration / deceleration, and a low μ when the vehicle has a low acceleration / deceleration. Each of the wheels has a G sensor that sends out a road signal, a brake switch that detects ON / OFF of the brake, and a modulator that controls the brake fluid pressure in the brake pipe. In the locked state, when the high μ road signal is received, the brake fluid pressure control for the high μ road is performed by the high μ road anti-skid control means, and when the low μ road signal is received, the low μ road signal is low. An anti-skid control device having anti-skid control means for preventing the brake fluid pressure control for low μ roads by the road anti-skid control means, in accordance with a displacement of the vehicle height of the vehicle. Detection means for transmitting a signal,
A calculation unit that calculates the fluctuation frequency of the detection signal when the brake is turned on is compared with an output from the calculation unit and a predetermined value. If the output is equal to or more than the predetermined value, it is determined that the road is a bad road. A comparison means for transmitting a signal, a high μ road signal generating means for generating and transmitting a high μ road signal, and a high road signal from the G sensor instead of the road μ signal when the bad road signal is received. An anti-skid control device comprising a controller comprising a switching means for sending a high-μ road signal from the μ road signal generating means to the anti-skid control means.