JPH065929Y2 - 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 control 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. 58-47381. Are known from.

(Problems to be solved by the invention) Here, the vehicle equipped with the anti-skid control device corresponds to 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 driving on a road surface with a low friction coefficient (hereinafter referred to as a bad road) that strongly gives a shock, the road surface resistance is high unlike the snow road 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 transmitted from the G sensor. Therefore, the anti-skid control for the low μ road, that is, the brake fluid pressure is immediately increased. The control to pull it out was made, and as a result, the braking distance was greatly extended, which was even dangerous.

An object of the present invention is to provide an anti-skid control device having excellent vehicle stability capable of shortening a braking distance 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. It is in.

(Means for Solving Problems) In order to achieve the above object, the anti-skid control device of the present invention calculates the hunting frequency of the on / off signal of the G sensor when the brake is off, and the calculating means. Comparing the output with a predetermined value, and when the output is greater than or equal to the predetermined value, comparing means for sending a bad road signal as a bad road,
A high μ road signal generating means for generating and transmitting an OFF signal, and a high μ road signal generation instead of the ON / OFF signal from the G sensor when the brake ON signal is received after receiving the bad road signal. It is characterized in that the controller comprises a switching means for sending an off signal from the means to the anti-skid control means.

(Operation) According to the present invention, the on / off signal from the G sensor is input to the calculating means, and the calculating means calculates the G when the brake is off.
The hunting frequency of the on / off signal of the sensor is calculated, and the hunting frequency is input to the comparison means. When the hunting frequency is equal to or higher than a predetermined value that the comparison means can regard as a bad road, the bad road signal is input to the switching means. To be done. On the other hand, when the brake signal is also input to the switching means and the brake on signal is received after the bad road signal is received, the off signal from the high μ road signal generating means is replaced with the off signal from the high μ road signal generating means instead of the on / off signal from the G sensor. The brake fluid pressure control for the high μ road is performed by the anti-skid control means for the high μ road.

Embodiment An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a configuration of an anti-skid control device showing an embodiment of the present invention, and FIG. 2 is a schematic diagram of a G sensor, a calculation means, and a comparison means specifically showing a main part of the same device. As shown in FIG. 1, the anti-skid control device of the present invention includes a G sensor 1 for transmitting 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 a vehicle Each wheel speed is detected, a wheel speed sensor 30 that sends out a speed signal corresponding to the wheel speed, a brake switch 40 that detects the operation of the brake pedal and sends out its on / off signal, and a brake fluid pressure of each wheel In response to the signals from the respective modulators 50 for controlling, the G sensor 1, the wheel speed sensor 30, and the brake switch 40,
Controller 5 that sends a drive signal to each modulator 50
It has and. Here, the wheel speed sensor 30 has a well-known structure, and each modulator 50 also has a hydraulic fluid or pneumatic system in which brake fluid pressure is controlled by using hydraulic pressure or pneumatic pressure by operating a solenoid, or a brake fluid by operating a solenoid. It is a known type such as an electric type which directly controls the pressure. On the other hand, in the G sensor 1, as shown in FIG. 2, a casing 2 made of resin or metal is formed in the casing 2, and rises in the front-rear direction of the vehicle (left-right direction in the figure), and is located at the bottom in the approximate center. Inclined groove 2b with point 2a
And the anti-skid control means arranged in the inclined groove 2b along the inclined groove 2b, one base end of which is the plus current 6 and the other end of which is the change-over switch 68 which is a change-over means in the controller 5. Reed switches 3 respectively connected to 66 and located in the vicinity of the lowermost point 2a in the inclined groove 2b with one end 3b and the other proximal end 3c in a non-contact state, and in the inclined groove 2b. It is composed of a mercury ball 4 as a conductive liquid particle to be enclosed. When braking on a high μ road, the road surface resistance is high and the deceleration is large, and the mercury ball 4 is inclined due to inertial force. As it rises inward, the reed switch 3 is released from the energized state. On the other hand, at the time of braking during low μ road traveling, the road surface resistance is low and the deceleration is small. As shown by the solid line at the lowest point 2a in Since it stops, the reed switch 3 is energized. As described above, since the reed switch 3 is turned off during braking during traveling on a high μ road, the G sensor 1 does not energize the controller 5 side, while the reed switch 3 is turned on during braking during traveling on a low μ road. Since it is turned on, an on signal is sent from the G sensor 1 to the controller 5 side. In addition, the above-mentioned bad roads, that is, wavy roads, gravel roads, uneven roads,
When traveling on a low μ road with a relatively high road surface resistance such as a ground road, since the vertical acceleration / deceleration of the vehicle is large, the end side of the above-mentioned bifurcated inclined groove 2b and the lowest point 2a are In the meantime, the mercury ball 4 moves up and down violently, the mercury ball 4 rises upward to turn off the G sensor 1, and the mercury ball 4 returns to the vicinity including the lowest point 2a to turn the G sensor 1 on. Turning on is continuously repeated in a short cycle. That is, an on / off signal having a short cycle, that is, a so-called hunting signal is sent to the controller 5 side. On the other hand, it's not a bad road, low μ
When traveling on a road or a high μ road, that is, a snow road, a paved road, etc., the acceleration / deceleration in the vertical direction of the vehicle is small.
Sensor 1 remains on, controller 5
ON side signal is always sent to the side, or even if the acceleration / deceleration is sometimes large, the frequency is low, so whether the controller 5 side sends an ON / OFF signal having a relatively long cycle. Will be either. As described above, the signal from the G sensor 1 is the information at the time of brake-on whether the road surface is the high μ road or the low μ road, and the brake off whether the road surface is the bad road or the bad road. It has time information.

On the other hand, when the controller 5 receives the OFF signal from the G sensor 1 when the brake switch 40 is ON, it receives the high μ road anti-skid control means 64 for performing the brake fluid pressure control for the high μ road and the ON signal. Low μ
Anti-skid control means 66 consisting of low-μ road anti-skid control means 65 for performing brake fluid pressure control for roads
And a calculation means 62 for calculating the hunting frequency of the on / off signal of the G sensor 1 when the brake switch 40 is off, and the output from the calculation means 62 is compared with a predetermined value. Comparing means 63 for sending a bad road signal as a bad road, high μ road signal generating means 69 for generating and sending an off signal, and an on signal from the brake switch 40 after receiving the bad road signal If received, G sensor 1
It is a microcomputer configured to achieve the same function as the switching means 68 for sending the OFF signal from the high μ road signal generating means 69 to the anti-skid control means 66 instead of the ON / OFF signal from. Here, the calculation means 6
2, the comparison means 63, etc. are specifically the second
It is configured as shown in the figure. That is, G sensor 1
The output side terminal of the changeover switch 68 is connected to the changeover switch 68, one output terminal of the changeover switch 68 is the anti-skid control means 66, and the other terminal is the calculation means F / V converter 6
2 are connected to each other, and the output terminal of the F / V converter 62 is connected to one input terminal of the comparator 39. On the other hand, comparator
The other input terminal of 39 has a specified voltage of 10 when driving on a rough road.
Is applied to the output terminal of the comparator 39
The pre-comparator 39 and the predetermined value voltage 10 are connected to 68, and constitute a comparison means 63. A program capable of achieving the above functions is written in the ROM in the controller 5 configured as described above, and each set value and data table are stored. The program written in the ROM is shown in the flowchart of FIG.

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

When the program starts, first the flag is set to 0 in step 1, and the process proceeds to step 2 and step 2
Then, each sensor, G sensor 1, wheel speed sensor
30. Read the output value from the brake switch 40 and proceed to step 3. In step 3, it is determined whether or not the brake switch 40 is on, that is, whether or not the brake pedal is depressed, and if it is depressed. If it is not stepped on, the process proceeds to step 5. In step 5, the hunting frequency of the G sensor is calculated based on the switching of the on / off signal from the G sensor, and the process proceeds to step 6 and in step 6. , It is determined whether the hunting frequency is equal to or higher than a predetermined value. Here, the ON / OFF signal of the G sensor when traveling on a high 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 repetition of the ON / OFF signal having a short cycle as described above. At that time, that is, the frequency at the time of a bad road is set as a predetermined value, and if the calculated hunting 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 7 and the flag is set at step 7. Is set to 1 and then returns to step 2. On the other hand, if it is smaller than the predetermined value, it is determined that the road is not a bad road, the process proceeds to step 8, the flag is set to 0 in step 8, and then the process returns to step 2. The predetermined value referred to here is a value determined experimentally. When returning to step 2, the process proceeds to step 2 and step 3 as described above, and if it is determined in step 3 that the brake switch 40 is on, that is, the brake pedal is depressed, the process proceeds to step 4 and the step In No. 4, it is determined whether or not there is a slip wheel. If there is no slip wheel, it is not necessary to perform anti-skid control, so the process returns to Step 2.
On the other hand, if there are slip wheels, proceed to step 9,
In step 9, it is determined whether the above-mentioned flag is 0, that is, whether the road is a bad road. If the flag is 0 here,
If it is not a bad road, proceed to step 11. If the flag is not 0, that is, if it is 1, it is a bad road and step.
In step 10, the anti-skid control for the high μ road, that is, the control for delaying the brake fluid pressure release timing to slightly lock the wheels is performed on the modulator, and then the process returns to step 2. On the other hand, if it is determined in step 9 that the road is not a bad road and the process proceeds to step 11, it is determined in step 11 whether or not the G sensor 1 is off. If it is off, that is, if the road is a high μ road that is not a bad road such as a paved road. In step 10, the anti-skid control for the high μ road is performed in step 10, and then the process returns to step 2, while it is on, that is, when the road is a low μ road such as a snowy road which is not a bad road. Go to step 12 and low μ
The anti-skid control for the road, that is, the control for advancing the brake fluid pressure release timing in order to prevent the locking tendency of the wheels from being advanced, is performed on the modulator, and then the process returns to step 2.

As described above, according to the present invention, the anti-skid control for the high μ road is always performed regardless of the road μ signal of the G sensor at the time of braking during traveling on a bad road, so that the vehicle stability is maintained, The braking distance can be greatly shortened.

The G sensor 1, the calculating means 62, and the comparing means 63 of the above embodiment
Is not limited to that shown in FIG. 2, but various modifications are possible.

(Effect) As described above, according to the present invention, the hunting frequency of the on / off signal of the G sensor when the brake is off is calculated, and when the calculated value is equal to or higher than the predetermined value that can be regarded as a bad road, the high μ road is used during braking. Since the brake fluid pressure control for the vehicle is performed, it is possible to significantly reduce the braking distance while maintaining the vehicle stability during braking on rough roads.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an anti-skid control device showing an embodiment of the present invention, and FIG. 2 is a schematic diagram of a G sensor, a calculation means, and a comparison means for specifically showing a main part of the same device,
FIG. 3 is a flowchart of a program stored in the controller shown in FIGS. 1 and 2. 1 ... G sensor, 5 ... controller, 30 ... wheel speed sensor, 40 ... brake switch, 50 ... modulator, 62 ... calculating means, 63 ... comparing means, 64 ... high μ road anti-skid Control means, 65: anti-skid control means for low μ road, 66: anti-skid control means, 68: switching means, 69: high μ road signal generating means.

Claims (1)

[Scope of utility model registration request] 1. A G sensor that sends an off signal when the vehicle is in high longitudinal acceleration / deceleration direction and a high acceleration / deceleration direction in the vertical direction, and an on signal when the vehicle is low acceleration / deceleration, and each wheel speed is detected and a speed signal corresponding to the wheel speed. A wheel speed sensor for sending out, a brake switch for detecting ON / OFF of the brake, and a modulator for controlling the brake fluid pressure of the brake pipe, respectively, and the lock state of each wheel at the time of braking detected based on the speed signal. When the OFF signal is received during braking, the brake fluid pressure control for the high μ road is performed by the anti-skid control means for the high μ road, and when the ON signal is received during braking, the low μ In an anti-skid control device having anti-skid control means for preventing each by low-μ road brake fluid pressure control by the road anti-skid control means, A calculating means for calculating the hunting frequency of the on / off signal of the G sensor when the brake is off is compared with an output from the calculating means and a predetermined value. If the output is equal to or more than the predetermined value, it is regarded as a bad road. A comparing means for transmitting a road signal, a high μ road signal generating means for generating and transmitting an off signal, and a on signal from the G sensor when a brake on signal is received when the bad road signal is received. An anti-skid control device comprising a controller comprising switching means for sending an OFF signal from the high μ road signal generating means to the anti-skid control means instead of the signal.