JP2976440B2 - Anti-skid control device - Google Patents

Description

The present invention relates to an anti-skid control device.

[Prior Art] Conventionally, in an anti-skid control device, the brake fluid of the brake device is drained to a reservoir due to the tendency of the wheels to lock, and the brake fluid recovery motor is driven at the timing of the start of pressure reduction to return the brake fluid to the master cylinder side. Was. Also, when the pressure is reduced, the liquid remaining in the reservoir is discharged for a certain time,
The brake fluid recovery motor was driven, and then the motor was stopped. However, in these methods, a state occurs in which the motor is driven even after the vehicle stops, and there is a problem of vehicle interior noise. To solve such a problem,
No. 209944 discloses that the brake fluid recovery motor uses a wheel speed of 0 km / h.
It is proposed to stop at.

[Problems to be Solved by the Invention] Even if the motor for recovering the brake fluid is not driven when the vehicle is stopped as in the related art, the brake fluid remains in the motor for recovering the brake fluid, and the anti-kid control is performed. May be prevented from being executed reliably.

Accordingly, it is an object of the present invention to reduce noise generated by pump driving due to driving of a motor during anti-skid control and to enable reliable anti-skid control.

[Means for solving the problem]

According to the present invention, as shown in FIG. 1 corresponding to the configuration of claim 1, the brake fluid of the wheel cylinder is supplied when the pressure reduction mode is set during the anti-skid control performed based on the signal of the wheel speed sensor M1. Decompression means M2 drawn into the reservoir
And a motor M3 that is driven in accordance with the anti-skid control and drives a pump that pumps up the brake fluid in the reservoir. The first motor that stops the driving of the motor M3 when it is determined that the vehicle speed is running at a predetermined speed or less based on the signal of the wheel speed sensor M1 during the anti-skid control that drives the motor M3 Control means M4, and a second means for driving the motor M3 after the execution of the first motor control means M4 and when the anti-skid control is not being performed.
And a motor control means M5.

[Action]

In the brake fluid pressure control device according to the first aspect, when the brake fluid pressure applied to the wheel cylinder is increased or decreased or maintained and the pressure reduction mode is set during the anti-skid control for driving the pump, the pressure of the wheel cylinder is reduced by the pressure reducing means M2. The brake fluid is drained into the reservoir, and the motor M3 is driven during this brake fluid decompression operation. At this time, the first motor control means M4 stops driving the motor M3 when it determines that the vehicle speed is running at a predetermined speed or less based on the signal of the wheel speed sensor M1.

Also, the second motor control means M5, after the execution of the first motor control means, and when not in anti-skid control, the vehicle speed is equal to or higher than a predetermined speed based on the signal of the wheel speed sensor M1, When it is determined that the motor is stopped, the motor M3 is driven. Therefore, at the time of the next anti-skid control, the brake fluid in the reservoir is collected in the master cylinder.

Therefore, it is possible to surely reduce the noise caused by driving the pump, and it is possible to appropriately avoid a state in which the storage capacity of the reservoir is reduced and an appropriate decompression operation is not performed.

Also in the brake fluid pressure control device according to the second aspect of the present invention, the motor is not driven at least in the stop state of the vehicle when the vehicle is stopped from the execution state of the anti-skid control. The second motor control means drives the motor in a state in which the vehicle is running at a predetermined speed or more from a stopped state of the vehicle and in a state in which the anti-skid control is not being performed. Therefore, the driving noise of the motor and the pump in the vehicle stopped state where the noise is most worrisome is
The brake fluid remaining in the reservoir can be reliably suppressed even when the motor is driven to return to the master cylinder side, and the reservoir for collecting the brake fluid in a state after the start of traveling and before the anti-skid control is started. Therefore, it is possible to accurately prevent the decompression operation from being performed in the anti-skid control.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

In FIG. 2, the vehicle is provided with a right front wheel 1, a left front wheel 2, a right rear wheel 3, and a left rear wheel 4. Near the right front wheel 1, a right front wheel speed sensor 5 is attached, and the sensor 5 generates a signal according to the rotation of the right front wheel 1. A front left wheel speed sensor 6 is mounted near the front left wheel 2 and generates a signal corresponding to the rotation of the front left wheel 2. Propeller shaft 8 for transmitting power to right rear wheel 3 and left rear wheel 4 as drive wheels
Is mounted with a rear wheel speed sensor 7 which generates a signal corresponding to the rotation of the propeller shaft 8 corresponding to the average rotation speed of the right rear wheel 3 and the left rear wheel 4. As these wheel speed sensors 5 to 7, an electromagnetic pickup type or photoelectric conversion type wheel speed sensor is used.

The right front wheel 1 has a wheel cylinder 9 of a braking device.
The left front wheel 2 has a wheel cylinder 10, the right rear wheel has a wheel cylinder 11, and the left rear wheel 4 has a wheel cylinder 12
Are arranged respectively. A stop switch 14 is provided on the brake pedal 13, and the switch 14 detects the time of braking and the time of non-braking according to the operation state of the brake pedal 13. The brake device master cylinder 15 is a brake pedal
When 13 is depressed, brake fluid pressure is generated. The actuators 16, 17, and 18 as adjusting means adjust the hydraulic pressure from the master cylinder 15 according to a signal from an electronic control circuit 25 to be described later and send the adjusted hydraulic pressure to the wheel cylinders 9 to 12. Among them, the right front wheel actuator 16 corresponds to the wheel cylinder 9 of the right front wheel 1, the left front wheel actuator 17 corresponds to the wheel cylinder 10 of the left front wheel 2, and the rear wheel actuator 18 is the wheel cylinders 11, 12 of the rear wheels 3, 4. Corresponding to

The hydraulic lines 19, 20, 21, and 22 are for guiding the adjusted hydraulic pressure from the actuators 16 to 18 to the wheel cylinders 9 to 12. The hydraulic line 19 is the right front wheel actuator 16
And a hydraulic line provided between the right front wheel 1 and the wheel cylinder 9. The hydraulic line 20 is a hydraulic line provided between the left front wheel actuator 17 and the wheel cylinder 10 of the left front wheel 2. . The hydraulic line 21 is a hydraulic line provided between the rear wheel actuator 18 and the wheel cylinder 11 of the right rear wheel 3, and the hydraulic line 22 is a wheel cylinder of the rear wheel actuator 18 and the left rear wheel 4. 12 is a hydraulic pressure line provided between the hydraulic pressure control device and the pressure control device.

The main relay 23 performs connection between the electromagnetic solenoids of the actuators 16 to 18 and the power supply according to the output of the electronic control circuit 25. The indicator lamp 24 notifies the driver of the occurrence of an abnormality in the system according to the output of the electronic control circuit 25 when a failure occurs in the anti-skid control device such as when the electromagnetic solenoid is disconnected or when the stop switch 14 is disconnected.

The electronic control circuit 25 receives signals from the wheel speed sensors 5 to 7 and the stop switch 14, performs arithmetic processing for anti-skid control, and controls the actuators 16 to 18, the main relay 23 and the indicator lamp 24. Occurs.

Above right front wheel actuator 16, left front wheel actuator
17 and the rear wheel actuator 18, as shown in FIG.
An electromagnetic solenoid unit 26 and a reservoir motor unit 27 are provided. The electromagnetic solenoid unit 26 switches the brake fluid pressure to a mode of increasing, decreasing, or holding. Further, the reservoir motor unit 27 is provided with a reservoir and a brake fluid recovery motor. When the brake fluid pressure decreases, the brake fluid (brake fluid) is temporarily stored in the reservoir, and thereafter, the brake fluid is recovered. The pump (not shown) is operated by driving the motor for use, and the brake fluid is returned to the master cylinder 15 side.

The hydraulic pressure output from each of the actuators 16 to 18 is transmitted to each of the wheel cylinders 9 to 12 via each of the hydraulic lines 19 to 22 to brake the wheels 1 to 4. or,
The electromagnetic solenoids of the actuators 16 to 18 are adapted to reduce, for example, the fluid pressure when energized.

FIG. 4 shows an electrical configuration of the anti-skid control device centering on the electronic control circuit 25. Microcomputer as determination means, pump control means, decompression means, and first and second motor control means, which are main parts of electronic control circuit 25
28 includes a CPU 29, a ROM 30, a RAM 31, an I / O circuit 32, and the like. The waveform shaping amplifier circuit 33 converts the signal of the wheel speed sensor 5 into a pulse signal suitable for processing by the microcomputer 28, and the waveform shaping amplifier circuits 34 and 35 also generate similar pulse signals to the signals of the wheel speed sensors 6 and 7, respectively. It is configured as follows. The buffer circuit 36 is electrically connected to the stop switch 14, and the power supply circuit 37 supplies a constant voltage to the microcomputer 28 and the like when the ignition switch 38 is turned on.

The right front wheel actuator drive circuit 39 drives the electromagnetic solenoid of the right front wheel actuator 16 and the brake fluid recovery motor, and the left front wheel actuator drive circuit 40 drives the electromagnetic solenoid of the left front wheel actuator 17 and the brake fluid recovery motor, and the rear wheel The actuator drive circuit 41 drives the electromagnetic solenoid of the rear wheel actuator 18 and the brake fluid recovery motor. The main relay drive circuit 42 is a normally open relay contact.
The relay coil 23b of the main relay 23 having 23a is energized to close the normally open contact 23a. The indicator lamp drive circuit 43 turns on the indicator lamp 24. Each drive circuit
Reference numerals 39 to 43 perform outputs in accordance with control signals from the microcomputer 28, respectively.

Next, the operation of the anti-skid control device thus configured will be described.

FIG. 5 shows a schematic flowchart of the anti-skid control, and FIG. 6 shows a time chart for explaining the anti-skid control of the present embodiment.

First, the CPU 29 performs initialization for processing described later only at the start of processing in step 100. For example, resetting of a flag to be described later, or the like. In step 200, the CPU 29 reads the outputs of the wheel speed sensors 5 to 7, the signal of the stop switch 14, and the like. In step 300, the CPU 29 calculates the actual wheel speed based on the output values of the wheel speed sensors 5 to 7 in step 200, and obtains the wheel acceleration from the amount of change in the wheel speed. Further, the CPU 29 proceeds to step 400 in step 30.
Using the wheel speed at zero, an estimated vehicle body speed Vs is created.

Then, in step 500, the CPU 29 determines the slip state by comparing the speed of each wheel with the estimated vehicle speed Vs in step 400, and also determines whether the wheels tend to lock or return according to the sign of the wheel acceleration. To determine whether or not to perform anti-skid control.
When the anti-skid control is performed, the CPU 29 operates the actuators 16 to 18 (pressure increasing, holding, and pressure decreasing modes).
Make a selection. In step 600, the CPU 29 actually selects the actuator 16 based on the result of the mode selection in step 500.
Outputs signals for driving ~ 18 electromagnetic solenoids. Thereafter, the CPU 29 turns on and off the brake fluid recovery motors of the actuators 16 to 18 in step 700 according to the operation mode in step 500.

FIG. 7 is a flow chart for explaining the motor driving process in step 700.

The CPU 29 determines in step 701 whether or not the anti-skid control is being performed.
In step 2, the estimated vehicle speed Vs is changed to a predetermined speed KV1 (for example,
10km / h) is determined. And CPU29
Is larger (Vs> KV1), the brake fluid recovery motor is driven in step 703, and if smaller (Vs ≦ KV1), the brake fluid recovery motor is stopped in step 704 and discharged by the subsequent control. The brake fluid is stored in the reservoir of the reservoir motor unit 27. Thereafter, in step 705, the CPU 29 sets a request flag FMT (FMT = 1) for requesting recovery of the brake fluid during traveling.

If the anti-skid control is not being performed in step 701, the CPU 29 sets the request flag FMT in step 706 (FMT).
= 1), it is determined whether or not the stop switch 14 has been turned off without stepping on the brake pedal 13 in step 707 if it has been set. If the brake pedal 13 is not depressed, the CPU 29 determines in step 708 whether or not the estimated vehicle speed Vs is higher than a predetermined speed KV2 (for example, 6 km / h). In 709, the brake fluid recovery motor is driven for a predetermined time T1.

Thereafter, the CPU 29 resets the request flag FMT in step 710 (FMT = 0).

As a result, as shown in FIG. 6, during the anti-skid control, when the estimated vehicle speed Vs falls below the predetermined speed KV1 (at timing t7 in FIG. 6), the drive of the brake fluid recovery motor is stopped. When the anti-skid control is not being performed and the estimated vehicle speed Vs becomes equal to or higher than the predetermined speed KV2 (timing t10 in FIG. 6), the driving of the brake fluid recovery motor is started and the motor is driven for a predetermined time T1. Is performed.

In the driving signal of the motor in FIG. 6, the broken line for comparison shows the operation when the driving of the brake fluid recovery motor is continued irrespective of the decrease in the estimated vehicle speed Vs. In FIG. 6, the pressure reduction of the brake fluid is t1-t2, t3-t4, t5-t6, t
It is performed at each timing of 8 to t9.

As described above, in this embodiment, when the anti-skid control is being performed and the vehicle speed (estimated vehicle speed Vs) is determined to be equal to or lower than the predetermined speed KV1 based on the signals of the wheel speed sensors 5 to 7, the brake fluid recovery is performed. When the anti-skid control is not being performed while the driving of the
When it is determined that the vehicle speed is equal to or higher than the predetermined speed KV2 and after the above-described motor stop has been performed based on the signals of (7) to (7), the brake fluid recovery motor is driven. As a result, conventionally, the brake fluid recovery motor
If stopped at m / h, the brake fluid will remain in the reservoir, which will cause the first anti-skid control to cause a decompression failure at the first time, and may also prevent the noise of the anti-skid control when the sound in the cabin at low speed is quiet. However, if there was no such situation and the vehicle speed (estimated vehicle speed Vs) became equal to or lower than the predetermined speed KV1, the driving of the brake fluid recovery motor was stopped, and braking was performed at a predetermined speed KV2 or higher that was not under anti-skid control. The liquid recovery motor is driven to recover the brake liquid for the next anti-skid control. Therefore, it is possible to reduce the noise generated when the brake fluid is collected, and to reliably perform the anti-skid control.

[Effects of the Invention] As described in detail above, according to the first and second aspects of the present invention, it is possible to reduce the noise generated at the time of collecting the brake fluid and to reliably perform the anti-skid control. It is effective.

[Brief description of the drawings]

FIG. 1 is a claim correspondence diagram, FIG. 2 is an overall configuration diagram of the anti-skid control device of the embodiment, FIG. 3 is a diagram showing an actuator, FIG. 4 is an electric circuit diagram of the anti-skid control device, and FIG. FIG. 6 is a flow chart, FIG. 6 is a time chart for explaining the operation, and FIG. 7 is a flow chart. M1 is a wheel speed sensor, M2 is a pressure reducing means, M3 is a brake fluid recovery motor, M4 is a first motor control means, and M5 is a second motor control means.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B60T 8/58 B60T 8/48

Claims (4)

(57) [Claims] 1. A pressure reducing means for draining brake fluid from a wheel cylinder into a reservoir when a pressure reducing mode is set during an anti-skid control performed based on a signal from a wheel speed sensor; A motor that drives a pump that pumps the brake fluid; anda brake fluid pressure control device comprising: a brake fluid pressure applied to the wheel cylinder is increased or decreased, or is under anti-skid control in which the pump is driven, And first motor control means for stopping the driving of the motor when it is determined that the vehicle speed is running at a predetermined speed or less based on the signal of the wheel speed sensor, and after execution of the first motor control means. And second motor control means for driving the motor when the anti-skid control is not being performed. Brake fluid pressure control apparatus according to symptoms. 2. A pressure reducing means for draining brake fluid from a wheel cylinder into a reservoir when a pressure reducing mode is set during anti-skid control performed based on a signal from a wheel speed sensor; A motor that drives a pump that pumps the brake fluid; anda brake fluid pressure control device comprising: a brake fluid pressure applied to the wheel cylinder is increased or decreased, or is under anti-skid control in which the pump is driven, And first motor control means for stopping the driving of the motor when it is determined that the vehicle speed is equal to or less than a predetermined speed based on the signal of the wheel speed sensor, and after execution of the first motor control means, And second motor control means for driving the motor while the vehicle is not in anti-skid control. Brake fluid pressure control apparatus according to claim. 3. The second motor control means executes the driving of the motor before the next anti-skid control is started after the anti-skid control is executed by the first motor control means. 3. The brake fluid pressure control device according to claim 1, wherein 4. A stop switch indicating whether or not an occupant depresses a brake pedal is temporarily turned off after the anti-skid control is executed by the first motor control means. The brake fluid pressure control device according to any one of claims 1 to 3, wherein the drive of the motor is performed later.