JP2002067910A - Vehicle braking control device - Google Patents

Abstract

(57) [Problem] To provide a vehicle brake control device having an automatic pressurizing function of a master cylinder pressure capable of accurately determining a driver's operation of a brake pedal. SOLUTION: A master cylinder pressure which is automatically pressurized and controlled is supplied to wheel cylinders 13 to 16 of each wheel to control a braking force of the wheel. This master cylinder pressure is detected by a hydraulic pressure sensor 62. Based on the detected master cylinder pressure, the master cylinder pressure change speed d
Pmc is calculated. In the VSC control, an integral value idPmc of the master cylinder pressure change speed from the time when the master cylinder pressure change speed dPmc becomes negative is calculated, and a braking state determination threshold value in which the integral value idPmc is a predetermined positive number is calculated. When KS2 is exceeded, it is determined that the brake pedal is in the operating state.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic pressurizing control of a master cylinder pressure, and a control of supplying a master cylinder pressure under the automatic pressurizing control to a wheel cylinder of each wheel to control a braking force of the wheel. The present invention relates to a vehicle brake control device.

[0002]

2. Description of the Related Art Conventionally, as a vehicle brake control device of this type, for example, German Patent Publication DE 197070376A
No. 1 is known. The device described in the publication, for example, when performing vehicle stability control, even in a state where the driver does not operate the brake pedal, automatically pressurizes the master cylinder pressure according to the vehicle state at that time It is possible to control the supply of the master cylinder pressure controlled by the automatic pressurization to the wheel cylinder of each wheel to control the braking force of the wheel. Thereby, the stability of the vehicle in the lateral direction at the time of turning or the like can be secured.

[0003]

In such a vehicle brake control device, it is necessary to control the braking force of each wheel so that the operation of the driver's brake pedal is reflected on the vehicle body deceleration. Therefore, it is necessary to accurately determine the operation state of the driver's brake pedal.

[0004] Such a determination of the driver's operation of the brake pedal is generally made by a stop lamp switch which is turned on when the brake pedal is depressed. However, in a state in which the master cylinder pressure controlled by the automatic pressurization is supplied to the wheel cylinder of each wheel, in order to maintain the braking force of the required wheel, the master cylinder pressure applied to the wheel cylinder of the wheel is controlled. Supply may be interrupted. In this case, since the stroke (depression) of the brake pedal is restricted, there is a possibility that the brake pedal cannot be depressed until the stop lamp switch is turned on. Therefore, it is desired to accurately determine the driver's operation state of the brake pedal even during such control.

SUMMARY OF THE INVENTION An object of the present invention is to provide a vehicle brake control device having an automatic master cylinder pressure pressurizing function capable of accurately determining a driver's operation of a brake pedal.

[0006]

In order to solve the above-mentioned problems, the invention according to claim 1 comprises an automatic pressurizing control means for automatically pressurizing a master cylinder pressure, and an automatic pressurizing control means for controlling the automatic pressurizing. A brake control device for a vehicle, comprising: braking force control means for controlling a braking force of each wheel by controlling a supply of a master cylinder pressure to a wheel cylinder of each wheel; a pressure detecting means for detecting the master cylinder pressure; A master cylinder pressure change speed calculating means for calculating a change speed of the master cylinder pressure based on the master cylinder pressure, and the automatic pressurizing means controlling the master cylinder pressure in an automatic pressurizing manner. A change speed integral value calculating means for calculating an integral value of the master cylinder pressure change speed from the time when the master cylinder pressure change speed becomes negative; When the integrated value of Sunda pressure change rate exceeds the braking state determination threshold value, and summarized in that and a pedal operation determining means determines that the operation state of the brake pedal.

According to a second aspect of the present invention, there is provided an automatic pressurizing control means for automatically pressurizing a master cylinder pressure, and supplying and controlling the master cylinder pressure controlled by the automatic pressurizing to a wheel cylinder of each wheel. A vehicle braking control device comprising: a braking force control unit that controls a braking force of a wheel; a pressure detection unit that detects the master cylinder pressure; and a change speed of the master cylinder pressure based on the detected master cylinder pressure. Master cylinder pressure change speed calculating means for calculating;
In a state in which the automatic pressurizing means is performing automatic pressurization control of the master cylinder pressure, after a lapse of the braking state determination prohibition time from the time when the calculated master cylinder pressure change speed falls below the first braking state determination threshold value. And a pedal operation determining means for determining that the brake pedal is operating when the master cylinder pressure change speed exceeds the second braking state determination threshold value.

[0008] The invention according to claim 3 is the invention according to claim 1 or 2.
The vehicle brake control device according to claim 1, wherein the calculated master cylinder pressure change speed falls below a non-braking state determination threshold value in a state in which the automatic pressurizing unit is performing automatic pressurizing control of a master cylinder pressure. The invention further comprises pedal operation determination canceling means for canceling the operation state determination of the brake pedal by the pedal operation determining means when the non-braking state determination prohibition time has continued.

According to a fourth aspect of the present invention, in the vehicle braking control apparatus according to the first aspect, the state in which the calculated integral value of the master cylinder pressure change speed falls below the non-braking state determination threshold value is determined. When the braking state determination prohibition time continues,
The gist of the present invention is to include a pedal operation determination canceling unit for canceling the determination of the operation state of the brake pedal by the pedal operation determining unit.

According to a fifth aspect of the present invention, in the vehicle braking control device according to the second aspect, the automatic pressurizing means controls the master cylinder pressure automatically.
A change speed integral value calculating means for calculating an integral value of the master cylinder pressure change speed from the time when the calculated master cylinder pressure change speed becomes negative; and an integrated value of the calculated master cylinder pressure change speed. When the state below the non-braking state determination threshold continues for the non-braking state determination prohibition time,
The gist of the present invention is to include a pedal operation determination canceling unit that cancels the determination of the operation state of the brake pedal by the pedal operation determining unit.

(Operation) In general, a vehicular braking system in which the master cylinder pressure is automatically pressurized and the master cylinder pressure controlled by the automatic pressurization is supplied to the wheel cylinder of each wheel to control the braking force of the wheel. In the control device, the speed of change (dPmc) of the master cylinder pressure in a state where the master cylinder pressure is under automatic pressure control (for example, during vehicle stability control).
Have been confirmed by the applicants to show a transition as shown in the time chart of FIG. 4 (a) or FIG. 6 (a), for example.

That is, since the master cylinder pressure controlled by the automatic pressurization is basically controlled to a required pressure, the rate of change thereof is maintained at the value "0". Then, when the supply of the master cylinder pressure to the wheel cylinders of the required wheels is newly started according to the control state, the master cylinder pressure is temporarily reduced by the supply and then automatically increased. As a result, the master cylinder pressure is increased (recovered). Correspondingly, the change speed of the master cylinder pressure temporarily becomes a negative number, then reverses to a positive number, and returns to the state of value “0”. The degree of change of the change speed of the master cylinder pressure, that is, the degree of reduction or increase of the change speed, and the time until recovery show substantially unique characteristics according to the capability of the device.

[0013] In addition, when the driver operates the brake pedal instead of supplying the master cylinder pressure to the wheel cylinders of the required wheels, the master cylinder pressure is increased by the amount corresponding to the depression. Correspondingly, the rate of change of the master cylinder pressure temporarily returns to a positive value, and then returns to the state of value “0”.

Further, when the operation state of the brake pedal by the driver is released, the master cylinder pressure is reduced accordingly. Correspondingly, the change speed of the master cylinder pressure becomes a negative number, but at this time, it shows a relatively small and redundant fluctuation characteristic.

Therefore, the operation state and the release state of the brake pedal by the driver can be detected by considering the respective transitions (variation characteristics) of the change speed of the master cylinder pressure. On the other hand, supply of the master cylinder pressure to the wheel cylinders of the required wheels is newly started according to the control state, and integration of the change speed of the master cylinder pressure from the time when the change speed (dPmc) of the master cylinder pressure becomes negative is performed. Value (idPmc)
Has been confirmed by the applicants to show, for example, a transition as shown in the time chart of FIG.

That is, when the supply of the master cylinder pressure to the wheel cylinder of the required wheel is newly started, the change speed of the master cylinder pressure temporarily becomes negative, and then reverses to positive as described above. And returns to the state of value “0”. Correspondingly, the integral values of the changing speeds of the master cylinder pressure become negative numbers until they cancel each other, and thereafter return to the state of the value “0”.

In addition, when the driver operates the brake pedal instead of supplying the master cylinder pressure to the wheel cylinders of the required wheels, the change speed of the master cylinder pressure is temporarily temporary as described above. After reaching the number, the state returns to the value “0”. Correspondingly, the integral value of the change speed of the master cylinder pressure is a positive number.

Further, when the operation state of the brake pedal by the driver is released, the change speed of the master cylinder pressure is relatively small as described above and becomes a negative number indicating redundant fluctuation characteristics. Correspondingly, the integral value of the change speed of the master cylinder pressure is also a negative number which is also relatively small and shows redundant fluctuation characteristics.

Therefore, the operation state and the release state of the brake pedal by the driver can be detected by taking into account each transition (variation characteristic) of the integral value of the change speed of the master cylinder pressure.

According to the first aspect of the present invention, in a state where the master cylinder pressure is automatically controlled, the integrated value of the calculated master cylinder pressure change speed is set to, for example, a predetermined positive number. By exceeding the braking state determination threshold, the operating state of the brake pedal is accurately determined regardless of the stroke amount of the brake pedal. Incidentally, when the supply of the master cylinder pressure to the wheel cylinder of the required wheel is newly started, the integral value of the change speed of the master cylinder pressure is:
They only become negative until they cancel each other out, and therefore are not confused in this determination.

According to the second aspect of the present invention, in the state where the master cylinder pressure is controlled to be automatically increased, the calculated master cylinder pressure change speed is set to, for example, a predetermined positive number. By exceeding the state judgment threshold,
Regardless of the stroke amount of the brake pedal, its operation state is accurately determined. The change in the change speed of the master cylinder pressure when the supply of the master cylinder pressure to the wheel cylinder of the required wheel is newly started is determined by setting the calculated master cylinder pressure change speed to, for example, a predetermined negative number. By performing the above-described operation state determination after a lapse of a braking state determination prohibition time sufficient for ending the fluctuation from the point in time when the value falls below the first braking state determination threshold value, the determination is not confused. .

According to the third aspect of the present invention, the state in which the calculated master cylinder pressure change speed falls below a non-braking state determination threshold value set to, for example, a predetermined negative number,
For example, based on the continuation of the non-braking state determination prohibition time sufficient to exclude the fluctuation when the supply of the master cylinder pressure to the wheel cylinder of the required wheel is newly started, the operating state of the brake pedal is determined. The determination is suitably canceled.

According to the fourth or fifth aspect of the present invention, a state in which the calculated integrated value of the master cylinder pressure change rate is lower than a non-braking state determination threshold value set to a predetermined negative number, for example, For example, based on the continuation of the non-braking state determination prohibition time sufficient to exclude the fluctuation when the supply of the master cylinder pressure to the wheel cylinder of the required wheel is newly started, the operating state of the brake pedal is determined. The determination is suitably canceled.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) A first embodiment of a vehicle brake control device having an automatic pressurizing function according to the present invention will be described below with reference to FIGS.

As shown in FIG. 2, the vehicle brake control device according to the present embodiment comprises a hydraulic pressure generating device 1 for generating a brake hydraulic pressure.
1 and a pressurizing unit 12 for introducing a servo pressure for automatic pressurization to the apparatus. In addition, the present brake control device includes wheel cylinders 13 to mounted on the right front wheel FR, the left front wheel FL, the right rear wheel RR, and the left rear wheel RL of the vehicle.
A hydraulic pressure control device 17 for supplying brake hydraulic pressure to the ECU 16 and an ECU (electronic control unit: see FIG. 1) 18 for controlling a braking force of each wheel are provided.

The hydraulic pressure generator 11 includes a vacuum booster 19 and a master cylinder 20. Regarding the master cylinder 20, the overall configuration is simplified by omitting a seal member and the like. The hydraulic pressure generating device 11 is configured such that the pedaling force of the brake pedal 21 is amplified by the leverage of the link mechanism and transmitted to the operating rod 22, and the rod 22 is pressed. Further, the force for pushing the rod 22 is amplified by the vacuum booster 19 and transmitted to the first piston 23 of the master cylinder 20, so that the piston 23 is pushed. When the first piston 23 is pushed against the urging force of the spring from the original position shown in FIG.
The communication between the reservoir 4 and the reservoir 25 is cut off, and a hydraulic pressure is generated in the first pressure chamber 24. When the second piston 26 is pressed against the urging force of the spring from the original position shown in the drawing by this liquid pressure, the communication between the second pressurizing chamber 27 and the reservoir 25 is cut off, and the second pressurizing chamber 27 A hydraulic pressure is also generated inside.

In this manner, the first piston 2 is driven by the pedaling force amplified by the link mechanism and the vacuum booster 19.
When 3 is pressed, a brake fluid pressure of the pedal input pressure Pmcin corresponding to the pedal depression force is generated in the first pressurizing chamber 24. Also,
The second piston 26 is pushed by the brake fluid pressure, and the same brake fluid pressure is generated in the second pressurizing chamber 27. In the following description, “increased in pressure by the vacuum booster 19” is used to mean that the pedaling force is amplified by the leverage of the link mechanism.

The master cylinder 20 has a third piston for applying hydraulic pressure to the end face of the first piston 23 on the booster side.
The pressure chamber 28 is provided, and the hydraulic pressure generated by the pressure unit 12 is introduced into the third pressure chamber 28. When the first piston 23 is pressed by the hydraulic pressure (three-chamber pressure P3), the three-chamber servo in which the three-chamber pressure P3 is amplified by the pressure receiving area ratio A of the first piston 23 in the first pressurizing chamber 24. Pressure Pmc
A third brake fluid pressure is generated. Here, the pressure receiving area ratio A is equal to the first and second pressure chambers 24 and 27.
And the pressure receiving area ratio of the piston 23 in the third pressurizing chamber 28.

As described above, the component of the pedal input pressure Pmcin corresponding to the pedal depression force amplified by the vacuum booster 19 and the pressure unit 12
, A master cylinder pressure including a component of the three-chamber servo pressure Pmc3 corresponding to the hydraulic pressure introduced is generated.

The pressure unit 12 is a pump 2 for pumping the brake fluid stored in the reservoir 25 into the third pressure chamber 28.
9, a motor 30 for driving the pump 29, and a valve opening at an opening corresponding to the current value of the input signal (control signal).
And a linear valve 31 for releasing the brake fluid discharged from the reservoir 9 to the reservoir 25 side. Therefore, this linear valve 31
The ECU 18 outputs a control signal indicating a current value from the ECU 18 so that the hydraulic pressure (three-chamber pressure P3) proportional to the value (current value) of the control signal is increased by the third pressure due to the hydraulic pressure-current characteristic of the linear valve 31. It is introduced into the pressure chamber 28. The introduced hydraulic pressure is the same as the pressure of the brake fluid discharged from the pump 29 and the linear valve 31.
Is the pressure difference with the pressure drop corresponding to the opening degree of.

The brake fluid pressure generated in the master cylinder 20 is supplied to each of the wheel cylinders 13 to 16 separately in two systems, a front wheel side and a rear wheel side. That is, the master cylinder 20 and the wheel cylinders 13 to 16 of each wheel
The hydraulic pressure control device 17 connecting between the two is a front and rear pipe.

Specifically, the brake fluid pressure generated in the first pressurizing chamber 24 is sent to the main passage 32. This main passage 32
Are connected to the wheel cylinders 13 and 14 via a front circuit section of the hydraulic pressure control device 17, respectively. That is, the main passage 32 is connected to the wheel cylinders 13 and 14 via holding valves 33a and 34a provided in two passages that are divided from the middle of the main passage 32, respectively. A passage connecting the wheel cylinder 13 and the holding valve 33a and a passage connecting the wheel cylinder 14 and the holding valve 34a are connected to the reservoir 38 via pressure reducing valves 33b and 34b, respectively.

On the other hand, the second pressure chamber 2 of the master cylinder 20
The brake fluid pressure generated at 7 is sent to the main passage 37.
The main passage 37 is connected to the wheel cylinders 15 and 16 via a rear circuit of the hydraulic pressure control device 17. That is, the main passage 37 is connected to the wheel cylinders 15 and 16 via the holding valves 35a and 36a provided in two passages that are divided in the middle. Further, a passage connecting the wheel cylinder 15 and the holding valve 35a and the wheel cylinder 16 and the holding valve 36
a are connected to the pressure reducing valves 35b and 36b, respectively.
Is connected to the reservoir 39 via the.

Holding valves 33a, 34a, 35a, 36a
Are normally open solenoid valves, respectively, and the pressure reducing valves 33b, 34
b, 35b, and 36b are normally closed solenoid valves.
These solenoid valves are each excited (turned on) by a hydraulic pressure control signal (control current) output from the ECU 18.

Accordingly, the holding valve 33a and the pressure reducing valve 33b for the right front wheel FR will be described as a representative.
When a is in the non-excited state (OFF) and the pressure reducing valve 33b is also in the non-excited state (OFF), the wheel cylinder 13 is in communication with the master cylinder 20 in a state of being disconnected from the reservoir 38, so that the pressure is in the increased pressure state. In this pressure increasing state, the brake fluid pressure of the wheel cylinder 13 is increased. Also,
When both the holding valve 33a and the pressure reducing valve 33b are excited (when they are turned on), the wheel cylinder 13 communicates with the reservoir 38 while being disconnected from the master cylinder 20, so that the pressure is reduced. In this reduced pressure state, the brake fluid pressure of the wheel cylinder 13 is reduced. And
When the holding valve 33a is excited (ON) and the pressure reducing valve 33b is not excited (OFF), the wheel cylinder 13
Is shut off from both the master cylinder 20 and the reservoir 38, so that the state is maintained. In this holding state, the brake fluid pressure of the wheel cylinder 13 is held without being increased or decreased.

The above three states are switched by turning on and off a hydraulic pressure control signal output from the ECU 18 to the holding valve and the pressure reducing valve of each wheel, so that each wheel cylinder 13
The braking force of each wheel is individually controlled by changing the brake fluid pressure supplied to 〜16.

In the front system circuit section of the hydraulic pressure control device 17, the brake fluid accumulated in the reservoir 38 is pumped by a pump 41 driven by a motor 40, and two check valves provided in a pump passage 42 are provided. And damper 4
3, the air is returned to the passage on the upstream side of the holding valves 33a and 34a. Similarly, also in the rear circuit section of the hydraulic pressure control device 17, the brake fluid accumulated in the reservoir 39 is pumped up by a pump 44 driven by a motor 40, and the two check valves and a damper provided in a pump passage 45 are provided. The air is returned to the passage on the upstream side of the holding valves 35a and 36a through the port 46.

In the front system circuit section, return passages 47, 48 are provided to allow the brake fluid to return to the master cylinder 20 side from the wheel cylinders 13, 14 bypassing the holding valves 33a, 34a. ing.
Each of the return passages 47 and 48 is provided with a check valve 49 or 50 for preventing a backflow of the brake fluid. Similarly, the wheel cylinders 15,
Recirculation passages 51 and 52 are provided to allow the brake fluid to recirculate to the master cylinder 20 side by bypassing the holding valves 35 a and 36 a from the valve 16. Each return passage 51, 5
2 includes check valves 53 and 54 for preventing backflow of brake fluid.
Are provided respectively.

The main passage 32 is provided with a hydraulic pressure sensor 62 as pressure detecting means for detecting the master cylinder pressure Pmc generated in the master cylinder 20. Each of the wheels FR, FL, RR, RL is provided with a wheel speed sensor 63, 64, 65, 66 for detecting the respective wheel speed. The brake pedal 21 is provided with a stop lamp switch (SLS) 67 that is turned on when the pedal 21 is depressed.

Next, the configuration of the ECU 18 will be described with reference to FIG. The ECU 18 is an electronic control unit mainly composed of a microcomputer. Specifically, the ECU 18 includes a CPU (Central Processing Unit)
70, RAM (random access memory) 71, ROM
(Read only memory) 72, an input circuit unit 73, an output circuit unit 74, and the like.

The input circuit 73 includes the hydraulic pressure sensor 6
2. Stop lamp switch 67 and wheel speed sensor 63
To 66 are connected. In addition, the input circuit 73 includes a steering angle sensor 81 for detecting a steering angle, a vehicle acceleration sensor 8 for detecting longitudinal and lateral acceleration occurring in the vehicle.
2 and a yaw rate sensor 83 for detecting a yaw rate generated in the vehicle. Further, the output circuit 74 includes the motor 30 and the linear valve 31 of the pressurizing unit 12,
Holding valves 33a, 34a, 35a, 3 of hydraulic pressure control device 17
6a, the pressure reducing valves 33b, 34b, 35b, 36b, the motor 40 and the like are connected.

The ECU 18 having such a structure detects the pedal depression force or the vehicle state based on the sensors 62 to 67 and 81 to 83. Then, the ECU 18 controls the automatic pressurization of the master cylinder pressure by the pressurizing unit 12 according to the detected pedaling force or the vehicle state, and controls the braking force of each wheel by driving the hydraulic pressure control device 17. .

For example, based on the detection of the vehicle state (vehicle state quantity) during steering such as turning, the ECU 18 controls the braking force of each wheel so as to reduce the deviation from the target line during steering such as during turning. The vehicle stability control for individually controlling the vehicle stability control is executed. Further, the ECU 18 executes an anti-skid control for controlling a braking force applied to each wheel based on detection of a vehicle state (vehicle state quantity) at the time of vehicle braking so as to prevent locking of the wheel at the time of vehicle braking. I do. Further, the ECU 18 performs traction control for applying a braking force to the drive wheels based on the detection of the vehicle state (vehicle state quantity) at the time of driving the vehicle so as to prevent the slip of the drive wheels at the time of driving the vehicle. E for each of these controls
The CU 18 controls the driving of the motor 30 of the pressurizing unit 12 and the current value of the control signal output to the linear valve 31 according to the detected vehicle state and the like. Thereby, the ECU 18
Controls the automatic pressurization of the master cylinder pressure by changing the hydraulic pressure (three chamber pressure P3) introduced by the pressurizing unit 12 into the third pressurizing chamber 28 of the master cylinder 20. With this,
The ECU 18 controls the holding valves 33a, 34a, 35a, 36a, the pressure reducing valves 33b, 34b, 35b, 36b, the motor 40, and the like of the hydraulic pressure control device 17 according to the control mode at that time, and reduces the braking force of each wheel. Control.

Hereinafter, the operation of the vehicle brake control device according to the present embodiment will be described with reference to FIGS. The routine shown in the flowchart of FIG. 3 is started when an ignition switch (not shown) of the vehicle is turned on and the engine is started. In this routine, the ECU 18 makes necessary initial settings, and then first, in step 100, a hydraulic pressure sensor 62, a stop lamp switch 67, wheel speed sensors 63 to 66, a steering angle sensor 81, a vehicle acceleration sensor 8
2 and an input process for reading detection signals output from the yaw rate sensor 83 and the like.

Next, the ECU 18 proceeds to step 101, and the current control mode is changed to the vehicle stability control (hereinafter referred to as "VSS").
C control ”). The determination of the VSC control is executed by, for example, confirming a flag of each control mode set for the vehicle state detected in the input processing. Here, if it is determined that the VSC control is not currently being performed, the ECU 18 returns to step 100 as it is.

On the other hand, when it is determined that the VSC control is being performed, the ECU 18 determines that the automatic pressurization control of the master cylinder pressure is being performed. And the ECU 18
Shifts to step 102, and determines whether or not the master cylinder pressure change speed dPmc was a positive number at the time of the previous calculation. The master cylinder pressure change speed dPmc is calculated based on the difference between the current master cylinder pressure Pmc ′ detected by the hydraulic pressure sensor 62 and the previous master cylinder pressure Pmc each time the calculation is performed.

Here, when it is determined that the master cylinder pressure change speed dPmc was a positive number in the previous calculation, E
The CU 18 proceeds to step 103 to determine whether the current master cylinder pressure change speed dPmc is equal to or less than the value “0”. Then, the current master cylinder pressure change speed dPmc
Is determined to be less than or equal to the value “0”, the ECU 18 determines that the master cylinder pressure change speed dPmc is newly negative this time, and proceeds to step 104. Then, the integral value idPmc of the master cylinder pressure change speed is cleared, and the routine proceeds to step 105. These steps 10
The processing of 2 to 104 is performed in the wheel cylinder 13 of the required wheel.
The supply of the master cylinder pressure to .about.16 is assumed to be newly started.
To start the calculation of.

On the other hand, in step 102, the master cylinder pressure change speed dPmc is not a positive number at the time of the previous calculation.
Alternatively, if it is determined in step 103 that the current master cylinder pressure change speed dPmc is a positive number, the ECU
The process proceeds to step 105 on the assumption that the calculation of the integral value idPmc of the master cylinder pressure change speed has already been started and is continued.

In step 105, the ECU 18 sets the current integrated value idPmc to the previous integrated value idPmc,
The process is updated to a value obtained by adding the calculated master cylinder pressure change speed dPmc, and the routine goes to Step 106.

In step 106, the ECU 18 determines whether or not the vehicle is currently in a braking state. The determination of the braking state is performed by checking a braking state determination flag, which will be described later, which is set each time the calculation is performed. If it is determined that the vehicle is not currently in the braking state, the ECU 18 proceeds to step 107.
Then, it is determined whether or not the integrated value idPmc is larger than a braking state determination threshold value KS2 (see FIG. 4B) set to a predetermined positive number. Then, the above integral value id
When it is determined that Pmc is larger than the braking state determination threshold value KS2, the ECU 18 determines that the vehicle is in the braking state, shifts to step 109, and executes a braking state determination process.
That is, in step 109, the ECU 18
The braking state determination flag shown in (c) is turned on, and the process returns to step 100. When the braking state determination flag is turned on, the driving of the hydraulic pressure control device 17 is controlled so as to apply more braking force to a required wheel, and the result is reflected on the vehicle deceleration.

On the other hand, if it is determined in step 106 that the vehicle is currently in the braking state, the ECU 18 proceeds to step 1.
08, the state in which the integral value idPmc is smaller than the non-braking state determination threshold value KS1 (see FIG. 4B) set to a predetermined negative number continues for a predetermined non-braking state determination prohibition time KT. Judge whether it is. The integral value idPmc when the supply of the master cylinder pressure to the wheel cylinders 13 to 16 of the required wheels is newly started is:
Until they cancel each other, they become negative (Fig. 4
(See (b)), however, the non-braking state determination prohibition time KT is set so that this case is excluded from the release determination.

Here, if it is determined that the state in which the integrated value idPmc is smaller than the non-braking state determination threshold value KS1 does not continue the non-braking state determination prohibition time KT, the ECU performs
In step 18, it is determined that the vehicle is in the braking state, and the process proceeds to step 109 to execute the braking state determination process. That is, in step 109, the ECU 18 continues to turn on the braking state determination flag and returns to step 100. If it is determined in step 108 that the state in which the integrated value idPmc is smaller than the non-braking state determination threshold value KS1 continues for the non-braking state determination prohibition time KT, the ECU 1
No. 8 determines that the vehicle is in the non-braking state, and proceeds to step 110 to execute the non-braking state determination process. That is, in step 110, the ECU 18 turns off the braking state determination flag and returns to step 100.

As described in detail above, according to this embodiment, the following effects can be obtained. (1) In the present embodiment, at the time of VSC control, the above integral value id
When Pmc exceeds the braking state determination threshold value KS2, the operation state of the brake pedal 21 can be accurately determined regardless of the stroke amount. Note that the integral value idPmc when the supply of the master cylinder pressure to the wheel cylinders 13 to 16 of the required wheels is newly started is only a negative number until they cancel each other out. Don't be confused.

(2) In this embodiment, the integral value idP
A state in which mc is lower than the non-braking state determination threshold value KS1 is a state in which non-braking is sufficient to exclude fluctuations when the supply of the master cylinder pressure to the wheel cylinders 13 to 16 of the required wheels is newly started. Based on the continuation of the state determination prohibition time KT, the determination of the operation state of the brake pedal 21 can be appropriately released.

(Second Embodiment) Hereinafter, a second embodiment of a vehicle brake control device having an automatic pressurizing function according to the present invention will be described with reference to the drawings. In the second embodiment, the determination of the operation state of the brake pedal 21 and the release determination are performed only by the master cylinder pressure change speed dPmc. The same parts as those in the first embodiment are described in detail. Description is omitted.

Hereinafter, the operation of the vehicle brake control device according to this embodiment will be described with reference to FIGS. 5 and 6, together with the contents of the processing executed by the ECU 18. The routine shown in the flowchart of FIG. 5 is started when an ignition switch (not shown) of the vehicle is turned on and the engine is started. In this routine, after making the necessary initial settings, the ECU 18 first performs the same input processing as in step 100 of the first embodiment in step 200.

Next, the ECU 18 proceeds to step 201 and determines whether the current control mode is the VSC control as in step 101 of the first embodiment. If it is determined that the VSC control is not currently being performed, the ECU 1
8 returns to step 200 as it is.

On the other hand, if it is determined that the VSC control is currently being performed, the ECU 18 determines that the master cylinder pressure is under automatic pressure control. Then, the ECU 18 proceeds to step 202 and determines whether or not the vehicle is currently in the braking state. The determination of the braking state is performed by checking a braking state determination flag, which will be described later, which is set each time the calculation is performed. Here, if it is determined that the vehicle is not currently in the braking state,
The ECU 18 proceeds to step 203 and determines whether the master cylinder pressure change speed dPmc is lower than a first braking state determination threshold value KS0 that is a predetermined negative number.

Here, the master cylinder pressure change speed dPmc
Is determined to be below the first braking state determination threshold value KS0, the ECU 18 proceeds to step 205 and determines that the master cylinder pressure change speed dPmc is not below the first braking state determination threshold value KS0. Step 2
Move to 04. Then, in step 204, EC
U18 executes a count process of the braking state determination prohibition timer ks2tm. Specifically, as shown in FIG. 6A, the calculated master cylinder pressure change speed dP
When mc falls below the first braking state determination threshold value KS0,
The braking state determination prohibition timer ks2 which is the elapsed time thereafter.
Count tm. Thereafter, the process proceeds to step 206.

In step 205, the ECU 18 determines the state of the wheel cylinders 13 to 16 at that time (for example, whether the wheel cylinder in the holding state is one wheel,
A different predetermined braking state determination prohibition time KT2 is set depending on whether the vehicle is a wheel or not. As described above, when the supply of the master cylinder pressure to the wheel cylinders 13 to 16 of the required wheels is newly started, the master cylinder pressure change speed dPmc temporarily becomes a negative number, and then reverses to a positive number. And the value "0"
(See FIG. 6A), but the time required to return to the state of the value “0” depends on the number of wheel cylinders in the holding state. The braking state determination inhibition time KT2 is a determination inhibition time for preventing such a change from being erroneously determined as the operation state of the brake pedal 21.

E where the braking state determination inhibition time KT2 is set
The CU 18 thereafter proceeds to step 212. on the other hand,
In step 206, the ECU 18 determines that the braking state determination inhibition timer ks2tm has reached the braking state determination inhibition time KT.
It is determined whether it is greater than 2 and if it is, it is determined that the time for avoiding the erroneous determination has elapsed, and the process proceeds to step 207.

In step 207, the ECU 18 determines whether or not the calculated master cylinder pressure change speed dPmc is larger than a predetermined positive braking state determination threshold value KS2 (see FIG. 6A). If it is larger, it is determined that the vehicle is in the braking state, and the routine proceeds to step 211, where a braking state determination process is executed. That is, step 211
The ECU 18 turns on the braking state determination flag shown in FIG. 6B and returns to step 200. When the braking state determination flag is turned on, the driving of the hydraulic pressure control device 17 is controlled so as to apply more braking force to a required wheel, and the result is reflected on the vehicle deceleration.

In step 206, the braking state determination inhibition timer ks2tm sets the braking state determination inhibition time K
If it is determined that T2 is equal to or less than T2, or if it is determined in step 207 that the master cylinder pressure change speed dPmc is equal to or less than the braking state determination threshold value KS2, the ECU 18 determines that the vehicle is in the non-braking state, and proceeds to step 212. The braking state determination process is executed. That is, in step 212, the ECU 18 turns off the braking state determination flag and returns to step 200.

On the other hand, if it is determined in step 202 that the vehicle is in the braking state, the ECU 18 proceeds to step 208 and the non-braking state determination threshold KS1 (FIG. 6) in which the master cylinder pressure change speed dPmc is a predetermined negative number. (Refer to (a)). When it is determined that the master cylinder pressure change speed dPmc is equal to or greater than the non-braking state determination threshold value KS1, the ECU 18 determines that the vehicle is in the braking state, shifts to step 211, and executes a braking state determination process. That is, in step 211, the ECU 18 continues to turn on the braking state determination flag and returns to step 200.

In step 208, the master cylinder pressure change speed dPmc is set to the non-braking state determination threshold value K.
If it is determined that it is less than S1, the ECU 18 proceeds to step 209 to execute a count process of the braking state release timer ks1tm. Specifically, as shown in FIG. 6A, when the master cylinder pressure change speed dPmc falls below the non-braking state determination threshold KS1, the braking state release timer ks1tm, which is the elapsed time thereafter, is set. Count.

Then, the ECU 18 proceeds to step 210 to determine whether or not the braking state release timer ks1tm is longer than a predetermined non-braking state determination inhibition time KT1 (see FIG. 6A). The master cylinder pressure change speed dP when the supply of the master cylinder pressure to the wheel cylinders 13 to 16 of the required wheels is newly started.
mc is temporarily negative, then inverted to a positive number,
The state returns to the value “0”. The non-braking state determination inhibition time K
T1 is a determination prohibition time for preventing such a change from being erroneously determined as the operation release state of the brake pedal 21. Here, if it is determined that the braking state release timer ks1tm is equal to or less than the non-braking state determination inhibition time KT1, the ECU 18
Determines that the vehicle is in the braking state, and proceeds to step 211 to execute a braking state determination process. That is, in step 211, the ECU 18 continues to turn on the braking state determination flag and returns to step 200.

Further, the braking state release timer ks1tm
Is longer than the non-braking state determination prohibition time KT1, the ECU 18 determines that the vehicle is in the non-braking state, shifts to step 212, and executes the non-braking state determination process. That is, in step 212, the ECU 18
The braking state determination flag is turned off, and the process returns to step 200.

As described in detail above, according to the present embodiment, the following effects can be obtained. (1) In the present embodiment, at the time of VSC control, the master cylinder pressure change speed dPmc is equal to the second braking state determination threshold value KS.
By exceeding 2, the operation state of the brake pedal 21 can be accurately determined regardless of the stroke amount. The change in the master cylinder pressure change speed dPmc when the supply of the master cylinder pressure to the wheel cylinders 13 to 16 of the required wheels is newly started depends on whether the master cylinder pressure change speed dPmc is the first braking state determination. By performing the above-described operation state determination after the braking state determination prohibition time KT2 sufficient to end the fluctuation from the point in time when the value falls below the threshold value KS0 is not confused in the determination.

(2) In this embodiment, the state in which the master cylinder pressure change speed dPmc falls below the non-braking state determination threshold value KS1 is determined by the wheel cylinders 13 to 16 of the required wheels.
The determination of the operation state of the brake pedal 21 is appropriately canceled based on the continuation of the non-braking state determination prohibition time KT1 sufficient to exclude the fluctuation when the supply of the master cylinder pressure to the engine is newly started. can do.

The embodiment of the present invention is not limited to the above embodiment, but may be modified as follows. The method for determining the release of the braking state in the first embodiment may be applied to the determination for releasing the braking state in the second embodiment. Conversely, the method for determining the release of the braking state in the second embodiment is the first method. The present invention may be applied to the release determination of the braking state of the embodiment. Even with such a change, an effect similar to the effect (2) of the above embodiments can be obtained.

In the above embodiments, the present invention is applied to the VSC control. However, if the master cylinder pressure is under the automatic pressurization control, other control states such as traction control may be used. Is also good.

The structure for automatically pressurizing the master cylinder pressure (pressurizing unit 12) in each of the above embodiments is merely an example, and other structures may be employed. In each of the above embodiments, the vacuum booster 19
Although the hydraulic pressure generating device 11 having the above is adopted, a hydraulic pressure generating device in which the vacuum booster 19 is omitted may be used.

In each of the above embodiments, the master cylinder 2
Although the hydraulic pressure control device 17 connecting between 0 and the wheel cylinders 13 to 16 of each wheel is a front and rear pipe, the hydraulic pressure control device 17 may be a so-called X pipe.

In each of the above embodiments, a master cylinder having one piston may be used instead of the tandem type master cylinder 20. -In the above embodiment,
Although the configuration that can execute the anti-skid control and the traction control is adopted, these controls may be omitted.

[0075]

As described in detail above, according to the first or second aspect of the present invention, an automatic pressurizing function of the master cylinder pressure capable of accurately determining the operation state of the brake pedal by the driver is provided. Vehicle braking control device having the same.

According to the third aspect of the invention, the determination of the operation state of the brake pedal can be appropriately released.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a schematic configuration of a first embodiment according to the present invention.

FIG. 2 is a schematic configuration diagram showing the whole of the embodiment;

FIG. 3 is a flowchart showing the operation of the embodiment.

FIG. 4 is a time chart showing the operation of the embodiment.

FIG. 5 is a flowchart showing the operation of the second embodiment according to the present invention.

FIG. 6 is a time chart showing the operation of the embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Hydraulic pressure generator 12 Pressurizing unit 13-16 Wheel cylinder 17 Hydraulic pressure controller 18 ECU 20 Master cylinder 62 Hydraulic sensor as pressure detecting means

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Hiroshi Nita 2-1-1 Asahi-cho, Kariya-shi, Aichi, Japan F-term (reference) 3D046 BB21 BB28 BB29 CC02 EE01 HH02 HH16 KK07 KK08 LL05 LL09 LL11 LL23 LL43 3D048 BB35 CC08 CC54 HH13 HH26 HH38 HH50 HH53 HH66 HH68 HH75 HH77 RR06 RR35

Claims (5)

[Claims] An automatic pressurizing control means for automatically pressurizing a master cylinder pressure, and controlling the supply of the automatically controlled master cylinder pressure to a wheel cylinder of each wheel to control a braking force of the wheel. A vehicle braking control device comprising: a braking force control unit; a pressure detection unit that detects the master cylinder pressure; and a master cylinder pressure change speed that calculates a change speed of the master cylinder pressure based on the detected master cylinder pressure. Calculating means, while the automatic pressurizing means is performing automatic pressurizing control of the master cylinder pressure, an integrated value of the master cylinder pressure changing rate from the time when the calculated master cylinder pressure changing rate becomes negative. A change speed integral value calculating means for calculating a master cylinder pressure change speed calculated when the integrated value exceeds a braking state determination threshold value. Vehicle brake control apparatus characterized by comprising a pedal operation determining means determines that the operation state of the brake pedal. 2. An automatic pressurizing control means for automatically pressurizing and controlling the master cylinder pressure, and controlling the supply of the master cylinder pressure under the automatic pressurizing control to the wheel cylinder of each wheel to control the braking force of the wheel. A vehicle braking control device comprising: a braking force control unit; a pressure detection unit that detects the master cylinder pressure; and a master cylinder pressure change speed that calculates a change speed of the master cylinder pressure based on the detected master cylinder pressure. Calculating means for determining a braking state from a point in time when the calculated master cylinder pressure change speed falls below a first braking state determination threshold value in a state in which the automatic pressurizing means controls the master cylinder pressure automatically. After the prohibition time has elapsed, when the master cylinder pressure change speed exceeds the second braking state determination threshold value, the pedal operation is determined to be the operation state of the brake pedal. A vehicle braking control device comprising: a work determination unit. 3. The braking control device for a vehicle according to claim 1, wherein the calculated master cylinder pressure change speed is in a state in which the automatic pressurizing unit controls the master cylinder pressure automatically. When the state below the non-braking state determination threshold value continues for a non-braking state determination prohibition time, a pedal operation determination releasing unit that releases the determination of the operation state of the brake pedal by the pedal operation determining unit is provided. Vehicle braking control device. 4. The braking control device for a vehicle according to claim 1, wherein the state in which the calculated integrated value of the master cylinder pressure change speed is lower than the non-braking state determination threshold has continued for the non-braking state determination prohibition time. A brake control device for a vehicle, comprising: pedal operation determination canceling means for canceling the determination of the operation state of the brake pedal by the pedal operation determining means. 5. The braking control device for a vehicle according to claim 2, wherein the calculated master cylinder pressure change speed is negative in a state where the automatic pressurizing unit is performing automatic pressurizing control of the master cylinder pressure. A change speed integral value calculating means for calculating an integral value of the master cylinder pressure change speed from the time point at which the master cylinder pressure change speed has reached a non-braking state determination threshold. A brake control device for a vehicle, comprising: pedal operation determination canceling means for canceling the determination of the operation state of the brake pedal by the pedal operation determining means when the braking state determination prohibition time continues.