JPH0717390A - Brake controller - Google Patents

Abstract

PURPOSE:To obtain optimum brake characteristics according to the tendency related to the stepping operation for a brake pedal and the reaction speed for avoiding danger, by installing a control means for controlling an assisting force varying means on the basis of the assistance quantity determined by an assistance quantity determining means. CONSTITUTION:A control unit 20 detects the deceleration pattern in brake application on the basis of the signal supplied from a vehicle speed sensor 42, and learns brake stepping force on the basis of the deceleration pattern, and determines the boost factor (assistance quantity) of a subbooster 4 on the basis of the result of the learning. The target pressure value in an air chamber 14 for obtaining the boost factor is set, and the duty ratio of the control signal outputted into the control valves 16 and 17 is calculated from the target pressure value, and the control valves 16 and 17 are duty-controlled so that the pressure value in the air chamber 14 becomes close to the target pressure value. Further, in the control, the feedback control utilizing the output of a pressure sensor 43 is performed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brake control device for a vehicle.

[0002]

2. Description of the Related Art A general automobile is provided with assisting means such as a booster (booster) in order to assist the braking force generated by the depression operation of a brake pedal.

And, for example, Japanese Patent Laid-Open No. 61-10236.
In the vehicle braking device disclosed in Japanese Patent Publication No. 1, the braking force generated corresponding to the depression amount of the brake pedal is changed by changing the assist force based on the load applied to the wheels.

[0004]

However, when the driver performs a pedal operation on the brake padal, the mode of the pedal operation on the brake padal varies depending on the driver's habit or the individual difference in the reaction speed for avoiding the danger. With respect to the stepping operation of the driver, a driver having a peculiar habit and a driver having a slow reaction speed of danger avoidance may not be able to perform an appropriate brake operation.

Therefore, even if the amount of depression of the brake pedal is the same, the magnitude of the generated braking force varies depending on the running state of the vehicle and the driver's habit regarding the depression operation of the brake padal and the reaction speed for avoiding danger. Is preferably changed to.

In view of the above circumstances, it is an object of the present invention to provide a brake control device capable of obtaining an optimum brake characteristic in accordance with a driver's habit of depressing a brake padal and a reaction speed for avoiding a danger. To do.

[0007]

As shown in FIG. 1, a brake control device according to a first aspect of the present invention includes an assist means for assisting a braking force generated by a driver's operation of depressing a brake pedal, and an assist means. From the assist force varying means capable of changing the generated assist force, the first detecting means for detecting the vehicle speed, the second detecting means for detecting the distance between the own vehicle and the obstacle, and the accelerator pedal during braking. Pedal stepping time measuring means for measuring the stepping time to the brake pedal, vehicle speed and obstacle distance detected by the first and second detecting means during braking, and pedal measured by the measuring means Based on the driving characteristic learning means for learning the driving characteristic of the driver based on the stepping time, and the driving characteristic learned by the learning means. And an assist amount determination means for determining a cyst volume and is characterized by comprising a control means for controlling the assisting force variation means based on the assist amount determined by said assist amount determination means.

The learning of the driving characteristics of the driver by the learning means is based on the ratio of the standard pedal depression time preset from the vehicle speed and the obstacle distance to the pedal depression time measured by the measuring means. Is done.

Further, by learning the driving characteristics of the driver, the habit regarding the depression operation of the brake pedal of the driver is judged.

Furthermore, the reaction speed for avoiding danger of the driver is determined by learning the driving characteristics of the driver.

The habit of the driver is judged on the basis of a map showing the relationship between the vehicle speed and the obstacle distance.

In this case, the assisting force is increased for the driver who has the habit of shortening the inter-vehicle distance.

The assisting force is increased for a driver who has a slow reaction speed for avoiding a hazard with respect to an obstacle.

A control device for a brake according to the second invention is
It is characterized in that a brake pedal effort learning means for learning the brake pedal effort is provided, and the assist amount is determined based on the learning of the brake pedal effort by the learning means.

One embodiment of the brake control device according to the second aspect of the present invention is, as shown in FIG. 11, an assisting means for assisting a braking force generated by a driver's operation of depressing a brake pedal, and the assisting means. Assist force varying means capable of changing the generated assist force, deceleration pattern detecting means for detecting a deceleration pattern of the vehicle body during brake operation, and brake pedal force learning for learning brake pedal depressing force based on detection of the deceleration pattern by the detecting means Means, an assist amount determining means for determining an assist amount based on the learning of the brake pedal force by the learning means, and a control means for controlling the assist force varying means based on the assist amount determined by the assist amount determining means. It is characterized by

As shown in FIG. 21, another embodiment of the brake control device according to the second aspect of the present invention is, as shown in FIG. 21, an assist means for assisting a braking force generated by a driver's operation of depressing a brake pedal, and the assist means. An assist force varying means capable of changing the generated assist force,
Obstacle distance detecting means for detecting the distance between the host vehicle and the obstacle, pedal change time measuring means for measuring the change time from the accelerator pedal to the brake pedal during braking, and the obstacle distance detecting means. Brake pedal effort learning means for learning the brake pedal effort based on the obstacle distance detected by the pedal depression time and the pedal depression time measured by the pedal depression time measuring means, and an assist amount based on the learning of the brake depression force by the learning means. Is provided, and a control means for controlling the assist force varying means based on the assist amount determined by the assist amount determining means.

In this case, when the obstacle distance detected by the obstacle distance detecting means and the pedal depression time measured by the pedal depression time measuring means are relatively short, the learning of the brake pedal depression force is performed. Is done.

A control device for a brake according to the third invention is
A plurality of assisting means for assisting the braking force generated by the driver's operation of depressing the brake pedal are tandemly connected and interposed between the brake pedal and the master cylinder, and at least one of the plurality of assisting means is provided. The assisting force generated from the assisting means
It is characterized in that it is changed by controlling the negative pressure and the atmospheric pressure applied to the at least one assist means.

[0019]

According to the first aspect of the present invention, the driving characteristics of the driver are learned based on the vehicle speed during braking, the obstacle distance (for example, the inter-vehicle distance), and the pedal change time, and the learning is performed. Since the assisting force by the assisting means is determined on the basis of the assisting means, there is an effect that a reliable braking force can always be obtained regardless of the driver's habit of depressing the brake pedal and the slow reaction speed for avoiding danger.

According to the second aspect of the invention, the braking force of the driver is learned based on the deceleration pattern during braking, or based on the obstacle distance and the pedal change time, and the assist means is learned based on the learning. Since the assist force is determined by, there is an effect that a reliable braking force can always be obtained regardless of individual differences in the driver's brake pedal force.

Further, according to the third invention, a plurality of assisting means for assisting the braking force are connected in a tandem type and are interposed between the brake pedal and the master cylinder. Since the assisting force generated from the at least one assisting device is configured to be changed by controlling the negative pressure and the atmospheric pressure applied to the at least one assisting device, the assisting force can be easily controlled. Therefore, a large assist force can be obtained.

[0022]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 2 is an overall system diagram showing an embodiment of a brake control device according to the first invention shown in the block diagram of FIG.

In FIG. 2, 1 is a brake pedal, 2 is a master cylinder, and between the brake pedal 1 and the master cylinder 2, a main booster 3 and a sub-booster 4 connected in a tandem type are interposed as assisting means. Has been done.

The main booster 3 is provided with a diaphragm 7 provided in the shell 6 in a state of being urged to the left side in the figure by a return spring 5, and a diaphragm chamber 8 partitioned by the diaphragm 7 is provided in the diaphragm chamber 8. The vacuum pressure in the intake manifold of the engine or the vacuum pressure from the vacuum pump is supplied through the check valve 9.

Similarly, the sub-booster 4 is provided with a diaphragm 12 provided in the shell 11 in a state of being urged to the left by the return spring 10 in the drawing. The diaphragm 12 is partitioned by the diaphragm 12. An air chamber 14 is connected to the chamber 13.

A vacuum pressure is supplied to the air chamber 14 through a check valve 15 and a control valve (vacuum valve) 16, and atmospheric pressure is supplied through a control valve 17 (atmospheric pressure valve). It has become. The control valves 16 and 17 are duty solenoid valves.
The opening degree of 7 is duty-controlled by a control unit 20 composed of a microcomputer, whereby the assisting force by the sub-booster 4 is changed as described later.

The brake pedal 1 and the piston 21 of the master cylinder 2 are connected by a rod 22 extending through the central portions of the diaphragms 7 and 12 of the main booster 3 and the sub-booster 4, and this rod 22 is also connected. The central portions of the diaphragms 7 and 12 are engaged with.

Therefore, when the diaphragm chambers 8 and 13 have a negative pressure, the central portions of the diaphragms 7 and 12 are displaced to the right in FIG. 2 against the urging forces of the return springs 7 and 10, respectively, whereby the brakes are braked. An assisting force with respect to the pedaling force of the pedal 1 is applied to the rod 22. Then, in this case, the pedaling force of the brake pedal 1 is applied to the piston 21 of the master cylinder 2 and the assisting force of the sub booster 4 is applied in a manner in which the assisting force of the main booster 3 and the assisting force of the sub booster 4 are combined. It is configured such that the variable assist force changes the entire assist force.

25 is a hydraulic disc brake device,
The disk 27 that rotates with the wheels 26 and the caliper 2
8 and. The caliper 28 is a brake pad 29.
And the cylinder 30 is provided, and the brake pad 29 is pressed against the disc 27 by a force according to the magnitude of the brake fluid pressure supplied from the master cylinder 2 to the cylinder 30 through the oil passage 31. Braking force is generated.

The disc brake device 25 shown in the figure is for the front wheels, and the brake fluid pressure for the brake device for the rear wheels (not shown) is supplied from the oil passage 31 via the proportioning valve 32.

The control unit 20 includes a brake switch signal Bsw from a brake switch 41 which is turned on when the brake pedal 1 is depressed, a vehicle speed sensor 42 for detecting a vehicle speed V, and a pressure in the air chamber 14. ON when the chamber pressure signal from the pressure sensor 43 that detects Pc and the accelerator pedal 44 are depressed
The accelerator switch signal Asw from the accelerator switch 45 and the inter-vehicle distance sensor 47 that detects the inter-vehicle distance L that detects the inter-vehicle distance between the preceding vehicle and the host vehicle are input, and the control unit 20 performs the above control. A control signal is output to the valves 16 and 17.

The control unit 20 learns the driving characteristics of the driver based on the signals from the switches 41 and 45 and the sensors 42 and 47, and based on the learning, the boost ratio (the assist amount) in the sub booster 4. Is set, a target pressure value in the air chamber 14 for obtaining this boosting ratio is set, and the duty ratio of the control signal output to the control valves 16 and 17 is calculated from this target pressure value, and the air chamber 14 is calculated. The control valves 16 (vacuum valves) and 17 (atmospheric pressure valves) are duty-controlled so that the internal pressure value approaches the target pressure value. At the time of this control, feedback control using the output of the pressure sensor 43 is performed.

Next, the content of the control routine executed by the control unit 20 will be described with reference to the flowcharts of FIG. In the following description, S indicates a step.

FIG. 3 shows the general flow. First, in S1, the entire system is initialized, then in S2, the output signals from the above-mentioned switches or sensors are read as input data, and then the operating characteristics in S3. Learning, determining boost ratio in S4 and S5
And output the control signal at. The learning of the driving characteristics is not executed until the data for 10 times is collected after the start,
Until then, the previous learning value is used.

The contents of the system initialization in S1 are shown in FIG. 4. First, the memory values of the first and second variables DK ₁ and DK ₂ representing the driving characteristics of the driver are read, and each variable is set. Reset. The above memory values are saved in the memory when the power is turned off. Resetting variables inter-vehicle distance L ₀ when the accelerator off (Asw = 0), the inter-vehicle distance L ₁ when the brake is on (BSW = 1), the vehicle speed V ₀ which when the accelerator off (Asw = 0), the brake from the accelerator-off Pedal change time to turn on Δ
T, 10 operating characteristic variables DK ₁ (1) to DK, respectively
₁ (10), a DK ₂ (1) to Dk ₂ average calculation data and sample number n of (10) (n = 1 to 10).

4 and 5 show the contents of the data input routine at S2 of FIG. That is, in S11, the accelerator switch signal Asw and the brake switch signal Bs
w and the chamber pressure Pc are read, and the count value of the pedal depression time ΔT is reset in S12 of FIG.

Next, in S13, an accelerator operation determination is made,
Until it is determined that the accelerator is off (Asw = 0) in (S
13, NO), the process returns to S12, and the accelerator is turned off (Asw =
When it is determined to be 0) (S13, YES), the inter-vehicle distance L ₀ and the vehicle speed V ₀ when the accelerator is off are read and the counting of the pedal depression time ΔT is started in S14. Next, the brake operation is determined in S15, and until the brake is turned on (Bsw = 1) (S15, NO), S
Accelerator operation determination is made at 16, and accelerator off (Asw
While it is (= 0) (S16, YES), the brake operation determination is repeated in S15. And brake on (Bsw
= 1) (S15, YES), the process proceeds to S17, the inter-vehicle distance L ₁ is read, and the pedal depression time ΔT
Stop counting and count the number of samples.

6 and 7 show S3 and S4 of FIG.
One mode of each of the routine for learning the driving characteristic and the routine for determining the boost ratio in FIG. In this case, the first driving characteristic variable DK ₁ representing the driving characteristic of the driver is represented by the ratio of the inter-vehicle distance L ₀ to the vehicle speed V ₀ when the accelerator is off (Asw = 0), and the second driving characteristic variable DK ₂ is
It is represented by the product of the inter-vehicle distance L ₁ when the brake is on (Bsw = 1) and the pedal depression time ΔT.

That is, first, in S21 of FIG. 6, DK
₁ (n) = L ₀ / V ₀ , DK ₂ = L ₁ · ΔT, and
In next step S22, the number of samples n is checked. Number of samples n = 1
During 9 to 9 (S22, NO), learning of the driving characteristic is not executed and the previous learning value is used.

When the sample number n reaches 10 (S2
2, YES), 10 driving characteristic variables D each in S23
The average value of K ₁ and DK ₂ is calculated, and the driving characteristic of the driver is learned from this. Then, in the next S24, sorting for the next learning is performed.

FIG. 7 shows the contents of the boost magnification determination routine in S4 of FIG. The control unit 20
As shown in S25 of FIG. 7, a map for calculating the target boost ratio TGK from the learning values of the driving characteristic variables DK ₁ and DK ₂ obtained in S23 of FIG. 6 is stored in the memory of Target boost ratio TGK using map
Is required. The learning values of the driving characteristic variables DK ₁ and DK ₂ reflect the habits and individual differences of the driver. For a driver who tends to shorten the inter-vehicle distance L despite the high vehicle speed V, driving By reducing the characteristic variable DK ₁ , the target boost ratio TGK increases and the assist force is increased. Further, for a driver whose reaction to an obstacle is slow and the pedal change time ΔT tends to be long, the target boost ratio TGK is increased and the assist force is increased by increasing the driving characteristic variable DK _2. .

8 and 9 show S3 and S4 of FIG.
7 shows another aspect of each of the driving characteristic learning routine and the boost magnification determination routine in FIG. In this case, the first driving characteristic variable DK ₁ representing the driving characteristic of the driver is in a state where the inter-vehicle distance L ₀ is short with respect to the vehicle speed V ₀ at the time of accelerator off (Asw = 0) in an emergency, that is, in an emergency. represented by the ratio of the inter-vehicle distance L ₀ with respect to the vehicle speed V _0, the second operating characteristic variables DK ₂ is a standard pedal depression replacement time T
It is expressed as the ratio of pedal change time ΔT to _ST .

That is, first, in S31 of FIG. 8, DK ₁
Calculate (n) = L ₀ / V ₀ , DK ₂ = ΔT / T _ST .
The standard pedal depression time T _ST is calculated from the previous vehicle speed V ₀ / inter-vehicle distance L ₀ map as shown in the figure. Then, in the next S32, the number of samples n is checked. During the number of samples n = 1 to 9 (S32, NO), the learning of the driving characteristic is not executed and the previous learning value is used.

When the sample number n reaches 10 (S3
2, YES), and in S33, it is determined whether or not the current traveling state is in the emergency region where the vehicle speed V ₀ is high and the inter-vehicle distance L ₀ is short, as shown in the figure, and if it is not the emergency region (S33,
NO), 1 is subtracted from the sample number n in S34, and the data at this time is not integrated.

On the other hand, if it is an emergency area (S33, YE
S) and S35, and 10 operating characteristic variables DK ₁ ,
The average value of DK ₂ is obtained, and the driving characteristics of the driver are learned from this. Then, in the next S36, sorting for the next learning is performed.

FIG. 9 shows the contents of the boost magnification determination routine in this case. In the memory of the control unit 20, as shown in S37 of FIG. 9, S3 of FIG.
A map for calculating the target boost ratio TGK from the learned value of the driving characteristic variable DK ₂ obtained in 5 is stored, and the target boost ratio TGK is obtained using this map. In this case, when the pedal depression time ΔT is longer than the standard pedal depression time T _ST even in the emergency region, the driving characteristic variable DK ₂ increases and the target boost ratio TGK increases. Assist power is increased.

Finally, the contents of the output processing in S5 of FIG. 3 will be described based on the flowchart of FIG.

First, in S41, the target chamber pressure TGP corresponding to the target magnification TGK is read from the map showing the relationship between the target magnification TGK and the target chamber pressure TGP.

Next, at S42, the actual chamber pressure Pc is subtracted from the target chamber pressure TGP to obtain the difference ΔP. Then, a dead zone having threshold values of positive and negative predetermined values α and −α is set, and ΔP> α, ΔP <−α, or −α <ΔP <α is set in S43 and S44. Is determined.

First, when it is determined in S43 that ΔP> α (S43, YES), the negative pressure in the vacuum chamber 14 is too high. Therefore, in S45, the control valve 1
6 (vacuum valve) is closed and a decision is made to introduce only atmospheric pressure into the chamber 14. Then, in S46, ΔP of the control signal to the control valve 17 (atmospheric pressure valve)
The duty ratio according to the is read from the map, and S47
Then, while outputting the control signal having this duty ratio to the control valve 17 (atmospheric pressure valve),
A control signal for closing the control valve 16 (vacuum valve), that is, a control signal for setting the duty ratio to 0% is output.

On the other hand, when it is determined in S43 and S44 that ΔP <-α (S43, NO, S44, YE
S) Since the negative pressure in the vacuum chamber 14 is too low, the control valve 17 (atmospheric pressure valve) is closed in S48, and a decision is made to introduce only the vacuum pressure into the chamber 14. Then, in S49, the duty ratio according to ΔP of the control signal for the control valve 16 (vacuum valve) is read from the map, and in S47, the control signal having this duty ratio is output to the control valve 16 (vacuum valve). At the same time, a control signal for setting the duty ratio to 0% is output to the control valve 17 (atmospheric pressure valve).

Further, in S43 and S44, -α <ΔP <α
If it is determined that (S43, NO, S44, N
O), which means that the pressure Pc in the vacuum chamber 14 is within the target range, it is decided to close both the control valves 16 and 17 in S50 and S51, and S47.
Then, a control signal for setting the duty ratio to 0% is output to the control valves 16 and 17, and both control valves 16 and 17 are closed to maintain the pressure in the chamber 14.

The configuration and operation of the first embodiment of the present invention has been described above. According to the present embodiment, the driving characteristics of the driver are learned based on the vehicle speed, the inter-vehicle distance, and the pedal change time. However, since the assisting force by the sub-booster 4 is changed based on the learning result, a reliable and appropriate braking force can be obtained irrespective of the driver's habit of operating the brake pedal and the slow reaction speed for avoiding danger. Can be obtained.

FIG. 12 is an overall system diagram showing a brake control device according to one embodiment of the second invention shown in the block diagram of FIG.

12 has the same structure as that of FIG. 2 except that the accelerator switch 45 and the inter-vehicle distance sensor 47 are omitted from the structure of FIG. Although omitted, the control unit 20 receives a vehicle speed signal from the vehicle speed sensor 42, a brake switch signal from the brake switch 41, and a chamber pressure signal from a pressure sensor 43 that detects the pressure in the air chamber 14. At the same time, the control unit 20 outputs a control signal to the control valves 16 and 17.

The control unit 20 detects a deceleration pattern during braking based on the signal from the vehicle speed sensor 42, learns the brake pedal force based on the deceleration pattern, and boosts the sub booster 4 based on the learning result. The ratio (assist amount) is determined, the target pressure value in the air chamber 14 for obtaining this boost ratio is set, and the duty ratio of the control signal output to the control valves 16 and 17 is calculated from this target pressure value. Then, the control valves 16 (vacuum valves) and 17 (atmospheric pressure valves) are duty-controlled so that the pressure value in the air chamber 14 approaches the target pressure value. Further, during this control, feedback control using the output of the pressure sensor 43 is performed.

Next, the contents of the control routine executed by the control unit 20 will be described with reference to the flowcharts shown in FIG.

First, in S61 of FIG. 13, various memories and constants are initialized, and in S62, the vehicle speed V, the brake switch signal Bsw and the chamber pressure Pc are read. Next, in S63, the vehicle body deceleration G during braking is calculated, and in S64,
If the vehicle speed V at the start of brake operation is 100%, the vehicle speed V
The data of the deceleration G is taken until is 0%.
Then, the vehicle speed position G _MAX % at which the maximum value G _MAX of the deceleration G occurs during one deceleration is calculated in S65. In this case, the curve shown by the solid line in FIG. 13 is G _MAX % = 40.
%, And the curve indicated by the broken line is G _MAX % <40%
And the curve indicated by the one-dot chain line is G _MAX %> 40
%. This G _MAX % value makes it possible to detect when the driver strongly depresses the brake pedal.

In the next S66, the G _MAX % value G of the past five times is set.
While updating M _{1 to} GM ₅ , the average value GP of the G _MAX % values of the past 5 times is calculated in S67. In this way, the driver's brake pedal force is learned by calculating the average value GP. Then, in S68, GP = 40
% Is good, GP> 40% and GP <40% is bad.

In the memory of the control unit 20, as shown in S69 of FIG.
A map for obtaining the boost ratio K from the average value GP of the _MAX % values and the vehicle speed is stored, and the boost ratio K is read from this map. As is clear from the above map, when GP = 40%, the value of the boost ratio K is kept at a constant value of 1.5 from the start of brake operation until the vehicle stops, but when GP> 40%, the boost ratio K is boosted. The value of the magnification K is 1.0 to 2.0 as the vehicle speed decreases.
Increase, and when GP <40%, boost ratio K
Value decreases from 2.0 to 1.0 as the vehicle speed decreases, which corrects individual differences in the driver's brake pedal force and habit when pedaling the brake pedal 1 to a standard value. Become.

Next, in S70, the brake switch signal B
Whether or not sw is 1, that is, brake pedal 1
If Bsw = 0 (S70, NO), the map value K of S69 is set as the target magnification TGK and the boost magnification determination routine is ended, but when Bsw = 1, (S70, YES), the map value is not changed this time so that the driver does not feel uncomfortable.

Finally, based on the target magnification TGK,
The routine for outputting the control signal to the control valves 16 and 17 is executed according to the flowchart of FIG. 15. In the flowchart of FIG. 15, the content of the map of S41 ′ for calculating the target chamber pressure TGP from the target magnification TGK is shown in FIG. Except that it is slightly different from the one used in S41,
Since it is the same as that in FIG. 10, redundant description will be omitted.

As is apparent from the above description, according to the present embodiment, the brake pedal force is indirectly learned by learning the driving characteristics of the driver based on the deceleration pattern of the vehicle body during braking, and based on the learning result, Since the assist force by the sub-booster 4 is changed, it is possible to obtain a reliable braking force by correcting the strength and weakness of the brake pedal force due to individual differences of the driver and the habit of the driver that appears in the way of stepping.

The flow charts of FIGS. 16 to 20 are shown in FIG.
6 shows another embodiment in which the device shown in FIG. 1 learns the brake pedal force from the deceleration pattern of the vehicle body during braking and changes the assist force by the sub-booster 4 based on the learning result.

First, in S81 of FIG. 16, the system is initialized. That is, while reading the memory value of the variable DK that represents the driving characteristics of the driver,
Reset each variable. The above memory values are saved in the memory when the power is turned off. The variable to be reset is the vehicle speed V
(ΔTb) and the brake operation time ΔTb.

16 and 17 show the contents of the data input routine. That is, the brake switch signal Bsw and the chamber pressure Pc are read in S82, and the count value of the brake operation time ΔTb is reset in S83 of FIG. Next, in S84, the brake switch signal B
It is determined whether sw becomes 1, and when Bsw = 1 (S84, YES), the process proceeds to S85, and the vehicle speed V (ΔTb) at that time is read. In the next S86, the vehicle speed V
It is determined whether or not (ΔTb) has become zero, and if it does not become zero (S86, YES), the vehicle speed V (ΔT
The cycle ΔT is added to the brake operation time ΔTb every sampling cycle of b) to count the brake operation time ΔTb. Then, Bsw = 1 (S84, YE
S) and while the vehicle speed V (ΔTb) is not zero (S
86, YES), the flow of S84 to S87 is repeated, and when the vehicle speed V (ΔTb) becomes zero (S86, N).
O), the flow proceeds to S88, and the counting of the brake operation time ΔTb ends. Next, in S89, it is determined whether or not the brake operation time ΔTb is 3 seconds or more. If ΔTb is 3 seconds or more (S89, YES), the process proceeds to S90 in FIG.
If Tb is less than 3 seconds (S89, NO), the process returns to S83 to reset the count value of ΔTb.

In S90 of FIG. 18, the deceleration G ₀ for 1 second at the initial stage of deceleration, the deceleration G _M for 1 second at the intermediate point of ΔTb, and the deceleration G _E for 1 second immediately before the stop are calculated. To do. In FIG. 19, ΔG is a threshold value for determining the difference in deceleration, and D ₁ , D ₂ , Dg, and Dt are pattern coefficients. The larger the value of this pattern coefficient, the more dangerous it is, and it is determined that the more rapid deceleration immediately before the stop, the more dangerous the deceleration (Dg = D ₁ + 3 × D ₂ ). And
The driving characteristic variable DK of the driver is calculated by the equation DK = K ₁ (Dt +
Calculate from Dg) + K ₂ · DK. However, K ₁ + K ₂ =
1.0, K ₁ <K ₂ .

After the driving characteristic variable DK is obtained as described above, the target boost ratio TGK is read from the map shown in S92 of FIG. 20, and this target boost ratio TGK is read.
Based on the above, the control signal output routine similar to that in FIG. 10 may be executed.

Also in this embodiment, the brake pedal force is indirectly learned by learning the driving characteristics of the driver based on the deceleration pattern of the vehicle body during braking, and the assist force by the sub-booster 4 is changed based on the learning result. Therefore, it is possible to correct the individual difference of the driver that appears when the brake pedal 1 is depressed, and to obtain a reliable braking force.

FIG. 22 is an overall system diagram showing an embodiment of the brake control device shown in the block diagram of FIG. 21 of the second invention.

In FIG. 22, a brake pedal force sensor 46 for detecting the pedal force of the brake pedal 1 is added to the configuration of FIG.

The flowcharts of FIGS. 23 to 25 show the brake pedal force only when the inter-vehicle distance L at the start of braking and the pedal depression time ΔT from the accelerator pedal 44 to the brake pedal 1 are shorter than predetermined values. It shows an embodiment in which learning is executed and the assisting force by the sub-booster 4 is changed based on the learning result.

First, in S101 of FIG. 23, the system is initialized. That is, the memory value of the variable DK representing the driving characteristics of the driver is read and each variable is reset. The above memory values are saved in the memory when the power is turned off. The variables to be reset are the brake operation time ΔTb and the average brake pedal force AVFb.

23 and 24 show the contents of the data input routine. That is, in S102, the accelerator switch signal Asw, the brake switch signal Bsw, and the chamber pressure Pc are read, and in S103 of FIG. 24, the count value of the pedal depression time ΔT is reset.
Next, when it is determined in S104 that the accelerator switch signal Asw has become 0 (S104, YES), S1
The routine proceeds to 05 to read the inter-vehicle distance L and start counting the pedal depression time ΔT. Then, until it is determined in S106 that the brake switch signal Bsw becomes 1, it is confirmed in S107 that the accelerator switch signal Asw is kept at 0 (S107, YES), and the brake switch signal Bsw becomes 1. At the point (S10
6, YES), and the counting of the pedal depression time ΔT is ended in S108.

Next, in S109, it is determined whether or not the learning area. As shown in the figure, this learning region is set in advance under the condition that the inter-vehicle distance L at the start of braking and the pedal change time ΔT from the accelerator pedal 44 to the brake pedal 1 are each shorter than a predetermined value. Keep it. If it is the learning area (S109, YES), S1
At 10, the counting of the brake operation time ΔTb is started.
In the next S111, the brake pedal force Fb is read, and S11
At 2, the value of the brake pedal force Fb is added. next,
In S113, it is determined whether or not the brake switch signal Bsw has become 0, and when Bsw = 0, (S113,
NO), and the counting of the brake operation time ΔTb ends (S114).

Next, in S115 of FIG. 25, the brake pedal force Fb
Is divided by the brake operation time ΔTb to calculate the average brake pedal force AVFb, and driving characteristic learning is executed in the next S116. In S116, the average brake pedal force AVF
The coefficient Db is read from b and the driving characteristic variable D of the driver is read.
K is obtained from the equation DK = K ₁ · Db + K ₂ · DK. However, K ₁ + K ₂ = 1.0 and K ₁ <K ₂ .

After the driving characteristic variable DK is obtained as described above, the target boost ratio TGK is read from the map shown in S92 of FIG. 20, and this target boost ratio TGK is read.
Based on the above, the control signal output routine similar to that in FIG. 10 may be executed.

In this embodiment, the learning of the brake pedal force Fb is limited to the preset learning region from the inter-vehicle distance L at the start of braking and the pedal depression time ΔT from the accelerator pedal 44 to the brake pedal 1. Since it is performed, it is possible to obtain a reliable braking force according to the degree of danger of appearing in how to press the brake pedal 1 during braking.

When the brake pedal force is learned, the brake pedal force may be detected from the seat pressure applied to the driver seat when, for example, the driver depresses the brake pedal during braking. Further, in a vehicle configured to operate the parking brake with a foot pedal, it is possible to estimate the brake pedal force from the pedal force of the parking brake pedal when the vehicle is stationary.

Further, prior to changing the assisting force according to the driving characteristics of the driver, the friction coefficient μ of the traveling road surface is
The assist force may be changed in advance according to the above, or according to the load.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a brake control device according to a first invention.

FIG. 2 is an overall system diagram showing a specific example of a brake control device according to the first invention.

FIG. 3 is a flowchart showing a main routine of a control example of the brake control device according to the first invention.

FIG. 4 is a flowchart showing a part of the contents of steps S1 and S2 of FIG.

5 is a flowchart showing the rest of the contents of step S2 of FIG.

FIG. 6 is a flowchart showing an example of the contents of step S3 of FIG.

FIG. 7 is a flowchart showing the contents of step S4 of FIG. 3 following FIG.

8 is a flowchart showing another example of the contents of step S3 of FIG.

9 is a flowchart showing the contents of step S4 of FIG. 3 following FIG.

FIG. 10 is a flowchart showing the contents of step S5 of FIG.

FIG. 11 is a brake control device 1 according to a second invention.
Block diagram showing the configuration of the embodiment

12 is an overall system diagram showing a specific example of the brake control device shown in FIG.

13 is a flowchart showing the contents of a driving characteristic learning routine executed by the control unit shown in FIG.

FIG. 14 is a flowchart showing the contents of the boost magnification determination routine.

FIG. 15 is a flowchart showing the contents of the control signal output routine.

16 is a flowchart showing a part of contents of a system initialization routine and a data input routine executed by the control unit of FIG.

FIG. 17 is a flowchart showing the contents of the data input routine following FIG.

FIG. 18 is a flowchart showing the contents of a deceleration calculation routine following FIG.

FIG. 19 is a flowchart showing the contents of a driving characteristic learning routine following FIG.

FIG. 20 is a flowchart showing the contents of a boost magnification determination routine following FIG.

FIG. 21 is a block diagram showing the configuration of another embodiment of the brake control device according to the second invention.

22 is an overall system diagram showing a specific example of the brake control device in FIG. 21.

23 is a flowchart showing a part of the contents of a system initialization routine and a data input routine executed by the control unit of FIG.

24 is a flowchart showing the contents of the data input routine following FIG. 23.

FIG. 25 is a flowchart showing the contents of a driving characteristic learning routine following FIG. 24.

[Explanation of symbols]

 1 Brake Pedal 2 Master Cylinder 3 Main Booster 4 Sub Booster 7,12 Diaphragm 8,13 Diaphragm Chamber 9,15 Check Valve 14 Air Chamber 16 Control Valve (Vacuum Valve) 17 Control Valve (Atmospheric Pressure Valve) 20 Control Unit 25 Disc Brake Device 41 Brake switch 42 Vehicle speed sensor 43 Pressure sensor 44 Accelerator pedal 45 Accelerator switch 46 Brake pedal force sensor 47 Inter-vehicle distance sensor

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akira Iwamoto No. 3 Shinchi, Fuchu-cho, Aki-gun, Hiroshima Mazda Co., Ltd. Inside the company (72) Inventor Minsei Hirasawa, 3-1, Shinchi, Fuchu-cho, Aki-gun, Hiroshima Prefecture Mazda Co., Ltd. (72) In-house, Yuya Tanaka, 3-1, Shinchi, Fuchu-cho, Aki-gun, Hiroshima Prefecture Mazda Corporation

Claims (11)

[Claims] 1. An assisting means for assisting a braking force generated by a driver's operation of depressing a brake pedal, an assisting force varying means for changing an assisting force generated by the assisting means, and a first detection for detecting a vehicle speed. Means, second detecting means for detecting the distance between the own vehicle and the obstacle, pedal change time measuring means for measuring the change time from the accelerator pedal to the brake pedal at the time of braking, and at the time of braking Driving characteristic learning means for learning the driving characteristic of the driver based on the vehicle speed and the obstacle distance detected by the first and second detecting means, and the pedal change time measured by the measuring means; The assist amount determining means for determining the assist amount based on the driving characteristics learned by the means, and the assist amount determining means. Control device for a brake, wherein the control means for controlling the assisting force variation means based on the determined assist amount, to become equipped with. 2. The learning of the driving characteristics of the driver by the learning means is a ratio of the standard pedal depression time preset from the vehicle speed and the obstacle distance to the pedal depression time measured by the measuring means. The brake control device according to claim 1, wherein the brake control device is performed based on 3. By learning the driving characteristics of the driver,
The brake control device according to claim 2, wherein the habit of the driver's operation of depressing the brake pedal is determined. 4. By learning the driving characteristics of the driver,
3. The brake control device according to claim 2, wherein a reaction speed of danger avoidance of the driver is determined. 5. The brake control device according to claim 3, wherein the habit of the driver is determined based on a forehead map indicating a relationship between a vehicle speed and an obstacle distance. 6. The brake control device according to claim 3, wherein the assist force is increased for a driver who has a tendency to reduce an inter-vehicle distance. 7. The brake control device according to claim 3, wherein the assist force is increased for a driver who tends to delay a reaction to an obstacle. 8. An assisting means for assisting a braking force generated by a driver's operation of depressing a brake pedal, an assisting force varying means capable of changing the assisting force generated by the assisting means, and a brake pedaling force for learning a brake pedaling force. A learning unit; an assist amount determining unit that determines an assist amount based on learning of the brake pedal force by the learning unit; and a control unit that controls the assist force varying unit based on the assist amount determined by the assist amount determining unit, A brake control device comprising: 9. A deceleration pattern detecting means for detecting a deceleration pattern of a vehicle body during brake operation, wherein learning of the brake pedal depression force is performed based on the deceleration pattern detected by the deceleration pattern detecting means. The brake control device according to claim 8. 10. An obstacle distance detecting means for detecting a distance between the own vehicle and an obstacle, and a pedal stepping time measuring means for measuring a stepping time from the accelerator pedal to the brake pedal during braking. The brake pedal stepping force is learned when the obstacle distance detected by the obstacle distance detecting means and the pedal stepping time measured by the pedal stepping time measuring means are relatively short. The brake control device according to claim 8. 11. A plurality of assisting means for assisting a braking force generated by a driver's operation of depressing a brake pedal are connected in a tandem type and are interposed between the brake pedal and a master cylinder. A control device for a brake, wherein an assist force generated from at least one of the assist means is changed by controlling a negative pressure and an atmospheric pressure applied to the at least one assist means.