JP2789892B2 - Vehicle braking ability determination device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle braking capability judging device for judging the braking capability of a vehicle brake (also referred to as braking effectiveness).

[0002]

2. Description of the Related Art The braking ability of a vehicle brake (hereinafter simply referred to as braking ability) is not always normal. For example, heavy braking during high-speed running, continuous braking on long downhill roads, and the like.
Heat fade due to flooding of the friction surface of the brake, etc.
Water fade, vapor lock, and the like occur, and the braking ability decreases from a normal value. Therefore, it is ideal to detect the fact that the braking ability has decreased at an early stage and inform the driver of the fact.

[0003] Based on such circumstances, the following vehicle braking capability determination device has already been proposed. This is a vehicle braking capability determination device that determines the braking capability of the brake using the current mismatch state between the deceleration generated in the vehicle body due to the action of the brake and the brake operating force.

A conventional example of this is disclosed in Japanese Patent Publication No. 51-4 / 1973.
No. 2372. This is because the deceleration generated in the vehicle body and the brake pressure generated in the brake at the time of braking the vehicle are sequentially detected, and if the deceleration detected at the same time does not match the brake pressure, the braking capacity decreases from the normal value. This is a vehicle braking ability determination device that determines that the vehicle braking has been performed. That is, the "inconsistent state between deceleration and brake operation force" is acquired as an inconsistent state between deceleration and brake pressure, and the braking ability is determined using only this.

[0005]

However, when this conventional device is used, it is not always the case that a correct braking ability judgment is made. In this conventional device, the braking capacity is determined only from the mismatch state between the deceleration and the brake pressure. However, the mismatch state is not always determined only by the current value of the braking capacity, but is determined by other factors, for example, the mismatch. This is because a detection error of a sensor that detects parameters such as deceleration and brake pressure necessary for obtaining the matching state, and a temporary change in vehicle motion are also affected. Therefore, this conventional apparatus has a problem that the accuracy of determining the braking ability cannot be sufficiently increased. The present invention has been made to solve this problem.

[0006]

According to the present invention, there is provided a vehicle braking ability determining apparatus including the above-mentioned inconsistent state acquiring means and braking ability determining means. An operation history acquisition unit is provided, and the braking capability determination unit performs braking using not only the current mismatch state acquired by the mismatch state acquisition unit but also the brake operation history acquired by the operation history acquisition unit. The gist is that the ability is determined.

[0007] The inconsistent state acquiring means may acquire the inconsistent state between the deceleration and the brake operation force itself. It can also be obtained. The parameters include, for example, an inconsistent state between the deceleration and the brake pressure, an inconsistent state between the vehicle body-wheel force acting between the vehicle body and the wheel in the vertical direction of the vehicle body and the brake operating force, and a vehicle body-wheel state. An inconsistent state between the inter-force and the brake pressure can be selected.

The mismatch between the deceleration (hereinafter referred to as the actual deceleration in relation to the ideal deceleration described later) and the brake operating force or the brake pressure is, for example, the actual deceleration of the vehicle body and the ideal deceleration (braking). It can be obtained as a deviation from the actual brake operation force or deceleration expected to occur on the vehicle body under the brake pressure when the performance is normal, and a vehicle body-wheel force (hereinafter, described later). An inconsistent state between the actual vehicle body-wheel force and the brake operating force or the brake pressure in the relationship with the ideal vehicle body-wheel force is, for example, the ideal vehicle body-wheel force (braking ability is not the actual vehicle body-wheel force). (A force that is expected to act between the vehicle body and the wheels under the actual brake operation force or the brake pressure under normal conditions).

[0009] "Brake operation history" is, for example,
It is obtained as a past cumulative value of a deviation from the actual vehicle deceleration limit deceleration (for example, the maximum value of the deceleration at which the braking capacity does not decrease even if the brake operation is continued for a certain period of time under each vehicle speed). , The time during which the brake operation is substantially continued, that is, the substantially continuous operation time.

[0010] The vehicle braking ability judging device according to the present invention can be used in combination with, for example, the following device. That is, a device for informing the driver that the braking capacity determination value has decreased from the normal value (including a device for also informing the driver of the deviation of the braking capability determination value from the normal value),
When the judgment value of the braking capacity is lower than the normal value, it is used in combination with a device that enhances the effect of the engine brake or generates a brake pressure higher than normal to compensate for the reduced braking capacity. You can do it.

[0011]

[Function] Since the current value of the braking capacity is determined by the operation history of the brake, if the braking capacity is determined by considering not only the current inconsistency state of the vehicle deceleration and the brake operation force but also the operation history of the brake, The determination accuracy is improved as compared with the case where the braking ability is determined only from the current mismatch state.

[0012] Based on this fact, in the vehicle braking ability judging device according to the present invention, the inconsistent state acquiring means acquires the inconsistent state between the vehicle body deceleration and the brake operating force,
The operation history acquisition unit acquires the brake operation history, and the braking capability determination unit determines the braking capability not only using the current inconsistency between the vehicle deceleration and the brake operation force but also using the brake operation history. .

[0013]

Therefore, according to the present invention, the effect of improving the accuracy of determining the braking ability can be obtained. In particular, if the determination result is effectively used for vehicle braking, an effect is obtained that the vehicle braking can be appropriately performed in relation to the braking ability.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A braking capacity compensating apparatus including a braking capacity judging apparatus according to an embodiment of the present invention will be described below in detail with reference to the drawings.

The braking capability determination apparatus is generally described in terms of the past cumulative value of the deviation of the actual deceleration (hereinafter, referred to as actual G) of the vehicle body from the limit deceleration (hereinafter, referred to as limit G), The actual continuous depressing time of the pedal, the current value of the deviation of the actual G from the ideal deceleration (hereinafter referred to as ideal G), and the actual vehicle-wheel acting between the vehicle and the left and right front wheels in the vertical direction of the vehicle From the current value of the deviation of the force from the ideal vehicle-wheel force, the magnitude of the heat fade (hereinafter simply referred to as “fade”) generated in the brake is determined as one mode of “brake braking capability” in the present invention. It is.

Here, the "limit G" is a maximum value of the vehicle body deceleration which is expected not to cause a brake fade even when the brake is continuously applied for a certain period of time while traveling on a horizontal road and under each vehicle speed. means. Also, "ideal G"
Means a deceleration that is expected to occur in the vehicle body in a non-fade state, on a horizontal road, and under each depression force of a brake pedal. The “ideal vehicle body-wheel force” means a value that is expected to take a vehicle body-wheel force in a non-fade state, on a horizontal road, and under each stepping force of a brake pedal.

The braking capability compensating device including the braking capability determining device, when described roughly, when the braking capability determining device determines that a fade has occurred in the brake, informs the driver of the fact by sound and light. At the same time, the effect of the engine brake and the brake pressure acting on the brake are increased in order to compensate for the decrease in the braking capacity due to the occurrence of the fade.

As shown in FIG. 1, the present braking capacity compensating device comprises a brake pedal 10 having a hydraulic booster 12.
The master cylinder 14 is provided in a vehicle that generates a brake pressure on each of the brakes 20 of the left and right front wheels 16 and the left and right rear wheels 18. An accumulator 24 is connected to the hydraulic booster 12, and the accumulator 24 has
The brake fluid is pumped from the reservoir 28 by the pump 26 and accumulated. When the accumulator pressure in the accumulator 24 reaches about 250 kg / cm ² , the relief valve 30 opens to prevent the accumulator pressure from becoming abnormally high.

In the present vehicle, each wheel 16, 18
Wheels 16 and 18 so that the wheels are not locked.
Control (ABS) that controls the brake pressure of the vehicle
When the vehicle starts and accelerates, the output of an engine (not shown) of the vehicle is reduced and the rear wheels 18
Traction control (TR
C) is possible. Therefore, between the master cylinder 14 and each brake 20, a brake pressure control device 32 for electrically controlling the brake pressure of each wheel 16, 18 is provided. The brake pressure control device 32 controls the ABS & TR based on a signal from a stop lamp switch 34 for detecting depression of the brake pedal 10 and a signal from each wheel speed sensor 36 for detecting the wheel speed of each wheel 16, 18.
It is controlled by the C computer 40.

The ABS & TRC computer 40 further includes a pump 26 based on a signal from a pressure sensor 42 for detecting an accumulator pressure in the accumulator 24.
The start / stop of the pump motor 46 that drives the motor is controlled. Specifically, the pressure sensor 42 detects that the accumulator pressure is approximately 150 kg.
/ cm ² or less, the pump motor 4
6 was started, and by detecting that the pressure sensor 42 is the accumulator pressure is increased to about 185 kg / cm ² or more, the pump motor 46 is stopped, thereby, the accumulator pressure of about 150 kg / cm ² to about 185 kg / cm Keep it between ^two .

The ABS & TRC computer 40 also
The throttle opening of the engine is controlled by the TRC throttle computer 50 for traction control. T
The RC throttle computer 50 is, specifically, a main throttle valve 54 interlocked with an accelerator pedal 52.
Main throttle position sensor 5 for detecting the opening of the throttle
6 and a signal from a sub-throttle position sensor 60 for detecting the opening of the sub-throttle valve 58, the opening of the sub-throttle valve 58 is controlled via the sub-throttle actuator 64 in accordance with the signal from the ABS & TRC computer 40. You do it.

The vehicle also has an electronically controlled automatic transmission, and the gear ratio of an automatic transmission (not shown) is controlled via an electronically controlled transmission 70 by an electronically controlled transmission computer (hereinafter simply referred to as an ECT computer). ) 72.

The present braking capacity compensating apparatus includes a braking capacity compensating computer 80. This is a CPU not shown, R
The ROM includes an OM, a RAM, a bus, an input interface, and an output interface. The ROM includes various programs including the programs shown in the flowcharts of FIGS. 2 to 10 and the graphs of FIGS. Various maps such as a map to be stored are stored. The input interface includes the stop lamp switch 34, a vehicle speed sensor 84, a longitudinal G sensor 86 for detecting longitudinal acceleration (hereinafter referred to as longitudinal G) generated in the vehicle, and a vertical direction between the vehicle and the left and right front wheels 16. Piezo sensor 88 and a brake pressure sensor (detecting the brake pressure of each brake 20 or the master cylinder pressure of the master cylinder 14) that detect the body-wheel force acting on the vehicle
90 are connected. On the other hand, the output interface includes the ABS & TRC computer 40, the TRC throttle computer 50, and the ECT computer 7.
2 and a buzzer 94 which is activated to warn the driver that the braking capacity of the brake 20 has dropped from a normal value.
And a parking brake lamp (“PK” in the figure) which is provided on the instrument panel of the vehicle and is lit to inform the driver that the parking brake of the vehicle is in the operating state.
96 (referred to as “B lamp”).

The operation of the braking capacity compensation computer 80 will be described in detail with reference to the drawings. When its power is turned on, the braking capability compensating computer 80 executes the respective routines shown in FIGS. 2 to 7 in order, and repeatedly executes the routines at fixed minute intervals (for example, 8 msec).

The routine of FIG. 2 is based on the fact that the brake 20 is often heavily used especially at high speeds and fading is likely to occur. It is a program to determine.

In this routine, first, at step S1
In the following (simply represented by S1; the same applies to other steps), it is determined whether or not the stop lamp switch (represented by "STP switch" in the drawing) 34 is in the ON state, that is, the brake pedal 10 is depressed. Is determined. Otherwise, the determination is NO and one cycle of this routine ends, but if so, the determination is YES, and in S2, the vehicle speed sensor 8
Vehicle speed V is calculated based on a signal from the 4, it whether or not the reference vehicle speed greater than or equal _to V ₀ is determined. The reference vehicle speed V ₀ is based on the fact that the brake 20 is unlikely to fade when the vehicle speed V is low, and is, for example, 40 km / h. Therefore, if the vehicle speed V is smaller than the reference vehicle speed V ₀ and the determination is NO, one execution of the present routine ends, and the vehicle speed V
Is equal to or higher than the reference vehicle speed V ₀ , and if the determination is YES, the steps after S3 are executed.

In S3, the limit G corresponding to the vehicle speed V is the relationship between the vehicle speed V and the limit G (the relationship shown in the graph of FIG. 11).
0 stored in the ROM). Thereafter, in S4, the actual G is calculated based on the signal from the front and rear G sensor 86, and the deviation G of the actual G from the limit G is calculated.
Is calculated, and in S5, the deviation G is added to the current value of the cumulative deceleration (hereinafter, simply referred to as the cumulative G) to update the current value of the cumulative G. In S6, the cumulative G (this is the “brake Is larger than a threshold value. Otherwise, the determination is NO and one cycle of this routine ends, but if so, the determination is YES and R
The AM fade flag A is turned ON, and one cycle of this routine ends.

The actual G when heavy braking is performed at high speeds changes, for example, as shown in the graph of FIG.

The routine shown in FIG. 3 is based on the fact that brake operations are frequently performed particularly on long downhill roads, and that the brake pedal 10 is likely to fade.
Is a program for determining the braking capacity from the substantially continuous stepping-on time.

[0030] In this routine, first, in S11, whether the current value of the vehicle speed V is the reference vehicle speed greater than or equal _to V ₀ is determined. Otherwise, the determination is NO and one cycle of this routine ends, but if so, the determination is YES, and in S12, it is determined whether the stop lamp switch 34 is in the ON state. . If so, the determination is YES and a stop lamp counter ("STPK" in FIG.
Is increased by 1; otherwise, the determination is NO and the value of the stop lamp counter is decreased by 1 in S14.

In any case, thereafter, at S15, the current value of the stop ramp counter (this is another mode of the "brake operation history" in the present invention) is a threshold value (indicated by "STPKM" in the figure). It is determined whether it is greater than. Otherwise, the determination is NO and one cycle of this routine ends, but if so, the determination is YES, and in S16, the fade flag B of the RAM is turned ON and one cycle of this routine is executed. Ends.

The threshold value of the stop ramp counter can be set, for example, so that the value of the stop ramp counter reaches the threshold value when the brake pedal 10 is continuously depressed for about 300 seconds.

FIG. 15 is a graph showing an example of a state in which the value of the stop lamp counter exceeds a threshold value due to frequent braking during traveling on a long downhill road.

The routine of FIG. 4 determines the braking ability from the current value of the deviation of the actual G from the ideal G based on the fact that the depressing force of the brake pedal 10 does not match the actual G if the braking ability decreases. It is a program.

[0035] First, in this routine, in S20, whether the current value of the vehicle speed V is the reference vehicle speed greater than or equal _to V ₀ is determined, one of the routine determination becomes NO if not Is completed, and if so, the determination is YES, and in S21, it is determined whether the stop lamp switch 34 is in the ON state. Otherwise, the determination is NO and one cycle of this routine ends, but if so, the determination is YES and S
At 22, the brake pressure P is detected by the brake pressure sensor 90, and at S23, the ideal G corresponding to the brake pressure P is determined by the relationship between the brake pressure P and the ideal G (FIG. 1).
2 is stored in the ROM of the braking capacity compensation computer 80). Subsequently, in S24, the actual G is detected by the front and rear G sensor 86.

Thereafter, in step S25, a deviation G of the ideal G from the actual G is calculated, and in step S26, the deviation G is calculated.
It is determined whether or not (this is one mode of the “mismatch state” in the present invention) is larger than a threshold value. Otherwise, the determination is NO and one cycle of this routine ends, but if so, the determination is YES and S27
, The fade flag C of the RAM is turned ON, and one execution of this routine ends.

An example of how the deviation G of the ideal G from the actual G exceeds the threshold value due to the fading of the brake 20 is shown in the graph of FIG.

The routine shown in FIG. 5 is a program for determining the braking ability from the current value of the deviation of the actual value of the vehicle body-wheel force from the ideal value. In this routine, first, S30
, The current value of the vehicle speed V is equal to the reference vehicle speed V _0.
It is determined whether or not it is above, otherwise, the determination is N
The result is O, and the execution of this routine is completed. If so, the determination is YES, and in S31, it is determined whether the stop lamp switch 34 is in the ON state. Otherwise, the determination is NO and one cycle of this routine ends, but if so, the determination is YES
In S32, the stop lamp switch 34
The ON time T during which is maintained in the ON state is calculated, and it is determined whether or not the ON time T has exceeded the maximum time _TMAX .
If so, the determination is YES and one execution of this routine ends, but if not, the determination is NO and
In S33, the brake pressure P is detected by the brake pressure sensor 90.

Thereafter, in S34, the ideal value expected to take the vehicle-wheel force under the brake pressure P is as follows:
The relationship between the brake pressure P and the vehicle body-wheel force F (the relationship represented by the graph of FIG.
0 stored in the ROM). Subsequently, in S35, the vehicle body is detected by the piezo sensor 88.
The actual value of the wheel-to-wheel force is detected, and in S36, a deviation from the actual value of the ideal value is calculated. In S37, the deviation (this is another aspect of the "mismatch state" in the present invention) is a threshold. It is determined whether it is greater than the value. Otherwise, the determination is NO and one cycle of this routine ends, but if so, the determination is YES and S
At 38, the fade flag D of the RAM is turned ON, and one execution of this routine ends.

[0040] It should be noted that, although the ON time T is so as not to be substantial execution of the routine even at the time of vehicle braking if the maximum time T _MAX or more, this is, ON time T is the maximum time T _{At the} time when the value becomes _MAX or more, the inclination angle of the vehicle body is stabilized, and the force between the vehicle body and the road surface is also stabilized.
This is because normal operation cannot be guaranteed if the input to the input becomes stable.

FIG. 17 is a graph showing an example of how the deviation of the ideal value of the vehicle body-wheel force from the actual value exceeds the threshold value due to the occurrence of fade in the brake 20.

The four routines described above are designed so that if the respective fade flags A to D are turned on prior to the execution of the four routines, the execution thereof is omitted.

Further, each of the fade flags A to D is once turned ON.
Then the vehicle's ignition switch is set to O
When the vehicle is operated by the FF, the vehicle is left as it is until the vehicle is left for a reference time or longer, and then is turned off.

The routine shown in FIG.
This is a program for judging the degree of fade generated in the brake 20 from the ON / OFF state of D, that is, the warning level, and controlling the buzzer 94 and the parking brake lamp 96 according to the warning level. The warning level has four levels from 1 to 4, and the higher the fade, the higher the warning level (the higher the level value). In addition, 4
The significance of the fade flags A to D is considered to be C>A>B> D.

In this routine, first, in S101, it is determined whether or not all of the fade flags A to D are turned on. If so, the determination is YES, and
In S102, the warning level is set to 1, and in S103, the duty ratio of the buzzer 94 (representing the length of each continuous operation time when the buzzer 94 is operated intermittently; represented by "DUTY" in the figure) is 50. %.

If all of the fade flags A to D have not been turned ON, the determination in S101 is NO, and
At 4, it is determined whether all of the fade flags A to C have been turned ON. If so, the determination is YES
In S105, the warning level is set to 2 and S
At 106, the duty ratio of the buzzer 94 is set to 30%.

If all of the fade flags A to C have not been turned ON, the determination in S104 is NO, and S10
At 7, it is determined whether or not the fade flags A and C are ON. If so, the determination is YES, the warning level is set to 3 in S108, and S10
In 9, the duty ratio of the buzzer 94 is set to 20%.

If the fade flags A and C are not turned on, the determination in S107 is NO, and in S110, it is determined whether any one of the fade flags A to D is turned on. If so, the determination is YE
S, the warning level is set to 4 in S111,
In S112, the duty ratio of the buzzer 94 is 10%
It is said.

If none of them, S110
Is NO, and one execution of this routine ends. In this case, it is determined that the warning level is 5, that is, no fade occurs in the brake 20.

If the warning level is one of 1 to 4, in S113, S103, S106, S10
9 or the buzzer 94 is driven in accordance with the duty ratio determined in S112, and in S114, the parking brake lamp 96 is turned on and off. Using a dedicated buzzer 94 and parking brake lamp 96
The driver is warned that a fade has occurred in the brake 20 by diverting. However, the blinking pattern of the parking brake lamp 96 is constant regardless of the value of the warning level. This completes one execution of this routine.

The routine shown in FIG. 7 is a program for compensating for a decrease in the braking capacity due to a fade generated in the brake 20. In this routine, first, in S201, it is determined whether the current value of the warning level is 1 to 4. If the warning level is 1, S202
, Throttle control is performed. Specifically, FIG.
In step S301, a signal indicating that the sub-throttle valve 58 is fully closed is output from the TRC.
It is supplied to the throttle computer 50. As a result, the effect of the engine brake is improved more than usual, and the apparent braking ability is improved.

Subsequently, ECT control is performed in S203 of FIG. Specifically, as shown in the flowchart of FIG. 9, in S401, the vehicle speed V is set to 100 km / h.
It is determined whether or not it is above, otherwise, the determination is N
In step S402, a signal indicating that the automatic transmission is downshifted to the second speed is input to the EC.
The signal is supplied to the T computer 72, and if so, the determination is YES, and a signal to the effect that the automatic transmission cuts the overdrive (represented by “O / D” in the figure) is supplied to the ECT computer 72. In any case, the effect of the engine brake is improved more than usual, and the apparent braking ability is improved.

The state of the automatic transmission is changed depending on whether the vehicle speed V is in the high speed range or the low speed range, because the automatic transmission is immediately downshifted to the second speed while the vehicle speed V is in the high speed range. This is because the engine may overrun.

Thereafter, the brake booster control is performed in S204 of FIG. Specifically, as shown in the flowchart of FIG. 10, a signal indicating that the pressure sensor 42 continues to operate the pump motor 46 ignoring that the accumulator pressure has become about 185 kg / cm ² or more is ignored. It is supplied to the ABS & TRC computer 40. As a result, the accumulator pressure increases to about 250 kg / cm ^2, which is the relief pressure of the relief valve 30, and the assisting limit of the hydraulic booster 12 is set higher than usual. Therefore, the boosting effect of the hydraulic booster 12 can be enjoyed even in the pedaling force range higher than the normal assisting limit, and the brake pressure generated in each brake 20 is made higher than usual. However, long-term increases in brake pressure will actually increase fades.However, as soon as the driver learns that a fade has occurred, it is normal to shift to an evacuation operation to stop the vehicle at an appropriate place, The evacuation operation is performed before the fade increases so much due to the increase in the brake pressure, and the evacuation operation allows the driver to generate the largest possible vehicle deceleration under the fade and stop the vehicle quickly. This completes one execution of this routine.

On the other hand, when the warning level is 2, the determination in S205 in FIG. 7 is NO until 200 seconds elapse after the warning level is determined to be 2 for the first time, and the processing in S203 and subsequent steps is performed. Step executed EC
The T control and the brake booster control are performed. After 200 seconds have elapsed since the warning level was determined to be 2 for the first time, the determination in S205 becomes YES and S20
The following two steps are performed.

When the warning level is 3, 200 seconds after the warning level is determined to be 3 for the first time.
Until c has elapsed, the determination in S206 is NO and S
At 204, the brake booster control is performed, but 200 seconds after the warning level is determined to be 3 for the first time.
After the lapse of c, the determination in S206 becomes YES, and S
Steps 203 and below are executed.

When the warning level is 4 or 5, the execution of this routine ends without performing any control.

That is, in this embodiment, when the warning level is 1, a warning is given by the buzzer 94 and the parking brake lamp 96, and the effect of the engine brake by the throttle control and the ECT control is increased.
When the warning level is 2, the warning, the increase in the effect of the engine brake by the ECT control, and the increase in the brake pressure are performed in the early stage when the warning level is 2. In the latter period, a warning is issued, the effect of the engine brake by the throttle control and the ECT control is increased, and the brake pressure is increased. When the warning level is 3, the warning is issued in the early stage. , The brake pressure is increased, and in the later period,
The warning, the effect of the engine brake by the ECT control are increased, and the brake pressure is increased.
If, only a warning is issued.

As is apparent from the above description, in this embodiment, the stop lamp switch 34, the vehicle speed sensor 84, the front-rear G sensor 8
6, the routine of FIG. 2, the routine of FIG. 3, the routine of FIG. 4, the routine of FIG. 5, the S1 of FIG.
01, S102, S104, S105, S107, S1
The part that executes 08, S110, and S111 constitutes the braking ability determination device. The front and rear G sensor 86, the piezo sensor 88,
4 and S30 to S25 in FIG. 4 and S30 to S25 in FIG.
The vehicle speed sensor 84, the front-rear G sensor 86, and the stop lamp switch 34 constitute the inconsistent state acquisition means in cooperation with the part that executes step S36. The operation history obtaining means is configured in cooperation with the part that executes S11 to S14 of FIG. 5, and the braking capability compensation computer 80 uses S6, S7 of FIG. 2, S15, S16 of FIG. 3, S26, S27 of FIG. S
37, S38, S101, S102, S104 in FIG.
The part that executes S105, S107, S108, S110, and S111 constitutes a braking ability determination unit.

Although the embodiment of the present invention has been described in detail with reference to the drawings, various modifications and improvements may be made based on the knowledge of those skilled in the art without departing from the scope of the claims. The present invention can be carried out in the mode in which it is performed.

[Brief description of the drawings]

FIG. 1 is a system diagram showing a braking capability compensating device including a braking capability determining device according to one embodiment of the present invention.

FIG. 2 is a flowchart showing a routine used by the braking capacity compensation computer of FIG.

FIG. 3 is a flowchart illustrating a routine used by the braking capacity compensation computer of FIG. 1;

FIG. 4 is a flowchart showing a routine used by the braking capacity compensation computer of FIG. 1;

FIG. 5 is a flowchart showing a routine used by the braking capacity compensation computer of FIG. 1;

FIG. 6 is a flowchart showing a routine used by the braking capability compensation computer of FIG. 1;

FIG. 7 is a flowchart showing a routine used by the braking capacity compensation computer of FIG. 1;

FIG. 8 is a flowchart showing S202 of FIG. 7;

FIG. 9 is a flowchart showing S203 of FIG. 7;

FIG. 10 is a flowchart showing S204 of FIG. 7;

11 is a graph showing a relationship between a vehicle speed V and a limit deceleration G used by the braking capacity compensation computer of FIG.

12 is a graph showing a relationship between a brake pressure P and an ideal deceleration G used by the braking capacity compensation computer of FIG.

FIG. 13 is a graph showing a relationship between a brake pressure P and an ideal vehicle body-wheel force F used by the braking capacity compensation computer of FIG. 1;

FIG. 14 is a graph showing an example in which the actual deceleration changes in the braking ability compensating device of FIG. 1;

FIG. 15 is a graph showing an example in which the value of a stop lamp counter changes in the braking capacity compensator of FIG. 1;

FIG. 16 is a graph showing an example in which the deviation deceleration changes in the braking ability compensating device of FIG. 1;

FIG. 17 is a graph showing an example in which the relationship between the ideal value and the actual value of the vehicle body-wheel force changes in the braking ability compensating device of FIG. 1;

[Explanation of symbols]

 Reference Signs List 10 brake pedal 20 brake 34 stop lamp switch 80 braking capability compensation computer 84 body speed sensor 86 front and rear G sensor 88 piezo sensor 90 brake pressure sensor 94 buzzer 96 parking brake lamp

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B60T 17/22 B60T 8/60

Claims (1)

(57) [Claims] An inconsistent state acquiring means for acquiring an inconsistent state between a deceleration generated in a vehicle body due to the action of a brake and a brake operation force, and a current inconsistent state acquired by the inconsistent state acquiring means. A braking ability determining means for determining the braking ability of the brake by using an operation history acquiring means for acquiring a braking operation history of the brake by a driver; and
The braking capability is determined using not only the current inconsistent state acquired by the inconsistent state acquiring means but also the brake operation history acquired by the operation history acquiring means. Vehicle braking ability determination device.