JP3219479B2 - Vehicle slip control 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 slip control device for a vehicle, which prevents a drive wheel from slipping when the vehicle is accelerating or the like, thereby preventing the acceleration performance from decreasing.

[0002]

2. Description of the Related Art Conventionally, for example, Japanese Patent Application Laid-Open No. Sho 60-104730.
As shown in the publication, by controlling the fuel supply amount based on the driving wheel speed, the driven wheel speed and the engine speed, the control for suppressing the engine torque when the engine speed is low is gently executed. This prevents the drop in the driving wheel speed, thereby controlling the driving wheel speed satisfactorily regardless of the engine speed, suppressing the slip and improving the running stability of the vehicle. Slip control devices are known.

That is, when it is confirmed that the drive wheels are in a slip state, the slip control device cuts fuel in all cylinders when the engine speed is equal to or higher than a preset number, and performs engine rotation. When the number is less than the set number, by partially performing the fuel cut, the engine torque suppression control in the low engine speed region is gently executed, the drop in the drive wheel speed is reduced, and the acceleration and It is configured to suppress the slip of the driving wheels while maintaining the drivability in a good state.

[0004]

As described above, in the case where the number of cylinders whose fuel is cut off is merely changed in accordance with the level of the engine speed, the vehicle 2
At the time of fast starting, there is a problem that it is not possible to effectively prevent the pulsation of the drive wheel speed from being caused by the change in the engine speed.

More specifically, when the vehicle starts in the first speed, as shown in FIG. 8, the slip control of the drive wheels is executed, so that both the engine speed and the drive wheel speed decrease slowly. At the start of the second speed, as shown in FIG. 9, the engine speed drops rapidly, and the driving wheel speed converges to match the driven wheel speed. Since the torque-down response to the control request is lower at the start of the second speed than at the start of the first speed, the drive wheel speed may increase again after the convergence of the drive wheel speed, and then decrease to a region close to the driven wheel speed. There is a problem that the pulsation of the driving wheel speed is generated repeatedly and the running feeling is deteriorated.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problem, and an object of the present invention is to provide a vehicle capable of appropriately executing drive wheel slip control while preventing pulsation of the drive wheel speed at the time of starting the second speed. It is intended to provide a slip control device.

[0007]

The invention according to claim 1 is
A control level setting means for setting a control level of an engine output according to a slip state of a drive wheel, in a vehicle slip control device for suppressing a slip of a drive wheel with respect to a road surface by controlling an output of the engine, , A second-speed start detection means for detecting that the vehicle is in the second-speed start state, and the second-speed start detection means confirming that the vehicle is in the second-speed start state, A correction for correcting the control level set by the control level setting means in the direction of decreasing the engine output when it is confirmed that the engine speed has increased in response to the output signal of the rotation speed detecting means. Means.

According to a second aspect of the present invention, there is provided a slip control apparatus for a vehicle for suppressing the slip of a drive wheel on a road surface by controlling the output of an engine, wherein a control level of the engine output is set according to a slip state of the drive wheel. Control level setting means, a rotation speed detection means for detecting an engine speed, a second speed start detection means for detecting that the vehicle is in a second speed start state, and a second speed start detection means for detecting that the vehicle is in the second speed start state. When it is confirmed that the vehicle is in the start state, and when it is confirmed that the engine speed has dropped in response to the output signal of the speed detecting means, the control level set by the control level setting means is changed. And correction means for correcting the reduction of the engine output in a direction in which the reduction is reduced.

According to a third aspect of the present invention, in the vehicle slip control device according to the first or second aspect, it is determined whether or not the vehicle speed is equal to or higher than a predetermined reference vehicle speed, and the vehicle speed meets the reference vehicle speed. If it is confirmed that there is no vehicle speed, it detects whether the vehicle is in the second speed start state according to the state of the engine speed drop, and if it is confirmed that the vehicle speed is higher than the reference vehicle speed, the vehicle speed and It is configured to detect whether or not the vehicle is in the second speed start state according to the engine speed.

[0010]

According to the first aspect of the present invention, when it is confirmed that the vehicle is in the second speed starting state, the control for suppressing the rising of the engine in response to the changing state of the engine speed is quickly executed. As a result, the pulsation of the driving wheel speed at the second-degree start is effectively prevented, and the slip control of the driving wheels is properly executed.

According to the second aspect of the present invention, when it is confirmed that the vehicle is in the second speed start state, the control for suppressing the drop according to the change state of the engine speed is quickly executed. In addition, the pulsation of the driving wheel speed at the second-degree start degree is effectively prevented, and the slip control of the driving wheels is properly executed.

According to the third aspect of the present invention, when the vehicle is running at a high speed, the vehicle is brought into the second speed starting state based on the detected values of the vehicle speed and the engine speed and a correspondence table or the like set corresponding to the detected values. Whether it is present or not is instantaneously detected. At a low vehicle speed where it is difficult to perform the detection based on the correspondence table or the like, it is detected whether or not the vehicle is in the second speed start state according to the change state of the engine speed.

[0013]

FIG. 1 shows an overall configuration diagram of a vehicle slip control device according to an embodiment of the present invention. This vehicle includes drive wheels 1 and 2 composed of left and right front wheels and driven wheels 3 and 4 composed of left and right rear wheels. The driving force of a V-type six-cylinder engine 5 is controlled by an automatic transmission 6, a differential 7, It is configured to be transmitted to the drive wheels 1 and 2 via left and right drive shafts 8 and 9.

The above-mentioned vehicle has wheel speed sensors 10-1 for detecting rotation speeds (wheel speeds) V1-V4 of the wheels 1-4.
3, a vehicle speed detecting means 14 for detecting a vehicle speed Vr according to the detection signal, a friction coefficient detecting means 15 for detecting a friction coefficient μ of a traveling road based on the vehicle speed Vr and its acceleration, and a road surface of the drive wheels 1 and 2. When the slip amounts S1 and S2 exceed the predetermined threshold value, the engine output is controlled so that the slip amounts S1 and S2 become the target values, and the driving force applied to the drive wheels 1 and 2 is limited. Control means 16 is provided.

The control means 16 includes, as shown in FIG.
Threshold setting means 17 for setting a threshold for slip control;
Slip amount calculating means 18 for calculating the slip amounts S1 and S2 of the driving wheels 1 and 2, slip determining means 19 for determining whether or not to execute the slip control of the driving wheels 1 and 2, and a target value for the slip control Target value setting means 20 for setting T
And a control level calculating means 22 for calculating a control level of a signal output to the output control unit 21 of the engine 5.

The control means 16 includes the engine 5
A second-speed start detecting means 24 for detecting whether or not the vehicle is in a second-speed start state in accordance with a detection signal of a rotational speed detecting means 23 for detecting a rotational speed R of the vehicle. When it is confirmed that the vehicle is in the second-speed start state,
Correction means 25 for correcting the level of the control signal output to the output control section 21, that is, the control level of the engine output
Are provided.

The threshold setting means 17 determines a slip from a threshold table (not shown) according to the vehicle speed Vr detected by the vehicle speed detecting means 14 and the friction coefficient μ of the traveling road detected by the friction coefficient detecting means 15. The first threshold for determining whether to start the slip control and the second threshold for determining whether to continue the slip control are read out as the threshold. is there.

The slip amount calculating means 18 subtracts the vehicle speed Vr detected by the vehicle speed detecting means 14 from the wheel speeds V1 and V2 of the left and right driving wheels 1 and 2, and calculates the slip of the driving wheels 1 and 2. Actual slip amount calculating means for obtaining the amounts S1 and S2; average slip amount calculating means for calculating the average slip amount Sav of both driving wheels 1 and 2 based on the slip amounts S1 and S2; And a maximum slip amount setting means for setting the higher one as the maximum slip amount Shi.

The slip judging means 19 calculates the maximum slip amount Shi obtained by the slip amount calculating means 18.
And the first threshold value for slip determination set by the threshold value setting means 17 to determine whether or not to start the slip control of the drive wheels 1 and 2, and to determine the maximum slip ratio Shi and It is configured to determine whether to continue the slip control by comparing with a second threshold value for slip determination.

The target value setting means 20 calculates a control target value (not shown) according to the vehicle speed Vr detected by the vehicle speed detecting means 14 and the friction coefficient μ of the traveling road detected by the friction coefficient detecting means 15. A target value T of the slip amount of the drive wheels 1 and 2 is read from the table, and the value is output to the control level calculating means 22.

The control level calculating means 22 calculates the deviation EN of the average slip amount Sav from the slip amount target value T.
A control amount calculating means for sequentially integrating values read from a preset basic control amount table as shown in FIG. 3, for example, based on the change rate DEN, and an integrated value of the basic control amount set in advance. By dividing the set value, for example, 100, and cutting off the remainder, as shown in FIG.
Level calculating means for calculating a control level divided into 12 levels.

The signal of the control level calculated by the control level calculating means 22 is output to the output control section 21 of the engine 5, so that the fuel cut control corresponding to the control level is stored in the table shown in FIG. It is executed based on. That is, the slip control is executed by stopping the fuel injection to the cylinder indicated by the number x in the figure.

The second speed start detecting means 24 determines when the slip control is executed at the time of starting according to the output signal of the rotational speed detecting means 23 and the engine speed R is changed from rising to falling. From a predetermined time (for example, 192
Within msec), when it is detected that the engine speed R has dropped from the peak value by a predetermined amount (for example, 350 rpm) or more, it is determined that the vehicle is in the second speed start state.

When the second speed start detecting means 24 confirms that the vehicle is in the second speed start state, the correcting means 25 changes the engine speed R according to the output signal of the rotational speed detecting means 23. Is detected, and the control level is reduced or increased in accordance with the change state.

That is, when the engine speed R drops by a predetermined amount (for example, 75 rpm) from the upper limit peak value by more than a predetermined value (for example, 75 rpm), the correction means 25 determines that the engine speed R has dropped, and determines the control level calculation means 22. When the engine speed R is increased by a predetermined amount (for example, 50 rpm) from the lower limit peak value within a predetermined time (for example, 32 msec), the correction is performed to reduce the control level calculated in the above by a predetermined level set in advance. It is configured to judge that the engine speed R has increased and execute a correction for increasing the control level by a predetermined level.

The correcting means 25 determines whether or not the control level calculated by the control level calculating means 22 is equal to or less than a predetermined level (for example, 5), and the control level is equal to or less than 5. Is performed only when it is confirmed that the control level is larger than 5,
The configuration is such that the increase correction is not performed.

The control of setting the control level by the control means 16 will be described with reference to the flowchart shown in FIG. When the control operation starts, first, in step S1
In, it is determined whether or not the slip control is currently being executed. If the result of this determination is YES, the control level is calculated by the control level calculating means 22 in step S2, and then in step S3 it is determined whether the vehicle is in the second speed start state.

If the result of the determination is NO and it is confirmed that the vehicle is not in the second speed start state, then step S4
In, a signal corresponding to the control level calculated in step S2 is output to the output control unit 21 of the engine 5,
Normal slip control for performing fuel cut on the cylinder set according to the control level is executed.

On the other hand, if YES is determined in step S3, and it is confirmed that the vehicle is in the second speed start state, in step S5, the engine speed R is equal to or more than a predetermined amount (75 rpm) from the upper limit peak value. It is determined whether or not the camera is in a lowered state. If the result of this determination is YES, in step S6, after performing a weight reduction correction for subtracting a predetermined level from the control level, the process proceeds to step S4, where the control level after the weight reduction correction is set. The corresponding signal is output to the output control unit 21.

If the result of the determination in step S6 is NO, the program proceeds to step S7 where the engine speed R
Is determined to be in a blow-up state in which the value has increased by a predetermined amount (50 rpm) or more in a short time from the lower limit peak value. If the result of this determination is YES, in step S8, it is determined whether or not the control level calculated in step S is 5 or less.

If the control level is determined to be 5 or less by the determination in step S8, in step S9, after performing a correction for increasing the control level by adding a predetermined level to the control level, the control proceeds to step S9. Step S
4 and outputs a signal corresponding to the control level after the increase correction to the output control unit 21. On the other hand, step S
If it is confirmed in step 8 that the control level is higher than 5, the above-mentioned reduction correction is not executed and step S4 is executed.
Then, a signal corresponding to the control level calculated in step S2 is output to the output control unit 21.

As described above, when it is confirmed that the vehicle is in the second speed starting state in accordance with the output signal of the rotation speed detecting means 23, the control level calculating means 22 performs the control in accordance with the changing state of the engine speed R. Since the control level of the calculated engine output is configured to be increased or decreased,
The slip control of the drive wheels 1 and 2 can be appropriately performed while effectively preventing the pulsation of the drive wheel speed at the time of fast starting.

That is, as shown in FIG. 7, at time point a, the vehicle moves to 2
When it is confirmed that the vehicle is in the fast-start state, it is determined whether or not the engine speed R has dropped or increased thereafter. Then, when it is confirmed that the engine speed R has been raised, b1, b2,...
By increasing the number of cylinders for which fuel is cut by executing the increase correction to reduce the above control level, it is possible to prevent an increase in the driving wheel speed due to the rising of the engine speed R in advance, thereby driving the vehicle. The slip of the wheels 1 and 2 can be effectively suppressed.

Further, at the time points c1, c2,... When it is confirmed that a drop has occurred in the engine speed R, a decrease correction for decreasing the control level is executed, and the number of cylinders for which fuel is cut is reduced to reduce the engine number. By rapidly increasing the rotational speed R, it is possible to effectively prevent the drive wheel speed from unnecessarily lowering due to the decrease in the engine rotational speed R. As a result, when the automatic transmission 6 is set to the hold mode and when the automatic transmission 6 is instantly shifted up to the start degree, the pulsation of the driving wheel speed as shown in FIG. Can be prevented.

In the above embodiment, it is determined whether or not the control level calculated by the control level calculating means 22 is lower than a predetermined level (for example, 5) which is set in advance. Is executed only when it is confirmed that the increase correction is executed in a state where the fuel cut is performed for many cylinders whose control level is larger than 5 and more increase It is possible to prevent the occurrence of a situation in which the cylinder is cut off by fuel, thereby preventing the engine from stopping or causing a sense of stall.

In the above embodiment, the engine speed R
The vehicle speed Vr is set in advance according to the output signal of the vehicle speed detecting means 14 and is determined to be not less than or equal to the reference speed V0 according to the output state of the vehicle speed detecting means 14. When it is confirmed that the vehicle speed Vr at the time of detecting whether the vehicle is in the second speed start state is equal to or higher than the reference speed V0, the detected values of the engine speed R and the vehicle speed Vr, and the engine speed R It may be configured to determine whether or not the vehicle is in the second-speed start state based on the determination table set in accordance with the vehicle speed Vr. Then, when it is confirmed that the vehicle is in a low vehicle speed (the vehicle speed Vr is less than the reference speed V0) in which it is difficult to make a determination based on the determination table, the vehicle starts in the second speed according to the change in the engine speed R. A determination control for determining whether or not the state is made is executed.

As described above, in the case where it is determined whether or not the vehicle is in the second-speed start state based on the determination table and the detected values of the engine speed R and the vehicle speed Vr, As in the case where it is determined whether or not the engine speed R has dropped by a predetermined amount or more from the peak value, there is an advantage that the above-described determination control can be executed quickly without requiring a long time for the determination.

In the above-described embodiment, the correction for decreasing or increasing the control level by a predetermined level is executed at the time point when the drop and the rise of the engine speed R are detected. The current control level may be maintained until the peak value or the upper limit peak value is detected, so that the control level may be substantially reduced or increased. .

Further, instead of the configuration in which the fuel supply to each cylinder is controlled and the fuel is cut as described above, the engine output is controlled and the slip control of the drive wheels 1 and 2 is executed. The engine output may be controlled by delaying the ignition time, or the engine output may be controlled by combining the fuel cut control and the ignition timing delay control.

Further, the present invention can be applied not only to a vehicle having the automatic transmission 6 but also to a vehicle having a manual transmission. In the vehicle having this manual transmission, it is possible to detect whether the engine speed R is changing or whether the vehicle is in the second speed start state based on the vehicle speed and the engine speed. The second speed start state can also be detected by judging the position of.

[0041]

As described above, according to the present invention, the change state of the engine speed is determined according to the detected value of the engine speed, and the signal output to the output control unit of the engine is determined according to the determination result. , The pulsation of the driving wheel speed due to the decelerating state or the rising of the engine speed at the time of starting the second speed of the vehicle can be prevented. Therefore, there is an advantage that the slip of the drive wheels can be effectively suppressed while preventing the running feeling from being deteriorated due to the pulsation of the drive wheel speed.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing an overall configuration of a vehicle having a slip control device according to the present invention.

FIG. 2 is a block diagram showing a configuration of control means of the slip control device.

FIG. 3 is a chart showing a basic control amount table.

FIG. 4 is a table showing a correspondence table between an integrated value of a control amount and a control level.

FIG. 5 is a table showing a fuel cut table.

FIG. 6 is a flowchart showing control of setting a control level.

FIG. 7 is a time chart showing a control state of an engine output by the control means.

FIG. 8 is a time chart showing a change state of the drive wheel speed at the time of starting the first speed.

FIG. 9 is a time chart showing a change state of the drive wheel speed at the time of starting the second speed.

[Explanation of symbols]

 Reference numerals 1 and 2 Drive wheels 22 Control level setting means 23 Revolution number detection means 24 Second speed start detection means 25 Correction means

Continuation of the front page (51) Int.Cl. ⁷ identification code FI F02D 45/00 362 F02D 45/00 362Q (58) Field surveyed (Int.Cl. ⁷ , DB name) F02D 29/00-29/06 F02D 41/00-45/00 395

Claims (3)

(57) [Claims] A control level setting means for setting a control level of an engine output in accordance with a slip state of a drive wheel in a vehicle slip control device for suppressing a slip of a drive wheel on a road surface by controlling an output of an engine. Rotation speed detecting means for detecting the rotation speed of the engine, and a vehicle
Two-speed start detection hand that detects that both are in the second-speed start state
And the vehicle is in the second-speed start state by the second-speed start detection means.
Is in the state
The engine speed rises in response to the output signal of the stage.
When the control level is confirmed, the control level setting means
And a correcting means for correcting the control level set in (1) in the direction of decreasing the engine output . 2. The road is controlled by controlling the output of the engine.
Slip of the vehicle that suppresses the slip of the drive wheel with respect to the surface
The control unit controls the engine according to the slip condition of the drive wheels.
Control level setting means for setting the control level of the gin output
Rotation speed detecting means for detecting the rotation speed of the engine;
Two-speed start detection hand that detects that both are in the second-speed start state
And the vehicle is in the second-speed start state by the second-speed start detection means.
Is in the state
The engine speed drops according to the output signal of the stage
If it is confirmed that the
Set the control level to mitigate the reduction in engine output
And a correcting means for correcting the slip direction in the vehicle. 3. It is determined whether or not the vehicle speed is equal to or higher than a predetermined reference vehicle speed, and when it is confirmed that the vehicle speed is lower than the reference vehicle speed, the vehicle is driven in accordance with the state of the engine speed drop. Detects whether the vehicle is in a fast-start state, and if it is confirmed that the vehicle speed is equal to or higher than the reference vehicle speed, detects whether the vehicle is in a second-speed start state according to the vehicle speed and the engine speed. 2. The method according to claim 1, wherein
3. The vehicle slip control device according to claim 2 .