JP3099482B2 - Total control system for internal combustion engine output and differential limiting torque - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an integrated engine output and differential limiting torque control system applied to a vehicle equipped with both an internal combustion engine output control system and a differential limiting torque control system.

[0002]

2. Description of the Related Art Conventionally, as an internal combustion engine output control system for reducing and controlling the output of an internal combustion engine when an acceleration slip occurs by throttle control, for example, Japanese Patent Laid-Open Publication No.
An apparatus described in Japanese Patent Application Laid-Open No. 9-209 is known.

A differential limiting torque control system for controlling differential limiting torque in which lateral acceleration is used as input information to increase differential limiting torque as lateral acceleration increases is described, for example, in JP-A-1-106737. Known devices are known.

[0004]

However, in a vehicle equipped with both the conventional internal combustion engine output control system and the differential limiting torque control system, the respective systems are controlled independently. Have the following problems.

[0005] (1) When the internal combustion engine output reduction control is performed based on the occurrence of acceleration slip during turning acceleration in a high lateral acceleration state, if the internal combustion engine output control gain is increased, the internal combustion engine output reduction amount May become too large, and the acceleration may decrease.

(2) In the case of a large-radius turning acceleration in a low lateral acceleration state or the like, when the output reduction control of the internal combustion engine is performed based on the occurrence of the acceleration slip, if the differential limiting torque control gain is increased, the steering characteristic is increased. Understeer becomes strong, which is not preferable in terms of maneuverability.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and is intended to be applied to a vehicle equipped with both an internal combustion engine output control system and a differential limiting torque control system. It is an object of the present invention to achieve both the securing of the acceleration during turning at a high lateral acceleration in an acceleration slip state and the securing of the stability at the time of turning at a low lateral acceleration in an acceleration slip state in an integrated control device for torque.

[0008]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, an integrated control apparatus for controlling the output of an internal combustion engine and the differential limiting torque according to the present invention has a difference between an internal combustion engine output control gain and a normal control state.
The dynamic limiting torque control gain is set to 1 each, and the acceleration slip is
Do not change the sum of the two control gains when
Further, the differential limiting torque control gain is relatively increased in the high lateral acceleration state, and the internal combustion engine output control gain is relatively increased in the low lateral acceleration state.

That is, as shown in the claim correspondence diagram of FIG. 1, an acceleration slip state detecting means a for detecting an acceleration slip state of a driving wheel, and an internal combustion engine output control for reducing and controlling an internal combustion engine output according to the acceleration slip state. A means b, a lateral acceleration detecting means c for detecting a lateral acceleration applied to the vehicle, a differential limiting torque control means d for controlling the differential limiting torque of the left and right driving wheels by including the lateral acceleration in the input information, and of
The internal combustion engine output control gain and differential limiting torque control gain
When each of them is set to 1 and acceleration slip occurs, two controls
Without changing the sum of the gains, the differential limiting torque control gain is increased relative to the internal combustion engine output control gain in the high lateral acceleration state, and the internal combustion engine relative to the differential limiting torque control gain in the low lateral acceleration state. And a gain adjustment control means e for increasing the engine output control gain.

[0010]

[Function] At the time of high lateral acceleration turning in the acceleration slip state,
In the gain adjustment control means e, the internal
Engine output control gain and differential limiting torque control gain
When the acceleration slip occurs, two control gay
The internal combustion engine output control and the differential limiting torque control are performed while the differential limiting torque control gain is relatively increased without changing the sum of the torque. Therefore, in the internal combustion engine output control in which the control gain is relatively low, the internal combustion engine output reduction amount is suppressed to a small value, so that the acceleration performance is secured.

At the time of low lateral acceleration turning in the acceleration slip state, the gain adjustment control means e performs the normal control state.
The internal combustion engine output control gain and differential limiting torque control gain
When each of them is set to 1 and acceleration slip occurs, two controls
The internal combustion engine output control and the differential limiting torque control are performed by relatively increasing the internal combustion engine output control gain without changing the sum of the gains . Therefore, a strong understeer is prevented by the differential limiting torque control in which the control gain is relatively low, and the operability is ensured.

[0012]

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

The configuration will be described.

FIG. 2 is an overall view of a system to which the integrated control device for the internal combustion engine output and the differential limiting torque according to the embodiment of the present invention is applied.

A rear wheel drive vehicle to which the embodiment apparatus is applied includes an engine 1, a transmission 2, a propeller shaft 3, a differential 4, drive shafts 5, 6,
Rear wheels 7 and 8 and front wheels 9 and 10 are provided.

The internal combustion engine output control system corresponding to the internal combustion engine output control means is a system for controlling the engine output by the motor throttle opening so that the rear wheel slip ratio is within an optimum allowable range when an acceleration slip occurs. A mechanical throttle valve 13 that operates in conjunction with an accelerator pedal 12 and a motor throttle valve 15 that is opened and closed by a throttle motor 14
Are arranged in series, and a TC
The motor throttle opening is controlled by drive control based on a command current mi from the S motor drive circuit 16.

The differential limiting torque control system corresponding to the differential limiting torque control means varies the differential limiting torque of the left and right rear wheels 7, 8 by controlling the engagement force on the differential limiting clutch 17 built in the differential 4. A control oil passage 20 is connected to a clutch oil chamber of the differential limiting clutch 17 from an external hydraulic source 18 via a hydraulic control valve 19, and a CSD solenoid drive circuit 21 is connected to the hydraulic control valve 19. The clutch hydraulic pressure, which is the clutch engagement force, is controlled by the drive control based on the command current si from the controller.

The TCS motor drive circuit 16 and CSD
The control command to the solenoid drive circuit 21 is output from a general control unit 22 that performs both the throttle control and the differential limiting torque control. VFR and front left wheel speed VFL from front left wheel speed sensor 24
The right rear wheel speed VRR from the right rear wheel speed sensor 25, the left rear wheel speed VRL from the left rear wheel speed sensor 26, and the lateral acceleration sensor 2
7 (corresponding to lateral acceleration detecting means), the steering angle θ from the steering angle sensor 28, and the yaw rate sensor 2
9 is input as sensor information.

The general control unit 22 has a built-in acceleration slip state calculation program corresponding to acceleration slip state detection means.
Based on R, VFL, VRR, and VRL, a difference between the driving wheel speed and the driven wheel speed as an acceleration slip state amount, a driving wheel speed change rate, a slip ratio, and the like are calculated.

The operation will be described.

(A) Comprehensive control operation of throttle control and differential limiting torque control FIG. 3 is a flowchart showing the flow of the total control operation of the throttle control and the differential limiting torque control performed by the general control unit 22. The steps will be described.

In step 50, it is determined whether or not an acceleration slip state equal to or greater than a control threshold value for performing the TCS throttle control is performed based on the calculation of the acceleration slip state amount.

If the determination in step 50 is NO, the process proceeds to step 51. In step 51, for example, on the basis of the control contents described in Japanese Patent Application Laid-Open No. Only the differential limiting torque control is performed.

When the determination in step 50 is NO, the process proceeds to step 52. In step 52, based on the lateral acceleration corresponding gain characteristic described in the step frame,
Throttle control and differential limiting torque control are performed.

The gain characteristic corresponding to the lateral acceleration is represented by a lateral acceleration
The characteristic is that the differential limiting torque control gain increases relative to the throttle control gain as the YG becomes higher in lateral acceleration, and the differential limiting torque control gain increases as the lateral acceleration YG becomes lower. The characteristic is that the throttle control gain is increased.

Steps 50 and 52 correspond to gain adjustment control means.

(B) Running in the non-acceleration slip state When the vehicle is running in the non-acceleration slip state, the flow proceeds from step 50 to step 51 in FIG. 3, which is described in JP-A-1-106737. Only the normal differential limiting torque control is performed based on the control contents and the like.

Therefore, in the differential limiting torque control, the differential limiting torque control is performed with the optimal control gain set independently, without being controlled simultaneously with the throttle control.

(C) Turning in the Acceleration Slip State When turning in the acceleration slip state, the flow proceeds from step 50 to step 52 in FIG. 3, and in step 52, the control gain is based on the control gain corresponding to the lateral acceleration YG. Thus, throttle control and differential limiting torque control are performed.

For example, when turning at a high lateral acceleration, the throttle control and the differential limiting torque control are performed by increasing the differential limiting torque control gain relatively to the throttle control gain. Accordingly, the acceleration control is ensured by suppressing the engine output reduction amount to a small value in the throttle control in which the control gain is relatively low. Further, under-steer characteristics in a stable direction are given as steer characteristics by the differential limiting torque control with a high control gain, and vehicle stability is ensured. In other words, during high lateral acceleration turning in the acceleration slip state, stability is obtained on the differential limiting torque control side, and acceleration is obtained on the throttle control side. Will be achieved.

For example, during low lateral acceleration turning, throttle control and differential limiting torque control are performed by increasing the throttle control gain relative to the differential limiting torque control gain. Therefore, a strong understeer is prevented by the differential limiting torque control in which the control gain is relatively low, and the operability is ensured.

The effect will be described.

In an integrated control system of engine output and differential limiting torque applied to a vehicle equipped with both a throttle control system and a differential limiting torque control system, when an acceleration slip occurs and the lateral acceleration is high, a relative control is performed. Since the differential limiting torque control gain is increased and the throttle control gain is relatively increased in the low lateral acceleration state, the acceleration performance during high lateral acceleration turning in the acceleration slip state is ensured, and the low It is possible to achieve both stability and stability at the time of lateral acceleration turning.

Although the embodiment has been described with reference to the drawings, the specific configuration is not limited to this embodiment.

For example, in the embodiment, the example of the output control of the internal combustion engine by the throttle control has been described. However, other than the throttle control, an ignition cut, a cylinder cut, an ignition timing retard, or the like may be used.

As the differential limiting torque control, in the embodiment, an example of the differential limiting torque control based on the lateral acceleration and the turning radius disclosed in Japanese Patent Application Laid-Open No. 1-106737 has been described. The specific control content is not limited to the embodiment as long as the differential limiting torque related to the control is controlled.

[0037]

As described above, in the present invention, the output of the internal combustion engine and the differential limiting torque applied to a vehicle equipped with both the internal combustion engine output control system and the differential limiting torque control system are described. The general control system
Internal combustion engine output control gain and differential limited torque control
When the control gain is set to 1 and acceleration slip occurs,
Without changing the sum of the two control gains, the differential limiting torque control gain is increased relative to the internal combustion engine output control gain in the high lateral acceleration state, and the differential limiting torque control gain is increased in the low lateral acceleration state. The gain adjustment control means for increasing the internal combustion engine output control gain is provided to ensure the acceleration performance when turning at high lateral acceleration in the acceleration slip state and the stability during turning at low lateral acceleration in the acceleration slip state. The effect that both can be achieved is obtained.

[Brief description of the drawings]

FIG. 1 is a claim correspondence diagram showing a total control device for an internal combustion engine output and a differential limiting torque according to the present invention.

FIG. 2 is an overall system diagram of a rear-wheel drive vehicle to which the integrated control device for internal combustion engine output and differential limiting torque according to the embodiment is applied;

FIG. 3 is a flowchart showing a flow of a total control operation of a throttle control and a differential limiting torque control performed by a general control unit of the embodiment device.

[Explanation of symbols]

 a acceleration slip state detection means b internal combustion engine output control means c lateral acceleration detection means d differential limiting torque control means e gain adjustment control means

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B60K 41/00-41/28 B60K 17/348 B60K 23/00-23/08 B60T 7/12-7 / 22 B60T 8/32-8/96

Claims (1)

(57) [Claims] 1. An acceleration slip state detecting means for detecting an acceleration slip state of a driving wheel; an internal combustion engine output control means for controlling to reduce an internal combustion engine output in accordance with the acceleration slip state; and a lateral detecting means for detecting a lateral acceleration applied to a vehicle. Acceleration detecting means; differential limiting torque control means for controlling the differential limiting torque of the left and right driving wheels by including the lateral acceleration in the input information ; internal combustion engine output control gain and differential limiting torque in a normal control state;
Acceleration slip occurred when the luk control gain was set to 1 for each.
At this time, without changing the sum of the two control gains, the differential limiting torque control gain is increased relative to the internal combustion engine output control gain in the high lateral acceleration state, and the differential limiting torque control gain is increased in the low lateral acceleration state. And a gain adjustment control means for relatively increasing the output control gain of the internal combustion engine, and a total control device for the output of the internal combustion engine and the differential limiting torque.