CONTROL DEVICE FOR CONTROLLING DRIVE FORCE THAT OPERATES ON VEHICLE

• US 20120253622A1
• Filed: 03/30/2011
• Published: 10/04/2012
• Est. Priority Date: 03/30/2011
• Status: Active Grant

• Current Assignee: Autoliv Nissin Brake Systems Japan Co., Ltd. (Autoliv Incorporated)
• Original Assignee: Nissin Kogyo Company Limited (Hitachi, Ltd.)
• Inventors: Handa, Toshiyuki
• Granted Patent: US 8,725,377 B2
• Time in Patent Office: Days
• US Class Current: 701/69
• CPC Class Codes: B60K 17/344 having a transfer gear
• CPC Class Codes: B60K 2023/0883 manually actuated
• CPC Class Codes: B60K 23/0808 for varying torque distribution between driven axles, e.g. by transfer clutch
• CPC Class Codes: B60W 2510/0638 Engine speed
• CPC Class Codes: B60W 2510/0671 Engine manifold pressure
• CPC Class Codes: B60W 2520/105 Longitudinal acceleration
• CPC Class Codes: B60W 2520/125 Lateral acceleration
• CPC Class Codes: B60W 2540/10 Accelerator pedal position
• CPC Class Codes: B60W 2540/16 Ratio selector position
• CPC Class Codes: B60W 2540/18 Steering angle
• CPC Class Codes: B60W 2720/403 between front and rear axle

Abstract

A drive force-limiting device for limiting a drive force that acts on a drive wheel of a vehicle includes an acceleration correction unit for correcting a first acceleration of the vehicle and obtaining a corrected second acceleration, a first calculation unit for calculating a first speed of the vehicle on the basis of a wheel speed of the drive wheel and the first acceleration, a second calculation unit for calculating a second speed of the vehicle on the basis of the wheel speed and the second acceleration, a request unit for requesting a limiting drive force for limiting the drive force in a case that a difference between the first speed and the second speed is equal to or greater than a first threshold value, and an estimation unit in which the second speed is used as an estimated speed of the vehicle. The request unit requests the limiting drive force, whereby, when the wheel speed is less than a second threshold value, the estimation unit resets the second speed using the first speed and obtains the estimated speed.

Claims

1. A drive force-limiting device for limiting a drive force that acts on a drive wheel of a vehicle, the drive force-limiting device comprising:

an acceleration correction unit for correcting a first acceleration of the vehicle and obtaining a corrected first acceleration as a second acceleration;

a first calculation unit for calculating a first speed of the vehicle on the basis of a wheel speed of the drive wheel and the first acceleration;

a second calculation unit for calculating a second speed of the vehicle on the basis of the wheel speed and the second acceleration;

a request unit for requesting a limiting drive force for limiting the drive force in a case that a difference between the first speed and the second speed is equal to or greater than a first threshold value; and

an estimation unit in which the second speed is used as an estimated speed of the vehicle, wherein

the request unit requests the limiting drive force, whereby, when the wheel speed is less than a second threshold value, the estimation unit resets the second speed using the first speed and obtains the estimated speed.

2. The drive force-limiting device according to claim 1, wherein

The estimation unit uses, as the estimated speed, a value obtained by subtracting, from the second speed calculated by the second calculation unit, the difference between the second speed and the first speed when the wheel speed is less than the second threshold value.

3. The drive force-limiting device according to claim 1, wherein

the limiting drive force is a drive force that does not affect the first acceleration.

4. The drive force-limiting device according to claim 1, wherein

the limiting drive force is a drive force that can keep the first acceleration in a state in which the drive wheel does not slip.

5. The drive force-limiting device according to claim 1, wherein

the estimation unit continues to use the second speed as the estimated speed in a case that the wheel speed is not less than the second threshold, even when a predetermined time has elapsed from the time at which the request unit requested the limiting drive force.

6. The drive force-limiting device according to claim 1, wherein

the request unit sends the limiting drive force to a drive force control device for controlling a front wheel drive force and a rear wheel drive force of the vehicle;

the drive wheel is an auxiliary drive wheel;

the drive force is an auxiliary drive wheel drive force that acts on the auxiliary drive wheel;

the limiting drive force limits the drive force of the auxiliary drive wheel; and

the auxiliary drive wheel drive force is one of the drive force of the front wheel or the drive force of the rear wheel.

7. The drive force-limiting device according to claim 1, wherein

the request unit sends the limiting drive force to motor control device for controlling a motor of the vehicle;

and

the limiting drive force limits motor drive force.

8. The drive force-limiting device according to claim 1, wherein

the second threshold value is based on at least one of the first speed and the second speed.

9. The drive force-limiting device according to claim 1, wherein

the second threshold value is based on a ratio with respect to the difference between the first speed and the second speed.

10. A control device comprising:

the drive force-limiting device of claim 1; and

a drive force control device for controlling the drive force, wherein

the request unit sends the limiting drive force to the drive force control device.

11. A vehicle behavior control device provided with the drive force-limiting device of claim 1.