Traction control device

• US 20050065702A1
• Filed: 09/23/2004
• Published: 03/24/2005
• Est. Priority Date: 09/24/2003
• Status: Active Grant

• Current Assignee: Advics Company Limited (Aisin Corp.)
• Original Assignee: Advics Company Limited (Aisin Corp.)
• Inventors: Inoue, Yasumi, Tsuruhara, Ryuzo
• Granted Patent: US 7,472,012 B2
• Time in Patent Office: Days
• US Class Current: 701/82
• CPC Class Codes: B60K 28/16 responsive to, or preventing, skidding of wheels brake control systems for vehicle drive stability B60T8/1755; arrangements responsive to a speed condition for adjusting wheel braking force B60T8/32; control of vehicle driving stability otherwise than by controlling the propulsion unit only B60W30/02; preventing wheel slippage by reducing power in rail vehicles B61C15/00
• CPC Class Codes: B60T 8/175 Brake regulation specially adapted to prevent excessive wheel spin during vehicle acceleration, e.g. for traction control safety devices for propulsion unit control responsive to, or preventing, skidding of wheels B60K28/16
• CPC Class Codes: B60W 2520/263 Slip values between front and rear axle
• CPC Class Codes: B60W 2520/28 Wheel speed

Abstract

A newly obtained wheel speed of a drive wheel is not used in a calculation for acceleration slip when a vehicle is stopped, for example, when the wheel speed of a rolling wheel is zero and an engine speed is high. A wheel speed calculated before a previous wheel speed is, for example, set as a current wheel speed. In this manner, even if the wheel speed of a driving wheel is due to the effect of racing noise, it is possible to limit erroneous determinations that indicate acceleration slip is being generated, based upon such a wheel speed. In addition, unnecessary execution of a traction control can also be curbed.

Claims

1. A traction control device comprising:

a wheel speed detection mechanism for detecting a wheel speed of a drive wheel in a vehicle;

an acceleration slip detection mechanism for detecting acceleration slip of the drive wheel based upon a wheel speed detected by the wheel speed detection mechanism;

a driving force reduction mechanism for reducing a driving force transmitted to the drive wheel such that the acceleration slip is suppressed when the acceleration slip is detected by the acceleration slip detection mechanism; and

an engine speed detection mechanism for detecting a speed of an engine mounted in the vehicle, wherein

reduction of the driving force by the driving force reduction mechanism is stopped when the engine speed detected by the engine speed detection mechanism exceeds a predetermined speed.

2. The traction control device according to claim 1 further comprising:

a vehicle stop determination mechanism for determining whether the vehicle is stopped, wherein

the acceleration slip detection mechanism stops detection of the acceleration slip based upon the wheel speed detected by the wheel speed detection mechanism when it is determined by the vehicle stop determination mechanism that the vehicle is stopped.

3. The traction control device according to claim 1, wherein the wheel speed is calculated every predetermined control cycle in the wheel speed detection mechanism;

and in cases where the calculated wheel speed increases and subsequently decreases within a first set of control cycles, the driving force reduction mechanism stops reducing the driving force.

4. The traction control device according to claim 2, wherein the wheel speed is calculated every predetermined control cycle in the wheel speed detection mechanism;

and in cases where the calculated wheel speed increases and subsequently decreases within a first set of control cycles, the driving force reduction mechanism stops reducing the driving force.

5. The traction control device according to claim 1, wherein the wheel speed is calculated every predetermined control cycle in the wheel speed detection mechanism;

and in cases where the calculated wheel speed continues to show an increasing tendency for a second set of control cycles or longer, the driving force reduction mechanism cancels the stop on reduction of driving force and starts reducing the driving force.

6. The traction control device according to claim 2, wherein the wheel speed is calculated every predetermined control cycle in the wheel speed detection mechanism;

and in cases where the calculated wheel speed continues to show an increasing tendency for a second set of control cycles or longer, the driving force reduction mechanism cancels the stop on reduction of driving force and starts reducing the driving force.

7. The traction control device according to claim 3, wherein the wheel speed is calculated every predetermined control cycle in the wheel speed detection mechanism;

and in cases where the calculated wheel speed continues to show an increasing tendency for a second set of control cycles or longer, the driving force reduction mechanism cancels the stop on reduction of driving force and starts reducing the driving force.

8. The traction control device according to claim 4, wherein the wheel speed is calculated every predetermined control cycle in the wheel speed detection mechanism;

and in cases where the calculated wheel speed continues to show an increasing tendency for a second set of control cycles or longer, the driving force reduction mechanism cancels the stop on reduction of driving force and starts reducing the driving force.

9. The traction control device according to claim 1, wherein the wheel speed is calculated every predetermined control cycle in the wheel speed detection mechanism;

and in cases where the calculated wheel speed continues to increase and decrease, the driving force reduction mechanism stops reducing the driving force.

10. The traction control device according to claim 2, wherein the wheel speed is calculated every predetermined control cycle in the wheel speed detection mechanism;

and in cases where the calculated wheel speed continues to increase and decrease, the driving force reduction mechanism stops reducing the driving force.

11. The traction control device according to claim 3, wherein among the wheel speeds calculated every predetermined control cycle in the wheel speed detection mechanism, in cases where an absolute value of a difference between a current wheel speed newly calculated and a previous wheel speed previously calculated is equal to or greater than a predetermined value, and an absolute value of a difference between the previous wheel speed and a wheel speed before the previous wheel speed, which is calculated prior to the previous wheel speed, is equal to or greater than the predetermined value, the wheel speed before the previous wheel speed is set as a new wheel speed;

thus stopping reduction of the driving force by the driving force reduction mechanism.

12. The traction control device according to claim 5, wherein among the wheel speeds calculated every predetermined control cycle in the wheel speed detection mechanism, in cases where an absolute value of a difference between a current wheel speed newly calculated and a previous wheel speed previously calculated is equal to or greater than a predetermined value, and an absolute value of a difference between the previous wheel speed and a wheel speed before the previous wheel speed, which is calculated prior to the previous wheel speed, is equal to or greater than the predetermined value, the wheel speed before the previous wheel speed is set as a new wheel speed;

thus stopping reduction of the driving force by the driving force reduction mechanism.

13. The traction control device according to claim 9, wherein among the wheel speeds calculated every predetermined control cycle in the wheel speed detection mechanism, in cases where an absolute value of a difference between a current wheel speed newly calculated and a previous wheel speed previously calculated is equal to or greater than a predetermined value, and an absolute value of a difference between the previous wheel speed and a wheel speed before the previous wheel speed, which is calculated prior to the previous wheel speed, is equal to or greater than the predetermined value, the wheel speed before the previous wheel speed is set as a new wheel speed;

thus stopping reduction of the driving force by the driving force reduction mechanism.

14. The traction control device according to claim 11, wherein a value smaller than the current wheel speed is set as the new wheel speed in the wheel speed detection mechanism, in one of a case where the absolute value of the difference between the current wheel speed and the previous wheel speed is equal to or greater than the predetermined value, and a case where the absolute value of the difference between the previous wheel speed and the wheel speed before the previous wheel speed is equal to or greater than the predetermined value;

thus stopping reduction of the driving force by the driving force reduction mechanism.

15. The traction control device according to claim 12, wherein a value smaller than the current wheel speed is set as the new wheel speed in the wheel speed detection mechanism, in one of a case where the absolute value of the difference between the current wheel speed and the previous wheel speed is equal to or greater than the predetermined value, and a case where the absolute value of the difference between the previous wheel speed and the wheel speed before the previous wheel speed is equal to or greater than the predetermined value;

thus stopping reduction of the driving force by the driving force reduction mechanism.

16. The traction control device according to claim 13, wherein a value smaller than the current wheel speed is set as the new wheel speed in the wheel speed detection mechanism, in one of a case where the absolute value of the difference between the current wheel speed and the previous wheel speed is equal to or greater than the predetermined value, and a case where the absolute value of the difference between the previous wheel speed and the wheel speed before the previous wheel speed is equal to or greater than the predetermined value;

thus stopping reduction of the driving force by the driving force reduction mechanism.

17. The traction control device according to claim 11, wherein the current wheel speed is set as the new wheel speed in the wheel speed detection mechanism, in cases where the absolute value of the difference between the current wheel speed and the previous wheel speed is smaller than the predetermined value, and the absolute value of the difference between the previous wheel speed and the wheel speed before the previous wheel speed is smaller than the predetermined value.

18. The traction control device according to claim 12, wherein the current wheel speed is set as the new wheel speed in the wheel speed detection mechanism, in cases where the absolute value of the difference between the current wheel speed and the previous wheel speed is smaller than the predetermined value, and the absolute value of the difference between the previous wheel speed and the wheel speed before the previous wheel speed is smaller than the predetermined value.

19. The traction control device according to claim 13, wherein the current wheel speed is set as the new wheel speed in the wheel speed detection mechanism, in cases where the absolute value of the difference between the current wheel speed and the previous wheel speed is smaller than the predetermined value, and the absolute value of the difference between the previous wheel speed and the wheel speed before the previous wheel speed is smaller than the predetermined value.

20. The traction control device according to claim 14, wherein the current wheel speed is set as the new wheel speed in the wheel speed detection mechanism, in cases where the absolute value of the difference between the current wheel speed and the previous wheel speed is smaller than the predetermined value, and the absolute value of the difference between the previous wheel speed and the wheel speed before the previous wheel speed is smaller than the predetermined value.

21. The traction control device according to claim 15, wherein the current wheel speed is set as the new wheel speed in the wheel speed detection mechanism, in cases where the absolute value of the difference between the current wheel speed and the previous wheel speed is smaller than the predetermined value, and the absolute value of the difference between the previous wheel speed and the wheel speed before the previous wheel speed is smaller than the predetermined value.

22. The traction control device according to claim 16, wherein the current wheel speed is set as the new wheel speed in the wheel speed detection mechanism, in cases where the absolute value of the difference between the current wheel speed and the previous wheel speed is smaller than the predetermined value, and the absolute value of the difference between the previous wheel speed and the wheel speed before the previous wheel speed is smaller than the predetermined value.