Driving force controlling apparatus for vehicle

• US 5,576,960 A
• Filed: 04/21/1995
• Issued: 11/19/1996
• Est. Priority Date: 10/25/1991
• Status: Expired due to Fees

• Current Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company)
• Original Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company)
• Inventors: Maeda, Shinichi
• Primary Examiner(s): Teska, Kevin J.
• Assistant Examiner(s): LOUIS JACQUES, JACQUES H
• Application Number:
  US08/426,945
• Time in Patent Office: 578 Days
• Field of Search: 364/424.01, 364/424.03, 364/426.01, 364/426.02, 364/426.03, 364/565, 364/552, 303/183, 303/158, 303/168, 303/191, 303/173, 303/141, 303/127, 303/171, 303/139, 303/169, 303/148, 180/197, 180/233, 180/249, 324/161, 324/422, 324/166, 324/170
• US Class Current: 701/70
• 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 8/1706 for single-track vehicles, e.g. motorcycles
• 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 2050/021 Means for detecting failure or malfunction
• CPC Class Codes: G01D 1/00 Measuring arrangements giving results other than momentary value of variable, of general application G01D3/00 takes precedence; in tariff metering apparatus G01D4/00; transducers not specially adapted for a specific variable G01D5/00
• CPC Class Codes: G01P 21/02 of speedometers

Abstract

To prevent a great variation of a detected wheel velocity for a period of time after a front wheel sensor or a rear wheel sensor for detection of a wheel velocity actually fails until a microcomputer detects the failure, it is determined whether or not an output pulse period of a front wheel sensor is equal to or shorter than a predetermined period. When the output pulse period exceeds the predetermined period, it is determined that there is the possibility that the front wheel sensor may be in failure, thus a front wheel velocity for a predetermined number of control cycles before (a front wheel velocity before the failure) is adopted as a front wheel velocity of the present control cycle. Also, a rear wheel velocity is calculated in a similar manner. For a time after a failure actually occurs until the failure is detected by a microcomputer, driving force control is not started even if other starting conditions for driving force control are satisfied.

Claims

1. An apparatus to prevent a great variation of a detected wheel velocity for a period of time after a front wheel sensor actually fails until a microcomputer detects the failure, comprising:

determining means for determining whether an output pulse period of the front wheel sensor is equal to or shorter than a predetermined period;

failure means for determining a failure when the output pulse period of the front wheel sensor exceeds the predetermined period; and

velocity means for setting a front wheel velocity to a velocity equal to a velocity calculated a predetermined number of control cycles before the failure.

2. The apparatus as claimed in claim 1 wherein said predetermined number is nine.

3. An apparatus to prevent a great variation of a detected wheel velocity for a period of time after a rear wheel sensor actually fails until a microcomputer detects the failure, comprising:

determining means for determining whether an output pulse period of the rear wheel sensor is equal to or shorter than a predetermined period;

failure means for determining a failure when the output pulse period of the rear wheel sensor exceeds the predetermined period; and

velocity means for setting a rear wheel velocity to a velocity equal to a velocity calculated a predetermined number of control cycles before the failure.

4. The apparatus as claimed in claim 3 wherein said determining means determines whether an output pulse period of a front wheel sensor is equal to or shorter than the predetermined period;

said failure means determining a failure when the outputted pulse period of the front wheel sensor exceeds the predetermined period; and

said velocity means setting a front wheel velocity to a velocity equal to a velocity calculated a predetermined number of control cycles before failure.

5. The apparatus as claimed in claim 4 wherein said predetermined number is nine.

6. The apparatus as claimed in claim 3 wherein said predetermined number is nine.

7. A method for preventing a great variation of a detected wheel velocity for a period of time after a front wheel sensor actually fails until a microcomputer detects the failure, comprising the steps of:

(a) determining whether an output pulse period of the front wheel sensor is equal to or shorter than a predetermined period;

(b) determining a failure when the output pulse period of the front wheel sensor exceeds the predetermined period; and

(c) setting a front wheel velocity to a velocity equal to a velocity calculated a predetermined number of control cycles before the failure.

8. The method as claimed in claim 7 wherein said predetermined number is nine.

10. The method as claimed in claim 8, further comprising the steps of:

(d) determining whether an output pulse period of a front wheel sensor is equal to or shorter than the predetermined period;

(e) determining a failure when the output pulse period of the front wheel sensor exceeds the predetermined period; and

(f) setting a front wheel velocity to a velocity equal to a velocity calculated a predetermined number of control cycles before failure.

11. The method as claimed in claim 10 wherein said predetermined number is nine.

9. A method for preventing a great variation of a detected wheel velocity for a period of time after a rear wheel sensor actually fails until a microcomputer detects the failure, comprising the steps of:

(a) determining whether an output pulse period of the rear wheel sensor is equal to or shorter than a predetermined period;

(b) determining a failure when the output pulse period of the rear wheel sensor exceeds the predetermined period; and

(c) setting a rear wheel velocity to a velocity equal to a velocity calculated a predetermined number of control cycles before the failure.

12. The method as claimed in claim 9 wherein said predetermined number is nine.

13. A driving force controlling apparatus for a vehicle, comprising:

wheel velocity calculating means for calculating a velocity of a driven wheel and a velocity of a driving wheel of the vehicle;

average wheel velocity calculating means for calculating an average driven wheel velocity and an average driving wheel velocity from the driven wheel velocity and the driving wheel velocity;

slip level detecting means for detecting a slip level of the vehicle from the average driven wheel velocity and the average driving wheel velocity;

retard amount setting means for setting a retard amount of an ignition time in response to the slip level;

driving force controlling ignition time setting means for setting an ignition time for driving force control using said retard amount;

period comparing means for determining whether a period of pulses outputted from at least one of the wheel velocity detecting sensors is equal to or lower than a predetermined period; and

velocity means for supplying, when the period of the pulses is not equal to or lower than the predetermined period, a wheel velocity for a present control cycle which corresponds to a velocity calculated a predetermined number of control cycles before.

14. The apparatus as claimed in claim 13 wherein said predetermined number is nine.

15. A method for determining a velocity value for a driving force controlling apparatus for a vehicle, comprising the steps of:

(a) calculating a velocity of a driven wheel and a velocity of a driving wheel of the vehicle;

(b) calculating an average driven wheel velocity and an average driving wheel velocity from the driven wheel velocity and the driving wheel velocity;

(c) detecting a slip level of the vehicle from the average driven wheel velocity and the average driving wheel velocity;

(d) setting a retard amount of an ignition time in response to the slip level;

(e) setting an ignition time for driving force control using the retard amount;

(f) determining whether a period of pulses outputted from at least one of the wheel velocity detecting sensors is equal to or lower than a predetermined period; and

(g) setting, when the period of the pulses is not equal to or lower than the predetermined period, a wheel velocity for a present control cycle to a velocity calculated a predetermined number of control cycles before.

16. The method as claimed in claim 15 wherein said predetermined number is nine.

17. A driving force controlling apparatus for a vehicle, comprising:

period comparing means for determining whether a period of pulses outputted from at least one of the wheel velocity detecting sensors is equal to or lower than a predetermined period; and

velocity means for supplying, when the period of the pulses is not equal to or lower than the predetermined period, a wheel velocity for a present control cycle which corresponds to a velocity calculated a predetermined number of control cycles before.

18. The apparatus as claimed in claim 17 wherein said predetermined number is nine.

19. A method for determining a velocity value for a driving force controlling apparatus for a vehicle, comprising the steps of:

(f) determining whether a period of pulses outputted from at least one of the wheel velocity detecting sensors is equal to or lower than a predetermined period; and

(g) setting, when the period of the pulses is not equal to or lower than the predetermined period, a wheel velocity for a present control cycle to a velocity calculated a predetermined number of control cycles before.

20. The method as claimed in claim 19 wherein said predetermined number is nine.