Hybrid tire inflation monitor

• US 20040207518A1
• Filed: 04/16/2003
• Published: 10/21/2004
• Est. Priority Date: 04/16/2003
• Status: Active Grant

• Current Assignee: BWI Company Limited SA (Shougang Corporation)
• Original Assignee: Delphi Technologies, Inc. (Aptiv PLC)
• Inventors: Littlejohn, Deron C., Fulmer, Bryan T., Tamimi, Mohammad A.
• Granted Patent: US 6,956,471 B2
• Time in Patent Office: Days
• US Class Current: 340/443
• CPC Class Codes: B60C 23/0408 transmitting the signals by non-mechanical means from the wheel or tyre to a vehicle body mounted receiver
• CPC Class Codes: B60C 23/061 by monitoring wheel speed measuring distance traversed on the ground by vehicles G01C22/00

Abstract

The present invention provides a method, a computer usable medium including a program, and a system for monitoring inflation in a plurality of vehicle tires. The method and computer usable medium include the steps of determining a direct pressure in at least one primary tire and determining a rolling radius for the primary tire and at least one secondary tire. A pressure difference is determined based on the determined rolling radius for the primary and secondary tires. The determined pressure difference is adjusted based on the determined direct pressure of the primary tire. The determined pressure difference is compared to at least one threshold value. The system includes means for achieving the method steps of the invention.

Claims

1. A method of monitoring inflation in a plurality of vehicle tires, the method comprising:

determining a direct pressure in at least one primary tire;

determining a rolling radius for the primary tire and at least one secondary tire;

determining a pressure difference based on the determined rolling radius for the primary and secondary tires;

adjusting the determined pressure difference based on the determined direct pressure of the primary tire; and

comparing the determined pressure difference to at least one threshold value.

2. The method of claim 1 wherein the rolling radius is determined based on at least one offset value.

3. The method of claim 1 wherein the pressure difference is determined for a plurality of tire pairs.

4. The method of claim 1 wherein the threshold value is determined based on at least one adjustment factor.

5. The method of claim 1 wherein the threshold value is predetermined.

6. The method of claim 1 further comprising filtering results of the comparison of the pressure difference to the threshold value.

7. The method of claim 1 further comprising indicating a tire inflation status based on the comparison of the pressure difference to the threshold value.

8. The method of claim 7 wherein the tire inflation status comprises an indication selected from a group consisting of a low tire pressure, a flat tire pressure, a high tire pressure, and a normal tire pressure.

9. A computer usable medium including a program for monitoring inflation in a plurality of vehicle tires, the computer usable medium comprising:

computer readable program code for determining a direct pressure from a signal in at least one primary tire;

computer readable program code for determining a rolling radius for the primary tire and at least one secondary tire;

computer readable program code for determining a pressure difference based on the determined rolling radius for the primary and secondary tires;

computer readable program code for adjusting the determined pressure difference based on the determined direct pressure of the primary tire; and

computer readable program code for comparing the determined pressure difference to at least one threshold value.

10. The computer usable medium of claim 9 wherein the rolling radius is determined based on at least one offset value.

11. The computer usable medium of claim 9 wherein the pressure difference is determined for a plurality of tire pairs.

12. The computer usable medium of claim 9 wherein the threshold value is determined based on at least one adjustment factor.

13. The computer usable medium of claim 9 wherein the threshold value is predetermined.

14. The computer usable medium of claim 9 further comprising computer readable program code for filtering results of the comparison of the pressure difference to the threshold value.

15. The computer usable medium of claim 9 further comprising computer readable program code for indicating a tire inflation status based on the comparison of the pressure difference to the threshold value.

16. The computer usable medium of claim 15 wherein the tire inflation status comprises an indication selected from a group consisting of a low tire pressure, a flat tire pressure, a high tire pressure, and a normal tire pressure.

17. A system for monitoring inflation in a plurality of vehicle tires, the system comprising:

means for determining a direct pressure in at least one primary tire;

means for determining a rolling radius for the primary tire and at least one secondary tire; and

means for determining a pressure difference based on the determined rolling radius for the primary and secondary tires, wherein the determined pressure difference is adjusted based on the determined direct pressure of the primary tire, and the determined pressure difference is compared to at least one threshold value.

18. The system of claim 17 further comprising means for filtering the comparison of the determined pressure difference to the threshold value.

19. The system of claim 17 further comprising means for indicating a tire pressure status based on the comparison of the pressure difference to the determined threshold value.

20. The system of claim 19 wherein the tire pressure status comprises an indication selected from a group consisting of a low tire pressure, a flat tire pressure, a high tire pressure, and a normal tire pressure.