Tire risk judging device of wheel assembly for vehicle

• US 7,839,274 B2
• Filed: 05/15/2007
• Issued: 11/23/2010
• Est. Priority Date: 05/31/2006
• Status: Expired due to Fees

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Isono, Hiroshi
• Primary Examiner(s): Wu; Daniel
• Assistant Examiner(s): GIRMA, FEKADESELASS
• Application Number:
  US11/915,036
• Publication Number:
  US 20100001852A1
• Time in Patent Office: 1,288 Days
• Field of Search: None
• US Class Current: 340/442
• CPC Class Codes: B60C 23/127 the pumps being mounted on the hubs
• CPC Class Codes: B60C 23/137 comprising cam driven pistons

Abstract

A tire risk judging device of a wheel assembly for a vehicle includes a pressure sensor detecting air pressure of a tire air chamber, an air pressure-generating device that can supply pressurized air to the tire air chamber, an electronic control unit, and an instrument panel display unit. The electronic control unit computes a supply airflow rate supplied from the air pressure-generating device to the tire air chamber between the present location and a specified location, computes a leakage airflow rate leaked from the tire air chamber between the present location and the specified location, computes air pressure in the specified location of the tire air chamber based on air pressure in the present location of the tire air chamber, the supply airflow rate, and the leakage airflow rate, and judges tire risk in the specified location based on the air pressure in the specified location of the tire air chamber.

Claims

1. A tire risk judging device of a wheel assembly for a vehicle, comprising:

a pressure sensor that detects air pressure of a tire air chamber of the wheel assembly of the vehicle;

an air pressure-generating device that supplies pressurized air to the tire air chamber;

supply airflow rate computation means for computing a supply airflow rate supplied from the air pressure-generating device to the tire air chamber when the vehicle drives from a present vehicle location to a specified vehicle location on a particular path;

leakage airflow rate computation means for computing a leakage airflow rate leaked from the tire air chamber when the vehicle drives from the present vehicle location to the specified vehicle location on the particular path;

tire air pressure computation means for computing air pressure of the tire air chamber when the vehicle is located in the specified vehicle location based on air pressure of the tire air chamber when the vehicle is located in the present vehicle location detected by the pressure sensor, the supply airflow rate computed by the supply airflow rate computation means, and the leakage airflow rate computed by the leakage airflow rate computation means; and

specified location tire risk judgment means for judging tire risk in the specified vehicle location based on the air pressure of the tire air chamber when the vehicle is located in the specified vehicle location computed by the tire air pressure computation means.

2. The tire risk judging device of a wheel assembly for a vehicle according to claim 1, further comprising:

present location tire risk judgment means for judging tire risk in the present vehicle location based on the air pressure of the tire air chamber when the vehicle is located in the present vehicle location detected by the pressure sensor.

3. The tire risk judging device of a wheel assembly for a vehicle according to claim 1, further comprising:

specified location tire risk notification means for notifying an occupant of tire risk in the specified vehicle location judged by the specified location tire risk judgment means.

4. The tire risk judging device of a wheel assembly for a vehicle according to claim 2, further comprising:

present location tire risk notification means for notifying an occupant of tire risk in the present vehicle location judged by the present location tire risk judgment means.

5. The tire risk judging device of a wheel assembly for a vehicle according to claim 2, further comprising:

present location tire risk notification means for notifying the occupant of tire risk in the present vehicle location judged by the present location tire risk judgment means; and

specified location tire risk notification means for notifying the occupant of tire risk in the specified vehicle location judged by the specified location tire risk judgment means.

6. The tire risk judging device of a wheel assembly for a vehicle according to claim 1, wherein the air pressure-generating device is driven by rotation of the wheel assembly.

7. The tire risk judging device of a wheel assembly for a vehicle according to claim 1, further comprising:

tire load computation means for computing a load applied on the tire of the wheel assembly when the vehicle drives from the present vehicle location to the specified vehicle location on the particular path; and

tire risk correction means for correcting the tire risk judged by the specified location tire risk judgment means according to the tire load computed by the tire load computation means.

8. The tire risk judging device of a wheel assembly for a vehicle according to claim 1, wherein the particular path is one path selected from plural predetermined paths.

9. The tire risk judging device of a wheel assembly for a vehicle according to claim 8, further comprising:

different path supply airflow rate computation means for computing a supply airflow rate supplied from the air pressure-generating device to the tire air chamber when the vehicle drives from the present vehicle location to the specified vehicle location on a path different from the particular path;

different path leakage airflow rate computation means for computing a leakage airflow rate leaked from the tire air chamber when the vehicle drives from the present vehicle location to the specified vehicle location on the path different from the particular path;

different path tire air pressure computation means for computing air pressure of the tire air chamber when the vehicle is in the specified vehicle location based on air pressure of the tire air chamber when the vehicle is the present vehicle location detected by the pressure sensor, the supply airflow rate computed by the different path supply airflow rate computation means, and the leakage airflow rate computed by the different path leakage airflow rate computation means; and

recommended path notification means for selecting a path having the lowest tire risk degree in the specified vehicle location based on the air pressures computed by the different path tire air pressure computation means and the tire air pressure computation means and for notifying the occupant of the path having the lowest tire risk degree in the specified vehicle location.

10. The tire risk judging device of a wheel assembly for a vehicle according to claim 1, further comprising:

an on-board navigation device that computes a plurality of paths between the present vehicle position and the specified vehicle position and computes a plurality of distances that correspond to each of the plurality of paths.

11. The tire risk judging device of a wheel assembly for a vehicle according to claim 10, further comprising:

comparison path supply airflow rate computation means for computing a supply airflow rate supplied from the air pressure-generating device to the tire air chamber when the vehicle drives from the present vehicle location to the specified vehicle location on each of the plurality of paths;

comparison path leakage airflow rate computation means for computing a leakage airflow rate leaked from the tire air chamber when the vehicle drives from the present vehicle location to the specified vehicle location on each of the plurality of paths;

comparison path tire air pressure computation means for computing air pressures of the tire air chamber when the vehicle is in the specified vehicle location based on air pressure of the tire air chamber when the vehicle is the present vehicle location detected by the pressure sensor, the supply airflow rates computed by the comparison path supply airflow rate computation means, and the leakage airflow rates computed by the different path leakage airflow rate computation means; and

recommended path notification means for selecting a recommended path of the plurality of paths having the lowest tire risk degree in the specified vehicle location based on the air pressures computed by the comparison path tire air pressure computation means and the comparison tire air pressure computation means,

wherein the recommended path notification means notifies the occupant of the recommended path.

12. A tire risk judging device of a wheel assembly for a vehicle, comprising:

a pressure sensor that detects air pressure of a tire air chamber of the wheel assembly of the vehicle;

an air pressure-generating device that supplies pressurized air to the tire air chamber;

a supply airflow rate computation device that computes a supply airflow rate supplied from the air pressure-generating device to the tire air chamber when the vehicle drives from a present vehicle location to a specified vehicle location on a particular path;

a leakage airflow rate computation device that computes a leakage airflow rate leaked from the tire air chamber when the vehicle drives from the present vehicle location to the specified vehicle location on the particular path;

a tire air pressure computation device that computes air pressure of the tire air chamber when the vehicle is located in the specified vehicle location based on air pressure of the tire air chamber when the vehicle is located in the present vehicle location detected by the pressure sensor, the supply airflow rate computed by the supply airflow rate computation device, and the leakage airflow rate computed by the leakage airflow rate computation device; and

a specified location tire risk judgment device that judges tire risk in the specified vehicle location based on the air pressure of the tire air chamber when the vehicle is located in the specified vehicle location computed by the tire air pressure computation means.

13. The tire risk judging device of a wheel assembly for a vehicle according to claim 12, further comprising:

an on-board navigation device that computes a plurality of paths between the present vehicle position and the specified vehicle position and computes a plurality of distances that correspond to each of the plurality of paths.

14. The tire risk judging device of a wheel assembly for a vehicle according to claim 13, further comprising:

a comparison path supply airflow rate computation device that computes a supply airflow rate supplied from the air pressure-generating device to the tire air chamber when the vehicle drives from the present vehicle location to the specified vehicle location on each of the plurality of paths;

a comparison path leakage airflow rate computation device that computes a leakage airflow rate leaked from the tire air chamber when the vehicle drives from the present vehicle location to the specified vehicle location on each of the plurality of paths;

a comparison path tire air pressure computation device that computes air pressures of the tire air chamber when the vehicle is in the specified vehicle location based on air pressure of the tire air chamber when the vehicle is the present vehicle location detected by the pressure sensor, the supply airflow rates computed by the comparison path supply airflow rate computation device, and the leakage airflow rates computed by the different path leakage airflow rate computation device; and

a recommended path notification device that selects a recommended path of the plurality of paths that has the lowest tire risk degree in the specified vehicle location based on the air pressures computed by the comparison path tire air pressure computation device and the comparison tire air pressure computation device,

wherein the recommended path notification device notifies the occupant of the recommended path.