Method and apparatus for detecting decrease in tire air-pressure, and program for judging decompression of tire

• US 20040249528A1
• Filed: 05/11/2004
• Published: 12/09/2004
• Est. Priority Date: 06/09/2003
• Status: Active Grant

• Current Assignee: Sumitomo Rubber Industries Limited
• Original Assignee: Sumitomo Rubber Industries Limited
• Inventors: Yanase, Minao
• Granted Patent: US 7,305,288 B2
• Time in Patent Office: Days
• US Class Current: 701/29
• CPC Class Codes: B60C 23/061 by monitoring wheel speed measuring distance traversed on the ground by vehicles G01C22/00

Abstract

A method for detecting decrease in tire air-pressure on the basis of wheel rotational information obtained from tires attached to a four-wheeled vehicle. The method includes the steps of: obtaining wheel rotational information obtainable from the respective tires, storing the wheel rotational information, and judging decrease in air-pressure of a tire. The step of judging decrease in air-pressure includes the step of adjusting a sensitivity of judgment upon multiplying a specified sensitivity coefficient to the wheel rotational information of the respective wheels of a front axis or those of the respective wheels of a rear axis of the vehicle and of judging a running condition of the vehicle. When it is determined that the vehicle is performing straight-ahead running, the judgment of decrease in tire air-pressure is performed only on the basis of wheel rotational information when performing straight-ahead running. It is possible to maintain detection accuracy of decrease in tire air-pressure and to prevent erroneous alarm.

Claims

1. A method for detecting decrease in tire air-pressure on the basis of wheel rotational information obtained from tires attached to a four-wheeled vehicle, comprising the steps of:

obtaining wheel rotational information which can be obtained from the respective tires;

storing the wheel rotational information; and

judging decrease in air-pressure of a tire,

wherein the step of judging decrease in air-pressure includes the step of adjusting a sensitivity of judgment upon multiplying a specified sensitivity coefficient to the wheel rotational information of the respective wheels of a front axis or those of the respective wheels of a rear axis of the vehicle and of judging a running condition of the vehicle, and

wherein when it is determined that the vehicle is performing straight-ahead running, the judgment of decrease in tire air-pressure is performed only on the basis of wheel rotational information when performing straight-ahead running.

2. A method for detecting decrease in tire air-pressure on the basis of wheel rotational information obtained from tires attached to a four-wheeled vehicle, comprising the steps of:

obtaining wheel rotational information which can be obtained from the respective tires;

storing the wheel rotational information; and

judging decrease in air-pressure of a tire,

wherein the step of judging decrease in air-pressure includes the step of adjusting a sensitivity of judgment upon multiplying a specified sensitivity coefficient to the wheel rotational information of the respective wheels of a front axis or those of the respective wheels of a rear axis of the vehicle and of judging a running condition of the vehicle, and

wherein a judged value for judging decrease in tire air-pressure when performing turning movements is corrected when it is determined that the vehicle is performing turning movements.

3. An apparatus for detecting decrease in tire air-pressure in which decrease in tire air-pressure is detected on the basis of wheel rotational information obtained from tires attached to a four-wheeled vehicle, comprising:

rotational information detecting means which obtain wheel rotational information obtainable from the respective tires;

a storing means which stores the wheel rotational information; and

a decompression judging means which judges decrease in air-pressure of a tire,

wherein the decompression judging means includes a sensitivity adjusting means which adjusts a sensitivity of judgment upon multiplying a specified sensitivity coefficient to the wheel rotational information of the respective wheels of a front axis or those of the respective wheels of a rear axis of the vehicle, a running judging means which judges a running condition of the vehicle, and a decompression judgment starting means which performs judgment of decrease in tire air-pressure, when it is determined that the vehicle is performing straight-ahead running, only on the basis of wheel rotational information when performing straight-ahead running.

4. An apparatus for detecting decrease in tire air-pressure in which decrease in tire air-pressure is detected on the basis of wheel rotational information obtained from tires attached to a four-wheeled vehicle, comprising:

rotational information detecting means which obtain wheel rotational information obtainable from the respective tires;

a storing means which stores the wheel rotational information; and

a decompression judging means which judges decrease in air-pressure of a tire,

wherein the decompression judging means includes a sensitivity adjusting means which adjusts a sensitivity of judgment upon multiplying a specified sensitivity coefficient to the wheel rotational information of the respective wheels of a front axis or those of the respective wheels of a rear axis of the vehicle, a running judging means which judges a running condition of the vehicle, and a correcting means which corrects the judged value when performing turning movements obtained by the compression judging means when it is determined that the vehicle is performing turning movements.

5. A program for judging decompression of a tire, in which for judging decrease in tire air-pressure on the basis of wheel rotational information obtained from tires attached to a four-wheeled vehicle, a computer is made to function as a storing means which stores the wheel rotational information, a decompression judging means which judges decrease in air-pressure of a tire, a sensitivity adjusting means which adjusts a sensitivity of judgment upon multiplying a specified sensitivity coefficient to the wheel rotational information of the respective wheels of a front axis or those of the respective wheels of a rear axis of the vehicle, a running judging means which judges a running condition of the vehicle, and a decompression judgment starting means which performs judgment of decrease in tire air-pressure, when it is determined that the vehicle is performing straight-ahead running, only on the basis of wheel rotational information when performing straight-ahead running.

6. A program for judging decompression of a tire, in which for judging decrease in tire air-pressure on the basis of wheel rotational information obtained from tires attached to a four-wheeled vehicle, a computer is made to function as a storing means which stores the wheel rotational information, a decompression judging means which judges decrease in air-pressure of a tire, a sensitivity adjusting means whch adjusts a sensitivity of judgment upon multiplying a specified sensitivity coefficient to the wheel rotational information of the respective wheels of a front axis or those of the respective wheels of a rear axis of the vehicle, a running judging means which judges a running condition of the vehicle, and a correcting means which corrects the judged value when performing turning movements obtained by the compression judging means when it is determined that the vehicle is performing turning movements.