Method of detection of limited slip differential device, method and apparatus for detecting decrease in tire air-pressure employing the method of detection, and program for judging decompression of tire

• US 20030128110A1
• Filed: 12/30/2002
• Published: 07/10/2003
• Est. Priority Date: 01/09/2002
• Status: Active Grant

• Current Assignee: Sumitomo Electric Industries Limited (Sumitomo Corporation), Sumitomo Rubber Industries Limited
• Original Assignee: Sumitomo Electric Industries Limited (Sumitomo Corporation), Sumitomo Rubber Industries Limited
• Inventors: Sugisawa, Toshifumi
• Granted Patent: US 6,907,327 B2
• Time in Patent Office: Days
• US Class Current: 340/443
• CPC Class Codes: B60C 23/061 by monitoring wheel speed measuring distance traversed on the ground by vehicles G01C22/00

Abstract

A method of detection of the limited slip differential device, wherein it is detected whether a vehicle is mounted with a limited slip differential device on the basis of a relationship between a lateral directional acceleration of a vehicle calculated by using rotational information obtained from tires attached to the vehicle or on the basis of a turning radius of the vehicle, and a specified judged value. It is possible to improve performance and safety of the vehicle since it is possible to accurately judge decrease in internal pressure of a tire.

Claims

1. A method of detection of the limited slip differential device, wherein it is detected whether a vehicle is mounted with a limited slip differential device on the basis of a relationship between a lateral directional acceleration of a vehicle calculated by using rotational information obtained from tires attached to the vehicle or a turning radius of the vehicle, and a specified judged value.

2. The method of claim 1, wherein the judged value is a value obtained by using an equation in which a difference between average values of sums of rotational information of two wheels respectively disposed on diagonal lines of the wheels of the four-wheeled vehicle is divided by an average value of rotational information of the four wheels, or other equations which are equivalent to the equation.

3. The method of claim 2, wherein it is determined whether the vehicle is mounted with a limited slip differential device on the basis of magnitude of inclination of a linear equation obtained from a relationship between the lateral directional acceleration or the turning radius and a specified judged value.

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

detecting rotational information of the respective tires;

storing the rotational information of the respective tires;

calculating a lateral directional acceleration of the vehicle or a turning radius of the vehicle;

detecting whether the vehicle is mounted with a limited slip differential device on the basis of a relationship between the lateral directional acceleration or the turning radius and a specified judged value; and

judging decrease in air-pressure of the tire by selecting a threshold for judging decompression on the basis of the detection.

5. The method of claim 4, wherein the judged value is a value obtained by using an equation in which a difference between average values of sums of rotational information of two wheels respectively disposed on diagonal lines of the wheels of the four-wheeled vehicle is divided by an average value of rotational information of the four wheels, or other equations which are equivalent to the equation.

6. The method of claim 5, wherein it is determined whether the vehicle is mounted with a limited slip differential device on the basis of magnitude of inclination of a linear equation obtained from a relationship between the lateral directional acceleration or the turning radius and a specified judged value.

7. An apparatus for detecting decrease in air-pressure of a tire to detect decrease in internal pressure of a tire on the basis of rotational information obtained from tires attached to a vehicle, comprising:

rotational information detecting means for detecting rotational information of the respective tires;

a storing means for storing the rotational information of the respective tires;

a first calculating means for calculating a lateral directional acceleration of the vehicle or a turning radius of the vehicle;

a mount detecting means for detecting whether the vehicle is mounted with a limited slip differential device on the basis of a relationship between the lateral directional acceleration or the turning radius and a specified judged value; and

a decompression judging means for judging decrease in air-pressure of the tire by selecting a threshold for judging decompression on the basis of the detection.

8. The apparatus of claim 7, wherein the judged value is a value obtained by using an equation in which a difference between average values of sums of rotational information of two wheels respectively disposed on diagonal lines of the wheels of the four-wheeled vehicle is divided by an average value of rotational information of the four wheels, or other equations which are equivalent to the equation.

9. The apparatus of claim 8, wherein it is determined whether the vehicle is mounted with a limited slip differential device on the basis of magnitude of inclination of a linear equation obtained from a relationship between the lateral directional acceleration or the turning radius and a specified judged value.

10. A program for judging decompression of a tire, in which to judge decrease in air-pressure of a tire, a computer is made to function as a storing means for storing the rotational information of the respective tires;

a first calculating means for calculating a lateral directional acceleration of the vehicle or a turning radius of the vehicle;

a mount detecting means for detecting whether the vehicle is mounted with a limited slip differential device on the basis of a relationship between the lateral directional acceleration or the turning radius and a specified judged value; and

a decompression judging means for judging decrease in air-pressure of the tire by selecting a threshold for judging decompression on the basis of the detection.

11. The program of claim 10, wherein the judged value is a value obtained by using an equation in which a difference between average values of sums of rotational information of two wheels respectively disposed on diagonal lines of the wheels of the four-wheeled vehicle is divided by an average value of rotational information of the four wheels, or other equations which are equivalent to the equation.

12. The program of claim 11, wherein it is determined whether the vehicle is mounted with a limited slip differential device on the basis of magnitude of inclination of a linear equation obtained from a relationship between the lateral directional acceleration or the turning radius and a specified judged value.