Tire deflation warning system and method thereof, and judgment program of tire with reduced pressures

• US 20060006014A1
• Filed: 06/22/2005
• Published: 01/12/2006
• Est. Priority Date: 07/12/2004
• Status: Active Grant

• Current Assignee: Sumitomo Rubber Industries Limited
• Original Assignee: Sumitomo Rubber Industries Limited
• Inventors: Yanase, Minao
• Granted Patent: US 7,333,008 B2
• Time in Patent Office: Days
• US Class Current: 180/197
• CPC Class Codes: B60C 23/061 by monitoring wheel speed measuring distance traversed on the ground by vehicles G01C22/00

Abstract

A tire deflation warning system having a means for detecting the rotational speeds of wheels on a vehicle and a means for judging tires with reduced air pressure from the rotational speed information of the wheels including a means for judging whether driving force works to respective wheels or not a means for calculating a vehicle speed when driving force works to respective wheels, a means for comparing the average of the rotational speeds of the driving wheels against the average of the rotational speeds of the following wheels, with the average of the rotational speeds of the driving wheels against the average of the rotational speeds of the following wheels at normal air pressure in running state in which the vehicle has driving force and a means for judging that the air pressures of the all wheels which are mounted on the vehicle are simultaneously reduced, or that the air pressures of the driving wheels are reduced by the result of the comparison.

Claims

1. A tire deflation warning system comprising a means for detecting the rotational speeds of wheels on a vehicle and a means for judging tires with reduced air pressure from the rotational speed information of the wheels comprising:

a means for judging whether driving force works to respective wheels or not;

a means for calculating a vehicle speed when driving force works to respective wheels;

a means for comparing the average of the rotational speeds of the driving wheels against the average of the rotational speeds of the following wheels, with the average of the rotational speeds of the driving wheels against the average of the rotational speeds of the following wheels at normal air pressure in running state in which the vehicle has driving force; and

a means for judging that the air pressures of the all wheels which are mounted on the vehicle are simultaneously reduced, or that the air pressures of the driving wheels are reduced by the result of the comparison.

2. A tire deflation warning system according to claim 1, wherein the average of the rotational speeds of the driving wheels against the average of the rotational speeds of the following wheels at the normal air pressure is changed in accordance with acceleration and deceleration of the vehicle.

3. A judgment method for tires with reduced air pressure which judges tires with reduced air pressure using the rotational speed information of wheels mounted on a vehicle comprising the steps of:

judging whether driving force works to respective wheels or not;

calculating a vehicle speed when driving force works to respective wheels;

comparing the average of the rotational speeds of the driving wheels against the average of the rotational speeds of the following wheels, with the average of the rotational speeds of the driving wheels against the average of the rotational speeds of the following wheels at normal air pressure in running state in which the vehicle has driving force; and

judging that the air pressures of the all wheels which are mounted on the vehicle are simultaneously reduced, or that the air pressures of the driving wheels are reduced by the result of the comparison.

4. A judgment method for tires with reduced air pressure according to claim 3, wherein the average of the rotational speeds of the driving wheels against the average of the rotational speeds of the following wheels at the normal air pressure is changed in accordance with acceleration and deceleration of the vehicle.

5. A judgment program of the reduced pressures of tires for functionalizing a computer as a memory means of memorizing the rotational speeds of wheels mounted on a vehicle comprising;

a means for judging whether driving force works to respective wheels or not;

a means for calculating a vehicle speed when driving force works to respective wheels; and

a means for detecting that the air pressures of the all wheels which are mounted on the vehicle are reduced, or that the air pressures of the driving wheels are reduced by comparing the average of the rotational speeds of the driving wheels against the average of the rotational speeds of the following wheels, with the average of the rotational speeds of the driving wheels against the average of the rotational speeds of the following wheels at normal air pressure in running state in which the vehicle has driving force, in order to judge tires with reduced air pressure.

6. A judgment program of the reduced pressures of tires according to claim 5, wherein the average of the rotational speeds of the driving wheels against the average of the rotational speeds of the following wheels at the normal air pressure is changed in accordance with acceleration and deceleration of the vehicle.