APPARATUS AND METHOD FOR DETECTING AN INTERNAL MECHANICAL FAILURE OCCURRING IN A TIRE

Abstract

An apparatus and method derives a deformation amount of a contact-portion of the tire based on the tire information, the contact-portion being in contact with the ground, and calculates an evaluation value based on the derived deformation amount, and comparing the calculated evaluation value with a reference value to determine whether or not the internal mechanical failure has occurred in the tire.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

In the accompany drawings:

FIG. 1 is a schematic structural view illustrating an example of a tire internal mechanical failure detection apparatus according to an embodiment of the present invention;

FIG. 2 is a view illustrating a sensor unit and a data processing unit in the tire internal mechanical failure detection apparatus shown in FIG. 1;

FIGS. 3A and 3B are views illustrating a force applied to a portion of a tire that is in contact with the ground while a vehicle is traveling, in which: FIG. 3A is a view showing a tire of a vehicle shown in FIG. 1 seen from a road surface side; and FIG. 3B is a graph showing a deformation amount in a time series in a circumferential direction of the tire and a deformation amount in a time series in a width direction of the tire, respectively;

FIG. 4 is a graph illustrating an example of an evaluation value in the present invention;

FIG. 5 is a flowchart illustrating a tire internal mechanical failure detection method according to this embodiment of the present invention;

FIGS. 6A to 6C are diagrams showing an example of the results obtained by the processing in a processing part of the data processing unit shown in FIG. 2;

FIGS. 7A to 7C are diagrams showing an example of the results obtained by the processing in a deriving part of the data processing unit shown in FIG. 2; and

FIGS. 8A to 8D are diagrams illustrating the effects of the tire internal mechanical failure detection method of the present invention, showing circumferential direction deformation amount data and width direction deformation amount data on predetermined portions of respective surfaces of a tire A and a tire B.

Claims

1. An apparatus for detecting an internal mechanical failure of a tire that is attached to a wheel of a vehicle while the vehicle is traveling, including: an information acquiring part for acquiring tire information on the tire during rotating while the vehicle is traveling;a deriving part for deriving a deformation amount of a contact-portion of the tire based on the tire information, the contact-portion being in contact with the ground;a calculating part for calculating an evaluation value based on the derived deformation amount; anda determining part for comparing the calculated evaluation value with a reference value to determine whether or not the internal mechanical failure has occurred in the tire.

2. The apparatus according to claim 1, wherein the information acquiring part acquires acceleration data of a predetermined portion of the tire in time series as the tire information, said acceleration generated when the tire receives an external force from a road surface while the vehicle is traveling, and wherein the deriving part obtains the deformation amount of the contact-portion by using the acceleration data of the tire in time series acquired in the information acquiring part.

3. The apparatus according to claim 2, further including an acceleration sensor placed on an inner surface of the predetermined portion of the tire for measuring the acceleration data of the predetermined portion.

4. The apparatus according to claim 3, further including a transmitter provided in the wheel, the transmitter transmitting the acceleration data measured by the acceleration sensor to the information acquiring part by wireless; and wherein the information acquiring part includes a receiver for receiving the acceleration data transmitted by wireless.

5. The apparatus according to claim 2, wherein the deriving part extracts acceleration data due to a deformation of the tire in time series from the acceleration data, and performs a second-order time integration with respect to the acceleration data due to the deformation of the tire to obtain displacement data, thereby calculating the deformation amount of the tire.

6. The apparatus according to claim 1, wherein the deriving part obtains deformation amounts of the contact-portion in a tire circumferential direction and a tire width direction, and wherein the calculating part calculates the evaluation value based on the deformation amounts in said two directions.

7. The apparatus according to claim 6, wherein the calculating part calculates a value represented by using one of Xmax/Ymax and Ymax/Xmax as the evaluation value, Xmax being a maximum value of the deformation amount of the contact-portion in the tire circumferential direction, and Ymax being a maximum value of the deformation amount of the contact-portion in the tire width direction

8. The apparatus according to claim 7, wherein the calculating part calculates a value represented by using one of tan−1(Xmax/Ymax) and tan−1(Ymax/Xmax) as the evaluation value.

9. The apparatus according to claim 6, wherein the calculating part calculates a value represented by Xmax×Ymax as the evaluation value, Xmax being a maximum value of the deformation amount of the contact-portion in the tire circumferential direction, and Ymax being a maximum value of the deformation amount of the contact-portion in the tire width direction

10. The apparatus according to claim 1, wherein the deriving part derives the deformation amount of the contact-portion in a tire circumferential direction, and wherein the calculating part calculates the evaluation value based on a maximum value of the deformation amount of the contact-portion in the tire circumferential direction.

11. The apparatus according to claim 1, wherein the deriving part derives the deformation amount of the contact-portion in a tire width direction, and wherein the calculating part calculates the evaluation value based on a maximum value of the deformation amount of the contact-portion in the tire width direction.

12. A method of detecting an internal mechanical failure of a tire that is attached to a wheel of a vehicle while the vehicle is traveling, including: an information acquiring step of acquiring tire information on the tire during rotating while the vehicle is traveling;a deriving step of deriving a deformation amount of a contact-portion of the tire based on the tire information, the contact-portion being in contact with the ground;a calculating step of calculating an evaluation value based on the derived deformation amount; anda determining step of comparing the calculated evaluation value with a reference value to determine whether or not the internal mechanical failure has occurred in the tire.