Method for inspection of polymeric material with ferrous reinforcement to determine presence of reinforcement joint or damage

Patent metadata

Field	Value
Publication number	US-11175262-B2
Application number	US-201716625653-A
Country	US
Kind code	B2
Filing date	Jun 30, 2017
Priority date	Jun 30, 2017
Publication date	Nov 16, 2021
Grant date	Nov 16, 2021

Abstract

The present disclosure describes methods of inspecting polymeric material that includes one or more elongated ferrous reinforcements. The method includes applying a magnetic field to any one or more reinforcements. The method further includes positioning an array of magnetic flux sensors near the one or more reinforcements, and detecting the presence of magnetic flux leakage along any of the one or more reinforcements. It is then determined whether the magnetic flux leakage occurs at a damaged location along the one or more reinforcements or at a reinforcement joint.

First claim

What is claimed is:

1. A method of inspecting polymeric material within a tire, the polymeric material including one or more elongated ferrous reinforcements, the method comprising:
applying a magnetic field to any one or more reinforcements, each of the one or more reinforcements being an elongated ferrous reinforcement;
positioning an array of magnetic flux sensors near the one or more reinforcements;
detecting magnetic flux leakage along any of the one or more reinforcements; and,
determining if the magnetic flux leakage occurs at a damaged location along the one or more reinforcements or at a reinforcement joint, where the step of determining if the magnetic flux leakage occurs at a damaged location or at a reinforcement joint includes:
determining whether an amplitude of the magnetic flux leakage is at or above a threshold minimum amplitude value;
determining whether a width of the magnetic flux leakage is within a threshold width range;
determining whether the width of each magnetic flux leakage is sufficiently symmetric by being within a threshold width symmetry range;
determining whether a difference between a leading slope and a trailing slope of the magnetic flux leakage is less than a threshold slope limit;
inspecting externally the tire for any visible external physical damage at the location of the magnetic flux leakage; and,
determining that the magnetic flux leakage occurs at a reinforcement joint if:
the amplitude is at or above the threshold minimum amplitude value;
the width of the magnetic flux leakage is within the threshold width range;
the width of each magnetic flux leakage is sufficiently symmetric by being within the threshold width symmetry range;
the difference between the leading slope and the trailing slope of the magnetic flux leakage is less than the threshold slope limit; and,
no external physical damage is observed at the location of the magnetic flux leakage.

2. The method of claim 1 , where the threshold minimum amplitude value is 0.03 volts.

3. The method of claim 1 , where in determining that the magnetic flux leakage is a joint, the amplitude is also less than a threshold maximum amplitude value.

4. The method of claim 3 , where the threshold maximum amplitude value is 0.2 volts.

5. The method of claim 1 , where the threshold width range is 100 to 150 sample points.

6. The method of claim 5 , where the threshold width range is 100 to 170 sample points.

7. The method of claim 1 , where the threshold width symmetry range is an acceptable difference between a leading width and a trailing width.

8. The method of claim 7 , where the acceptable difference is up to a 25 sample point difference.

9. The method of claim 1 , where the threshold slope limit is less than a 0.0005 volt difference.

10. The method of claim 1 , where the step of determining if the magnetic flux leakage occurs at a damaged location or at a reinforcement joint further includes determining whether separate occurrences of magnetic flux leakage have been detected in the step of detecting along the tire and if so whether the separate occurrences are at or below a threshold maximum occurrence value, and where in determining that the magnetic flux leakage occurs at a reinforcement joint, it is determined that the separate occurrences are at or below the threshold maximum occurrence value.

11. The method of claim 1 , where prior to determining if the magnetic flux leakage occurs at a damaged location or at a reinforcement joint, the method includes:
determining a threshold minimum amplitude value, a threshold width range, a threshold width symmetry range, or a threshold slope limit.

12. A method of inspecting polymeric material within a tire, the polymeric material including one or more elongated ferrous reinforcements, the method comprising:
applying a magnetic field to any one or more reinforcements, each of the one or more reinforcements being an elongated ferrous reinforcement;
positioning an array of magnetic flux sensors near the one or more reinforcements;
detecting magnetic flux leakage along any of the one or more reinforcements; and,

determining if the magnetic flux leakage occurs at a damaged location along the one or more reinforcements or at a reinforcement joint,
where prior to determining if the magnetic flux leakage occurs at a damaged location or at a reinforcement joint, the method includes determining a threshold minimum amplitude value, a threshold width range, a threshold width symmetry range, or a threshold slope limit, and,
where in determining the threshold minimum amplitude value, the threshold width range, the threshold width symmetry range, or the threshold slope limit, magnetic field responsive sensor samplings taken from one or more other tires are evaluated in conjunction with a physical inspection of the tire at the location attributed to one or more detected anomaly to correlate a specific signal characteristic with the one or more anomalies that indicate a joint and with one or more anomalies that indicate reinforcement damage.

Assignees

• Michelin & Cie

Inventors

• Gramling Frank E
• Judd David A

Classifications

• G01N27/83 Primary

  by investigating stray magnetic fields · CPC title