Inspecting method and inspection apparatus for membraneelectrode assembly

Patent metadata

Field	Value
Publication number	US-11460417-B2
Application number	US-202117183739-A
Country	US
Kind code	B2
Filing date	Feb 24, 2021
Priority date	Feb 26, 2020
Publication date	Oct 4, 2022
Grant date	Oct 4, 2022

Abstract

A method of inspecting a membrane-electrode assembly includes obtaining an X-ray transmission image by applying X-rays to the membrane-electrode assembly, and determining whether a foreign matter having a size equal to or larger than a predetermined value is included in the membrane-electrode assembly, according to a brightness reduction amount in each pixel of the X-ray transmission image obtained, while referring to a correlative relationship between the size of the foreign matter measured in a planar direction of the membrane-electrode assembly, and the brightness reduction amount in the X-ray transmission image.

First claim

What is claimed is:

1. A method of inspecting a membrane-electrode assembly, comprising:
obtaining an X-ray transmission image by applying X-rays to the membrane-electrode assembly; and
determining whether a foreign matter having a size equal to or larger than a predetermined value is included in the membrane-electrode assembly, according to a brightness reduction amount in each of pixels of the X-ray transmission image obtained, while referring to a correlative relationship between the size of the foreign matter measured in a planar direction of the membrane-electrode assembly, and the brightness reduction amount in the X-ray transmission image.

2. The method according to claim 1 , further comprising:
preparing a plurality of foreign matter samples having different sizes measured in the planar direction;
obtaining the brightness reduction amount corresponding to each of the foreign matter samples, from the X-ray transmission image of each of the foreign matter samples; and
obtaining the correlative relationship in advance, from the brightness reduction amount obtained, and the size of each of the foreign matter samples.

3. A method of inspecting a membrane-electrode assembly, comprising:
obtaining an X-ray transmission image by applying X-rays to the membrane-electrode assembly;
obtaining a thickness of a foreign matter measured in a thickness direction of the membrane-electrode assembly, in each of pixels of the X-ray transmission image, according to a brightness reduction amount in each of the pixels of the X-ray transmission image, while referring to a correlative relationship between the thickness of the foreign matter and the brightness reduction amount in the X-ray transmission image, and specifying a shape of an object imaged in the X-ray transmission image, using the thickness in each of the pixels; and
determining whether the foreign matter is included in the membrane-electrode assembly, based on the shape.

4. The method according to claim 3 , further comprising:
preparing a plurality of foreign matter samples having different thicknesses measured in the thickness direction of the membrane-electrode assembly;
obtaining the brightness reduction amount corresponding to each of the foreign matter samples, from the X-ray transmission image of each of the foreign matter samples; and
obtaining the correlative relationship in advance, from the brightness reduction amount obtained, and the thickness of each of the foreign matter samples.

5. An inspection apparatus for a membrane-electrode assembly, comprising:
an obtaining unit configured to obtain an X-ray transmission image by applying X-rays to the membrane-electrode assembly; and
a determining unit configured to determine whether a foreign matter having a size equal to or larger than a predetermined value is included in the membrane-electrode assembly, according to a brightness reduction amount in each of pixels of the X-ray transmission image obtained by the obtaining unit, while referring to a correlative relationship between the size of the foreign matter measured in a planar direction of the membrane-electrode assembly, and the brightness reduction amount in the X-ray transmission image.

6. An inspection apparatus for a membrane-electrode assembly, comprising:
an obtaining unit configured to obtain an X-ray transmission image by applying X-rays to the membrane-electrode assembly; and
a determining unit configured to obtain a thickness of a foreign matter measured in a thickness direction of the membrane-electrode assembly, in each of pixels of the X-ray transmission image, according to a brightness reduction amount in each of the pixels of the X-ray transmission image obtained by the obtaining unit, while referring to a correlative relationship between the thickness of the foreign matter and the brightness reduction amount in the X-ray transmission image,
specify a shape of an object imaged in the X-ray transmission image, using the thickness in each of the pixels, and
determine whether the foreign matter is included in the membrane-electrode assembly, based on the shape.

Assignees

• Toyota Motor Co Ltd
• Hitachi High Tech Science Corp

Inventors

• Takeshita Shinya
• Takahara Toshiyuki
• Tatsumi Masaki

Classifications

• H01M8/1004 Primary

  characterised by membrane-electrode assemblies [MEA] (H01M8/12 takes precedence) · CPC title

• G01N23/083

  the radiation being X-rays · CPC title

• G01N23/18 Primary

  Investigating the presence of flaws defects or foreign matter · CPC title

• G01N23/04 Primary

  and forming images of the material · CPC title

• G01N23/16

  the material being a moving sheet or film · CPC title