Sensor device

• US 10,393,688 B2
• Filed: 10/28/2015
• Issued: 08/27/2019
• Est. Priority Date: 05/13/2011
• Status: Active Grant

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Kato, Juri, Miyazawa, Takao
• Primary Examiner(s): Hollington, Jermele M
• Assistant Examiner(s): Curtis, Sean
• Application Number:
  US14/924,856
• Publication Number:
  US 20160103086A1
• Time in Patent Office: 1,399 Days
• Field of Search: 324 38, 324457, 324649, 324700, 324 711, 2057755, 205789
• CPC Class Codes: G01N 17/02 Electrochemical measuring systems for weathering, corrosion or corrosion-protection measurement
• CPC Class Codes: G01N 17/04 Corrosion probes
• CPC Class Codes: G01N 27/048 for determining moisture content of the material
• CPC Class Codes: G01N 27/125 Composition of the body, e.g. the composition of its sensitive layer
• CPC Class Codes: G01N 27/4167 pH electrodes therefor G01N27/302, G01N27/36
• CPC Class Codes: G01N 33/208 Coatings, e.g. platings
• CPC Class Codes: G01N 33/383 Concrete, cement

Abstract

A sensor device includes a first electrode, a second electrode, and a functional element. The first electrode includes a porous body having holes in at least the vicinity of a surface of the first electrode, and includes a first metallic material in which either a first passivation film is formed on the surface or the first passivation film present on the surface is lost. The second electrode spaced apart from the first electrode includes a porous body having holes in at least the vicinity of a surface of the second electrode. The functional element is configured to measure a difference in electric potential between the first and second electrodes. A porosity of the first electrode and a porosity of the second electrode are different from each other. The sensor device is configured to measure a state of a site to be measured based on the difference in electric potential.

Claims

1. A sensor device comprising:

a first electrode including a porous body that has a plurality of holes in at least the vicinity of a surface of the first electrode, the first electrode including

a substrate having a first metallic material in which either a first passivation film is formed on the surface of the first electrode or the first passivation film present on the surface of the first electrode is lost, and

a conductive film disposed on the substrate, extending along outer peripheries of the holes, and covering the outer peripheries of the holes, the conductive film having a material different from the first metallic material of the substrate;

a second electrode spaced apart from the first electrode, the second electrode including a porous body that has a plurality of holes in at least the vicinity of a surface of the second electrode, the second electrode including a material different from the first metallic material; and

a functional element configured to measure a difference in electric potential between the first electrode and the second electrode,

the sensor device being configured to measure a state of a site to be measured based on the difference in electric potential as measured by the functional element.

2. The sensor device according to claim 1, wherein

the first and second electrodes include the porous bodies that have a series of holes that are adjacent with respect to each other and communicate with each other, respectively.

3. The sensor device according to claim 1, wherein

the material of the second electrode is a second metallic material in which a second passivation film is formed.

4. The sensor device according to claim 3, wherein

the second electrode includes the second metallic material in which either the second passivation film is formed on the surface of the second electrode or the second passivation film present on the surface of the second electrode is lost according to environment of the site to be measured, and the environment is different from environment of the site to be measured according to which either the first passivation film is formed on the surface of the first electrode or the first passivation film present on the surface the first electrode is lost in the first metallic material.

5. The sensor device according to claim 3, wherein

the first metallic material is iron or an iron-based alloy.

6. The sensor device according to claim 2, wherein

the second electrode includes a substrate and a conductive film that is disposed on the substrate and includes a material different from a material of the substrate of the second electrode.

7. The sensor device according to claim 1, wherein

the conductive film includes a metallic material in which either a passivation film is formed on a surface thereof or a passivation film present on a surface thereof is lost, in association with changes in environment of the site to be measured.

8. The sensor device according to claim 1, wherein

the functional element is further configured to detect whether or not pH or chloride ion concentration at the site to be measured is at or below a set value, based on the difference in electric potential between the first electrode and the second electrode.

9. The sensor device according to claim 1, further comprising

an antenna and a communication circuit configured to provide power to the antenna,

the functional element being further configured to drive and control the communication circuit.

10. The sensor device according to claim 4, wherein

the first metallic material of the first electrode has a first range of pHs where the first passivation film is formed, the second metallic material of the second electrode has a second range of pHs where the second passivation film is formed, the first range of pHs has a first passivation pH that is a lower limit of the first range of pHs, and the second range of pHs has a second passivation pH that is a lower limit of the second range of pHs and different from the first passivation pH.

11. The sensor device according to claim 1, wherein

a porosity of the first electrode and a porosity of the second electrode are different from each other.

12. The sensor device according to claim 3, wherein

the second metallic material is iron or an iron-based alloy.