Transparency having moisture sensors

Patent metadata

Field	Value
Publication number	US-9347905-B2
Application number	US-201314082857-A
Country	US
Kind code	B2
Filing date	Nov 18, 2013
Priority date	Nov 18, 2013
Publication date	May 24, 2016
Grant date	May 24, 2016

Abstract

A transparency, e.g. an aircraft laminated windshield, includes one or more moisture sensors to monitor moisture penetration to monitor performance of the moisture barrier. The moisture sensor includes a moisture corrodible article or sensor element, e.g. a strip or wire, which changes resistance as a function of corrosion. The sensor element can also include two dissimilar metals, e.g. a bimetal sensor element, or two similar metals having different physical dimensions. With the information provided by the moisture sensors performance of the windshield is available to schedule timely repair or replacement of the windshield that is performing outside of acceptable limits.

First claim

What is claimed is:

1. An aircraft transparency comprising:
a plurality of sheets joined together;
a moisture seal overlaying marginal edges of outer opposed surfaces, and peripheral edge, of the aircraft transparency, and the sensor element between the sheets and/or between the sheets and the moisture seal;
sensor element responsive to moisture, the sensor element between the sheets, wherein the sensor element is a first elongated moisture sensor having a first end and a second opposite end, and comprising second, third, and fourth elongated moisture sensors; each of the moisture sensors comprising a first end and an opposite second end, wherein the first, second, third and fourth moisture sensors are mounted on a major surface of one of the pair of sheets adjacent peripheral edge of the sheet, wherein the second end of the first sensor is adjacent and spaced from the first end of the second sensor, the second end of the second sensor is adjacent and spaced from the first end of the third sensor, the second end of the third sensor is adjacent and spaced from the first end of the fourth sensor, and the second end of the fourth sensor is adjacent and spaced from the first end of the first sensor;
sensor electronics operatively connected to the sensor to measure an electrical property of the sensor that changes as a function of corrosion caused by moisture, wherein
operatively connecting the sensor element and the sensor electronics to a power source to measure the electrical property of the sensor to determine if the sensor element is a new sensor element, an operating sensor element, a saturated sensor element, or a broken sensor element.

2. The transparency according to claim 1 , wherein the transparency is an aircraft transparency and each of the sheets comprises a first major surface opposite to a second major surface and a peripheral surface joining the first major surface, wherein the second surface of the first sheet is in facing relationship to and spaced from the second surface of the second sheet and the sensor element is between the first sheet and the second sheet, and spaced from the peripheral edge of the first sheet and the second sheet.

3. The transparency according to claim 1 comprising:
the plurality of sheets comprises two or more transparent sheets joined together by an adhesive, and
the sensor element on a surface portion of at least one of the sheets.

4. The transparency according to claim 3 wherein each of the sheets comprises a first major surface opposite to a second major surface and a peripheral surface joining the first major surface and the second major surface, wherein the surface portion of the at least one of the sheets is selected from the group of the first major surface, the second major surface, the peripheral surface and combinations thereof.

5. The transparency according to claim 3 , wherein the sensor element is a pair of wires twisted around one another.

6. The transparency according to claim 5 wherein the first, second, third and fourth elongated sensors form a first boundary and comprising a second boundary within and spaced from the first boundary, and a third boundary within and spaced from the second boundary, wherein each of the second and third boundaries comprises at least one elongated moisture sensor defined as a fifth elongated moisture sensor for the second boundary and the sixth elongated moisture sensor for the third boundary.

7. A transparency comprising;
a plurality of sheets joined together;
sensor element responsive to moisture, the sensor element between the sheets, wherein the sensor element is a metal strip that corrodes in the presence of moisture, and the ohm resistance measured increases as the corrosion increases;
sensor electronics operatively connected to the sensor to measure an electrical property of the sensor that changes as a function of corrosion caused by moisture, wherein
operatively connecting the sensor element and the sensor electronics to a power source to measure the electrical property of the sensor to determine if the sensor element is a new sensor element, an operating sensor element, a saturated sensor element, or a broken sensor element.

8. The transparency according to claim 7 wherein the sensor element includes two strips of the same metal having different widths.

9. The transparency according to claim 7 , wherein the transparency is selected from the group of a laminated aircraft transparency, commercial and residential windows, a window for any type of and vehicle; a canopy, cabin window and windshield for any type of air and space vehicle, a window for any above or below water vessel, and a window for a viewing side or door for any type of containers.

10. The transparency according to claim 9 wherein the sheets of the transparency are selected from the group of uncured plastic sheets; annealed glass sheets, and heat and chemically strengthened, clear, colored, coated and uncoated glass sheets.

11. A transparency comprising:
a plurality of sheets joined together;
a sensor element responsive to moisture, the sensor element between the sheets, wherein the sensor element is a bimetallic strip of two metals that corrodes in the presence of moisture, and the ohm resistance of each of the two metals measured increases as the corrosion increases and the ohm resistance of each metal differs;
sensor electronics operatively connected to the sensor to measure an electrical property of the sensor that changes as a function of corrosion caused by moisture, wherein
operatively connecting the sensor element and the sensor electronics to a power source to measure the electrical property of the sensor to determine if the sensor element is a new sensor element, an operating sensor element, a saturated sensor element, or a broken sensor element.

12. The transparency according to claim 11 wherein the bimetallic strips is selected from the groups of pairs of wires comprises Iron/Zinc; Chromel/Iron; Chromel/Aluminum; Chromel/Zinc; Iron/Copper; Nikrothal/Iron; Cuprothal/Iron; Kanthal/Iron, and Nifethal/Iron.

13. The transparency according to claim 11 wherein the strips overlay one another and are electrically isolated from one another.

14. The transparency according to claim 11 wherein the strips overlay one another and are electrically connected to one another.

15. The transparency according to claim 11 wherein one of the strips is a cathodic strip and other one of the strips is a anodic strip, and the cathodic strip has a resistivity higher than the resistivity of the anodic strip, and the anodic strip has a width greater than the width of the cathodic wire.

16. The transparency according to claim 11 wherein the bimetallic strips are paired to be on the opposite ends of the galvanic potential spectrum to allow the greatest reaction possibility.

17. The transparency according to claim 11 wherein the sensor element is one of a plurality of sensor elements, wherein a first one of the plurality of sensor elements is between the moisture seal and the sheets, and a third one of the plurality of sensor elements is between the moisture seal and outer surface portion of the aircraft transparency.

18. A method of determining life expectancy of a laminated aircraft transparency having moisture penetration, comprising:
fabricating a laminated aircraft transparency having a moisture barrier over outer surface of the marginal edges of, and periphery of the laminated aircraft transparency;
during fabrication of the laminated aircraft transparency placing a sensor element responsive to mois

Assignees

• Ppg Ind Ohio Inc

Inventors

• Jiao Yu
• Duarte Nicolas Benjamin
• Acord Jeremy D

Classifications

• B32B17/10137

  Chemical strengthening · CPC title

• B32B17/10394 Primary

  Alarm wires · CPC title

• B32B17/1077

  containing polyurethane · CPC title

• B32B17/10036

  comprising two outer glass sheets · CPC title

• B32B2255/26

  Polymeric coating · CPC title