US5352352A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Carbonic acid gas sensor
Assignee: Hitachi Ltd
•
Filing: 1992-09-23
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Granted: 1994-10-04
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Expires: 2012-09-23
Abstract
Abstract A sensor for detecting a carbonic acid gas dissolved in body fluids has a laminated structure including an outer plate having a carbonic acid gas permeable window, a plate for a pH-electrode having a pH sensitive membrane, an intermediate plate having a cavity for accommodating an electrolyte, and a plate for a reference electrode. The plate for the pH-electrode is constituted in a manner that a pH sensitive membrane constituted by a membrane of an oxide of a platinum group metal is formed on an insulating substrate and the electrolyte contacts with the pH sensitive membrane in a groove. The pH sensitive membrane is disposed so as to oppose to the carbonic acid gas permeable window.
Inventors
- 👤 Keiji Tsukada
- 👤 Yuji Miyahara
- 👤 Yasuhisa Shibata
- 👤 Yoshio Watanabe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 13:55
CPC Classifications
A; A61; A61B; A61B5/00; A61B5/145; A61B5/14542; A61B5/14539; A61B5/1468; G; G01; G01N; G01N27/00; G01N27/26; G01N27/403; G01N27/404; G01N27/4045; G01N33/00; G01N33/48; G01N33/483; G01N33/487; G01N33/49; G01N33/4925
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
123 words
A carbonic acid gas sensor capable of detecting carbonic acid gas dissolved in fluid, comprising: an outer plate including first and second glass substrates each having a window formed therein and fixedly sandwiching a gas permeable membrane to form a carbonic acid gas permeable window; a first supporting plate supporting a pH-electrode, for detecting a pH of an electrolyte, including an insulating substrate, a pH sensitive membrane formed on said substrate so as to oppose said carbonic acid gas permeable window, and a compartment for accommodating the electrolyte, said compartment extending through the thickness of said first supporting plate; and a second supporting plate supporting a reference electrode, wherein said outer plate, said first supporting plate and said second supporting plate are laminated.
Claim 2
Dependent Claim
123 words
A carbonic acid gas sensor capable of detecting carbonic acid gas dissolved in fluid, comprising: an outer plate including first and second glass substrates each having a window formed therein and fixedly sandwiching a gas permeable membrane to form a carbonic acid gas permeable window; a first supporting plate supporting a pH-electrode, for detecting a pH of an electrolyte, including an insulating substrate, a pH sensitive membrane formed on said substrate so as to oppose said carbonic acid gas permeable window, and a compartment for accommodating the electrolyte, said compartment extending through the thickness of said first supporting plate; and a second supporting plate supporting a reference electrode, wherein said outer plate, said first supporting plate and said second supporting plate are laminated.
Claim 3
Dependent Claim
24 words
A carbonic acid gas sensor according to claim 1, wherein said pH sensitive membrane is formed by an oxide of a platinum group metal.
Claim 4
Dependent Claim
16 words
A carbonic acid gas sensor according to claim 2, wherein said oxide is a palladium oxide.
Claim 5
Dependent Claim
16 words
A carbonic acid gas sensor according to claim 2, wherein said oxide is an iridium oxide.
Claim 6
Dependent Claim
16 words
A carbonic acid gas sensor according to claim 2, wherein said oxide is a platinum oxide.
Claim 7
Dependent Claim
19 words
A carbonic acid gas sensor according to claim 1, wherein said pH sensitive membrane is an indium oxide membrane.
Claim 8
Dependent Claim
51 words
A carbonic acid gas sensor according to claim 1, wherein said first supporting plate further includes a conductive layer formed on said insulating substrate and to be connected to an external lead wire, and said pH sensitive membrane is disposed on said conductive layer so as to cover a part thereof.
Claim 9
Dependent Claim
48 words
A carbonic acid gas sensor according to claim 7, wherein each of said first supporting plate and said second supporting plate has a through hole for wiring, and the lead wire connected to said conductive layer is extracted out of said second supporting plate through said through holes.
Claim 10
Dependent Claim
21 words
A carbonic acid gas sensor according to claim 1, wherein said pH sensitive membrane contacts with the electrolyte in said compartment.
Claim 11
Dependent Claim
51 words
A carbonic acid gas sensor according to claim 1, wherein said compartment of said first supporting plate includes a hole formed in said insulating substrate and a groove formed at a part of a composite resin layer covering the surface of said insulating substrate, and said groove communicates with said hole.
Claim 12
Dependent Claim
33 words
A carbonic acid gas sensor according to claim 1, further comprising an intermediate plate having a cavity for accommodating the electrolyte and disposed between said first supporting plate and said second supporting plate.
Claim 13
Dependent Claim
30 words
A carbonic acid gas sensor according to claim 1, wherein an exposed area of said pH sensitive membrane is smaller than an area of said carbonic acid gas permeable window.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-10-03 | 1998-04-04 | 1998-10-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-10-03 | 2002-04-04 | 2002-10-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-10-03 | 2006-04-04 | 2006-10-04 | $7700.00 | Window Closed / Lapsed |