US4470882A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gas leak detector
Assignee: Toshiba Corp
•
Filing: 1982-09-20
•
Granted: 1984-09-11
•
Expires: 2002-09-20
Abstract
Abstract Disclosed is a gas leak detector comprising; a tubular gas-sensitive element defining openings at both ends thereof, one end being a gas inlet and the other end a gas outlet, and made of an oxygen-ion conductive solid electrolyte; a set of electrodes provided respectively on the inner and outer walls of the gas-sensitive element, the electrode on the outer wall being kept in contact with a reference gas; a heater adapted to heat the gas-sensitive element to a predetermined temperature at a location corresponding to the set of electrodes; and a catalytic layer provided on the surface of the electrode on the inner wall being kept in contact with a target gas.
Inventors
- 👤 Masaki Katsura
- 👤 Mituo Harata
- 👤 Osamu Takikawa
- 👤 Masayuki Shiratori
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 08:43
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/26; G01N27/403; G01N27/406; G01N27/407; G01N27/4073; G01N27/4074; G01M; G01M3/00; G01M3/02; G01M3/04; G01M3/20; G01N27/4075
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
148 words
A process for the differential detection of halogenated hydrocarbon gas, comprising the steps of: (1) providing a tubular, oxygen-ion conductive, solid electrolyte comprising ZrO 2 , said tubular electrolyte defining an inner wall and an outer wall; (2) providing a first electrode on said inner wall and a second electrode on said outer wall, the surface of said first electrode being coated with a catalytic layer comprising V 2 O 5 -MoO 3 supported on α-Al 2 O 3 ; (3) exposing only said first electrode to a test gas in said tubular, oxygen ion-conductive, solid electrolyte, said test gas containing either a halogenated or a nonhalogenated hydrocarbon (4) detecting the presence of said halogenated hydrocarbon in said test gas by measuring a polarity at said first electrode relative to said second electrode which is opposite to a polarity measured when said test gas contains said nonhalogenated hydrocarbon.
Claim 2
Dependent Claim
148 words
A process for the differential detection of halogenated hydrocarbon gas, comprising the steps of: (1) providing a tubular, oxygen-ion conductive, solid electrolyte comprising ZrO 2 , said tubular electrolyte defining an inner wall and an outer wall; (2) providing a first electrode on said inner wall and a second electrode on said outer wall, the surface of said first electrode being coated with a catalytic layer comprising V 2 O 5 -MoO 3 supported on α-Al 2 O 3 ; (3) exposing only said first electrode to a test gas in said tubular, oxygen ion-conductive, solid electrolyte, said test gas containing either a halogenated or a nonhalogenated hydrocarbon (4) detecting the presence of said halogenated hydrocarbon in said test gas by measuring a polarity at said first electrode relative to said second electrode which is opposite to a polarity measured when said test gas contains said nonhalogenated hydrocarbon.
Claim 3
Independent Claim
135 words
A device for the differential detection of halogenated hydrocarbon gas comprising: a tubular gas-sensitive element defining openings at both ends thereof, one end bearing a gas inlet and the other end a gas outlet, and made of an oxygen-ion conductive solid electrolyte comprising ZrO 2 ; a set of electrodes provided respectively on the inner and outer walls of the gas-sensitive element, the electrode on the outer wall being kept in contact with a reference gas; a heater adapted to heat the gas-sensitive element to a predetermined temperature at a location corresponding to the set of electrodes; and a catalytic layer formed of V 2 O 5 -MoO 3 supported on α-Al 2 O 3 and covering directly the surface of the electrode on the inner wall being kept in contact with a target gas.
Claim 4
Independent Claim
135 words
A device for the differential detection of halogenated hydrocarbon gas comprising: a tubular gas-sensitive element defining openings at both ends thereof, one end bearing a gas inlet and the other end a gas outlet, and made of an oxygen-ion conductive solid electrolyte comprising ZrO 2 ; a set of electrodes provided respectively on the inner and outer walls of the gas-sensitive element, the electrode on the outer wall being kept in contact with a reference gas; a heater adapted to heat the gas-sensitive element to a predetermined temperature at a location corresponding to the set of electrodes; and a catalytic layer formed of V 2 O 5 -MoO 3 supported on α-Al 2 O 3 and covering directly the surface of the electrode on the inner wall being kept in contact with a target gas.
Claim 5
Dependent Claim
50 words
The device according to claim 1, wherein said catalytic layer comprises vanadium in an amount of from 0.1 to 50 wt % of the γ-Al 2 O 3 support and molybdenum in such an amount as to make the atomic ratio of molybdenum to said vanadium be 0.05 to 0.5.
Claim 6
Dependent Claim
35 words
The device according to claim 1, wherein a cover is provided on the outer surface of the gas-sensitive element so as to prevent the outer electrode from being in direct contact with the target gas.
Claim 7
Dependent Claim
33 words
The device according to claim 1, wherein said heater to provided on the outer electrode by burying it in an inorganic cement containing principally at least one of aluminum phosphate and sodium silicate.
Claim 8
Dependent Claim
25 words
The device according to claim 1, wherein said catalytic layer is formed by packing the catalyst in a hollow space corresponding to the inner electrode.
References Cited (Backward Citations)
US3658479A
Cited
US3870743A
Cited
US3981785A
Cited
US3871981A
Cited
US3936794A
Cited
US4059628A
Cited
US4113745A
Cited
JPS54146690A
Cited
US4269737A
Cited
JPS55132947A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-09-11 | 1988-03-12 | 1988-09-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-09-11 | 1992-03-12 | 1992-09-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-09-11 | 1996-03-12 | 1996-09-11 | $7700.00 | Window Closed / Lapsed |