Patent DE313126C successfully refreshed from Google Patents.
Patent US908169A successfully refreshed from Google Patents.
Patent DE54154C successfully refreshed from Google Patents.
Patent US4658632A successfully refreshed from Google Patents.
US4658632A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sensor
Assignee: Figaro Engineering Inc
•
Filing: 1985-12-10
•
Granted: 1987-04-21
•
Expires: 2005-12-10
Abstract
Abstract A λ sensor comprising a perovskite compound ASnO 3- δ and silica, germania, zirconia or hafnia added to the compound in an amount of 0.5 to 30 mol % per mol of the compound. Silica or like additive gives improved oxygen sensitivity and reduces the temperature dependence of the oxygen sensitivity.
Inventors
- 👤 Kazuko Sasaki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 12:15
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/02; G01N27/04; G01N27/12
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
95 words
A λ sensor comprising a metallic oxide semiconductor whose resistance value is varied by a gas, characterized in that the metallic oxide semiconductor is a compound ASnO 3- δ wherein A is at least one member selected from the group consisting of Ra, Ba, Sr and Ca, and δ is a non-stoichiometric parameter, the compound ASnO 3- δ having added thereto the dioxide of at least one element selected from the group consisting of silicon, germanium, zirconium and hafnium in an amount of 5 to 300 mmols per mol of the compound ASnO 3- δ.
Claim 2
Dependent Claim
95 words
A λ sensor comprising a metallic oxide semiconductor whose resistance value is varied by a gas, characterized in that the metallic oxide semiconductor is a compound ASnO 3- δ wherein A is at least one member selected from the group consisting of Ra, Ba, Sr and Ca, and δ is a non-stoichiometric parameter, the compound ASnO 3- δ having added thereto the dioxide of at least one element selected from the group consisting of silicon, germanium, zirconium and hafnium in an amount of 5 to 300 mmols per mol of the compound ASnO 3- δ.
Claim 3
Dependent Claim
32 words
A λ sensor as defined in claim 1 wherein the additive is silica and is used in an amount of 20 to 300 mmols per mol of the compound ASnO 3- δ.
Claim 4
Dependent Claim
27 words
A λ sensor as defined in claim 2 wherein the amount of the additive is 20 to 200 mmols per mol of the compound ASnO 3- δ.
Claim 5
Dependent Claim
28 words
A λ sensor as defined in any one of claims 1 to 3 wherein the compound ASnO 3- δ is 0.02 to 25 μ in mean crystallite size.
Claim 6
Dependent Claim
23 words
A λ sensor as defined in claim 4 wherein the compound ASnO 3- δ is 0.15 to 8 μ in mean crystallite size.
Claim 7
Dependent Claim
34 words
A λ sensor as defined in claim 5 wherein the element A of the compound ASnO 3- δ is at least one member selected from the group consisting of element Ba and element Ra.
Claim 8
Dependent Claim
33 words
A λ sensor as defined in claim 1 or 2 wherein the compound ASnO 3- δ has added thereto 20 μg to 3 mg of a noble metal per gram of the compound.
Claim 9
Dependent Claim
30 words
A λ sensor as defined in claim 7 wherein the noble metal is at least one member selected from the group consisting of Pt, Rh, Ir, Os, Ru and Pd.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-04-20 | 1990-10-20 | 1991-04-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-04-20 | 1994-10-20 | 1995-04-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-04-20 | 1998-10-20 | 1999-04-21 | $7700.00 | Window Closed / Lapsed |