US4253302A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Exhaust gas purifying device for internal combustion engine
Assignee: Soken Inc
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Filing: 1978-07-05
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Granted: 1981-03-03
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Expires: 1998-07-05
Abstract
Abstract An oxygen sensor is disposed upstream of a three-way catalyst in an exhaust system of an internal combustion engine and includes a sensing element of metal oxide whose electromotive force or resistance value varies in response to the concentration of oxygen in the engine exhaust gases. A catalytic body including a catalytic metal material exhibiting the same catalytic performance as that of the three-way catalyst is disposed around the sensing element or upstream of the oxygen sensor or is formed by impregnating a portion of the sensing element with the catalytic metal material, so that the air-fuel ratio at the intake side or exhaust side of the engine can be controlled depending on the output of the oxygen sensor.
Inventors
- 👤 Mitsuru Asano
- 👤 Yoshihiro Segawa
- 👤 Kenji Kondo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 06:51
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/26; G01N27/403; G01N27/406; G01N27/407; F; F01; F01N; F01N3/00; F01N3/08; F01N3/10; F01N3/18; F01N3/22; F01N3/222; F02; F02B; F02B75/00; F02B75/02; F02B2075/022; F02B2075/027; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
124 words
An exhaust gas purifying device for an internal combustion engine comprising a three-way catalyst disposed in the exhaust system of the engine, an oxygen sensor disposed upstream of said three-way catalyst in said exhaust system and including a sensing element generating an output signal varying in response to the concentration of oxygen in the engine exhaust gases, and means for controlling the air-fuel ratio at the intake side or exhaust side of the engine depending on the output signal of said oxygen sensor, wherein the improvement comprises another three-way catalyst disposed in the vicinity of said sensing element to produce around said sensing element an exhaust gas atmosphere which is substantially the same as the atmosphere in which said three-way catalyst is actually operating.
Claim 2
Dependent Claim
124 words
An exhaust gas purifying device for an internal combustion engine comprising a three-way catalyst disposed in the exhaust system of the engine, an oxygen sensor disposed upstream of said three-way catalyst in said exhaust system and including a sensing element generating an output signal varying in response to the concentration of oxygen in the engine exhaust gases, and means for controlling the air-fuel ratio at the intake side or exhaust side of the engine depending on the output signal of said oxygen sensor, wherein the improvement comprises another three-way catalyst disposed in the vicinity of said sensing element to produce around said sensing element an exhaust gas atmosphere which is substantially the same as the atmosphere in which said three-way catalyst is actually operating.
Claim 3
Dependent Claim
21 words
An exhaust gas purifying device as claimed in claim 1, wherein said another three-way catalyst is disposed around said sensing element.
Claim 4
Dependent Claim
26 words
An exhaust gas purifying device as claimed in claim 1, wherein said another three-way catalyst is disposed upstream of said sensing element in said exhaust system.
Claim 5
Dependent Claim
29 words
An exhaust gas purifying device as claimed in claim 1, wherein said another three-way catalyst is formed by impregnating a portion of said sensing element with a catalytic material.
Claim 6
Dependent Claim
27 words
An exhaust gas purifying device as claimed in claim 1 or 2, wherein said another three-way catalyst is substantially the same as that of said three-way catalyst.
Claim 7
Dependent Claim
19 words
An exhaust gas purifying device as claimed in claim 1 or 2, wherein both said three-way catalysts include Pt-Rh.
Claim 8
Dependent Claim
21 words
An exhaust gas purifying device as claimed in claim 1 or 2, wherein both said three-way catalysts include Pt-Rh-CeO 2 .
Claim 9
Dependent Claim
30 words
An exhaust gas purifying device as claimed in claim 1 or 2, further including means for carrying said another three-way catalyst, said carrying means being permeable to engine exhaust gases.
Claim 10
Dependent Claim
18 words
An exhaust gas purifying device as claimed in claim 8, wherein said carrier means is a foamed ceramic.
Claim 11
Dependent Claim
18 words
An exhaust gas purifying device as claimed in claim 8, wherein said carrier means is a silica cloth.
Claim 12
Dependent Claim
117 words
An exhaust gas purifying device for an internal combustion engine comprising a three-way catalyst disposed in the exhaust system of the engine, an oxygen sensor disposed upstream of said three-way catalyst in said exhaust system and including a sensing element generating an output signal varying in response to the concentration of oxygen in the engine exhaust gases, and means for controlling the air-fuel ratio at the intake side or exhaust side of the engine depending on the output signal of said oxygen sensor, wherein the improvement comprises another three-way catalyst in the vicinity of said sensing element to produce around said sensing element an exhaust gas atmosphere substantially the same as that produced by said three-way catalyst.
Claim 13
Dependent Claim
117 words
An exhaust gas purifying device for an internal combustion engine comprising a three-way catalyst disposed in the exhaust system of the engine, an oxygen sensor disposed upstream of said three-way catalyst in said exhaust system and including a sensing element generating an output signal varying in response to the concentration of oxygen in the engine exhaust gases, and means for controlling the air-fuel ratio at the intake side or exhaust side of the engine depending on the output signal of said oxygen sensor, wherein the improvement comprises another three-way catalyst in the vicinity of said sensing element to produce around said sensing element an exhaust gas atmosphere substantially the same as that produced by said three-way catalyst.
Claim 14
Dependent Claim
35 words
An exhaust gas purifying device as claimed in claim 11, wherein said another three-way catalyst is formed by impregnating a portion of said sensing element serving as said catalyst carrier means with a catalytic material.
Claim 15
Dependent Claim
24 words
An exhaust gas purifying device as claimed in claim 11 or 12, wherein said another three-way catalyst is the same as said three-way catalyst.
Claim 16
Dependent Claim
19 words
An exhaust gas purifying device as claimed in claim 11 or 12, wherein both said three-way catalysts include Pt-Rh.
Claim 17
Dependent Claim
21 words
An exhaust gas purifying device as claimed in claim 11 or 12 wherein both said three catalysts include Pt-Rh-CeO 2 .
Claim 18
Dependent Claim
27 words
An exhaust gas purifying device as claimed in claim 11 or 12 wherein said catalyst carrier means is made of material permeable to the engine exhaust gases.
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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) | 1984-03-02 | 1984-09-01 | 1985-03-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-03-02 | 1988-09-01 | 1989-03-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-03-02 | 1992-09-01 | 1993-03-03 | $7700.00 | Window Closed / Lapsed |