US6295809B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Emission control system with a catalyst
Assignee: Ford Global Technologies LLC
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Filing: 1999-07-12
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Granted: 2001-10-02
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Expires: 2019-07-12
Abstract
Abstract A reductant injection control strategy for controlling an amount of nitrogen oxide reducing agent injected upstream of a selective reduction catalyst uses an ammonia sensor located downstream of the catalyst. An open loop injection quantity is first determined based on operation conditions. Ammonia concentration detected downstream of the catalyst is controlled to a desired value, with the desired value based on catalyst temperature and the open loop injection quantity.
Inventors
- 👤 Robert Henry Hammerle
- 👤 Karen Marie Adams
- 👤 Paul Matthew Laing
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 23:57
CPC Classifications
F; F01; F01N; F01N3/00; F01N3/08; F01N3/10; F01N3/18; F01N3/20; F01N3/206; F01N3/208; B; B01; B01D; B01D53/00; B01D53/34; B01D53/92; B01D53/94; B01D53/9404; B01D53/9409; B01D53/9431; B01D53/9495; F01N2560/00; F01N2560/02; F01N2560/021; F01N2560/06; F01N2610/00; F01N2610/02; F01N2610/14; F01N2610/1453; F01N2610/146; F01N2900/00; F01N2900/06; F01N2900/08; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
111 words
A method for controlling a reductant injection into a catalyst coupled to an internal combustion engine, the method comprising: determining a temperature region in which the catalyst is operating; generating a reductant injection quantity based on engine operating conditions; generating a desired reductant slip based on a catalyst temperature and said reductant injection quantity; and adjusting said reductant injection quantity so that an actual reductant slip approaches said desired reductant slip, wherein adjusting said reductant injection quantity further comprises determining said actual reductant slip based on a sensor located downstream of the catalyst, and decreasing said reductant infection quantity when said actual reductant slip is greater than said desired reductant slip.
Claim 2
Independent Claim
111 words
A method for controlling a reductant injection into a catalyst coupled to an internal combustion engine, the method comprising: determining a temperature region in which the catalyst is operating; generating a reductant injection quantity based on engine operating conditions; generating a desired reductant slip based on a catalyst temperature and said reductant injection quantity; and adjusting said reductant injection quantity so that an actual reductant slip approaches said desired reductant slip, wherein adjusting said reductant injection quantity further comprises determining said actual reductant slip based on a sensor located downstream of the catalyst, and decreasing said reductant infection quantity when said actual reductant slip is greater than said desired reductant slip.
Claim 3
Dependent Claim
14 words
The method recited in claim 3 wherein the reductant is any ammonia generating material.
Claim 4
Dependent Claim
35 words
The method recited in claim 3 wherein said step of generating said desired value of reductant slip further comprises generating said desired value of reductant slip based on a fraction of said reductant injection quantity.
Claim 5
Dependent Claim
25 words
The method recited in claim 3 further comprising the step of generating said desired value of reductant slip based on Nox generated by the engine.
Claim 6
Dependent Claim
15 words
The method recited in claim 3 wherein said fraction is based on said catalyst temperature.
Claim 7
Dependent Claim
40 words
The method recited in claim 3 wherein said step of generating said reductant injection quantity further comprises the step of generating said reductant injection quantity based on a catalyst temperature and a fraction of an engine out nitrogen oxide production.
Claim 8
Dependent Claim
25 words
The method recited in claim 3 further comprising the step of discontinuing said adjustment step based on whether said catalyst temperature is within temperature limits.
Claim 9
Dependent Claim
18 words
The method recited in claim 7 wherein said step temperature limits are based on exhaust gas space velocity.
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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) | 2004-10-01 | 2005-04-02 | 2005-10-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2008-10-01 | 2009-04-02 | 2009-10-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2012-10-01 | 2013-04-02 | 2013-10-02 | $7700.00 | Window Closed / Lapsed |