US7189374B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Emissions control
Assignee: Johnson Matthey PLC
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Filing: 2000-06-07
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Granted: 2007-03-13
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Expires: 2020-06-07
Abstract
Abstract A diesel engine ( 1 ) has an exhaust system ( 4 ) and an oxidation catalyst ( 5 a ). Exhaust gas for recirculation is taken through an intake pipe ( 6 ) downstream of the catalyst, and preferably upstream of a filter ( 5 b ) for soot. The recirculated gases are passed through a cooler ( 7 ) upstream of the EGR valve ( 8 ). Good removal of soot and NO x is achieved even at low exhaust gas temperature.
Inventors
- 👤 Pelham Nigel Hawker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 14:46
CPC Classifications
F; F01; F01N; F01N13/00; F01N13/009; F01N13/0097; F01N3/00; F01N3/02; F01N3/021; F01N3/023; F01N3/0231; F01N3/033; F01N3/035; F02; F02M; F02M26/00; F02M26/13; F02M26/14; F02M26/15; F02M26/22; F02M26/23; F02M26/27; F02M26/28; F02M26/02; F02M26/04; F02M26/06; F02M26/09; F02M26/10
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
73 words
A diesel engine having an intake and comprising an exhaust system, which exhaust system comprises an oxidation catalyst; a particulate trap; and an exhaust gas recirculation (EGR) system comprising an EGR system intake for taking a portion of an exhaust gas stream and passing it to the engine intake, wherein the EGR system intake is located downstream of the oxidation catalyst and the particulate trap is located downstream of the EGR system intake.
Claim 2
Dependent Claim
73 words
A diesel engine having an intake and comprising an exhaust system, which exhaust system comprises an oxidation catalyst; a particulate trap; and an exhaust gas recirculation (EGR) system comprising an EGR system intake for taking a portion of an exhaust gas stream and passing it to the engine intake, wherein the EGR system intake is located downstream of the oxidation catalyst and the particulate trap is located downstream of the EGR system intake.
Claim 3
Dependent Claim
34 words
An engine according to claim 1 , wherein the exhaust system is configured for taking a remaining portion of the exhaust gas that does not pass to the engine intake through the particulate trap.
Claim 4
Dependent Claim
17 words
An engine according to claim 1 , wherein the particulate trap is mounted in the EGR system.
Claim 5
Dependent Claim
23 words
An engine according to claim 1 , wherein a recirculation ratio of the EGR system is varied from 5 to 30% by volume.
Claim 6
Dependent Claim
44 words
An engine according to claim 1 further comprising an EGR valve located downstream of the EGR system intake; and a cooler for cooling gases to be recirculated in the EGR system, the cooler being mounted between the EGR system intake and the EGR valve.
Claim 7
Dependent Claim
94 words
A process for the reduction of polluting emissions from diesel engine exhaust gas, which includes NO x , comprising passing the engine exhaust gas over an oxidation catalyst to generate NO 2 from NO in the gas; recycling a portion of the gas that passed through the oxidation catalyst to an engine intake; and trapping particulates in a filter mounted downstream of where the portion of the exhaust gas is recycled; and oxidising the particulates trapped in the filter by reaction with at least some of the NO 2 generated in said passing step.
Claim 8
Dependent Claim
94 words
A process for the reduction of polluting emissions from diesel engine exhaust gas, which includes NO x , comprising passing the engine exhaust gas over an oxidation catalyst to generate NO 2 from NO in the gas; recycling a portion of the gas that passed through the oxidation catalyst to an engine intake; and trapping particulates in a filter mounted downstream of where the portion of the exhaust gas is recycled; and oxidising the particulates trapped in the filter by reaction with at least some of the NO 2 generated in said passing step.
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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) | 2010-03-12 | 2010-09-11 | 2011-03-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2014-03-12 | 2014-09-11 | 2015-03-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2018-03-12 | 2018-09-11 | 2019-03-13 | $7700.00 | Window Closed / Lapsed |