US6311494B2
Expired / Lapsed
US
⏱️ 0.0 years remaining
Exhaust gas recirculation system for a turbocharged internal combustion engine
Assignee: Cummins Inc
•
Filing: 2001-01-31
•
Granted: 2001-11-06
•
Expires: 2021-01-31
Abstract
Abstract An exhaust gas recirculation (EGR) enhancement system for a turbocharged internal combustion engine includes a throttle valve arranged in the exhaust duct of the engine, downstream of the EGR system. The throttle valve is controlled in response to engine load and engine speed to selectively provide back pressure upstream of the throttle valve to selectively drive an EGR exhaust flow through an EGR duct to the intake manifold. An embodiment of the EGR system includes a cooler that lowers the temperature of the EGR exhaust flow to provide better reductions in nitric oxide emissions. The turbine is equipped to allow excess pressure to be released through a wastegate duct arranged in fluid parallel with the exhaust turbine, thereby allowing for higher power and higher speeds.
Inventors
- 👤 Thomas L. McKinley
- 👤 Philip M. Dimpelfeld
- 👤 John M. Mulloy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 02:28
CPC Classifications
F; F02; F02D; F02D41/00; F02D41/0025; F02D41/0047; F02D41/0065; F02B; F02B29/00; F02B29/04; F02B29/0406; F02D9/00; F02D9/04; F02M; F02M26/00; F02M26/02; F02M26/04; F02M26/05; F02M26/13; F02M26/22; F02M26/23; F02B37/00; F02B37/12; F02B37/18; F02B37/24; F02D9/06; F02M26/09; F02M26/10; F02M26/33; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12; Y02T10/40
Claims Analysis
Total Claims: 32
Claim 1
Independent Claim
161 words
An internal combustion engine having an intake duct, an exhaust duct, and an exhaust gas recirculation system comprising: an EGR duct connected in fluid communication with the exhaust duct for guiding an EGR flow of exhaust gas from the exhaust duct to the intake duct; an EGR cooler located in the EGR duct for cooling the EGR flow prior to entering the intake duct; an exhaust turbine in the exhaust duct downstream of said EGR duct, the turbine driving an intake compressor; a throttle valve arranged in the exhaust duct downstream of said EGR duct operable to selectably restrict flow through the exhaust duct; and a controller operable to adjust the throttle valve; a wastegate duct in communication with the exhaust duct for bypassing a wastegate flow from the exhaust duct upstream of the exhaust turbine to reenter the exhaust duct downstream of the turbine; and a wastegate valve located in the wastegate bypass duct for selectively restricting said wastegate flow.
Claim 2
Dependent Claim
161 words
An internal combustion engine having an intake duct, an exhaust duct, and an exhaust gas recirculation system comprising: an EGR duct connected in fluid communication with the exhaust duct for guiding an EGR flow of exhaust gas from the exhaust duct to the intake duct; an EGR cooler located in the EGR duct for cooling the EGR flow prior to entering the intake duct; an exhaust turbine in the exhaust duct downstream of said EGR duct, the turbine driving an intake compressor; a throttle valve arranged in the exhaust duct downstream of said EGR duct operable to selectably restrict flow through the exhaust duct; and a controller operable to adjust the throttle valve; a wastegate duct in communication with the exhaust duct for bypassing a wastegate flow from the exhaust duct upstream of the exhaust turbine to reenter the exhaust duct downstream of the turbine; and a wastegate valve located in the wastegate bypass duct for selectively restricting said wastegate flow.
Claim 3
Dependent Claim
18 words
The engine according to claim 1 , wherein the throttle valve is located downstream of the exhaust turbine.
Claim 4
Dependent Claim
30 words
The engine according to claim 2 , wherein the throttle valve is located downstream of a port from in which the wastegate flow exits the wastegate duct into the exhaust.
Claim 5
Dependent Claim
26 words
The engine according to claim 2 , wherein the throttle valve is located upstream of a port from in which the wastegate flow exits wastegate duct.
Claim 6
Dependent Claim
18 words
The engine according to claim 1 , wherein the throttle valve is located upstream of the exhaust turbine.
Claim 7
Dependent Claim
27 words
The engine according to claim 5 , wherein the throttle valve is located upstream of an inlet port into which the wastegate flow enters the wastegate duct.
Claim 8
Dependent Claim
27 words
The engine according to claim 5 , wherein the throttle valve is located downstream of an inlet port into which the wastegate flow enters the wastegate duct.
Claim 9
Dependent Claim
30 words
The engine according to claim 1 , wherein the controller adjusts the throttle valve to vary back pressure in the exhaust duct to control a rate of said EGR flow.
Claim 10
Dependent Claim
20 words
The engine according to claim 8 , wherein the controller modulates the throttle valve as a function of engine speed.
Claim 11
Dependent Claim
22 words
The engine according to claim 8 , wherein the controller substantially closes the throttle valve during a starting operation of the engine.
Claim 12
Dependent Claim
18 words
The engine according to claim 6 , wherein the turbine is of a type having fixed geometry vanes.
Claim 13
Dependent Claim
30 words
The engine according to claim 1 , wherein the controller is operable to substantially close the throttle valve to cause back pressure in the exhaust duct for providing compression braking.
Claim 14
Dependent Claim
23 words
The engine according to claim 1 , further comprising an EGR valve located in the EGR duct adjustable to vary the EGR flow.
Claim 15
Dependent Claim
22 words
The engine according to claim 1 , further comprising an intercooler located in the intake duct located upstream of the EGR duct.
Claim 16
Dependent Claim
186 words
An exhaust gas recirculation system for an internal combustion engine having an intake duct, an exhaust duct, and a turbocharger with a turbine located in the exhaust duct, the turbocharger driving a compressor located in the intake for charging air in the intake duct, the exhaust gas recirculation system comprising: an EGR duct connected in fluid communication with the exhaust duct upstream of the turbine for guiding an EGR flow of exhaust gas from the exhaust duct to the intake duct; an EGR cooler located in the EGR duct for cooling the EGR flow prior to entering the intake duct; a throttle valve arranged in the exhaust duct downstream of said EGR duct operable to selectably restrict flow through the exhaust duct; a controller operable to adjust the throttle valve for controlling back pressure in the exhaust duct; a wastegate duct in communication with the exhaust duct for bypassing a wastegate flow from the exhaust duct upstream of the exhaust turbine to reenter the exhaust duct downstream of the turbine; and a wastegate valve located in the wastegate bypass duct for selectively restricting said wastegate flow.
Claim 17
Dependent Claim
186 words
An exhaust gas recirculation system for an internal combustion engine having an intake duct, an exhaust duct, and a turbocharger with a turbine located in the exhaust duct, the turbocharger driving a compressor located in the intake for charging air in the intake duct, the exhaust gas recirculation system comprising: an EGR duct connected in fluid communication with the exhaust duct upstream of the turbine for guiding an EGR flow of exhaust gas from the exhaust duct to the intake duct; an EGR cooler located in the EGR duct for cooling the EGR flow prior to entering the intake duct; a throttle valve arranged in the exhaust duct downstream of said EGR duct operable to selectably restrict flow through the exhaust duct; a controller operable to adjust the throttle valve for controlling back pressure in the exhaust duct; a wastegate duct in communication with the exhaust duct for bypassing a wastegate flow from the exhaust duct upstream of the exhaust turbine to reenter the exhaust duct downstream of the turbine; and a wastegate valve located in the wastegate bypass duct for selectively restricting said wastegate flow.
Claim 18
Dependent Claim
21 words
The exhaust gas recirculation system according to claim 15 , wherein the throttle valve is located downstream of the exhaust turbine.
Claim 19
Dependent Claim
33 words
The exhaust gas recirculation system according to claim 16 , wherein the throttle valve is located downstream of a port from in which the wastegate flow exits the wastegate duct into the exhaust.
Claim 20
Dependent Claim
29 words
The exhaust gas recirculation system according to claim 16 , wherein the throttle valve is located upstream of a port from in which the wastegate flow exits wastegate duct.
Claim 21
Dependent Claim
21 words
The exhaust gas recirculation system according to claim 15 , wherein the throttle valve is located upstream of the exhaust turbine.
Claim 22
Dependent Claim
30 words
The exhaust gas recirculation system according to claim 19 , wherein the throttle valve is located upstream of an inlet port into which the wastegate flow enters the wastegate duct.
Claim 23
Dependent Claim
30 words
The exhaust gas recirculation system according to claim 19 , wherein the throttle valve is located downstream of an inlet port into which the wastegate flow enters the wastegate duct.
Claim 24
Dependent Claim
33 words
The exhaust gas recirculation system according to claim 15 , wherein the controller adjusts the throttle valve to increase back pressure in the exhaust duct for controlling a rate of said EGR flow.
Claim 25
Dependent Claim
27 words
The exhaust gas recirculation system according to claim 22 , wherein the controller modulates the throttle valve as a function of one or more engine operating parameters.
Claim 26
Dependent Claim
20 words
The exhaust gas recirculation system according to claim 23 , wherein one of said engine operating parameters is engine speed.
Claim 27
Dependent Claim
20 words
The exhaust gas recirculation system according to claim 23 , wherein one of said engine operating parameters is engine load.
Claim 28
Dependent Claim
28 words
The exhaust gas recirculation system according to claim 22 , wherein the controller is operable to substantially close the throttle valve during a starting operation of the engine.
Claim 29
Dependent Claim
19 words
The exhaust gas recirculation system according to claim 15 , wherein the turbine is of a fixed geometry turbine.
Claim 30
Dependent Claim
20 words
The exhaust gas recirculation system according to claim 15 , wherein said controller is operable to adjust the wastegate valve.
Claim 31
Dependent Claim
33 words
The exhaust gas recirculation system according to claim 15 , wherein the controller is operable to substantially close the throttle valve to cause back pressure in the exhaust duct for providing compression braking.
Claim 32
Dependent Claim
26 words
The exhaust gas recirculation system according to claim 15 , further comprising an EGR valve located in the EGR duct adjustable to vary the EGR flow.
References Cited (Backward Citations)
US4215550A
Cited
US4373498A
Cited
US4496291A
Cited
US4615172A
Cited
US4756285A
Cited
JPH0191325A
Cited
EP0531277A2
Cited
JPH0571426A
Cited
DE4231218C1
Cited
DE4312462A1
Cited
US5657630A
Cited
WO1994029587A1
Cited
US5813231A
Cited
US5564275A
Cited
WO1996018030A1
Cited
US5791146A
Cited
US5794445A
Cited
US6003316A
Cited
US5738126A
Cited
US5937650A
Cited
US6230682B1
Cited
US6062027A
Cited
US5927075A
Cited
US5937651A
Cited
US5806308A
Cited
US6035639A
Cited
US6244256B1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2004-11-05 | 2005-05-07 | 2005-11-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2008-11-05 | 2009-05-07 | 2009-11-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2012-11-05 | 2013-05-07 | 2013-11-06 | $7700.00 | Window Closed / Lapsed |