US6244256B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
High-temperature coolant loop for cooled exhaust gas recirculation for internal combustion engines
Assignee: Mahle Behr GmbH and Co KG
•
Filing: 1999-10-07
•
Granted: 2001-06-12
•
Expires: 2019-10-07
Abstract
Abstract An EGR system for an internal combustion engine has a separate, secondary high-temperature cooling loop, in addition to a primary cooling loop. In the secondary cooling loop, coolant flows through a secondary high-temperature exhaust gas cooler, which is located upstream of the primary exhaust gas cooler. A large amount of heat is transferred from the exhaust gases to the coolant in the secondary high-temperature cooling loop. The heat absorbed by the high-temperature coolant is rejected in a secondary high-temperature radiator. Heat absorbed by the primary coolant is rejected in a primary radiator. The two radiators occupy the same amount of frontal area as a single radiator used in a conventional single-stage EGR cooling system, but overall reject more heat to the ambient. In an alternate arrangement, the EGR system for a liquid-cooled internal combustion engine has a single exhaust gas cooler which is cooled by an EGR cooling loop that is independent of the engine cooling system. The EGR cooling loop includes a secondary radiator located adjacent the primary engine cooling radiator, and the two radiators together occupy the same frontal area as a single radiator used in a conventional single-stage EGR cooling system, but overall reject more heat to the ambient.
Inventors
- 👤 John C. Wall
- 👤 Markus Flik
- 👤 Hans Lange
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 08:41
CPC Classifications
F; F02; F02B; F02B29/00; F02B29/04; F02B29/0406; F02B29/0425; F02M; F02M26/00; F02M26/13; F02M26/22; F02M26/23; F02M26/28; F02M26/02; F02M26/04; F02M26/05; F02M26/14; F02M26/16; F02M26/24; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12
Claims Analysis
Total Claims: 32
Claim 1
Independent Claim
109 words
An exhaust gas cooling system for cooling exhaust gas in the exhaust gas recirculation system of an internal combustion engine prior to admixing with charge air for the engine, the exhaust gas cooling system comprising: a primary cooling loop including: a primary radiator; and a primary pump that circulates coolant through the primary cooling loop to the primary radiator; and a secondary cooling loop including: secondary radiator; a secondary exhaust gas cooler in fluid communication with the secondary radiator; and a secondary pump that circulates coolant through the secondary cooling loop from the secondary exhaust gas cooler to the secondary radiator and back to the secondary exhaust gas cooler.
Claim 2
Dependent Claim
109 words
An exhaust gas cooling system for cooling exhaust gas in the exhaust gas recirculation system of an internal combustion engine prior to admixing with charge air for the engine, the exhaust gas cooling system comprising: a primary cooling loop including: a primary radiator; and a primary pump that circulates coolant through the primary cooling loop to the primary radiator; and a secondary cooling loop including: secondary radiator; a secondary exhaust gas cooler in fluid communication with the secondary radiator; and a secondary pump that circulates coolant through the secondary cooling loop from the secondary exhaust gas cooler to the secondary radiator and back to the secondary exhaust gas cooler.
Claim 3
Dependent Claim
96 words
A cooling system as claimed in claim 1 , wherein the engine is liquid-cooled, and the primary cooling loop is part of the engine cooling system, and further comprising a primary exhaust gas cooler in fluid communication with the primary radiator such that the primary pump that circulates coolant through the primary cooling loop from the primary exhaust gas cooler to the primary radiator and back to the primary exhaust gas cooler, and wherein recirculating exhaust gas is cooled first in the secondary exhaust gas cooler, and then is cooled in the primary exhaust gas cooler.
Claim 4
Dependent Claim
21 words
A cooling system as claimed in claim 2 , wherein the primary radiator is the radiator of the engine cooling system.
Claim 5
Dependent Claim
22 words
A cooling system as claimed in claim 3 , wherein the secondary radiator has a smaller frontal area than the primary radiator.
Claim 6
Dependent Claim
22 words
A cooling system as claimed in claim 1 , wherein the secondary radiator has a smaller frontal area than the primary radiator.
Claim 7
Dependent Claim
16 words
A cooling system as claimed in claim 5 , wherein the engine is a diesel engine.
Claim 8
Dependent Claim
43 words
A cooling system as claimed in claim 1 , further comprising a turbocharge-air cooling circuit, comprising a charge-air cooler and a compressor for compressing ambient air and circulating compressed charge air to the charge-air cooler and from the charge-air cooler to the engine.
Claim 9
Dependent Claim
22 words
A cooling system as claimed in claim 7 , further comprising a turbine driven by exhaust gas, which turbine drives the compressor.
Claim 10
Dependent Claim
51 words
A cooling system as claimed in claim 7 , wherein the charge-air cooler is positioned in front of the primary and secondary radiators, in a direction of forward vehicle travel, and defines a cooling area that is equal to the sum of cooling areas defined by the primary and secondary radiators.
Claim 11
Dependent Claim
148 words
In an exhaust gas recirculation system for an internal combustion engine, the system comprising an EGR valve for controlling the flow of exhaust gas diverted from the engine exhaust gas stream and recirculated to the engine intake, and a primary cooling loop including a primary exhaust gas cooler located downstream of the EGR valve in the direction of recirculated exhaust gas flow, a primary radiator and a primary pump for circulating coolant through the primary cooling loop, the improvement comprising: a secondary cooling loop comprising: a secondary exhaust gas cooler located upstream of the primary exhaust gas cooler in the direction of recirculated exhaust gas flow; a secondary radiator having a smaller frontal area than the primary radiator; and a secondary pump for circulating coolant through the secondary cooling loop from the secondary exhaust gas cooler to the secondary radiator and back to the secondary exhaust gas cooler.
Claim 12
Dependent Claim
148 words
In an exhaust gas recirculation system for an internal combustion engine, the system comprising an EGR valve for controlling the flow of exhaust gas diverted from the engine exhaust gas stream and recirculated to the engine intake, and a primary cooling loop including a primary exhaust gas cooler located downstream of the EGR valve in the direction of recirculated exhaust gas flow, a primary radiator and a primary pump for circulating coolant through the primary cooling loop, the improvement comprising: a secondary cooling loop comprising: a secondary exhaust gas cooler located upstream of the primary exhaust gas cooler in the direction of recirculated exhaust gas flow; a secondary radiator having a smaller frontal area than the primary radiator; and a secondary pump for circulating coolant through the secondary cooling loop from the secondary exhaust gas cooler to the secondary radiator and back to the secondary exhaust gas cooler.
Claim 13
Dependent Claim
28 words
An exhaust gas recirculation system as claimed in claim 10 , wherein the engine is liquid-cooled, and the primary cooling loop is part of the engine cooling system.
Claim 14
Dependent Claim
23 words
An exhaust gas recirculation system as claimed in claim 11 , wherein the primary radiator is the radiator of the engine cooling system.
Claim 15
Dependent Claim
145 words
In an internal combustion engine having an exhaust gas recirculation system comprising an EGR valve for controlling the flow of exhaust gas diverted from the engine exhaust gas stream and recirculated to the engine intake, a primary cooling loop including a primary exhaust gas cooler located downstream of the EGR valve in the direction of recirculated exhaust gas flow, a primary radiator and a primary pump for circulating coolant through the primary cooling loop, the improvement comprising: a secondary cooling loop comprising: a secondary exhaust gas cooler located upstream of the primary exhaust gas cooler in the direction of recirculated exhaust gas flow; a secondary radiator having a smaller frontal area than the primary radiator; and a secondary pump for circulating coolant through the secondary cooling loop from the secondary exhaust gas cooler to the secondary radiator and back to the secondary exhaust gas cooler.
Claim 16
Dependent Claim
145 words
In an internal combustion engine having an exhaust gas recirculation system comprising an EGR valve for controlling the flow of exhaust gas diverted from the engine exhaust gas stream and recirculated to the engine intake, a primary cooling loop including a primary exhaust gas cooler located downstream of the EGR valve in the direction of recirculated exhaust gas flow, a primary radiator and a primary pump for circulating coolant through the primary cooling loop, the improvement comprising: a secondary cooling loop comprising: a secondary exhaust gas cooler located upstream of the primary exhaust gas cooler in the direction of recirculated exhaust gas flow; a secondary radiator having a smaller frontal area than the primary radiator; and a secondary pump for circulating coolant through the secondary cooling loop from the secondary exhaust gas cooler to the secondary radiator and back to the secondary exhaust gas cooler.
Claim 17
Dependent Claim
27 words
An internal combustion engine as claimed in claim 13 , wherein the engine is liquid-cooled, and the primary cooling loop is part of the engine cooling system.
Claim 18
Dependent Claim
22 words
An internal combustion engine as claimed in claim 14 , wherein the primary radiator is the radiator of the engine cooling system.
Claim 19
Dependent Claim
174 words
In a motor vehicle having an internal combustion engine with an exhaust gas recirculation system for the engine, the system comprising an EGR valve for controlling the flow of exhaust gas diverted from the engine exhaust gas stream and recirculated to the engine intake, and a primary cooling loop including a primary exhaust gas cooler located downstream of the EGR valve in the direction of recirculated exhaust gas flow, a primary radiator at the front of the vehicle, and a primary pump for circulating coolant through the primary cooling loop, the improvement comprising: a secondary cooling loop for the exhaust gas recirculation system comprising: a secondary exhaust gas cooler located upstream of the primary exhaust gas cooler in the direction of recirculated exhaust gas flow; a secondary radiator adjacent the primary radiator, the secondary radiator having a smaller frontal area than the primary radiator; and a secondary pump for circulating coolant through the secondary cooling loop from the secondary exhaust gas cooler to the secondary radiator and back to the secondary exhaust gas cooler.
Claim 20
Dependent Claim
174 words
In a motor vehicle having an internal combustion engine with an exhaust gas recirculation system for the engine, the system comprising an EGR valve for controlling the flow of exhaust gas diverted from the engine exhaust gas stream and recirculated to the engine intake, and a primary cooling loop including a primary exhaust gas cooler located downstream of the EGR valve in the direction of recirculated exhaust gas flow, a primary radiator at the front of the vehicle, and a primary pump for circulating coolant through the primary cooling loop, the improvement comprising: a secondary cooling loop for the exhaust gas recirculation system comprising: a secondary exhaust gas cooler located upstream of the primary exhaust gas cooler in the direction of recirculated exhaust gas flow; a secondary radiator adjacent the primary radiator, the secondary radiator having a smaller frontal area than the primary radiator; and a secondary pump for circulating coolant through the secondary cooling loop from the secondary exhaust gas cooler to the secondary radiator and back to the secondary exhaust gas cooler.
Claim 21
Dependent Claim
26 words
A motor vehicle as claimed in claim 16 , wherein the engine is liquid-cooled, and the primary cooling loop is part of the engine cooling system.
Claim 22
Dependent Claim
21 words
A motor vehicle as claimed in claim 17 , wherein the primary radiator is the radiator of the engine cooling system.
Claim 23
Dependent Claim
16 words
A motor vehicle as claimed in claim 18 , wherein the engine is a diesel engine.
Claim 24
Dependent Claim
30 words
A motor vehicle as claimed in claim 18 , wherein the primary radiator and the secondary radiator together occupy the entire frontal area of the vehicle available for radiator cooling.
Claim 25
Dependent Claim
30 words
A motor vehicle as claimed in claim 16 , wherein the primary radiator and the secondary radiator together occupy the entire frontal area of the vehicle available for radiator cooling.
Claim 26
Dependent Claim
137 words
In a motor vehicle having a liquid-cooled internal combustion engine comprising: an engine cooling system having an engine cooling loop including a primary radiator at the front of the vehicle, and an exhaust gas recirculation system having an EGR valve for controlling the flow of exhaust gas diverted from the engine exhaust gas stream and recirculated to the engine intake, and an exhaust gas cooler located downstream of the EGR valve in the direction of recirculated exhaust gas flow, the improvement comprising: an EGR cooling loop for the exhaust gas cooler which is independent of the engine cooling loop and comprises: a secondary radiator adjacent the primary radiator; and an EGR coolant pump for circulating coolant through the EGR cooling loop from the exhaust gas cooler to the secondary radiator and back to the exhaust gas cooler.
Claim 27
Dependent Claim
137 words
In a motor vehicle having a liquid-cooled internal combustion engine comprising: an engine cooling system having an engine cooling loop including a primary radiator at the front of the vehicle, and an exhaust gas recirculation system having an EGR valve for controlling the flow of exhaust gas diverted from the engine exhaust gas stream and recirculated to the engine intake, and an exhaust gas cooler located downstream of the EGR valve in the direction of recirculated exhaust gas flow, the improvement comprising: an EGR cooling loop for the exhaust gas cooler which is independent of the engine cooling loop and comprises: a secondary radiator adjacent the primary radiator; and an EGR coolant pump for circulating coolant through the EGR cooling loop from the exhaust gas cooler to the secondary radiator and back to the exhaust gas cooler.
Claim 28
Dependent Claim
16 words
A motor vehicle as claimed in claim 22 , wherein the engine is a diesel engine.
Claim 29
Dependent Claim
30 words
A motor vehicle as claimed in claim 22 , wherein the primary radiator and the secondary radiator together occupy the entire frontal area of the vehicle available for radiator cooling.
Claim 30
Dependent Claim
127 words
In a liquid-cooled internal combustion engine comprising: an engine cooling system having an engine cooling loop including a primary radiator, and an exhaust gas recirculation system having an EGR valve for controlling the flow of exhaust gas diverted from the engine exhaust gas stream and recirculated to the engine intake, and an exhaust gas cooler located downstream of the EGR valve in the direction of recirculated exhaust gas flow, the improvement comprising: an EGR cooling loop for the exhaust gas cooler which is independent of the engine cooling loop and comprises: a secondary radiator adjacent the primary radiator; and an EGR coolant pump for circulating coolant through the EGR cooling loop from the exhaust gas cooler to the secondary radiator and back to the exhaust gas cooler.
Claim 31
Dependent Claim
127 words
In a liquid-cooled internal combustion engine comprising: an engine cooling system having an engine cooling loop including a primary radiator, and an exhaust gas recirculation system having an EGR valve for controlling the flow of exhaust gas diverted from the engine exhaust gas stream and recirculated to the engine intake, and an exhaust gas cooler located downstream of the EGR valve in the direction of recirculated exhaust gas flow, the improvement comprising: an EGR cooling loop for the exhaust gas cooler which is independent of the engine cooling loop and comprises: a secondary radiator adjacent the primary radiator; and an EGR coolant pump for circulating coolant through the EGR cooling loop from the exhaust gas cooler to the secondary radiator and back to the exhaust gas cooler.
Claim 32
Dependent Claim
15 words
An engine as claimed in claim 25 , wherein the engine is a diesel engine.
References Cited (Backward Citations)
US3918412A
Cited
US4003969A
Cited
US4393853A
Cited
US4561387A
Cited
US4885911A
Cited
US4961404A
Cited
US5394854A
Cited
US5163295A
Cited
US5353757A
Cited
US5607010A
Cited
US5611202A
Cited
US5440880A
Cited
US5533487A
Cited
US5791146A
Cited
US5794445A
Cited
US5711154A
Cited
US5690082A
Cited
US5740786A
Cited
US5732688A
Cited
US5802846A
Cited
US5927075A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2004-06-11 | 2004-12-11 | 2005-06-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2008-06-11 | 2008-12-11 | 2009-06-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2012-06-11 | 2012-12-11 | 2013-06-12 | $7700.00 | Window Closed / Lapsed |