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US7377270B2 Expired / Lapsed US ⏱️ 0.0 years remaining

Exhaust gas recirculation in a homogeneous charge compression ignition engine

Assignee: Caterpillar Inc
•
Filing: 2006-10-23
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Granted: 2008-05-27
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Expires: 2026-10-23
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Abstract

Abstract A homogeneous charge compression ignition engine operates by injecting liquid fuel directly in a combustion chamber, and mixing the fuel with recirculated exhaust and fresh air through an auto ignition condition of the fuel. The engine includes at least one turbocharger for extracting energy from the engine exhaust and using that energy to boost intake pressure of recirculated exhaust gas and fresh air. Elevated proportions of exhaust gas recirculated to the engine are attained by throttling the fresh air inlet supply. These elevated exhaust gas recirculation rates allow the HCCI engine to be operated at higher speeds and loads rendering the HCCI engine a more viable alternative to a conventional diesel engine.

Inventors

  • 👤 Kevin P. Duffy
  • 👤 Andrew J. Kieser
  • 👤 Anthony Rodman
  • 👤 Michael P. Liechty
  • 👤 Carl-Anders Hergart
  • 👤 William L. Hardy

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 21:51
CPC Classifications
F; F02; F02B; F02B37/00; F02B37/004; F01; F01N; F01N13/00; F01N13/009; F01N13/0097; F01N13/08; F01N13/10; F01N13/107; F01N3/00; F01N3/02; F01N3/021; F01N3/023; F01N3/033; F01N3/035; F02B37/013; F02B37/02; F02B37/025; F02D; F02D41/00; F02D41/0025; F02D41/0047; F02D41/0065; F02D41/30; F02D41/3011; F02D41/3017; F02D41/3035; F02D9/00; F02D9/02; F02M; F02M26/00; F02M26/02; F02M26/08; F02M26/09; F02M26/10; F02M26/13; F02M26/35; F02M26/38; F02M26/42; F02M26/43; F01N2430/00; F01N2560/00; F01N2560/02; F01N2560/025; F01N2560/026; F01N2560/14; F02B2275/00; F02B2275/14; F02B29/00; F02B29/04; F02B29/0406; F02B29/0412; F02B29/0425; F02B29/045; F02B29/0468; F02D15/00; F02M26/04; F02M26/05; F02M26/06; F02M26/14; F02M26/15; F02M26/22; F02M26/23; F02M26/24; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12; Y02T10/40

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 98 words
A method of operating an engine, comprising the steps of: mixing high and low pressure exhaust from upstream and downstream, respectively, of a turbocharger via a venturi connection: supplying a mixture of exhaust and fresh air to a combustion chamber of the engine; injecting liquid fuel into the combustion chamber prior to an auto-ignition condition of the fuel; mixing the fuel with the exhaust/air mixture in the combustion chamber; compressing the fuel/air/exhaust mixture through an auto-ignition condition of the fuel; increasing a proportion of exhaust gas supplied to the combustion chamber by throttling a fresh air supply passage.
Claim 2
Independent Claim 98 words
A method of operating an engine, comprising the steps of: mixing high and low pressure exhaust from upstream and downstream, respectively, of a turbocharger via a venturi connection: supplying a mixture of exhaust and fresh air to a combustion chamber of the engine; injecting liquid fuel into the combustion chamber prior to an auto-ignition condition of the fuel; mixing the fuel with the exhaust/air mixture in the combustion chamber; compressing the fuel/air/exhaust mixture through an auto-ignition condition of the fuel; increasing a proportion of exhaust gas supplied to the combustion chamber by throttling a fresh air supply passage.
Claim 3
Dependent Claim 30 words
The method of claim 1 including a step of compressing a mixture of fresh air and low pressure exhaust in the turbocharger prior to mixing with the high pressure exhaust.
Claim 4
Dependent Claim 82 words
The method of claim 2 including trapping particles in the low pressure exhaust prior to mixing with fresh air; cooling the low pressure exhaust prior to mixing with fresh air; trapping particles in the high pressure exhaust prior to mixing with the mixture of low pressure exhaust and fresh air; cooling the high pressure exhaust prior to mixing with the mixture of low pressure exhaust and fresh air; and cooling the mixture of low pressure exhaust, high pressure exhaust and fresh air.
Claim 5
Dependent Claim 32 words
The method of claim 1 wherein the injecting step is performed in a shower head spray pattern that includes spray plumes at a plurality of angles with respect to an injector centerline.
Claim 6
Dependent Claim 19 words
The method of claim 1 wherein the injecting step is performed during a compression stroke of the combustion chamber.
Claim 7
Dependent Claim 24 words
The method of claim 1 including a step of adjusting a relative ratio of low to high pressure exhaust recirculated to the combustion chamber.
Claim 8
Dependent Claim 35 words
The method of claim 1 wherein the turbocharger is a first turbocharger; and channeling exhaust from the first turbocharger to a second turbocharger; the low pressure exhaust is from an outlet from the second turbocharger.
Claim 9
Dependent Claim 183 words
An engine comprising: an engine housing having at least one combustion chamber disposed therein; a fuel injector positioned for direct injection of liquid fuel into each combustion chamber; an exhaust passage extending between the engine housing and a turbocharger; a high pressure exhaust gas recirculation passage connected to the exhaust passage; at least one outlet from the turbocharger with a first branch connected to a low pressure exhaust gas recirculation passage, and a second branch connected to a tail pipe; a fresh air supply passage connected to the low pressure exhaust gas recirculation passage; a venturi connection fluidly connecting the low pressure exhaust gas recirculation passage with the high pressure exhaust gas recirculation passage; a throttle control valve positioned in the fresh air supply passage; and an engine controller configured to inject fuel prior to an auto-ignition of the fuel and then to compress a mixture of fuel with air and exhaust gas in the combustion chamber to the auto-ignition condition of the fuel, and configured increase a proportion of exhaust gas supplied to the combustion chamber by actuating the throttle control valve.
Claim 10
Dependent Claim 183 words
An engine comprising: an engine housing having at least one combustion chamber disposed therein; a fuel injector positioned for direct injection of liquid fuel into each combustion chamber; an exhaust passage extending between the engine housing and a turbocharger; a high pressure exhaust gas recirculation passage connected to the exhaust passage; at least one outlet from the turbocharger with a first branch connected to a low pressure exhaust gas recirculation passage, and a second branch connected to a tail pipe; a fresh air supply passage connected to the low pressure exhaust gas recirculation passage; a venturi connection fluidly connecting the low pressure exhaust gas recirculation passage with the high pressure exhaust gas recirculation passage; a throttle control valve positioned in the fresh air supply passage; and an engine controller configured to inject fuel prior to an auto-ignition of the fuel and then to compress a mixture of fuel with air and exhaust gas in the combustion chamber to the auto-ignition condition of the fuel, and configured increase a proportion of exhaust gas supplied to the combustion chamber by actuating the throttle control valve.
Claim 11
Dependent Claim 23 words
The engine of claim 8 wherein the turbocharger is a first turbocharger; and a second turbocharger arranged in series with the first turbocharger.
Claim 12
Dependent Claim 32 words
The engine of claim 9 wherein each of the low pressure and high pressure exhaust gas recirculation passages includes a respective particle trap; and a cooler positioned downstream from the venturi connection.
Claim 13
Dependent Claim 29 words
The engine of claim 8 wherein the fuel injector has a shower head nozzle with outlets oriented at a plurality of different angles with respect to an injector centerline.
Claim 14
Dependent Claim 33 words
The engine of claim 8 including a first control valve positioned in the low pressure exhaust gas recirculation passage; and a second control valve positioned in the high pressure exhaust gas recirculation passage.
Claim 15
Dependent Claim 42 words
The engine of claim 12 wherein the exhaust gas recirculation system includes a cooler positioned downstream from the venturi connection for cooling a mixture of exhaust from the low pressure exhaust gas recirculation passage and the high pressure exhaust gas recirculation passage.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2011-05-27 2011-11-26 2012-05-27 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2015-05-27 2015-11-26 2016-05-27 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2019-05-27 2019-11-26 2020-05-27 $7700.00 Window Closed / Lapsed

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