Patent US6588210B2 successfully refreshed from Google Patents.
US6588210B2
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US
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Method for measuring recirculated exhaust gas flow in a compression-ignition engine
Assignee: Detroit Diesel Corp
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Filing: 2001-12-06
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Granted: 2003-07-08
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Expires: 2021-12-06
Abstract
Abstract A system and method for measuring the flow rate of recirculated exhaust gas in a compression ignition engine including a plurality of engine sensors having outputs indicative of current engine conditions and a turbocharger. The system includes an exhaust gas recirculation (EGR) valve mounted in the exhaust pipe upstream of the turbocharger for diverting a selectable portion of the exhaust gas for recirculation and combination with the charge air, one or more sensors for sensing current conditions of the recirculated exhaust gas, including temperature and pressure, one or more sensors for sensing current conditions of the intake air, and control logic for determining the flow rate of the recirculated exhaust gas as a function of the sensed conditions. In one embodiment, the system includes an obstruction in the flow path of the recirculated exhaust gas and a differential pressure sensor for determining the pressure differential between a point upstream of the obstruction and a point downstream of the obstruction and control logic for determining the flow rate of the recirculated exhaust gas as a function of the current intake manifold pressure, the recirculated exhaust gas temperature, and the differential pressure drop across the obstruction.
Inventors
- 👤 Admir M. Kreso
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 12:05
CPC Classifications
F; F02; F02D; F02D41/00; F02D41/0025; F02D41/0047; F02D41/0065; F02D41/0072; F02B; F02B37/00; F02B37/12; F02B37/24; G; G01; G01F; G01F1/00; G01F1/05; G01F1/34; G01F1/36; G01F1/40; G01F1/42; F02D2041/0067; F02D2200/00; F02D2200/02; F02D2200/04; F02D2200/0406; F02D2200/0414; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12; Y02T10/40
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
139 words
A method for measuring the mass flow rate of recirculated exhaust gas in a vehicle having a compression-ignition engine, a plurality of engine sensors having outputs indicative of current engine conditions including an intake manifold pressure sensor, and a variable geometry turbocharger in which geometry is varied by a controllable actuator, the method comprising: sensing intake manifold pressure; controllably diverting a selected portion of exhaust gas for mixture with intake air; sensing temperature in a flow of the recirculated exhaust gas; obstructing the flow of the recirculated exhaust gas; sensing pressure of the recirculated exhaust gas downstream of the obstruction; sensing pressure of the recirculated exhaust gas upstream of the obstruction; and determining flow rate of the recirculated exhaust gas as a function of the intake manifold pressure, recirculated exhaust gas temperature, and differential pressure drop across the obstruction.
Claim 2
Independent Claim
139 words
A method for measuring the mass flow rate of recirculated exhaust gas in a vehicle having a compression-ignition engine, a plurality of engine sensors having outputs indicative of current engine conditions including an intake manifold pressure sensor, and a variable geometry turbocharger in which geometry is varied by a controllable actuator, the method comprising: sensing intake manifold pressure; controllably diverting a selected portion of exhaust gas for mixture with intake air; sensing temperature in a flow of the recirculated exhaust gas; obstructing the flow of the recirculated exhaust gas; sensing pressure of the recirculated exhaust gas downstream of the obstruction; sensing pressure of the recirculated exhaust gas upstream of the obstruction; and determining flow rate of the recirculated exhaust gas as a function of the intake manifold pressure, recirculated exhaust gas temperature, and differential pressure drop across the obstruction.
Claim 3
Dependent Claim
65 words
The method of claim 1 wherein the exhaust gas is recirculated through a pipe, and wherein the flow of the recirculated exhaust gas is obstructed by providing a thin plate obstructor mounted in the pipe in the path of the recirculated exhaust gas defining an orifice having a diameter of between about 40% and about 80% of the diameter of the recirculated exhaust gas pipe.
Claim 4
Dependent Claim
21 words
The method of claim 2 further including providing a sharp edge on the edge of the plate which defines the orifice.
Claim 5
Dependent Claim
35 words
The method of claim 3 further including bevelling the edge of the obstructor defining the orifice on the downstream side of the orifice at an angle of between about 30° and about 60° from horizontal.
Claim 6
Dependent Claim
28 words
The method of claim 4 including bevelling the edge of the obstructor defining the orifice on the downstream side of the orifice at an angle of about 45°.
Claim 7
Dependent Claim
51 words
The method of claim 2 wherein the flow of the recirculated exhaust gas is obstructed by providing a thin plate obstructor mounted in the pipe in the path of the recirculated exhaust gas defining an orifice having a diameter of about 60% of the diameter of the recirculated exhaust gas pipe.
Claim 8
Dependent Claim
91 words
The method of claim 1 wherein the flow rate of the recirculated exhaust gas is determined by determining the differential pressure drop across the obstruction according to the following relationship: Differential Pressure Drop, kPa= a * (Sensor Voltage)− b; determining recirculated exhaust gas density according to the following relationship: Density=(Intake Pressure,kpa)/(EGR Temperature, K * 0.2876); and determining recirculated exhaust flow rate according to the following relationship: EGR Flow Rate (kg/min)−(Density/Density Correction) c * d * (Differential Pressure Drop, kPa) e , where a, b, c, d, and e are calibratable constants.
Claim 9
Independent Claim
129 words
A method for measuring flow ratio of recirculated exhaust gas to charge air in a vehicle having a compression-ignition engine, a plurality of engine sensors having outputs indicative of current engine conditions, and a variable geometry turbocharger in which geometry is varied by a controllable actuator, the method comprising: diverting a selected portion of exhaust gas for mixture with intake air; sensing the temperature of the recirculated exhaust gas; sensing the temperature of the charge air; sensing the temperature of the mixture of charged air and recirculated exhaust gas; and determining the flow ratio of the recirculated exhaust gas as a function of the temperature of the charge air, the temperature of the recirculated exhaust gas, and the temperature of the mixture of charge air and recirculated exhaust gas.
Claim 10
Independent Claim
129 words
A method for measuring flow ratio of recirculated exhaust gas to charge air in a vehicle having a compression-ignition engine, a plurality of engine sensors having outputs indicative of current engine conditions, and a variable geometry turbocharger in which geometry is varied by a controllable actuator, the method comprising: diverting a selected portion of exhaust gas for mixture with intake air; sensing the temperature of the recirculated exhaust gas; sensing the temperature of the charge air; sensing the temperature of the mixture of charged air and recirculated exhaust gas; and determining the flow ratio of the recirculated exhaust gas as a function of the temperature of the charge air, the temperature of the recirculated exhaust gas, and the temperature of the mixture of charge air and recirculated exhaust gas.
Claim 11
Dependent Claim
46 words
The method for claim 8 wherein determining the flow ratio of the recirculated exhaust gas is based upon the relationship: EGR % = m . egr m . air - T mixture - T air T egr - T mixture . ( 6 )
Claim 12
Dependent Claim
165 words
An information recording medium for use in a control module that controls a compression-ignition engine including a plurality of engine sensors having outputs indicative of current engine conditions, an intake manifold pressure sensor, and a variable geometry turbocharger in which geometry is varied by a controllable actuator, the information recording medium recording a computer program that is readable and executable by the control module, the computer program comprising: sensing the intake manifold pressure; controllably diverting a selected portion of the exhaust gas from the engine exhaust line for mixture with intake air; sensing the temperature in the flow path of the recirculated exhaust gas; sensing the pressure of the recirculated exhaust gas downstream of an obstruction in the flow of the recirculated exhaust gas; sensing the pressure of the recirculated exhaust gas upstream of the obstruction; and determining flow rate of the recirculated exhaust gas as a function of the current intake manifold pressure, recirculated exhaust gas temperature, and differential pressure drop across the obstruction.
Claim 13
Dependent Claim
165 words
An information recording medium for use in a control module that controls a compression-ignition engine including a plurality of engine sensors having outputs indicative of current engine conditions, an intake manifold pressure sensor, and a variable geometry turbocharger in which geometry is varied by a controllable actuator, the information recording medium recording a computer program that is readable and executable by the control module, the computer program comprising: sensing the intake manifold pressure; controllably diverting a selected portion of the exhaust gas from the engine exhaust line for mixture with intake air; sensing the temperature in the flow path of the recirculated exhaust gas; sensing the pressure of the recirculated exhaust gas downstream of an obstruction in the flow of the recirculated exhaust gas; sensing the pressure of the recirculated exhaust gas upstream of the obstruction; and determining flow rate of the recirculated exhaust gas as a function of the current intake manifold pressure, recirculated exhaust gas temperature, and differential pressure drop across the obstruction.
Claim 14
Dependent Claim
99 words
The information recording medium of claim 10 wherein the computer program further comprises determining the flow rate of the recirculated exhaust gas by determining the differential pressure drop across the obstruction according to the following relationship: Differential Pressure Drop, kPa= a * (Sensor Voltage)− b; determining the recirculated exhaust gas density according to the following relationship: Density=(Intake Pressure,kpa)/(EGR Temperature, K * 0.2876); and determining the recirculated exhaust flow rate according to the following relationship: EGR Flow Rate (kg/min)−(Density/Density Correction) c * d * (Differential Pressure Drop, kPa) e , where a, b, c, d, and e are calibratable constants.
Claim 15
Dependent Claim
150 words
An information recording medium for use in a control module that controls a compression-ignition engine including a plurality of engine sensors having outputs indicative of current engine conditions, an intake manifold pressure sensor, and a variable geometry turbocharger in which geometry is varied by a controllable actuator, the information recording medium recording a computer program that is readable and executable by the control module, the computer program comprising: controllably diverting a selected portion of the exhaust gas for mixture with intake air; sensing the temperature of the recirculated exhaust gas; sensing the temperature of the charge air; sensing the temperature of the mixture of charged air and recirculated exhaust gas; and determining the flow ratio of the recirculated exhaust gas as a function of the temperature of the charge air, the temperature of the recirculated exhaust gas, and the temperature of the mixture of charge air and recirculated exhaust gas.
Claim 16
Dependent Claim
150 words
An information recording medium for use in a control module that controls a compression-ignition engine including a plurality of engine sensors having outputs indicative of current engine conditions, an intake manifold pressure sensor, and a variable geometry turbocharger in which geometry is varied by a controllable actuator, the information recording medium recording a computer program that is readable and executable by the control module, the computer program comprising: controllably diverting a selected portion of the exhaust gas for mixture with intake air; sensing the temperature of the recirculated exhaust gas; sensing the temperature of the charge air; sensing the temperature of the mixture of charged air and recirculated exhaust gas; and determining the flow ratio of the recirculated exhaust gas as a function of the temperature of the charge air, the temperature of the recirculated exhaust gas, and the temperature of the mixture of charge air and recirculated exhaust gas.
Claim 17
Dependent Claim
51 words
The information recording medium of claim 12 wherein the computer program further comprises determining the flow ratio of the recirculated exhaust gas based upon the relationship: EGR % = m . egr m . air - T mixture - T air T egr - T mixture ( 6 )
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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) | 2006-07-07 | 2007-01-06 | 2007-07-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2010-07-07 | 2011-01-06 | 2011-07-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2014-07-07 | 2015-01-06 | 2015-07-08 | $7700.00 | Window Closed / Lapsed |