Engine cylinder deactivation to improve the performance of exhaust emission control systems

• US 6,904,752 B2
• Filed: 11/25/2002
• Issued: 06/14/2005
• Est. Priority Date: 11/30/2001
• Status: Expired due to Term

• Current Assignee: Delphi Technologies Ip Limited (BorgWarner Incorporated)
• Original Assignee: Delphi Technologies, Inc. (BorgWarner Incorporated)
• Inventors: Price, Kenneth S., Foster, Michael Ralph, Foster, Matthew G.
• Primary Examiner(s): Denion, Thomas
• Assistant Examiner(s): TRAN, DIEM T
• Application Number:
  US10/304,119
• Publication Number:
  US 20030121249A1
• Time in Patent Office: 932 Days
• Field of Search: 602/74, 602/85, 602/95, 602/99, 603/01, 603/11, 123/198.F, 123/481
• US Class Current: 60/295
• CPC Class Codes: B60H 1/00314 Arrangements permitting a rapid heating of the heating liquid B60H1/00492, B60H1/03 take precedence; aiding engine start by heating of engine coolants F02N19/10
• CPC Class Codes: B60H 1/00764 the input being a vehicle driving condition, e.g. speed B60H1/00828, B60H1/00864 take precedence
• CPC Class Codes: B60H 1/08 from other radiator than main radiator
• CPC Class Codes: B60H 1/12 using an air blower
• CPC Class Codes: F01L 13/0005 Deactivating valves
• CPC Class Codes: F01N 13/0097 the purifying devices are arranged in a single housing
• CPC Class Codes: F01N 3/023 using means for regenerating the filters, e.g. by burning trapped particles by electrically controlling the supply of combustible mixture or its constituents only F02D41/0235
• CPC Class Codes: F01N 3/0814 combined with catalytic converters, e.g. NOx absorption/storage reduction catalysts
• CPC Class Codes: F01N 3/0821 combined with particulate filters catalysed diesel particulate filters F01N3/035
• CPC Class Codes: F01N 3/0842 Nitrogen oxides
• CPC Class Codes: F01N 3/0885 Regeneration of deteriorated absorbents or adsorbents, e.g. desulfurization of NOx traps
• CPC Class Codes: F01N 9/005 using models instead of sensors to determine operating characteristics of exhaust systems, e.g. calculating catalyst temperature instead of measuring it directly
• CPC Class Codes: F01P 2037/02 starting
• CPC Class Codes: F01P 2060/08 Cabin heater
• CPC Class Codes: F02B 1/12 with compression ignition with fuel-air charge ignited by compression ignition of an additional fuel F02B7/00
• CPC Class Codes: F02B 2075/125 Direct injection in the combustion chamber for spark ignition engines, i.e. not in pre-combustion chamber
• CPC Class Codes: F02D 2250/36 Control for minimising NOx emissions
• CPC Class Codes: F02D 41/0087 Selective cylinder activation, i.e. partial cylinder operation deceleration cut-off F02D41/123
• CPC Class Codes: F02D 41/024 to increase temperature of the exhaust gas treating apparatus
• CPC Class Codes: F02D 41/0275 the exhaust gas treating apparatus being a NOx trap or adsorbent
• CPC Class Codes: Y02T 10/12 : Improving ICE efficiencies
• CPC Class Codes: Y02T 10/40 : Engine management systems

Abstract

The invention provides a controller and cylinder deactivation system to regenerate an exhaust aftertreatment device for a multicylinder engine that operates primarily at an air/fuel ratio that is lean of stoichiometry. The invention uses the cylinder deactivation system to control temperature and air/fuel ratio of an exhaust gas feedstream going into an aftertreatment device. The invention also increases the amount of fuel delivered to each non-deactivated cylinder by an amount sufficient to maintain operating power of the engine. The regeneration action includes desorbing NOx from a NOx adsorber catalyst, desulfating the NOx adsorber catalyst, and purging a diesel particulate trap.

Claims

1. A system to regenerate an exhaust aftertreatment device of a multicylinder engine that operates primarily at an air/fuel ratio that is lean of stoichiometry, comprising:

a controller operable to deactivate at least one cylinder using a cylinder deactivation system and operable to enrich a fuel charge to each non-deactivated cylinder using a fuel control system, based upon input from at least one sensor operable to monitor an engine operating condition and based upon input from a sensor operable to measure exhaust gas;

wherein the exhaust aftertreatment system comprises a diesel particulate trap, an oxidation catalyst, and an NOx adsorber;

wherein said controller is operable to maintain an operating point of the engine, and

wherein said controller operates the engine at an air/fuel ratio that is rich of stoichiometry such that a temperature of the NOx adsorber is sufficient to desulfate the NOx adsorber.

2. The system of claim 1, wherein the diesel particulate trap is catalyzed.

3. The system of claim 1, wherein the multicylinder engine comprises a compression-ignition engine.

4. The system of claim 1, wherein the multicylinder engine comprises a direct-injections spark-ignition engine.

5. The system of claim 1, wherein the multicylinder engine comprises a homogeneous charge, compressor ignition engine.

6. The system of claim 1, wherein the sensor operable to measure exhaust gas comprises an exhaust gas oxygen sensor.

7. The system of claim 1, wherein the sensor operable to measure exhaust gas comprises a wide-range air/fuel sensor.

8. The system of claim 1, wherein the sensor operable to measure exhaust gas comprises a gas constituent sensor.