| US 7,500,357 B2 | ||
| System for assisting regeneration of a storage/release NOx trap for a motor vehicle diesel engine | ||
| Ali Chaouche, Paris (France); Djamal Medioun, Colombes (France); Yvon Beauge, Rungis (France); Piet Ameloot, Neuilly sur Seine (France); and Mickael Gascoin, Colombes (France) | ||
| Assigned to Peugeot Citron Automobiles SA, Velizy-Villacoublay (France) | ||
| Appl. No. 10/532,229 PCT Filed Oct. 14, 2003, PCT No. PCT/FR03/03025 § 371(c)(1), (2), (4) Date Oct. 24, 2005, PCT Pub. No. WO2004/038205, PCT Pub. Date May 06, 2004. |
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| Claims priority of application No. 02 13256 (FR), filed on Oct. 23, 2002. | ||
| Prior Publication US 2006/0107652 A1, May 25, 2006 | ||
| Int. Cl. F01N 3/00 (2006.01) | ||
| U.S. Cl. 60—295 [60/274; 60/278; 60/285; 60/301] | 20 Claims |
| 18. A method of assisting regeneration of a storage/release NOx trap integrated in an exhaust line of a motor vehicle diesel
engine, comprising:
admitting gas into the engine,
injecting fuel into the cylinders thereof in the form of at least pilot and main injections, and
controlling at least one of (i) said gas admission and (ii) said fuel injection for periodically switching the engine between
a lean mixture standard operating mode in which NOx is stored in the trap and a rich mixture regeneration operating mode in
which NOx is released from the trap and the trap is regenerated, for engine loads below a predetermined threshold value,
wherein said method further comprises, in the rich-mixture regeneration operating mode,
triggering at least two pilot injections in a crankshaft angle range from approximately 50° to approximately 5° ahead of the
top dead centre point of the cylinder concerned, and
triggering the main injection in an undercalibrated range up to a crankshaft angle of approximately 35° after the top dead
centre point.
|