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U.S. Department of Energy
Office of Scientific and Technical Information

Exhaust recirculation

Patent ·
OSTI ID:7126697

An exhaust gas recirculation system for the reduction of nitrogen oxides in automobile exhaust is described that provides for the reduction of recirculation during engine idling without the prior-art complexities of moving parts. The system also achieves preheating and improved mixing and carburetion of the fuel-air mixture in the inlet header. Exhaust gases are recycled by means of a swirl chamber which receives the gases at a restricted opening in its upstream end. The chamber is in heat exchange relationship with the conventional intake manifold hot spot to facilitate heating of the latter. The swirl chamber discharges the hot exhaust gases at a restricted opening in its downstream end in opposition to the inlet flow of the fuel-air mixture at a location directly below the throttle valve. A second restricted duct opens into the induction conduit upstream of the throttle valve to receive inlet gases during idle and discharges tangentially into the swirl chamber to effect a swirling gas motion therein to inhibit exhaust flow during engine idle operation. The downstream end of the chamber consists of a thin plate adapted to flex with changing operating temperatures for the dislodging of exhaust gas contaminants adjacent its opening.

Assignee:
Chrysler Corp.
Patent Number(s):
US 3817230
OSTI ID:
7126697
Country of Publication:
United States
Language:
English