Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Exhaust recirculation

Patent ·
OSTI ID:7232446

An exhaust gas recirculation system for the reduction of nitrogen oxide emissions from internal combustion engine exhaust is described that is uncomplicated by moving parts, thus avoiding problems associated with prior-art recirculation systems. The system also results in preheating and improved mixing of the fuel-air mixture in the inlet header. A recycling duct receives the exhaust gases at a restricted upstream end of the exhaust system and passes in heat exchange relationship through a conventional intake manifold hot spot to facilitate heating of the latter. The hot exhaust gases are discharged at a restricted downstream end of the exhaust system in opposition to the inlet flow of the fuel-air mixture directly below the throttle valve. A second restricted duct that extends within the sidewall of the carburetor inlet induction conduit and bypasses the throttle valve opens into the induction conduit upstream of the throttle valve to receive inlet gases during idle. The second duct discharges into the recycling duct between the latter's upstream and downstream restrictions to inhibit exhaust flow through the recycling duct during engine idle operation.

Assignee:
Chrysler Corp.
Patent Number(s):
US 3827412
OSTI ID:
7232446
Country of Publication:
United States
Language:
English