Oxygen pumping device for control of the air fuel ratio

Patent · Tue Jun 27 04:00:00 EDT 1989

OSTI ID:5674586

Logothetis, E M; Hetrick, R E; Soltis, R E; Vassell, W C

This patent describes a method operating a two cell oxygen pumping device to control the air fuel ratio of an engine, the oxygen pumping device having a pumping cell and sensing cell. The method includes the steps of: introducing exhaust gas from the engine to a region between the pumping cell and the sensing cell; applying a pumping current to the pumping cell; sensing an EMF across the sensing cell; comparing an adjustable reference voltage with the sensed EMF; generating an error signal from the comparison between the reference voltage and the sensed EMF: changing the air fuel ratio in response to the error signal so as to reduce the absolute magnitude of the error signal, including the step of decreasing the engine air fuel ratio in response to a positive error signal until the measured EMF becomes equal to the reference voltage, and the step of increasing the engine air fuel ratio in response to a negative error signal until the measured EMF becomes equal to the reference voltage; establishing a predetermined desired air fuel ratio from a range of possible operating air fuel ratio values.

• Assignee: Ford Motor Co., Dearborn, MI
• Patent Number(s): US 4841934
• OSTI ID: 5674586
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
330100* -- Internal Combustion Engines
DESIGN
ELEMENTS
ENGINES
FUEL SYSTEMS
FUEL-AIR RATIO
HEAT ENGINES
INTERNAL COMBUSTION ENGINES
NONMETALS
OXYGEN
PUMPING
PUMPS