Closed loop programmable EGR with coolant temperature sensitivity

Patent · Tue Aug 14 00:00:00 EDT 1979

OSTI ID:6062362

Toelle, A D

A closed loop programmable EGR control system is disclosed. The EGR control system comprises a first read only memory having a look up table of base EGR pulse widths as a function of engine speed and absolute manifold pressure. This base EGR pulse width is corrected to a total desired pulse width by adding a correction pulse width obtained from a second read only memory. The second ROM stores values of the correction pulse width in a look up table as a function of engine speed and engine coolant temperature. This desired value of EGR pulse width is then compared to the actual EGR flow as sensed directly by a differential pressure transducer located in the exhaust gas recirculation conduit and an error signal is generated therefrom. The error signal is subsequently used to operate a solenoid pilot valve that alternately applies either a vacuum or atmospheric vent at a controllable rate to an EGR valve regulating the amount of exhaust gas recirculated to thereby reduce the error between the actual and desired EGR values.

• Assignee: Bendix Corp.
• Patent Number(s): US 4164206
• OSTI ID: 6062362
• Resource Relation: Patent File Date: Filed date 19 Jan 1978
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
AUTOMOBILES
EXHAUST RECIRCULATION SYSTEMS
DESIGN
AIR POLLUTION CONTROL
CLOSED-CYCLE SYSTEMS
INTERNAL COMBUSTION ENGINES
NITROGEN OXIDES
CHALCOGENIDES
ENGINES
EQUIPMENT
EXHAUST SYSTEMS
NITROGEN COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
POLLUTION CONTROL
POLLUTION CONTROL EQUIPMENT
VEHICLES
330700* - Advanced Propulsion Systems- Emission Control