Exhaust recirculation ratiometer esp. for vehicular combustion engine - opens pneumatic recirculation valve under electronic control, responsive to intake temps., engine speed and load

摘要

Combustion prods. from the exhaust manifold (14) pass through a pneumatically actuated valve (18) and a recirculation pipe (16) to the inlet manifold (12). Air for operation of the valve (18) is drawn by an electric control valve (24) from the intake at a branching point downstream from the throttle flap (22). Two temp. sensors, one (30) at the mouth of the recirculation pipe (16) and the other (32) just below the branching point, are wired to an electronic controller (28). ADVANTAGE - Ratio of recirculated exhaust gas to combustion air supply is measured reliably and controlled with precision by simple appts.