REDUCTANT DELIVERY UNIT FOR AUTOMOTIVE SELECTIVE CATALYTIC REDUCTION WITH THERMALLY OPTIMIZED PEAK-AND-HOLD ACTUATION BASED ON AN INJECTOR OPEN EVENT

• Main Authors: COSBY DOUGLAS EDWARD, VAN VUUREN WILLEM NICOLAAS
• Format: Patent
• Language: English
• Published: 25.12.2014
• Subjects: BLASTING; ENGINE PLANTS IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNALCOMBUSTION ENGINES; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES ORENGINES IN GENERAL; HEATING; LIGHTING; MACHINES OR ENGINES IN GENERAL; MECHANICAL ENGINEERING; STEAM ENGINES; WEAPONS

A trigger circuit is provided for a peak and hold driver circuit for a reductant delivery unit (RDU) having a solenoid-operated injector for selective catalytic reduction (SCR) after-treatment for vehicles. The peak and hold driver circuit is constructed and arranged to actuate the injector in a rise-to-peak current phase followed by a low current hold phase. The trigger circuit includes an injector open detection circuit constructed and arranged, based on a detected opening event of the injector, to trigger a transition from the rise-to-peak phase to the subsequent hold phase of the injector.