Systems and methods for purging reductant from a reductant injector

• Main Authors: Colin L Norris, Taren Dehart, Neha Verma, Nicholas Blodgett
• Format: Patent
• Language: English
• Published: 21.04.2021
• 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 reductant insertion system for inserting reductant into an aftertreatment system via a reductant injector comprises a reductant insertion assembly comprising a pump operatively coupled to the reductant injector via a reductant delivery line. A compressed gas source is operatively coupled to the reductant injector and provides a compressed gas to the reductant injector for gas assisted delivery of the reductant. A controller is operatively coupled to the compressed gas source and the reductant insertion assembly and configured to determine whether there is a reductant demand for the reductant. In response to there being no reductant demand, the controller stops the pump and activates the compressed gas source for a predetermined time so as to provide compressed gas to the reductant injector at a pressure sufficient to force reductant contained in the reductant injector upstream towards the reductant insertion assembly via the reductant delivery line while the pump is stopped.