Patent ID: 8122709
Filing Date: 2012-02-28
Classification: B01D,F01N,Y02T,Y10T

Abstract:
1. A device for delivering a reducing agent to an exhaust system of an internal combustion engine, comprising: a feed pump for pumping the reducing agent from a tank into the exhaust system, the feed pump having a compression side and a suction side; a metering device disposed between the feed pump and the exhaust system, the metering device intermittently delivering the reducing agent which is pumped continuously by the feed pump into the exhaust system, and the metering device selectively connecting the compression side of the feed pump to, or disconnecting it from, the suction side of the feed pump; a control unit for triggering the metering device; and an injection nozzle for injecting the reducing agent into the exhaust system, the injection nozzle being disposed between the metering device and the exhaust system and being controlled by a pressure of the reducing agent delivered to the injection nozzle, wherein the control unit is arranged for triggering the metering device such that in the event that a delivery of reducing agent into the exhaust system is required, the compression side of the feed pump is disconnected from the suction side of the feed pump, so that the pressure of the reducing agent delivered to the injection nozzle opens the injection nozzle, wherein a pressure line leading from the compression side of the feed pump to the injection nozzle and an intake line leading from the tank to the suction side of the feed pump extend through the metering device, and wherein the metering device selectively connects the pressure line and the intake line to one another or disconnects them from one another.