Assembly and Method for Introducing a Reducing Agent into the Exhaust Pipe of an Exhaust System of an Internal Combustion Engine

Abstract

An assembly and method for introducing a reducing agent into an exhaust pipe of an exhaust system of an internal combustion engine, in particular of a motor vehicle includes a feed connector which opens into the exhaust pipe and has a wall; a feed device for reducing agents which opens into the feed connector; and a device that generates a gas flow which is additional to the reducing agent flow and lines the wall of the feed connector.

1 . An assembly that introduces a reducing agent into an exhaust pipe of an exhaust system of an internal combustion engine, in particular of a motor vehicle, comprising:
 a feed connector which opens into the exhaust pipe and includes a wall;   a feed device which opens into the feed connector and introduces a reducing agent flow; and   a device that generates an additional gas flow which is additional to the reducing agent flow and lines the wall of the feed connector.   
   
   
       2 . The assembly according to  claim 1 , wherein the additional gas flow is compressed fresh air. 
   
   
       3 . The assembly according to  claim 1 , wherein the additional gas flow is exhaust gas. 
   
   
       4 . The assembly according to  claim 1 , wherein the device includes an inlet opening for the additional gas flow. 
   
   
       5 . The assembly according to  claim 4 , wherein the inlet opening is arranged in the wall of the feed connector. 
   
   
       6 . The assembly according to  claim 4 , wherein the inlet opening is formed in a region of an orifice of the feed connector into the exhaust pipe. 
   
   
       7 . The assembly according to  claim 1 , wherein the device is configured such that the additional gas flow is formed as a swirl flowing in the feed connector. 
   
   
       8 . The assembly according to  claim 1 , wherein the device includes a guide member arranged in the feed connector. 
   
   
       9 . The assembly according to  claim 8 , wherein the guide member extends from the feed device at least partially along the wall of the feed connector. 
   
   
       10 . The assembly according to  claim 8 , wherein the guide member lines the wall of the feed connector, a gap being formed at least in sections between the wall and the guide member. 
   
   
       11 . The assembly according to  claim 8 , wherein the guide member projects at least partially into the exhaust pipe. 
   
   
       12 . The assembly according to claim, wherein the device includes an inlet opening that is formed in a region of an orifice of the feed connector into the exhaust pipe, and wherein a section of the guide member extends into the exhaust pipe on a side of the orifice that is upstream with respect to the exhaust gas flow. 
   
   
       13 . The assembly according to  claim 8 , wherein the guide member includes a continuously surrounding peripheral wall. 
   
   
       14 . The assembly according to  claim 13 , wherein the guide member includes one or more openings in the continuously surrounding peripheral wall. 
   
   
       15 . The assembly according to  claim 8 , wherein the guide member is arranged to deflect the additional gas flow to form a swirl flowing in the feed connector. 
   
   
       16 . The assembly according to  claim 1 , wherein the feed connector is arranged at an angle of from 20° to 70° in relation to the exhaust pipe. 
   
   
       17 . The assembly according to  claim 1 , wherein downstream of the feed connector, a static mixing element is arranged in the exhaust pipe. 
   
   
       18 . The assembly according to  claim 1 , wherein the exhaust pipe has a bend of approximately 20° to 70° in a region of the feed connector. 
   
   
       19 . The assembly according to  claim 1 , wherein the reducing agent flow includes a reducing agent that is an aqueous urea solution. 
   
   
       20 . The assembly according to  claim 1 , wherein the feed device a low-pressure fuel injection valve. 
   
   
       21 . The assembly according to  claim 1 , wherein the additional gas flow is at least largely free of reducing agent and lines the wall of the feed connector opening into the exhaust pipe, and wherein the reducing agent is injected by the feed device which is arranged on the feed connector. 
   
   
       22 . The assembly according to  claim 21 , wherein additional gas flow forms a swirl provided in the feed connector. 
   
   
       23 . A method of introducing a reducing agent into an exhaust pipe of an exhaust system of an internal combustion engine, in particular of a motor vehicle, including the following steps:
 (a) generating a gas flow which is additional to a the reducing agent flow and is at least largely free of reducing agent and lines a wall of a feed connector opening into the exhaust pipe; and   (b) injecting the reducing agent with a feed device arranged on the feed connector.   
   
   
       24 . (canceled)