Device for introducing a liquid substance into the exhaust gas of an internal combustion engine

Abstract

A device for introducing a liquid reducing agent into the exhaust gas of an internal combustion engine includes an injection device and a retaining device. By means of the latter, the injection device is retained at least indirectly in the vicinity of an exhaust gas conduit and a cooling device cools the retaining device. An intermediate portion is disposed between the retaining device and the injection device, and this portion at least regionally influences the heat flow between the injection device and the retaining device.

1 - 10 . (canceled) 
   
   
       11 . A device for introducing a liquid reducing agent into the exhaust gas of an internal combustion engine, the device comprising an injection device, a retaining device by which the injection device is retained at least indirectly in the vicinity of an exhaust gas conduit, and a cooling device which cools the retaining device, the cooling device including an intermediate heat transfer portion disposed between the retaining device and the injection device and at least regionally influencing the heat flow between the injection device and the retaining device. 
   
   
       12 . A device for introducing a liquid reducing agent into the exhaust gas of an internal combustion engine, the device comprising an injection device, a retaining device by which the injection device is retained at least indirectly in the vicinity of an exhaust gas conduit, a cooling device which cools the retaining device and the injection device, and an intermediate heat transfer element disposed between the retaining device and the injection device and at least regionally influencing the heat flow between the injection device and the retaining device. 
   
   
       13 . The device as defined by  claim 12 , wherein the intermediate portion includes a contact element disposed, in each case without play, between the injection device and a radially outer region of the retaining device, is in thermal communication with the injection device and the retaining device, in each case by two-dimensional contact, and is produced from a material with high thermal conductivity, and which at least in the contact regions with the injection device and/or the retaining device has a lesser rigidity than the injection device and/or the retaining device. 
   
   
       14 . The device as defined by  claim 13 , wherein the material of the contact element includes graphite. 
   
   
       15 . The device as defined by  claim 13 , wherein the contact element is annular, with a slight conicity in at least some regions. 
   
   
       16 . The device as defined by  claim 14 , wherein the contact element is annular, with a slight conicity in at least some regions. 
   
   
       17 . The device as defined by  claim 13 , wherein a contact region of the retaining element oriented toward the contact element has a slight conicity. 
   
   
       18 . The device as defined by  claim 14 , wherein a contact region of the retaining element oriented toward the contact element has a slight conicity. 
   
   
       19 . The device as defined by  claim 11 , wherein the cooling device comprises a cooling conduit disposed in the retaining device and through which a coolant flows. 
   
   
       20 . The device as defined by  claim 12 , wherein the cooling device comprises a cooling conduit disposed in the retaining device and through which a coolant flows. 
   
   
       21 . The device as defined by  claim 13 , wherein the cooling device comprises a cooling conduit disposed in the retaining device and through which a coolant flows. 
   
   
       22 . The device as defined by  claim 14 , wherein the cooling device comprises a cooling conduit disposed in the retaining device and through which a coolant flows. 
   
   
       23 . The device as defined by  claim 11 , further comprising thermal insulation means disposed between the retaining device and the contact element, on the one hand, and the exhaust gas conduit, on the other. 
   
   
       24 . The device as defined by  claim 12 , further comprising thermal insulation means disposed between the retaining device and the contact element, on the one hand, and the exhaust gas conduit, on the other. 
   
   
       25 . The device as defined by  claim 13 , further comprising thermal insulation means disposed between the retaining device and the contact element, on the one hand, and the exhaust gas conduit, on the other. 
   
   
       26 . The device as defined by  claim 11 , wherein the intermediate portion includes an air gap. 
   
   
       27 . The device as defined by  claim 12 , wherein the intermediate portion includes an air gap. 
   
   
       28 . The device as defined by  claim 19 , wherein the intermediate portion includes an air gap. 
   
   
       29 . The device as defined by  claim 27 , wherein the air gap between the injection device and the retaining device is present in a region adjacent to the exhaust gas conduit. 
   
   
       30 . A method for producing a device for introducing a liquid substance into the exhaust gas of an internal combustion engine, the device including a contact element that is a good thermal conductor disposed between a retaining device and an injection device, the method comprising deforming the contact element upon mounting of the injector on the retaining device, the contact element being deformed more markedly by the retaining device than by the injector and in such a way that it comes into contact two-dimensionally and without play with the injection device and the retaining device.