Method and device for cleaning valves

Abstract

The invention relates to a method and a device for the catalytic combustion of fuel which is metered into the exhaust manifold of an internal combustion engine by an injection valve. Preferably, an oxidation catalyst is positioned in the exhaust manifold of the internal combustion engine. The metered fuel is atomized in an exhaust gas flow by the injection valve. An end of the invention valve facing the direction of the exhaust gas flow in an exhaust pipe is continuously or intermittently heated by a heating device. Alternatively, an end of the injection valve which is thermally decoupled from the injection valve is directly heated by the exhaust gas flow.

1 - 10 . (canceled) 
   
   
       11 . A method for catalytic combustion of fuel, which fuel an injection valve has metered into an exhaust line of an internal combustion engine, through the use of an oxidizing converter, comprising the steps of:
 a) the injection valve atomizing the metered-in fuel in an exhaust flow; and   b 1 ) a heating device continuously or periodically heating an end of the injection valve oriented toward the exhaust flow in an exhaust pipe; or   b 2 ) heating an end of the injection valve that is thermally decoupled from the injection valve directly by the exhaust flow.   
   
   
       12 . The method as reciting  claim 11 , wherein the metered-in fuel is atomized by means of an injection port disk accommodated at the end of the injection valve oriented toward the exhaust flow. 
   
   
       13 . The method as reciting  claim 11 , wherein in step b 1 ), the end of the injection valve oriented toward the exhaust flow is heated at regular intervals to a temperature level of approximately 600° C. or is heated to a temperature level of approximately 400° C. after additional fuel has been metered-in. 
   
   
       14 . The method as reciting  claim 11 , wherein in step b 2 ), the thermal decoupling of the end of the injection valve is achieved by means of a thermal insulation. 
   
   
       15 . A device for catalytic combustion of fuel, which fuel an injection valve has metered into an exhaust line of an internal combustion engine, comprising:
 an injection port disk equipped with a plurality of individual openings being situated at an end of the injection valve oriented toward exhaust flow in the exhaust line, the injection port disk being associated with a heating device, which heating device includes at least one heating wire, or the injection port disk being thermally decoupled from a valve body of the injection valve by means of a thermal insulation.   
   
   
       16 . The device as recited in  claim 15 , wherein the at least one heating wire extends along one of two surfaces of the injection port disk. 
   
   
       17 . The device as recited in  claim 16 , wherein the at least one heating wire is accommodated inside a cavity of the injection valve and is thermally insulated from the valve body of the injection valve. 
   
   
       18 . The device as recited in  claim 16 , wherein the at least one heating wire extends in a meandering fashion on one of the surfaces of the injection port disk. 
   
   
       19 . The device as recited in  claim 15 , wherein the thermal insulation is situated in a cavity above the injection port disk in the valve body. 
   
   
       20 . The device as recited in  claim 16 , wherein individual coils of the at least one heating wire extend with a spacing, which permits passage of fuel through individual openings of the injection port disk, or through openings of the thermal insulation are aligned with individual openings of the injection port disk. 
   
   
       21 . The device as recited in  claim 19 , wherein individual coils of the at least one heating wire extend with a spacing, which permits passage of fuel through individual openings of the injection port disk, or through openings of the thermal insulation are aligned with individual openings of the injection port disk.