Internal combustion engine comprising a gas conveying system and operating method therefor

Abstract

1. Internal combustion engine comprising a gas conveying system and operating method therefor. 2.1 The invention proposes an internal combustion engine ( 1 ) having a gas conveying system with a turbine ( 7 ) which can be driven by an airstream and a pump ( 8 ) which can be driven by the turbine ( 7 ) and by means of which gas can be fed to the exhaust system ( 3, 4, 5 ), as well as an operating method therefor. 2.2. According to the invention, when the internal combustion engine ( 1 ) is starting up, the quantity of fuel injected into it is set as a function of the delivery capacity of the pump ( 8 ). 2.3. Use in motor vehicles, in particular in passenger cars having an internal combustion engine with fuel injection.

1 . An internal combustion engine with fuel injection, having an intake line ( 2 ), in which a throttle element ( 6 ) is arranged, an exhaust system ( 3 ,  4 ,  5 ) and a gas conveying system having 
 a turbine ( 7 ), which can be driven by an air stream and to which a turbine inlet line ( 9 ) and a turbine outlet line ( 10 ) are connected, and    a pump ( 8 ), which can be driven by the turbine ( 7 ) and has a pump inlet line ( 11 ) and a pump outlet line ( 12 ), via which gas delivered by the pump ( 8 ) can be fed to the exhaust system ( 3 ,  4 ,  5 ),    characterized in that when the internal combustion engine ( 1 ) is starting up, the quantity of fuel injected into it can be set as a function of the delivery capacity of the pump ( 8 ).    
   
   
       2 . The internal combustion engine as claimed in  claim 1 , characterized in that the turbine ( 7 ) can be driven by a part-stream of the combustion air taken in by the internal combustion engine ( 1 ) via the intake line ( 2 ), the part-stream being produced by a pressure gradient which is present across the throttle element ( 6 ).  
   
   
       3 . The internal combustion engine as claimed in  claim 1 , characterized in that when the engine is starting up, the speed of the internal combustion engine ( 1 ) can be set before the fuel injection commences, by actuation of the internal combustion engine ( 1 ) or by actuation of an auxiliary unit assigned to the internal combustion engine ( 1 ).  
   
   
       4 . The internal combustion engine as claimed in  claim 1 , characterized in that when the engine is starting up, the throttle element ( 6 ) can be set as a function of a pressure in the intake line ( 2 ).  
   
   
       5 . The internal combustion engine as claimed in  claim 1 , characterized in that the turbine ( 7 ) can be driven by an airstream which is generated by a gas conveying unit ( 15 ;  16 ) which is arranged in the turbine inlet line ( 9 ) or in the turbine outlet line ( 10 ) or is connected to the turbine inlet line ( 9 ) or to the turbine outlet line ( 10 ).  
   
   
       6 . The internal combustion engine as claimed in  claim 5 , characterized in that the gas conveying unit is designed as an electrically driven gas conveying unit ( 15 ).  
   
   
       7 . The internal combustion engine as claimed in  claim 5 , characterized in that the gas conveying unit is designed as an evacuable gas vessel ( 16 ) arranged in the turbine outlet line ( 10 ).  
   
   
       8 . The internal combustion engine as claimed in  claim 1 , characterized in that the gas stream delivered by the pump ( 8 ) can be set as a function of an air/fuel ratio in the exhaust system ( 3 ,  4 ,  5 ).  
   
   
       9 . The internal combustion engine as claimed in  claim 1 , characterized in that the gas stream delivered by the pump ( 8 ) can be fed to an exhaust manifold ( 3 ) assigned to the exhaust system ( 3 ,  4 ,  5 ) and/or direct to a catalytic converter ( 5 ) assigned to the exhaust system ( 3 ,  4 ,  5 ).  
   
   
       10 . The internal combustion engine as claimed in  claim 1 , characterized in that exhaust gas can be fed to the pump ( 8 ) via the pump inlet line ( 11 ), and the exhaust-gas stream delivered by the pump ( 8 ) can be fed to the intake line ( 2 ).  
   
   
       11 . The internal combustion engine as claimed in  claim 1 , characterized in that a reduced-pressure vessel ( 17 ) connected via the pump inlet line ( 11 ) can be evacuated by the pump ( 8 ).  
   
   
       12 . A method for operating an internal combustion engine with fuel injection and having 
 an intake line ( 2 ), in which a throttle element ( 6 ) is arranged,    an exhaust system ( 3 ,  4 ,  5 ) and    a gas conveying system, which comprises a turbine ( 7 ) that can be driven by an airstream and a pump ( 8 ) that can be driven by the turbine ( 7 ),    in which method, at least when the engine is starting up, gas delivered by the pump ( 8 ) is fed to the exhaust system ( 3 ,  4 ,  5 ), characterized in that when the internal combustion engine ( 1 ) is starting up, the quantity of fuel injected is set as a function of the delivery capacity of the pump ( 8 ).    
   
   
       13 . The method as claimed in  claim 12 , characterized in that when the engine is starting up, before the fuel injection begins the throttle element ( 6 ) is held predominantly closed and is only opened after the pump has reached a minimum delivery capacity.  
   
   
       14 . The method as claimed in  claim 12 , characterized in that the engine speed of the internal combustion engine ( 1 ) is increased as it is starting up before the fuel injection begins.  
   
   
       15 . The method as claimed in  claim 12 , characterized in that the turbine ( 7 ), at least from time to time, is driven by an airstream which is delivered by a gas conveying unit ( 15 ;  16 ) which is arranged in the turbine inlet line ( 9 ) or the turbine outlet line ( 10 ) or is connected to the turbine inlet line ( 9 ) or the turbine outlet line ( 10 ).  
   
   
       16 . The method as claimed in  claim 12 , characterized in that the airstream delivered by the pump ( 8 ) is set as a function of an air/fuel ratio in the exhaust system ( 3 ,  4 ,  5 ).  
   
   
       17 . The method as claimed in  claim 12 , characterized in that one of at least two addition points ( 13 ,  14 ) in the exhaust system ( 3 ,  4 ,  5 ) at which the airstream delivered by the pump ( 8 ) is added to the exhaust gas is selected as a function of the operating state of the internal combustion engine ( 1 ).  
   
   
       18 . The method as claimed in  claim 12 , characterized in that the airstream delivered by the pump ( 8 ) cools a definable part of the exhaust system ( 3 ,  4 ,  5 ) if a predeterminable threshold value for a temperature in the exhaust system ( 3 ,  4 ,  5 ) is exceeded.  
   
   
       19 . The method as claimed in  claim 12 , characterized in that the pump ( 8 ) at least from time to time removes exhaust gas from the exhaust system ( 3 ,  4 ,  5 ) and feeds it to the intake line ( 2 ).  
   
   
       20 . The method as claimed in  claim 12 , characterized in that a reduced-pressure vessel ( 17 ) assigned to the internal combustion engine ( 1 ) is evacuated by the pump ( 8 ) via the pump inlet line ( 11 ) in order to operate a servo system operated by reduced pressure.