Electrically controlled exhaust valve

Abstract

An exhaust system for a motor vehicle having a variable displacement engine includes an exhaust valve assembly that is moveable between an open position and a position blocking at least some of the exhaust gases. The blocking of some the exhaust gases increases backpressure that reflects sound waves. The reflection of sound waves provides for the conditioning of noises eminating from the exhaust system. The exhaust valve assembly utilizes an electric actuator. The exhaust valve assembly includes heat insulation features for isolating the electric actuator from heat radiating from the exhaust pipe.

1 . An exhaust valve assembly comprising: 
 a valve plate movable within an exhaust pipe between an open and a closed position; and    an electric actuator for moving said valve plate.    
   
   
       2 . The assembly as recited in  claim 1 , comprising a valve neck for supporting said electric actuator a distance from said exhaust pipe.  
   
   
       3 . The assembly as recited in  claim 2 , comprising a support housing mounted to said valve neck for supporting said electric actuator.  
   
   
       4 . The assembly as recited in  claim 3 , wherein said support housing includes a plate disposed between said electric actuator and said exhaust pipe for shielding said actuator from heal  
   
   
       5 . The assembly as recited in  claim 3 , wherein said valve neck comprises a tubular cross section having a first mount adjacent a first end for attachment to an exhaust pipe and a second mount adjacent a second end opposite said first end for supporting said support housing.  
   
   
       6 . The assembly as recited in  claim 3 , wherein said valve neck comprises a cross-section smaller in a direction transverse to said exhaust pipe than a cross section of said support housing transverse to said exhaust pipe.  
   
   
       7 . The assembly as recited in  claim 1 , wherein said electric actuator compromises a linearly movable element.  
   
   
       8 . The assembly as recited in  claim 1 , wherein said electric actuator comprises a rotatably movable element.  
   
   
       9 . The assembly as recited in  claim 1 , comprising an actuation tube having a tubular cross section rotatable by said electric actuator for moving said valve plate.  
   
   
       10 - 13 . (canceled)  
   
   
       14 . An exhaust system for a motor vehicle comprising: 
 an exhaust pipe directing exhaust gases; and    an exhaust valve assembly for increasing a back pressure within said exhaust pipe for reflecting sound waves, said exhaust valve assembly comprising a valve plate movable about an axis of rotation for blocking a portion of exhaust gases flowing through said exhaust pipe, and an electric actuator for moving said valve plate.    
   
   
       15 . The system as recited in  claim 14 , comprising a valve neck disposed about said axis of rotation for supporting and spacing said electric actuator a distance from said exhaust pipe.  
   
   
       16 . The system as recited in  claim 15 , comprising a support housing supported by said valve neck, wherein said valve neck comprises a cross-section transverse to said exhaust pipe smaller than a cross-section of said support housing in a direction transverse to said exhaust pipe.  
   
   
       17 . The system as recited in  claim 16 , wherein said support housing comprises a plate disposed between said electric actuator and said exhaust pipe for shielding said electric actuator from heat emitted from said exhaust pipe.  
   
   
       18 . The system as recited in  claim 14 , comprising an actuation tube having a tubular cross section rotatable by said electric actuator for moving said valve plate.  
   
   
       19 . The system as recited in  claim 14 , wherein said valve plate creates a tuning effect replicating an exhaust pipe of a diameter smaller than said exhaust pipe.  
   
   
       20 . The system as recited in  claim 14 , comprising an actuation tube having a solid shaft rotatable by said electric actuator for moving said valve plate.  
   
   
       21 . The system as recited in  claim 14 , comprising an actuation tube having a hollow shaft rotatable by said electric actuator for moving said valve plate.  
   
   
       22 . The system as recited in  claim 14 , comprising an actuation tube having a solid portion and a hollow portion rotatable by said electric actuator For moving said valve plate.  
   
   
       23 . The system as recited in  claim 1  wherein said electric actuator includes a first pull coil for initiating movement of said valve plate and a second hold coil for holding said valve plate in a desired position.  
   
   
       24 . The system as recited in  claim 14  wherein said electric actuator includes a first pull coil for initiating movement of said valve plate and a second hold coil for holding said valve plate in a desired position.  
   
   
       25 . The system as recited in  claim 5  wherein said valve plate is rotatable about an axis and said valve neck is mounted about said axis.  
   
   
       26 . The system as recited in  claim 15 , wherein said valve neck includes a hollow tube having a first mount adjacent a first end for attachment to said exhaust pipe and a second mount adjacent a second end opposite said first end for supporting said electric actuator.