Secondary air control valve

Abstract

A secondary air control valve connected to an exhaust system includes a passage forming member and a valve mechanism. The passage forming member includes a container unit and a plurality of fins. The container unit that defines therein an exit cavity and an exit passage. The plurality of fins projects from the container unit into the exit cavity such that the plurality of fins collides with counter-flow exhaust gas that counter-flows in a direction from the exit passage to the exit cavity through the first opening. The plurality of fins divides the exit cavity into a plurality of cavities, in which counter-flow exhaust gas forms a plurality of vortex flows.

1 . A secondary air control valve connected to an exhaust system, which allows exhaust gas to flow therethrough, wherein the secondary air control valve supplies secondary air to the exhaust system, the secondary air control valve comprising:
 a passage forming member that defines a passage, through which secondary air is supplied to the exhaust system; and   a valve mechanism provided in the passage, wherein:   the passage forming member includes:
 a container unit that defines therein:
 an exit cavity provided between the valve mechanism and the exhaust system; and 
 an exit passage having a first opening communicated with the exit cavity and having a second opening communicated with the exhaust system; and 
 
 a plurality of fins that projects from the container unit into the exit cavity such that the plurality of fins collides with counter-flow exhaust gas that counter-flows in a direction from the exit passage to the exit cavity through the first opening, the plurality of fins dividing the exit cavity into a plurality of cavities, in which counter-flow exhaust gas forms a plurality of vortex flows. 
   
     
     
         2 . The secondary air control valve according to  claim 1 , wherein:
 the plurality of fins includes an obstacle fin that is provided on an imaginary extension of the exit passage such that the obstacle fin directly collides with counter-flow exhaust gas; and   the obstacle fin divides counter-flow exhaust gas into at least a first flow and a second flow.   
     
     
         3 . The secondary air control valve according to  claim 2 , wherein:
 the plurality of fins further includes a center sectioning fin that defines a first cavity, into which the first flow is mainly introduced, and a second cavity, into which the second flow is mainly introduced, within the exit cavity.   
     
     
         4 . The secondary air control valve according to  claim 3 , wherein:
 the plurality of fins includes:
 a first vortex flow guide fin that is provided as an island within the first cavity, the first vortex flow guide fin defining therearound an annular cavity that causes counter-flow exhaust gas to form a vortex flow; and 
 a second vortex flow guide fin that is provided as an island within the second cavity, the second vortex flow guide fin defining therearound an annular cavity that causes counter-flow exhaust gas to form a vortex flow. 
   
     
     
         5 . The secondary air control valve according to  claim 4 , wherein:
 the plurality of fins includes:
 a first terminal sectioning fin that defines a plurality of terminal cavities within the first cavity, the first terminal sectioning fin dividing the first flow into a plurality of flows directed respectively to the plurality of terminal cavities; and 
 a second terminal sectioning fin that defines a plurality of terminal cavities within the second cavity, the second terminal sectioning fin dividing the second flow into a plurality of flows directed respectively to the plurality of terminal cavities. 
   
     
     
         6 . The secondary air control valve according to  claim 1 , wherein:
 the plurality of fins includes a vortex flow guide fin that is provided as an island within the exit cavity; and   the vortex flow guide fin defines therearound an annular cavity that causes counter-flow exhaust gas to form a vortex flow.   
     
     
         7 . The secondary air control valve according to  claim 1 , wherein:
 the plurality of fins includes a plurality of terminal sectioning fins that defines a plurality of terminal cavities within the exit cavity; and   the plurality of terminal sectioning fins divides counter-flow exhaust gas into a plurality of flows that flows directed respectively to the plurality of terminal cavities.   
     
     
         8 . The secondary air control valve according to  claim 1 , wherein:
 the container unit includes:
 a tubular side wall having an opening at one end adjacent the valve mechanism; and 
 a bottom wall provided at the other end of the side wall; 
   the container unit defines therein the exit passage and the first opening such that counter-flow exhaust gas flows into the exit cavity along an inner surface of the bottom wall; and   the plurality of fins includes:
 a connected fin connected to both the side wall and the bottom wall and projecting from the side wall; and 
 a separated fin connected only to the bottom wall and separate from the side wall. 
   
     
     
         9 . The secondary air control valve according to  claim 8 , wherein:
 each of the plurality of fins has a plate shape that projects from the bottom wall in a direction of a height of the side wall;   each of the plurality of fins has a height smaller than the height of the side wall; and   the exit cavity includes a cavity segment defined between the plurality of fins and the valve mechanism and extending along the opening of the side wall.   
     
     
         10 . The secondary air control valve according to  claim 1 , wherein:
 the valve mechanism defines a valve passage that allows the secondary air to flow therethrough into the exit cavity;   the plurality of fins includes a fin located at a position on an imaginary extension of the valve passage; and   the fin forms along the imaginary extension of the valve passage.   
     
     
         11 . The secondary air control valve according to  claim 1 , wherein the container unit has a plurality of outer fins formed on an outer surface thereof.