Heat dissipation elements for reductant delivery unit for automotive selective catalytic reduction system

Abstract

An injector having at least one heat dissipation element used for providing a highly conductive path for transferring heat away from a valve portion of an injector. In one embodiment, the heat dissipation element is a cylindrical element, or conductive plug, in contact with the injector valve body and the injector housing. In one embodiment, the heat dissipation element is a plurality of cooling fins, each being in direct contact with the injector housing. The fins may be used in combination with the cylindrical element to serve as an additional heat evacuation conduction path, allowing the heat to be dissipated by convection through the large surface area provided by the fins. The cylindrical element may be made of copper, but it is also within the scope of the invention that any suitable thermally conductive material may be used.

What is claimed is: 
     
         1 . An apparatus, comprising:
 an injector, including:
 an actuator; 
 a valve portion; 
 an inlet tube for receiving diesel exhaust fluid; and 
 at least one heat dissipation element for transferring heat away from the valve portion; 
 wherein fluid flows through the inlet tube to the valve portion, and the actuator controls the movement of the valve portion to control the flow of fluid through the valve portion. 
   
     
     
         2 . The apparatus of  claim 1 , the at least one heat dissipation element further comprising a thermally conductive plug. 
     
     
         3 . The apparatus of  claim 2 , wherein the thermally conductive plug is made of a material selected from the group consisting of copper, steel, nickel, and aluminum. 
     
     
         4 . The apparatus of  claim 2 , the thermally conductive plug being made of a thermally insulating material. 
     
     
         5 . The apparatus of  claim 2 , further comprising;
 a lower valve body, the valve portion disposed in the lower valve body; and   a through-aperture, the through-aperture formed as part of the thermally conductive plug;   wherein, a portion of the lower valve body extends through the though-aperture of the thermally conductive plug.   
     
     
         6 . The apparatus of  claim 2 , further comprising:
 an outer lower shield, the thermally conductive plug located in a cavity formed as part of the outer lower shield;   an outer surface formed as part of the thermally conductive plug, the outer surface in contact with an outer wall of the outer lower shield; and   a lower surface formed as part of the thermally conductive plug, the lower surface adjacent the outer surface and in contact with a lower wall of the outer lower shield.   
     
     
         7 . The apparatus of  claim 1 , the at least one heat dissipation element further comprising at least one fin. 
     
     
         8 . The apparatus of  claim 7 , the at least one fin further comprising:
 a circular mounting flange portion connected to an outer surface of the injector; and   a circular projecting flange portion integrally formed with the circular mounting flange portion;   wherein heat is transferred away from the injector through the circular mounting flange portion and the circular projecting flange portion.   
     
     
         9 . The apparatus of  claim 8 , wherein the circular mounting flange portion is substantially perpendicular to the circular projecting flange portion. 
     
     
         10 . The apparatus of  claim 8 , the at least one fin further comprising a plurality of fins, each of the plurality of fins having a circular mounting flange portion and a circular projecting flange portion. 
     
     
         11 . The apparatus of  claim 1 , further comprising an outer circumferential wall formed by the circumferential mounting flange of each of the plurality of fins. 
     
     
         12 . An injector, comprising:
 an actuator;   a valve portion, the movement of the valve portion controlled by the actuator;   a lower valve body, the valve portion disposed in the valve body;   a thermally conductive plug substantially surrounding a portion of the valve body;   an outer lower shield, the thermally conductive plug located in a cavity formed as part of the outer lower shield; and   at least one fin attached to the outer lower shield;   wherein the thermally conductive plug and the at least one fin transfer heat away from the valve portion.   
     
     
         13 . The injector of  claim 12 , the thermally conductive plug further comprising a through-aperture, a portion of the lower valve body extending through the though-aperture. 
     
     
         14 . The injector of  claim 12 , the thermally conductive plug further comprising:
 an outer surface in contact with an outer wall of the outer lower shield; and   a lower surface adjacent the outer surface, the lower surface in contact with a lower wall of the outer lower shield.   
     
     
         15 . The injector of  claim 12 , the at least one fin further comprising:
 a circular mounting flange portion attached to the outer lower shield; and   a circular projecting flange portion integrally formed with the circular mounting flange portion;   wherein heat is transferred away from the outer lower shield through the circular mounting flange portion.   
     
     
         16 . The injector of  claim 15 , wherein the circular mounting flange portion is substantially perpendicular to the circular projecting flange portion. 
     
     
         17 . The injector of  claim 15 , the at least one fin further comprising a first fin, a second fin, and a third fin, wherein the first fin, the second fin, and the third fin are attached to and circumscribe the outer lower shield. 
     
     
         18 . The injector of  claim 17 , each of the first fin, the second fin, and the third fin further comprising a circular mounting flange portion and a circular projecting flange portion. 
     
     
         19 . The injector of  claim 18 , wherein the circular mounting flange portion of the first fin is adjacent the circular mounting flange portion of the second fin, and the circular mounting flange portion of the second fin is adjacent the circular mounting flange portion of the third fin. 
     
     
         20 . The injector of  claim 19 , further comprising an outer circumferential wall. 
     
     
         21 . The injector of  claim 20 , the outer circumferential wall further comprising the circular mounting flange portion of the first fin, the circular mounting flange portion of the second fin, and the circular mounting flange portion of the third fin. 
     
     
         22 . The injector of  claim 12 , wherein the thermally conductive plug is made of a material selected from the group consisting of copper, steel, nickel, and aluminum. 
     
     
         23 . The injector of  claim 12 , wherein the thermally conductive plug is made of a thermally insulating material.