Heat pipe heat spreader with internal solid heat conductor

Abstract

The invention is a flat heat pipe heat spreader with the addition of a solid heat conductive structure spanning the internal space in the heat pipe only at the region of contact with the heat source. Capillary wick is also bonded to the sides of the solid heat conductive structure. Thus, the solid structure provides both direct heat conduction from the heat source to a heat sink mounted atop the heat spreader and also acts as an extended evaporator surface within the heat pipe. The combination furnishes a decrease in the thermal resistance compared to a heat pipe without the solid structure.

What is claimed as new and for which Letters Patent of the United States are desired to be secured is:  
     
         1 . A heat pipe heat spreader comprising: 
 a first plate and a second plate shaped and sealed together to form an enclosure, with non-condensible gases evacuated from within the enclosure and sufficient liquid loaded into the enclosure to form an operable heat pipe;    a solid heat conductive structure spanning the space within the enclosure between the first and second plates and attached to the two plates with a heat conductive bond, the heat conductive structure being located at that part of the inner surface of one plate where the outer surface of the plate is in contact with a heat source being cooled by the heat pipe; and    capillary wick attached to the inside surface of the plate which is in contact with the heat source cooled.    
     
     
         2 . The heat pipe heat spreader of  claim 1  wherein the capillary wick is attached to the interior surfaces of both plates.  
     
     
         3 . The heat pipe heat spreader of  claim 1  wherein the capillary wick is attached to the interior surfaces of both plates and to the surfaces of the solid heat conductive structure which span the space between the two plates, and the capillary wick on the solid heat conductive structure is continuous with the capillary wick on the interior surfaces of the two plates.  
     
     
         4 . The heat pipe heat spreader of  claim 1  wherein the cross section of the solid heat conductive structure is the same as the size of the contact surface of a device being cooled by the heat pipe.