Thermosyphon and method for producing it

Abstract

The present invention relates to thermosyphons, in particular for use in the cooling of electronic components. In a first embodiment a thermosyphon is manufactured by extruding a base ( 1 ) and milling a channel structure in the base to produce a plurality of fins ( 5 ) extending vertically from the base. A lid ( 3 ) comprising a number of fins ( 4 ) extending vertically from the lid is placed over the heat sink channel structure so that a thermosyphon of an expanding channel system is formed. In a second embodiment the evaporator and condenser sections are separated and connected by pipes. To form a leak proof seal between the lid and the base, joining is preferably done by friction stir welding. By providing an extruded thermosyphon, heat transfer is made more efficient than when junctions are used. The present invention provides a new way of efficiently manufacturing an integrated structure, while keeping the heat transfer of the structure high.

1 . A thermosyphon comprising a base, a condenser section and an evaporator section conducting heat from a heat source by the use of a working fluid, wherein the evaporator and/or the condenser section has an internal structure providing an extended surface area, where at least a part of the internal structure has been produced by extrusion.  
     
     
         2 . The thermosyphon according to  claim 1 , wherein the condenser and the evaporator sections are integrated into a confined chamber, the chamber being sealed by a lid.  
     
     
         3 . The thermosyphon according to  claim 2 , wherein the extruded part of the thermosyphon is an integrated part of the lid.  
     
     
         4 . A The thermosyphon according to  claim 1 , wherein the condenser and the evaporator sections are separate structures joined by pipes transporting the working fluid.  
     
     
         5 . The thermosyphon according to  claim 4 , where the lid is extruded and comprises at least a part of the internal structure.  
     
     
         6 . The thermosyphon according to  claim 2 , wherein the lid is attached by friction stir welding.  
     
     
         7 . The thermosyphon according to  claim 1 , wherein at least a part of the thermosyphon is made of aluminum or an aluminum alloy.  
     
     
         8 . The thermosyphon according to  claim 1 , wherein the structure comprises heat dissipating fins extending from the base towards the outside of the thermosyphon.  
     
     
         9 . A method of producing a thermosyphon structure according to  claim 1 , wherein at least a part of the internal structure is produced by extrusion.  
     
     
         10 . The method of producing a thermosyphon according to  claim 9 , wherein the lid is attached to the base by friction stir welding.  
     
     
         11 . Use of a thermosyphon according to  claim 1  for the cooling of electronic components.