Heat exchanger and method of manufacture thereof

Abstract

Method of manufacturing a heat exchanger from a formable laminate ( 1, 11, 105 ) of a metal layer and a heat-seal layer whereby the laminate is sealed under heat and pressure to itself or to another similar laminate to form a flow channel for a heat exchange medium. Preferably the heat exchanger includes a series of fins ( 3, 106, 107 ) formed on the laminate ( 1, 11, 105 ) to increase heat transfer and may also include a water retaining layer ( 204 ).

1 . A heat exchange element comprising a formable laminate of a metal layer and a heat-seal layer, the laminate being provided on first and second surfaces with a plurality of generally corrugated fins, the fins being connected under heat and pressure in heat conducting relationship with the laminate to increase an effective surface area thereof, the laminate being sealed under heat and pressure to itself or to another similar laminate to form a flow channel for a heat exchange medium, the flow channel having fins on both an internal surface and an external surface, the heat exchange element further comprising a water-retaining layer surface, the heat exchange, element further comprising a water-retaining layer provided in the fins on at least one of the surfaces.  
     
     
         2 . The heat exchange element according to  claim 1 , wherein the metal layer comprises soft annealed aluminium.  
     
     
         3 . The heat exchange element according to  claim 1 , wherein the metal layer has a thickness of between 25 microns and 120 microns, preferably around 70 microns.  
     
     
         4 . The heat exchange element according to  claim 1 , wherein the heat-seal layer is substantially coextensive with the metal layer.  
     
     
         5 . The heat exchange element according to  claim 1 , wherein the heat-seal layer is provided on both surfaces of the metal layer.  
     
     
         6 . The heat exchange element according to  claim 1 , wherein the water-retaining layer is provided on only one surface of the fins.  
     
     
         7 . (canceled)  
     
     
         8 . (canceled)  
     
     
         9 . (canceled)  
     
     
         10 . The heat exchange element according to  claim 1 , wherein the fins comprise a formable, laminate of a metal layer and a heat-seal layer.  
     
     
         11 . The heat exchange element according to  claim 1 , wherein the flow channel comprises an elongate flat tube of generally rectangular cross-section.  
     
     
         12 . The heat exchange element according to  claim 11 , wherein the tube comprises a first laminate portion having lateral edges, the edges being folded together and sealed to form an elongate seam.  
     
     
         13 . The heat exchange element according to  claim 11 , wherein the tube comprises first and second laminate portions each having lateral edges, the first and second laminate portions being sealed to one another along their respective edges.  
     
     
         14 . A method of manufacturing a heat exchanger, comprising: 
 providing a plastically deformable first metal laminate;    providing a plastically deformable second laminate having first and second surfaces;    providing a plastically deformable third metal laminate;    plastically forming the first and third laminates into generally corrugated shaped having a series of troughs;    connecting the first and third laminates to the respective firs and second surfaces of the second laminate at the series of troughs to form a heat-transmitting wall with heat-conducting fins on both sides; and    sealing the second laminate to itself or to another similar laminate to form a flow channel wherein the first and third laminates or the second laminate comprise a heat-sealable layer and the laminates are connected together by heat sealing at a first temperature.    
     
     
         15 . (canceled)  
     
     
         16 . The method according to  claim 14  wherein the second laminate comprises a heat-sealable layer and the second laminate is sealed to itself or to another similar laminate by heat seating at a second temperature lower than the first temperature.  
     
     
         17 . The method according to  claim 14 , wherein the first laminate comprises first and second surfaces, the first surface being provided with a water retaining layer and the second surface being connected to the second laminate.  
     
     
         18 . The method according to  claim 14 , further comprising dividing the first and third laminates into sections prior to connecting to the second laminate.  
     
     
         19 . (canceled)  
     
     
         20 . The method according to  claim 14 , further comprising forming louvers in the first laminate prior to connecting it to the second laminate.  
     
     
         21 . A heat exchange element comprising a membrane comprising a formable laminate of a metal layer and a heat-seal layer, the membrane being provided on first and second surfaces with a plurality of generally corrugated fins, the fins comprising a formable laminate of a metal layer and a heat-seal layer and being connected under heat and pressure in heat conducting relationship with the membrane to increase an effective surface area thereof, the membrane being folded to form flow channels for first and second heat exchange media to flow over its respective first and second surfaces, the heat exchange element further comprising a water-retaining layer provided on the fins on at least the second surface.  
     
     
         22 . The heat exchange element according to  claim 21 , wherein the water retaining layer is a fibrous non-woven material adhesively laminated to the fins.  
     
     
         23 . The heat exchange element according to  claim 21 , further comprising louvers formed through the fins.  
     
     
         24 . The beat exchange element according to  claim 1 , further comprising louvers formed trough the fins.