Heat sink

Abstract

A heat sink absorbs heat from a chip or other component ( 32 ) and transfers the heat to a cooling fluid ( 36 ). The sink has a shaped part ( 22 ″) on which are formed at least one element ( 56 ″) for supplying cooling fluid ( 36 ) and at least one element ( 62 ″) for removing cooling fluid ( 36 ). The heat sink has a heat absorber ( 68 ″) with a heat-absorption side ( 112 u ) that absorbs heat during operation and a heat-transfer side ( 78 ) in contact with the cooling fluid ( 36 ) during operation. The absorber has a depression ( 118 ) in which are arranged a plurality of elongated thermally conductive elements ( 84 ″) which are each connected at a first end to the depression ( 118 ), and each have a free end ( 78 ) projecting away from the depression ( 118 ). Optionally, the heat sink can be coupled to a radiating or cooling unit ( 38 ), a fluid-circulating pump ( 39 ) and a fan ( 40 ) for directing air over the cooling unit, in order to quickly dissipate the heat transferred to the cooling fluid ( 36 ).

1 . A heat sink for absorbing heat from a component ( 32 ) and for removing heat by means of a cooling fluid ( 36 ), said heat sink comprising: 
 a supply element ( 56 ) for supplying cooling fluid ( 36 ) to the heat sink;    a removal element ( 62 ,  63 ) for removing cooling fluid ( 36 ) from the heat sink;    a heat absorber ( 68 ;  68 ′;  68 ″) in which one side is implemented for the absorption of heat and another side ( 78 ), in contact with the cooling fluid ( 36 ) during operation, is formed with a depression ( 82 ;  82 ′;  82 ″) having depths ranging from a shallowest region to a deepest region, in which depression are arranged a plurality of thermally conductive elements ( 84 ), each having a fixed end and a free end, and which are connected in thermally conductive fashion, at their ends adjacent the depression ( 82 ;  82 ′;  82 ″), to the bottom of that depression ( 82 ), and whose free ends ( 78 ) project outwardly with respect to the depression ( 82 ;  82 ′;  82 ″);    the supply element ( 56 ) being configured in order, during operation, to deliver cooling fluid to the depression ( 82 ;  82 ′;  82 ″) in the vicinity of its deepest region,    the supply element being formed, for delivery purposes, with at least one exit opening ( 58 ) that is arranged at a predetermined minimum distance from the free ends ( 78 ) of the thermally conductive elements ( 84 ).    
   
   
       2 . The heat sink according to  claim 1 , 
 wherein a nozzle field ( 59 ;  59 ′;  59 ″) is arranged adjacent an outlet of the cooling fluid ( 36 ) from the supply element ( 56 ).    
   
   
       3 . The heat sink according to  claim 2 , 
 wherein said nozzle field comprises a plurality of round nozzles ( 58 ″) that have a predetermined diameter (D) and the nozzle field ( 59 ;  59 ′;  59 ″) is at a distance (h) from the bottom ( 82 ″) of the depression that is greater than said predetermined diameter (D).    
   
   
       4 . The heat sink according to  claim 3 , 
 wherein said distance (h) is within a range between two times said diameter and three times said diameter (D).    
   
   
       5 . The heat sink according to  claim 2 , wherein the nozzle field ( 59 ′) comprises slit-shaped nozzles ( 58 ′).  
   
   
       6 . The heat sink according to  claim 2 , wherein said nozzle field ( 59 ′) comprises a plurality of parallel-aligned nozzles.  
   
   
       7 . The heat sink according to  claim 1 , wherein the depression ( 82 ) has the shape of a calotte.  
   
   
       8 . The heat sink according to  claim 1 , wherein the depression ( 82 ) has a shape defined by a rotated conic section.  
   
   
       9 . The heat sink according to  claim 1 , wherein each thermally conductive element ( 84 ) has a respective shape selected from the group consisting of a pin, a rib and a column.  
   
   
       10 . The heat sink according to  claim 1 , 
 wherein, to facilitate egress of cooling fluid ( 64 ) heated, during operation, adjacent said depression ( 82 ;  82 ′;  82 ″), there is provided, around said depression, an annular conduit ( 92 ,  122 ) that is connected to an outflow element ( 62 ,  63 ,  62 ″) for the cooling fluid.    
   
   
       11 . The heat sink according to  claim 1 , further comprising 
 a housing part ( 22 ), wherein said heat absorber ( 68 ), formed with said depression ( 82 ;  82 ′;  82 ″), is arranged in an opening ( 46 ) of said housing part ( 22 ), and is sealed with respect to said housing part by at least one sealing member ( 74 ).    
   
   
       12 . The heat sink according to  claim 11 , 
 wherein said supply element ( 56 ) and at least one outflow element ( 62 ,  63 ) are arranged in said housing part ( 22 ).    
   
   
       13 . The heat sink according to  claim 11 , wherein said housing part ( 22 ) is implemented as an injection-molded part.  
   
   
       14 . The heat sink according to  claim 1 , wherein at least one surface that is, during operation, in contact with the cooling fluid is roughened to facilitate heat transfer.  
   
   
       15 . The heat sink according to  claim 1 , wherein 
 there is provided, opposite the thermally conductive elements ( 84 ) arranged in the depression ( 82 ;  82 ′;  82 ″), at least one flow-directing element ( 52 ) that, in coaction with the thermally conductive elements ( 84 ), defines, for said cooling fluid ( 36 ), different flow resistances at different points of the heat absorber ( 68 ).    
   
   
       16 . The heat sink according to  claim 15 , 
 wherein the flow-directing element ( 52 ) is ring-shaped.    
   
   
       17 . The heat sink according to  claim 16 , wherein 
 the ring ( 52 ) is arranged around a supply opening for the cooling fluid ( 36 ).    
   
   
       18 . The heat sink according to  claim 15 , 
 wherein the at least one flow-directing element ( 52 ) comprises a chamfer ( 53 ) along at least one portion thereof, in order to influence resistance to flow of said fluid.    
   
   
       19 . The heat sink according to  claim 15 , wherein 
 the at least one flow-directing element ( 52 ) is formed, at at least one point, with a protrusion ( 100 ) that projects between free ends ( 78 ) of two adjacent thermally conductive elements ( 84 ).    
   
   
       20 . The heat sink according to  claim 1 , wherein 
 said supply element ( 56 ) is aligned centrally with respect to said heat absorber, in order to supply cooling fluid ( 36 ) to the heat absorber ( 68 ) approximately in its center; and    at least one outflow element ( 62 ,  63 ) opens at a periphery ( 90 ,  122 ) of said depression ( 82 ;  82 ′;  82 ″).    
   
   
       21 . The heat sink according to  claim 20 , wherein 
 a plurality of outflow elements ( 62 ,  63 ) are provided, arranged substantially symmetrically with respect to the supply element ( 56 ), in order to bring about, during operation, a substantially symmetrical flow of cooling fluid ( 36 ) across the heat absorber ( 68 ).    
   
   
       22 . A heat sink for absorbing heat from a component ( 32 ) and for removing heat by means of a cooling fluid ( 36 ), said heat sink comprising: 
 at least one supply element ( 56 ) for supplying cooling fluid ( 36 ) to the heat sink;    at least one removal element ( 62 ,  63 ) for removing cooling fluid ( 36 ) from the heat sink;    a heat absorber ( 68 ;  68 ′;  68 ″) in which one side is implemented for the absorption of heat and another side ( 78 ), in contact with the cooling fluid ( 36 ) during operation, is formed with a depression ( 82 ;  82 ′;  82 ″), in which are arranged a plurality of thermally conductive elements ( 84 ;  84 ′;  84 ″) which are connected in thermally conductive fashion, at their ends adjacent the depression ( 82 ;  82 ′;  82 ″), to the bottom of that depression ( 82 ;  82 ′;  82 ″), and whose free ends ( 78 ) project away from the depression ( 82 );    the at least one supply element ( 56 ) being configured in order, during operation, to deliver cooling fluid to the depression ( 82 ;  82 ′;  82 ″) in its deepest region,    the supply element being formed, for delivery purposes, with at least one exit opening ( 58 ) that is arranged at a predetermined minimum distance from the free ends ( 78 ) of the thermally conductive elements ( 84 );    there being arranged, in the region of the exit opening, a nozzle field ( 59 ;  59 ′;  59 ″) having nozzles ( 58 ″) which are arranged so that a stream ( 36 ″) of cooling fluid exiting from a nozzle ( 58 ″) is directed onto a valley ( 82 ″ cr ) between two adjacent thermally conductive elements ( 84 ″).    
   
   
       23 . The heat sink according to  claim 22 , 
 wherein the width (d) of the valleys ( 82 ″ h ,  82 ″ v ) falls within a range from 0.2 to 0.4 mm.    
   
   
       24 . The heat sink according to  claim 23 , 
 wherein a nozzle ( 58 ″) is arranged so that a stream ( 36 ″) of cooling fluid exiting from it is directed onto a location ( 82 ″ cr ) between four adjacent thermally conductive elements ( 84 ″).    
   
   
       25 . The heat sink according to  claim 22 , wherein the thermally conductive elements ( 84 ;  84 ′;  84 ″) are shaped like needles, which have an average cross section and are separated from one another by depressions in the form of valleys ( 82 ″ h ,  82 ″ v ) whose inside width (d) is within a range defined by  
         d =(0.25 . . . 0.5)* exp (0.5 *lnQ ),  where    d=inside width of a valley in millimeters,    Q=average cross section of a thermally conductive element ( 84 ″) in square millimeters;    ln=natural logarithm or base-e logarithm.    
   
   
       26 . The heat sink according to  claim 22 , 
 wherein the nozzle field ( 59 ;  59 ′;  59 ″) is at a distance (h) from the bottom ( 82 ″) of the depression that, in the context of round nozzles ( 58 ″) that have a predetermined diameter (D), is greater than that diameter (D).    
   
   
       27 . The heat sink according to  claim 26 , 
 wherein that distance (h) falls within a range between two times that diameter (D) and three times that diameter (D).    
   
   
       28 . The heat sink according to  claim 22 , wherein the nozzle field ( 59 ′) comprises slit-shaped nozzles ( 58 ′).  
   
   
       29 . The heat sink according to  claim 22 , wherein the depression ( 82 ) has the shape of a calotte.  
   
   
       30 . The heat sink according to  claim 22 , wherein the depression ( 82 ) has a shape defined by a rotated conic section.  
   
   
       31 . The heat sink according to  claim 22 , wherein each thermally conductive element ( 84 ) has a respective shape selected from the group consisting of a pin, a rib and a column.  
   
   
       32 . The heat sink according to  claim 22 , 
 wherein, to facilitate egress of cooling fluid ( 64 ) heated, during operation, adjacent said depression ( 82 ;  82 ′;  82 ″), there is provided, around said depression, an annular conduit ( 92 ,  122 ) that is connected to an outflow element ( 62 ,  63 ,  62 ″) for the cooling fluid.    
   
   
       33 . The heat sink according to  claim 22 , further comprising 
 a housing part ( 22 ) formed with an opening ( 46 ), said heat absorber ( 68 ) being arranged in said opening ( 46 ) and being sealed with respect to said opening by at least one sealing member ( 74 ).    
   
   
       34 . The heat sink according to  claim 33 , further comprising at least one supply fitting ( 56 ) and at least one outflow element ( 62 ,  63 ) arranged in said housing part ( 22 ).  
   
   
       35 . The heat sink according to  claim 33 , wherein said housing part ( 22 ) is formed by injection-molding.  
   
   
       36 . The heat sink according to  claim 22 , 
 wherein there is provided, opposite the thermally conductive elements ( 84 ) arranged in the depression ( 82 ;  82 ′;  82 ″),    at least one flow-directing element ( 52 ) that, in coaction with the thermally conductive elements ( 84 ), defines for said cooling fluid ( 36 ) different flow resistances at different points of the heat absorber ( 68 ).    
   
   
       37 . The heat sink according to  claim 36 , 
 wherein said flow-directing element ( 52 ) is arranged around a supply opening for the cooling fluid ( 36 ).    
   
   
       38 . The heat sink according to  claim 36 , wherein 
 the at least one flow-directing element ( 52 ) comprises a chamfer ( 53 ) along at least one portion thereof, in order to influence resistance to flow of said fluid.    
   
   
       39 . The heat sink according to  claim 36 , 
 wherein the at least one flow-directing element ( 52 ) is formed with a protrusion ( 100 ) that projects between the free ends ( 78 ) of two adjacent thermally conductive elements ( 84 ).    
   
   
       40 . The heat sink according to  claim 22 , wherein 
 said supply element ( 56 ) is aligned centrally with respect to said heat absorber, in order to supply cooling fluid ( 36 ) to the heat absorber ( 68 ) approximately in its center; and    at least one outflow element ( 62 ,  63 ) opens at a periphery ( 90 ,  122 ) of said depression ( 82 ;  82 ′;  82 ″).    
   
   
       41 . The heat sink according to  claim 40 , 
 wherein a plurality of outflow elements ( 62 ,  63 ) are provided which are arranged substantially symmetrically with respect to the supply element ( 56 ) in order to bring about, during operation, a substantially symmetrical flow of cooling fluid ( 36 ) in the heat absorber ( 68 ).    
   
   
       42 . The heat sink according to  claim 22 , 
 wherein the heat absorber ( 68 ″) comprises at least one protrusion ( 110 ,  112 ) projecting away from the supply element ( 22 ″),    and a supporting part ( 114 ) is provided that is mechanically joined to the supply element ( 22 ″) and mechanically supports the heat absorber ( 68 ″) in a region outside that protrusion ( 110 ,  112 ).    
   
   
       43 . A heat sink for absorbing heat from a component ( 32 ) and for removing heat by means of a cooling fluid ( 36 ), 
 which heat sink comprises:    a shaped part ( 22 ″) on which are provided at least one supply element ( 56 ″) for supplying cooling fluid ( 36 ) and at least one removal element ( 62 ″) for removing cooling fluid ( 36 );    a heat absorber ( 68 ″) having a heat-absorption side ( 112   u ) which, in operation, serves to absorb heat, and a cooling-fluid side ( 78 ) that is in contact with the cooling fluid ( 36 ) during operation and is formed with a depression ( 118 ), in which are arranged a plurality of thermally conductive elements ( 84 ″) that are connected in thermally conductive fashion, at their ends facing toward the depression ( 118 ), to that depression ( 118 ), and whose free ends ( 78 ) project away from the depression ( 118 );    at least one protrusion ( 110 ,  112 ), provided on the heat-absorption side of the heat absorber ( 68 ″), into which protrusion the depression ( 118 ) extends from the cooling-fluid side; and    a retaining member ( 114 ) which comprises a recess ( 115 ) into which the at least one protrusion ( 110 ,  112 ) of the heat absorber ( 68 ″) projects,    and which is joined to the shaped part ( 22 ″) in order to secure the heat absorber ( 68 ″) on the shaped part ( 22 ″).    
   
   
       44 . The heat sink according to  claim 43 , wherein 
 the shaped part ( 22 ″) comprises a recess ( 46 ″) into which the heat absorber ( 68 ″) projects, at least one sealing member ( 74 ″) being provided between the heat absorber ( 68 ″) and the recess ( 46 ″).    
   
   
       45 . The heat sink according to  claim 43 , 
 wherein said depression ( 118 ) formed in the heat absorber ( 68 ″) extends through the recess ( 115 ) of the retaining member ( 114 ) and is closed off, in liquid-tight fashion,    by the heat-absorption side ( 112   u ) of the heat absorber ( 68 ″).    
   
   
       46 . The heat sink according to  claim 43 , 
 wherein the shaped part ( 22 ″) is provided with attachment recesses ( 117 ) that comprise hollow extensions ( 117 A) which project beyond the retaining member ( 114 ) and its attachment elements ( 116 ).    
   
   
       47 . The heat sink according to  claim 46 , 
 wherein the attachment recesses ( 117 ) are provided at least partially on lateral protrusions ( 119 ) of the shaped part ( 22 ″).    
   
   
       48 . The heat sink according to  claim 43 , wherein said depression has a generally concave shape.