Flexible metallic heat connector

Abstract

A thermal connector configured to be placed within a recess of a heat sink between the heat sink and a heat generating component and transfer heat from the component to the heat sink, including a heat spreader configured to fit within the recess of the heat sink, a spring configured to sit between the heat spreader and with the heat sink and bias the heat spreader towards and away from the heat sink, a flexible membrane attached to the heat sink and the heat spreader and seal off the recess, and a phase change material that fills the recess, wherein the flexible membrane contains the phase change material and allows it to contract or expand in response to the movement of the heat spreader towards or away from the heat sink.

1 . A thermal connector, comprising:
 a heat sink;   a heat spreader; and   a spring, positioned between, and in contact with, the heat spreader and the heat sink, wherein the spring is held compressed to its smallest height by a phase change material so that when the phase material is melted, the heat spreader is pushed by the spring away from the heat sink and into contact with a heat generating component positioned adjacent to the heat sink.   
     
     
         2 . The thermal connector according to  claim 1 , wherein the spring comprises a body portion that is connected flush with the heat spreader and a plurality of legs angled away from the heat spreader and towards the heat sink so that the plurality of legs contact the heat sink. 
     
     
         3 . The thermal connector according to  claim 1 , further comprising a flexible membrane attached to the heat sink and the heat spreader that contains the phase change material. 
     
     
         4 . The thermal connector according to  claim 1 , wherein the flexible membrane is a silicone or urethane polymer. 
     
     
         5 . The thermal connector according to  claim 1 , wherein the phase change material is a low melting alloy. 
     
     
         6 . The thermal connector according to  claim 5 , wherein the low melting alloy has a melting point of about 118° C. and a thermal conductivity of about 35 W/mK. 
     
     
         7 . The thermal connector according to  claim 1 , wherein the phase change material has a melting point between about 40° C. to 250° C. and a thermal conductivity between about 20 W/mK and 400 W/mK. 
     
     
         8 . The thermal connector according to  claim 1 , wherein the phase change material has a melting point between about 60° C. to 160° C. and a thermal conductivity between about 30 W/mK and 100 W /mK. 
     
     
         9 . The thermal connector according to  claim 1 , wherein the heat generating component is an electrical device component. 
     
     
         10 . The thermal connector according to  claim 1 , wherein the spring biases the heat spreader within a range of 0.1 mm to 3 mm. 
     
     
         11 . A method for thermally connecting a heat generating component and a heat sink that are separated by a tolerance, the method comprising:
 providing a thermal connector comprised of:
 a heat spreader, and 
 a spring connected to the heat spreader that is held compressed at its smallest height by a phase change material; 
   placing the thermal connector in the tolerance between the heat generating component and the heat sink; and   heating the phase change material to a melting temperature to allow the spring to push the heat spreader away from the heat sink and into contact with the heat generating component.   
     
     
         12 . The method according to  claim 11 , wherein the spring comprises a body portion that is connected flush with the heat spreader and a plurality of legs angled away from the heat spreader and towards the heat sink so that the plurality of legs contact the heat sink. 
     
     
         13 . The method according to  claim 11 , wherein the thermal connector further comprises a flexible membrane attached to the heat sink and the heat spreader that contains the phase change material. 
     
     
         14 . The method connector according to  claim 11  wherein the flexible membrane is a silicone or urethane polymer. 
     
     
         15 . The method according to  claim 1 , wherein the phase change material is a low melting alloy. 
     
     
         16 . The method according to  claim 15 , wherein the low melting alloy has a melting point of about 118° C. and a thermal conductivity of about 35 W/mK. 
     
     
         17 . The method according to  claim 11 , wherein the phase change material has a melting point between about 40° C. to 250° C. and a thermal conductivity between about 20 W/mK and 400 W/mK. 
     
     
         18 . The method according to  claim 11 , wherein the phase change material has a melting point between about 60° C. to 160° C. and a thermal conductivity between about 30 W/mK and 100 W /mK. 
     
     
         19 . The method according to  claim 11 , wherein the tolerance is within a range of 0.1 mm to 3 mm. 
     
     
         20 . A method for assembling a thermal connector, the method comprising:
 providing the thermal connector comprised of:
 a heat spreader and a spring, the spring comprising a body portion that is connected flush with the heat spreader and a plurality of legs angled away from the heat spreader; 
 a low melting point alloy surrounding the spring, wherein (i) when the alloy is in a melted state, the spring may move the heat spreader, and (ii) when the alloy is in a hardened state, the spring may not move the heat spreader; 
 a flexible membrane that contains the low melting point alloy within the gap and allows the alloy to contract and expand in response to the movement of the heat spreader towards and away from the heat sink; 
   melting the alloy to a melted state;   compressing the spring to its smallest height;   cooling the alloy to a hardened state to hold the spring in compression.