Liquid cooling system

Abstract

Embodiments of the present disclosure may include a liquid cooling system in which an inlet hole and an outlet hole that are located at both ends of a circulating flow passage opened onto a heat-radiating sheet having the circulating flow passage between a pair of heat-conductive metal plates that are superimposed on each other, a pump having a discharge port and a suction port that communicate with the inlet hole and the outlet hole installed on the heat-radiating sheet, a heat-generating element set on the heat-radiating sheet via a heat spreader, and used as a heat-receiving area, and the circulating flow passage having a heat-absorbing flow passage located in a lower face of the heat spreader and a heat-radiating flow passage located in the heat-radiating area other than the heat spreader and having a sufficiently larger length than the flow passage length of the heat-absorbing flow passage.

1 . A liquid cooling system comprising:
 a heat-radiating sheet having a pair of heat-conductive metal plates that are superimposed on each other, and having a circulating flow passage between the pair of heat-conductive metal plates;   an inlet hole and an outlet hole opened to the surface of the heat-radiating sheet and located at both ends of the circulating flow passage;   a pump having a discharge port and a suction port that communicate with the inlet hole and the outlet hole, and installed on the heat-radiating sheet;   a heat-receiving area and a heat-radiating area set on the heat-radiating sheet; and   a heat-generating element installed on the heat-receiving area via a heat spreader made of a heat-conductive material,   wherein the circulating flow passage has a heat-absorbing flow passage located in a lower face of the heat spreader of the heat-receiving area, and a heat-radiating flow passage located in the heat-radiating area and having a sufficiently larger length than the flow passage length of the heat-absorbing flow passage.   
   
   
       2 . The liquid cooling system of  claim 1 , wherein the flow passage length of the heat-radiating flow passage is  10  or more times the flow passage length of the heat-absorbing flow passage. 
   
   
       3 . The liquid cooling system of  claim 1 , wherein the heat-absorbing flow passage has a main heat-absorbing flow passage located directly below the heat-generating element, and at least one heat-absorbing U-shaped flow passage adjacent to the main heat-absorbing flow passage. 
   
   
       4 . The liquid cooling system of  claim 3 , wherein the heat-radiating flow passage from the heat-absorbing U-shaped flow passage to the heat-radiating area has a heat-radiating reciprocating flow passage that reciprocates multiple-times in the heat-radiating area before returning again to the heat-absorbing area. 
   
   
       5 . The liquid cooling system of  claim 3 , wherein the main heat-absorbing flow passage is one in an inlet and an outlet, and is branched into a plurality of flow passages directly below a heat-generating source. 
   
   
       6 . The liquid cooling system of  claim 3 , wherein the main heat-absorbing flow passage is connected to an outermost peripheral heat-radiating flow passage that returns to the outlet hole through the outermost periphery of the heat-radiating sheet after passing through the main heat-absorbing flow passage. 
   
   
       7 . The liquid cooling system of  claim 1 , wherein the area of the heat-radiating sheet is  10  or more times the area of the heat spreader. 
   
   
       8 . The liquid cooling system of  claim 1 , wherein the inlet hole and outlet hole of the circulating flow passage are formed as tubular projections in the heat-radiating sheet, and the discharge port and suction port of the pump are formed as a discharge port that communicates with the tubular projection serving as the inlet hole, and a suction port that communicates with the tubular projection serving as the outlet hole. 
   
   
       9 . The liquid cooling system of  claim 1 , wherein the pump is a piezoelectric pump. 
   
   
       10 . The liquid cooling system of  claim 1 , wherein a spacer block is interposed between the pump and the heat-radiating sheet, and the spacer block is formed with a liquid injection hole extending to the circulating flow passage. 
   
   
       11 . The liquid cooling system of  claim 1 , wherein the heat-generating source is a CPU of a notebook computer, and the whole liquid cooling system is received inside a main body having a keyboard. 
   
   
       12 . The liquid cooling system of  claim 11 , wherein the heat-radiating sheet of the liquid cooling system is provided along the surface of the keyboard.