Dew condensation detecting device, cooling system and cooling medium flow rate controlling method

Abstract

A dew condensation detecting device includes a dew condensation detector and a heat transfer part. The dew condensation detector is provided to a supply pipe, which supplies a cooling medium from a cooling medium supply apparatus to a device to be cooled. The dew condensation detector detects a dew condensation by detecting a water droplet due to the dew condensation. The heat transfer part transfers heat from the cooling medium flowing in a return pipe, which returns the cooling medium from the device to be cooled to the cooling medium supply apparatus, to the cooling medium flowing in the supply pipe between the dew condensation detector and the device to be cooled.

What is claimed is: 
     
         1 . A dew condensation detecting device, comprising:
 a dew condensation detector provided to a supply pipe, which supplies a cooling medium from a cooling medium supply apparatus to a device to be cooled, the dew condensation detector detecting a dew condensation by detecting a water droplet due to the dew condensation; and   a heat transfer part that transfers heat from the cooling medium flowing in a return pipe, which returns the cooling medium from said device to be cooled to said cooling medium supply apparatus, to the cooling medium flowing in said supply pipe between said dew condensation detector and said device to be cooled.   
     
     
         2 . The dew condensation detecting device as claimed in  claim 1 , wherein said heat transfer part includes a heat transfer member that contacts with said supply pipe and said return pipe. 
     
     
         3 . The dew condensation detecting device as claimed in  claim 2 , wherein said heat transfer member is a metal material that is joined to said supply pipe and said return pipe. 
     
     
         4 . The dew condensation detecting device as claimed in  claim 1 , wherein said heat transfer part includes a coupling cover and a heat transfer material, the coupling cover having a loop form to surround said supply pipe and said return pipe, the heat transfer material being filled in a space between said supply pipe and said return pipe. 
     
     
         5 . The dew condensation detecting device as claimed in  claim 4 , wherein said heat transfer material includes a thermal sheet or a thermal compound. 
     
     
         6 . The dew condensation detecting device as claimed in  claim 1 , wherein said heat transfer part includes a coupling pipe that supplies a part of the cooling medium flowing in said return pipe to said supply pipe. 
     
     
         7 . The dew condensation detecting device as claimed in  claim 6 , wherein one end of said coupling pipe is inserted into said return pipe and the other end of said coupling pipe is inserted into said supply pipe, the one end of said coupling pipe being provided with a flow-in opening through which the cooling medium flows into said coupling pipe, the other end of said coupling pipe being provided with a flow-out opening from which the cooling medium flows out of said coupling pipe. 
     
     
         8 . The dew condensation detecting device as claimed in  claim 6 , wherein one end of said coupling pipe is inserted into and opens in said return pipe and the other end of said coupling pipe is inserted into and opens in said supply pipe, and an inclination plate is provided to each of said one end and said the other end of said coupling pipe. 
     
     
         9 . The dew condensation detecting device as claimed in  claim 1 , further comprising a heating part provided to said supply pipe between said dew condensation detector and said device to be cooled. 
     
     
         10 . The dew condensation detecting device as claimed in  claim 9 , wherein said heating part includes an electric heater. 
     
     
         11 . A cooling system, comprising:
 a device to be cooled that incorporates an internal part to be cooled by a cooling medium;   a cooling medium supply apparatus that creates the cooling medium supplied to said device to be cooled;   a supply pipe that connects said device to be cooled to said cooling medium supply apparatus in order to supply the cooling medium from said cooling medium supply apparatus to said device to be cooled;   a return pipe that connects said device to be cooled to said cooling medium supply apparatus in order to return the cooling medium from said device to be cooled to said cooling medium supply apparatus;   a dew condensation detector provided in a middle of said supply pipe; and   a heat transfer part that transfers heat from the cooling medium flowing in a return pipe to the cooling medium flowing in said supply pipe between said dew condensation detector and said device to be cooled.   
     
     
         12 . The cooling system as claimed in  claim 11 , wherein said heat transfer part includes a heat transfer member that contacts with said supply pipe and said return pipe. 
     
     
         13 . The cooling system as claimed in  claim 11 , wherein said heat transfer part includes a coupling pipe that supplies a part of the cooling medium flowing in said return pipe to said supply pipe. 
     
     
         14 . A cooling medium flow rate controlling method for controlling a flow rate of a cooling medium supplied to a device to be cooled, the cooling medium flow rate controlling method comprising:
 detecting a temperature of the cooling medium discharged from said device to be cooled; and   comparing the detected temperature with a temperature threshold value and controlling the flow rate of the cooling medium supplied to said device to be cooled based on a result of the comparing.   
     
     
         15 . The cooling medium flow rate controlling method as claimed in  claim 14 , wherein said temperature threshold vale includes an upper limit threshold value and a lower limit threshold vale, and the controlling the flow rate includes:
 increasing the flow rate of the cooling medium supplied to said device to be cooled when the detected temperature is higher than the upper limit threshold value; and   decreasing the flow rate of the cooling medium supplied to said device to be cooled when the detected temperature is lower than the lower limit threshold value.   
     
     
         16 . The cooling medium flow rate controlling method as claimed in  claim 15 , wherein the controlling the flow rate includes:
 comparing the flow rate of the cooling medium supplied to said device to be cooled with a flow rate lower limit value when the detected temperature is lower than the lower limit threshold vale;   decreasing the flow rated of the cooling medium supplied to said device to be cooled when the flow rate of the cooling medium supplied to the device to be cooled is higher than or equal to said flow rate lower limit value; and   heating the cooling medium supplied to said device to be cooled at a position between a dew condensation detecting position and said device to be cooled when the flow rate of the cooling medium supplied to the device to be cooled is lower than said flow rate lower limit value.