Heat-pipe system and method of and apparatus for controlling a flow rate of a working fluid in a liquid pipe of the heat pipe system

Claim 1

A heat-pipe system which comprises: an evaporator having a first capillary structure for evaporating a working fluid; a condenser having a second capillary structure for condensing vapor evaporated in said evaporator into liquid condensate so as to return it to the evaporator through a liquid duct; a vapor transport pipe communicating between vapor channels of said evaporator and said condenser for transporting the vapor evaporated in the evaporator; a pump provided at the liquid duct for driving the working fluid therethrough; sensor means for detecting the change in the amount of liquid in the capillary structure of the evaporator in accordance with the pressure difference between vapor pressure in the vapor channel and liquid pressure in the liquid channel of the evaporator; and control unit means having a CPU, a ROM, and a RAM, connected between said pump and said sensor means for controlling the rotational speed of the pump in accordance with a detected signal from said sensor means so as to optimally control the amount of the liquid remaining in the capillary structure of the evaporator by controlling a flow rate of the liquid flowing through the liquid duct.

Claim 5

A method of controlling a flow rate of a working fluid in a liquid duct of a heat-pipe system, paticularly an arterial heat-pipe system having evaporator and condenser, which comprises the steps of: detecting the position of interface between vapor and liquid in an elongated pipe of a sensor means for detecting the liquid amount; calculating P V -P L from the difference between capillary force Pcap in the elongated pipe of the sensor means and head height due to the self weight of the liquid in the elongated pipe (where P V =vapor pressure in the vapor channel and P L =liquid pressure in the liquid channel of the evaporator); determining if P V -P L <Pcap. max is found (where Pcap. max=maximum capillary force in the vapor channel of the evaporator); increasing the rotational speed of a pump provided at the liquid duct if the result of said determination is NO and repeating this operation until it reaches a desired result; determining if 0<P V -P L is found, in accordance with the result of said first determination, i.e., YES is found; decreasing the rotational speed of the pump if the result of the last determination is NO, i.e., 0≧P V -P L is found; and returning the operation to the first step of detecting the position of interface when the last determination is YES, that is, 0<P V -P L is found, thereby optimally controlling the amount of liquid remaining in the capillary structure of the evaporator.

Claim 6

A method of controlling a flow rate of a working fluid in a liquid duct of a heat-pipe system, paticularly an arterial heat-pipe system having evaporator and condenser, which comprises the steps of: detecting the position of interface between vapor and liquid in an elongated pipe of a sensor means for detecting the liquid amount; calculating P V -P L from the difference between capillary force Pcap in the elongated pipe of the sensor means and head height due to the self weight of the liquid in the elongated pipe (where P V =vapor pressure in the vapor channel and P L =liquid pressure in the liquid channel of the evaporator); determining if P V -P L <Pcap. max is found (where Pcap. max=maximum capillary force in the vapor channel of the evaporator); increasing the rotational speed of a pump provided at the liquid duct if the result of said determination is NO and repeating this operation until it reaches a desired result; determining if 0<P V -P L is found, in accordance with the result of said first determination, i.e., YES is found; decreasing the rotational speed of the pump if the result of the last determination is NO, i.e., 0≧P V -P L is found; and returning the operation to the first step of detecting the position of interface when the last determination is YES, that is, 0<P V -P L is found, thereby optimally controlling the amount of liquid remaining in the capillary structure of the evaporator.