Heat carrier

• US 6,530,420 B1
• Filed: 09/14/2000
• Issued: 03/11/2003
• Est. Priority Date: 09/17/1999
• Status: Expired due to Fees

• Current Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Inventors: Oki, Katsuyoshi, Takada, Tomohito, Nasako, Kenji, Yamamoto, Yasushi, Hiro, Naoki
• Primary Examiner(s): Bennett, Henry
• Assistant Examiner(s): MCKINNON, TERRELL L
• Application Number:
  US09/662,330
• Time in Patent Office: 908 Days
• Field of Search: 165/104.26, 165/104.33, 165/80.4, 165/185, 361/699, 361/700, 257/715, 174/15.2
• US Class Current: 165/104.33
• CPC Class Codes: C09K 5/04 the change of state being from liquid to vapour or vice versa
• CPC Class Codes: F24S 10/95 having evaporator sections and condenser sections, e.g. heat pipes
• CPC Class Codes: F25B 2309/061 with cycle highest pressure above the supercritical pressure
• CPC Class Codes: F28D 15/02 in which the medium condenses and evaporates, e.g. heat pipes heat pipes used in solar heat collectors F24S10/95; in radiators F28D1/0226; in nuclear reactors G21C15/257
• CPC Class Codes: F28D 15/0266 with separate evaporating and condensing chambers connected by at least one conduit; Loop-type heat pipes; with multiple or common evaporating or condensing chambers F28D15/043 takes precedence
• CPC Class Codes: G06F 1/203 for portable computers, e.g. for laptops
• CPC Class Codes: H05K 7/20336 Heat pipes, e.g. wicks or capillary pumps
• CPC Class Codes: Y02E 10/40 Solar thermal energy, e.g. solar towers
• CPC Class Codes: Y02E 10/44 Heat exchange systems
• CPC Class Codes: Y02P 20/54 using solvents, e.g. supercritical solvents or ionic liquids

Abstract

A heat carrier comprises a closed or looped heat pipe having a heat receiving section and a heat radiating section, and accommodating therein a heating medium such as carbon dioxide, which becomes a low-viscous supercritical fluid when it is heated. The supercritical fluid is circulated in the heat pipe by convection due to a density difference based on a temperature difference between the heat receiving section and the heat radiating section, thereby carrying heat from the heat receiving section to the heat radiating section.

Claims

1. A heat carrier comprising:

a closed container for accommodating therein a heating medium, said container having at least one heat receiving section and at least one heat radiating section, wherein

said heating medium is transformed into a supercritical fluid when it is heated and undergoes convection due to a difference in temperature between said heat receiving section and said heat radiating section, thereby carrying heat from said heat receiving section to said heat radiating section;

wherein said container is a looped pipe connecting said heat receiving section and said heat radiating section;

wherein said looped pipe in said heat receiving section(s) has a planar mesh configuration; and

wherein said looped pipe has a smaller diameter in said heat receiving section(s) as compared with the rest of said pipe;

whereby a heat transfer between the heat receiving section and the heat radiating section is desirably balanced.

2. The heat carrier according to claim 1, wherein said heating medium is carbon dioxide.

3. The heat carrier according to claim 1, wherein said looped pipe is provided with at least one upward bend.

4. The heat carrier according to claim 1, wherein said looped pipe is covered with a heat insulator except at said heat receiving section and said heat radiating section.

5. The heat carrier according to claim 1, wherein said looped pipe has more than one heat radiating section.

6. The heat carrier according to claim 1, wherein said looped pipe is provided with more than one heat receiving section and one heat radiating section.

7. The heat carrier according to claim 1, wherein said looped pipe in said heat receiving section(s) is disposed along the profile of an object that includes the heat receiving section(s).

8. The heat carrier according to claim 7, wherein said heating medium is carbon dioxide.

9. The heat carrier according to claim 7, wherein the object is a printed circuit board, whereby the heat receiving section(s) cools a multiplicity of heat generating elements on the printed circuit board.

10. The heat carrier according to claim 1, comprising in combination the heat carrier and a notebook computer;

the notebook computer comprising a CPU and a display;

the heat carrier comprising;

a closed container for accommodating therein a heating medium, said container having at least one heat receiving section and at least one heat radiating section, wherein

said heating medium is transformed into a supercritical fluid when it is heated and undergoes convection due to a difference in temperature between said heat receiving section and said heat radiating section, thereby carrying heat from said heat receiving section to said heat radiating section;

wherein said container is a looped pipe connecting said heat receiving section and said heat radiating section; and

wherein said at least one heat receiving section is in thermal contact with the CPU and said at least one heat radiating section is in thermal contact with the display.

11. The heat carrier according to claim 1, wherein the heat radiating section is diposed around a border of the display.

12. A heat carrier comprising:

a closed container for accommodating therein a heating medium, said container having at least one heat receiving section and at least one heat radiating section, wherein

said heating medium is transformed into a supercritical fluid when it is heated and undergoes convection due to a difference in temperature between said heat receiving section and said heat radiating section, thereby carrying heat from said heat receiving section to said heat radiating section;

wherein said container is a looped pipe connecting said heat receiving section and said heat radiating section;

wherein said heat receiving section is at a lower level than said heat radiating section; and

wherein said heat radiating section further includes a portion zigzagging between said heat receiving section and said heat radiating section.

13. The heat carrier according to claim 12, wherein said heating medium is carbon dioxide.