Structure of micro-heat pipe

• US 5,219,020 A
• Filed: 08/15/1991
• Issued: 06/15/1993
• Est. Priority Date: 11/22/1990
• Status: Expired due to Term

• Current Assignee: TS Heatronics Co., Ltd.
• Original Assignee: Actronics Kabushiki Kaisha
• Inventors: Akachi, Hisateru
• Primary Examiner(s): DAVIS JR, ALBERT
• Application Number:
  US07/745,555
• Time in Patent Office: 670 Days
• Field of Search: 165/104.22, 165/104.14, 165/104.26, 165/104.29
• US Class Current: 165/104.26
• 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: F28D 2015/0225 Microheat pipes
• CPC Class Codes: F28F 2210/10 Particular layout, e.g. for uniform temperature distribution

Abstract

A structure of a heat pipe applicable to a heat transportation device is disclosed in which an elongate metallic capillary tube is formed having an inner diaeter sufficiently small to enable movement of a bi-phase compressible working fluid having a predetrmined quantity and sealed into the metallic capillary container in a filled and closed state, a plurality of heat receiving portions and heat radiating portions being on predetermined parts of the elongate metallic tube and alternatingly arranged thereat. Both terminals of the metallic elongate capillary tube are heretically sealed thereat or hermetically connected to form a loop-type flow passage of the bi-phase compressible working fluid. In addition, no flow direction limiting mechanism such as check valves is essentially eliminated.

Claims

1. A structure of a heat pipe, comprising:

a) a metallic elongate tube of continuous capillary dimension;

b) a predetermined bi-phase condensative working fluid having a predetermined quantity less than an internal volume of the metallic elongate tube, the metallic elongate tube having a small inner diameter sufficient to allow the bi-phase condensible working fluid to move in a flow passage of the metallic elongate tube in a state always filled and closed in the metallic tube container due to surface tension;

c) at least one heat receiving portion located on a first predetermined part of the metallic elongate tube; and

d) at least one heat radiating portion located on a second predetermined part of the metallic elongate tube, both heat receiving portion and heat radiating portion being alternatively disposed on the metallic tube.

2. A structure of the heat pipe as set forth in claim 1, wherein both terminals of the metallic elongate tube are connected to each other to form a continuous capillary loop-type flow passage.

3. A structure of the heat pipe as set forth in claim 2, wherein almost all parts of the loop-type capillary container are formed in zigzag fashions multiple turns or in spiral fashions of multiple turns and the heat receiving portion and heat radiating portion are mutually plural and wherein almost all heat receiving and heat radiating portions are located on predetermined parts of the metallic elongate tube of respective turns of almost all parts of zigzag forms or spiral forms.

4. A structure of the heat pipe as set forth in claim 3, wherein an internal surface of the metallic elongate tube is smoothly polished.

5. A structure of the heat pipe as set forth in claim 4, wherein a heat insulating portion linking one of the heat receiving portions and adjacent one of the heat radiating portions in the metallic elongate tube is formed of the metallic elongate tube having a sufficiently thick thickness as compared with that at the heat radiating and heat receiving portions or of the metallic tube made of a metallic material having a high Young'"'"'s modulus and high anti-creep characteristic.

6. A structure of the heat pipe as set forth in claim 5, wherein the heat insulating portion is coated with an insulating material.

7. A structure of the heat pipe as set forth in claim 6, wherein the bi-phase condensible working fluid is made of a fluid metal.

8. A structure of the heat pipe as set forth in claim 7, wherein a predetermined heat receiving portions group from among a plurality of heat receiving portion groups is introduced into a common steam generating chamber, these terminals thereof being open from the common steam generating chamber.

9. A structure of the heat pipe as set forth in claim 8, wherein the metallic elongate tube is formed having a multiple number of turns, bent portions of the multiple turned portions being formed as a common internal pressure valve or as a common internal pressure vessel, the terminal groups of the turns being open to the internal pressure valve or to the internal pressure vessel.

10. A structure of the heat pipe as set forth in claim 1, wherein both terminals of the metallic elongate tube are hermetically sealed.

11. A structure of the heat pipe as set forth in claim 10, wherein the metallic elongate tube is formed in a zigzag fashion having a multiple number of turns and wherein a predetermined part of each turned portion is constituted by the heat receiving portion and another predetermined part thereof is constituted by the radiating portion.

12. A structure of the heat pipe as set forth in claim 11, wherein the elongate tube has an inner diameter equal to or less than 1.2 millimeters and the metallic elongate tube is made of an oxygen-free copper.

13. A structure of a heat pipe according to claim 1, wherein the metallic elongate tube has a continuous inside diameter of less than about 4.0 mm, whereby nucleate boiling of the working fluid at the heat receiving portion causes axial vibration of the working fluid resulting in thermal transfer from the heat receiving portion to the heat radiating portion.

14. A structure of a heat pipe according to claim 1, wherein the metallic elongate tube has a continuous inside diameter of less than about 1.2 mm, whereby nucleate boiling of the working fluid at the heat receiving portion causes axial vibration of the working fluid resulting in thermal transfer from the heat receiving portion to the heat radiating portion.

15. A structure of a heat pipe, comprising:

a) a metallic elongate tube of continuous capillary dimension;

b) a predetermined bi-phase condensible working fluid having a predetermined quantity less than an internal volume of the metallic elongate tube, the metallic elongate tube having a small inner diameter sufficient to allow the bi-phase condensible working fluid to move in a flow passage of the metallic elongate tube in a state always filled and closed in the metallic tube container due to surface tension;

c) at least one heat receiving portion located on a first predetermined part of the metallic elongate tube; and

d) at least one heat radiating portion located on a second predetermined part of the metallic elongate tube, both heat receiving portion and heat radiating portion being alternatively disposed on the metallic tube, whereby nucleate boiling of the working fluid at the heat receiving portion causes axial vibration of the working fluid resulting in thermal transfer from the heat receiving portion to the heat radiating portion without the need of check valves to control circulation of working fluid.