JP2011094822A - Loop-type heat pipe and electronic device including the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a loop-type heat pipe and an electronic device including the same, superior in starting performance and a heat transporting capacity. <P>SOLUTION: This loop type heat pipe 10 includes: a compensation chamber 11 for storing working liquid 18; an evaporating section 12 receiving heat from the external and evaporating the working liquid 18; a steam pipe 13 for guiding the steam of the evaporating section 12 to a condensing section 14; the condensing section 14 radiating heat to the external and condensing the steam; a liquid pipe 15 for guiding the condensed working liquid 18 to the compensation chamber 11; and a wick 22 partitioning a working liquid flow channel 22b communicated with the compensation chamber 11 and a steam flow channel 22b communicated with the steam pipe 13 in the evaporating section 12. In the loop type heat pipe 10, a spacer 16 is disposed movably between the compensation chamber 11 and the working liquid flow channel 22b, and moved into the working liquid flow channel 22b to reduce a volume of the working liquid flow channel 22b when the heat pipe is disposed in a state that a position of the evaporating section 12 is higher than a position of the condensing section 14. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a loop heat pipe used for cooling a heating element or the like and an electronic apparatus including the same.

  In recent years, the heat generation amount and heat generation density of electronic devices such as computers have increased, and improvement in cooling performance has been demanded. For this reason, a method is widely used in which a heat sink is disposed in a location suitable for cooling, such as in the vicinity of a cooling fan, and an electronic component having a large amount of heat, such as a CPU, and the heat sink are thermally connected by a heat pipe. Conventionally, as a heat pipe for thermally connecting a heat sink and an electronic component, a single-tube heat pipe having a simple structure has been used. However, the heat transport capacity of the single-tube heat pipe is as low as about 30 to 50 W, and may not be sufficient for cooling the electronic device. On the other hand, loop type heat pipes have better heat transport capability than single pipe type heat pipes, so development aimed at mounting on electronic devices is underway.

  The loop heat pipe temporarily stores an evaporating unit that evaporates the working fluid (liquid phase working fluid), a condensing unit that condenses the vapor (gas phase working fluid), and the working fluid supplied to the evaporating unit. A compensation chamber. The evaporator and the condenser are connected by a vapor pipe, and the condenser and the compensation chamber are connected by a liquid pipe. Further, inside the evaporation section, there are provided a working fluid passage communicating with the compensation chamber, a steam passage communicating with the steam pipe, and a porous member called a wick that separates the working fluid passage and the steam passage. It has been. The wick has a function of transporting the working fluid in the working fluid channel to the steam channel side by capillary force, and a function for preventing the steam in the steam channel from flowing back to the working fluid channel. A working fluid (including a working fluid and its vapor).

  By the way, electronic devices such as computers are arranged in various directions depending on installation, transportation, storage, and the like. Therefore, it is assumed that the loop heat pipe mounted on the electronic device has a so-called top heat arrangement in which the evaporation portion (high temperature portion) is located above the condensation portion (low temperature portion). In this case, when the operation is stopped, the working fluid flows out of the compensation chamber due to gravity, and the function of transporting the working fluid to the steam channel side and the function of preventing the vapor from flowing backward to the working fluid channel side do not work. It will not be possible to start.

  In order to prevent the occurrence of the above-described problems, in the conventional loop heat pipe, the amount of the working fluid sealed in the loop heat pipe is increased more than the amount capable of obtaining the optimum heat transport characteristic. When the amount of the hydraulic fluid is increased in this way, it becomes possible to fill the inside of the fluid flow path with the hydraulic fluid and moisten the wick even in the top heat arrangement, and the startability of the loop heat pipe is improved.

JP 2009-168273 A JP 2009-115396 A Japanese Patent Laid-Open No. 2002-340489

  However, when the amount of the working fluid sealed in the loop heat pipe is increased as in the prior art, the flow resistance increases with an increase in the ratio of the liquid phase, and the circulating amount of the working fluid decreases. Furthermore, since the ratio of the working fluid is increased in the condensing part, the steam cannot be condensed efficiently. For this reason, the heat transport capability of the loop heat pipe is reduced.

  Then, it aims at providing the loop type heat pipe excellent in startability and heat transport capability, and an electronic device provided with the same.

  According to one aspect, an evaporation unit that receives heat from the outside and evaporates the working fluid, a condensing unit that radiates heat to the outside and condenses the vapor of the working fluid, and a compensation chamber that stores the working fluid flowing into the evaporation unit A steam pipe that guides the vapor of the working fluid generated in the evaporation section to the condensing section, a liquid pipe that guides the working fluid condensed in the condensing section to the compensation chamber, and is disposed in the evaporation section. A wick that separates the hydraulic fluid passage that communicates with the compensation chamber and the vapor passage that communicates with the steam pipe, and is movable between the compensation chamber and the hydraulic fluid passage, There is provided a loop type heat pipe having a spacer that moves into the hydraulic fluid channel when the top heat arrangement is higher than the position of the condensing unit and reduces the volume of the hydraulic fluid channel. .

  According to the loop heat pipe of the above aspect, when the top heat arrangement is adopted, the spacer enters the hydraulic fluid flow path and reduces the volume of the hydraulic fluid flow path. Therefore, even if the hydraulic fluid flows out from the compensation chamber and the hydraulic fluid channel in the top heat arrangement, the hydraulic fluid channel can be filled with the hydraulic fluid remaining in the hydraulic fluid channel. Thereby, the part which a wick contacts with a hydraulic fluid increases, the whole wick can be moistened, and a loop type heat pipe can be started. Furthermore, since it is not necessary to excessively increase the amount of hydraulic fluid sealed in the loop heat pipe, the heat transport characteristics are also excellent.

Fig.1 (a) is a figure which shows the state which stopped the loop type heat pipe which concerns on embodiment in top heat arrangement | positioning, FIG.1 (b) is a compensation chamber and evaporation part in the state of Fig.1 (a) FIG. FIG. 2A is a cross-sectional view showing the evaporator according to the embodiment cut along a plane perpendicular to the wick axis, and FIG. 2B shows the evaporator and the compensation chamber according to the embodiment. FIG. FIG. 3 (a) is a schematic diagram showing the flow of the working fluid in the gas phase when the wick holes are filled with the working fluid, and FIG. 3 (b) is the diagram showing that the wick holes are filled with the working fluid. It is a schematic diagram which shows the flow of the working fluid of the gaseous phase when not being carried out. FIG. 4 is a schematic diagram illustrating a compensation chamber and an evaporation unit according to a reference example. Fig.5 (a) is a figure shown in the state which act | operated the loop type heat pipe which concerns on embodiment by top heat arrangement | positioning, FIG.5 (b) is a cross section which shows the compensation chamber and evaporation part of Fig.5 (a). FIG. Fig.6 (a) is a figure which shows the state which operated the loop type heat pipe which concerns on embodiment by bottom heat arrangement | positioning, FIG.6 (b) shows the compensation chamber and evaporation part in Fig.6 (a) state. It is sectional drawing. 7A to 7C are diagrams illustrating a loop heat pipe according to the embodiment. FIG. 8 is a perspective view showing a computer on which the loop heat pipe according to the embodiment is mounted. FIG. 9 is a side view showing a connection structure between the evaporation part of the loop heat pipe and the electronic component according to the embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

  Fig.1 (a) is a figure shown in the state which stopped the loop type heat pipe which concerns on embodiment by top heat arrangement | positioning, FIG.1 (b) shows the compensation chamber and evaporation part of Fig.1 (a). It is sectional drawing. FIG. 2A is a cross-sectional view showing the evaporator according to the embodiment cut along a plane perpendicular to the wick axis, and FIG. 2B shows the evaporator and the compensation chamber according to the embodiment. FIG. In FIG. 1, an arrow A indicates a vertically upward direction, and the same applies to other drawings.

  As shown in FIG. 1A, the loop heat pipe 10 of the present embodiment includes a compensation chamber 11, an evaporation unit 12, a vapor pipe 13, a condenser pipe (condensing part) 14, and a liquid pipe 15, and inside. The working fluid 18 is enclosed together with steam having a saturated vapor pressure.

  The compensation chamber 11 is disposed adjacent to the evaporation unit 12 and temporarily stores the working fluid 18 to be supplied to the evaporation unit 12. The compensation chamber 11 is located above the evaporation unit 12 when the loop heat pipe 10 is in the top heat arrangement, and is in the bottom heat arrangement (position where the evaporation unit 12 is lower than the position of the condensation unit 14). It is located below the evaporator 12. Inside the compensation chamber 11, for example, a space having an inner diameter of about 14 mm and a length of about 11 mm is provided.

  As shown in FIGS. 1B, 2 </ b> A, and 2 </ b> B, the evaporation unit 12 includes a heat block 21 and a wick 22.

  The heat block 21 is made of a material having good thermal conductivity such as copper, and is formed in a flat plate shape having a length of about 50 mm, a width of about 50 mm, and a thickness of about 20 mm, for example. A cylindrical hollow portion 21a having a diameter of about 14 mm and a length of about 43 mm is formed inside the heat block 21, for example. The wick 22 is accommodated in the cavity portion 21a so as to be in contact with the inner wall of the cavity portion 21a.

  The wick 22 is made of a porous material formed in a cylindrical shape (bottomed cylindrical shape) sealed at one end, and the inner space serves as a hydraulic fluid flow path 22b. The wick 22 has an outer diameter of, for example, about 14 mm and an axial length of about 40 mm, and the hydraulic fluid channel 22b has an inner diameter of, for example, about 5 mm and an axial length of about 33 mm. The porosity of the wick 22 is about 0.5, for example.

  On the outer peripheral side of the wick 22, for example, the width (the length in the circumferential direction of the wick 22) is about 1 mm, the depth (the length in the radial direction of the wick 22) is about 2.5 mm, and the length (the axis of the wick 22). A groove groove (steam channel) 22a having a length in the direction of about 40 mm is formed. For example, about eight steam flow paths 22 a are arranged on the outer periphery of the wick 22 at regular intervals.

  The hydraulic fluid passage 22 b communicates with the compensation chamber 11, and the vapor passage 22 a communicates with the steam pipe 13. Further, the vapor channel 22 a and the hydraulic fluid channel 22 b are separated by the wick 22.

  In the above example, the steam channel 22a is provided on the wick 22 side, but the present embodiment is not limited to this, and the steam channel 22a is provided on the inner peripheral surface side of the cavity 21a of the heat block 21. May be.

  As shown in FIG. 1B, a cylindrical spacer 16 is inserted into the hydraulic fluid channel 22b. The spacer 16 can move between the hydraulic fluid channel 22 b and the compensation chamber 11 due to the height difference between the hydraulic fluid channel 21 b and the compensation chamber 11. That is, when the loop heat pipe 10 is in the top heat arrangement, the spacer 16 moves into the hydraulic fluid passage 22b by its own weight, and reduces the volume in the hydraulic fluid passage 22b. Further, as will be described later, when the loop heat pipe 10 is in the bottom heat arrangement, the spacer 16 moves into the compensation chamber 11 by its own weight and expands the flow path in the working liquid flow path 22b.

  The spacer 16 is made of, for example, a cylindrical aluminum rod having a diameter of about 4.5 mm and a length of about 9 mm. The material of the spacer 16 is not limited to aluminum, and a material having a specific gravity greater than that of the working fluid 18 and hardly causing a chemical reaction with the working fluid, for example, a material such as metal, ceramic, and filler-filled resin is used. it can. The shape of the spacer 16 is not limited to a cylindrical shape, and may be a prismatic shape, a spherical shape, or the like. Further, the surface of the spacer 16 may be covered with a resin material or the like. In this case, it is preferable to cover the spacer 16 with a material (for example, polyfluorinated ethylene) having an affinity for the working fluid 18 so that the working fluid 18 can be smoothly introduced into the working channel 22b. Further, it is preferable that the spacer 16 be chamfered (a process of rounding corners) because the spacer 16 can be moved smoothly.

  As shown in FIG. 1A, the steam pipe 13 connects the evaporator 12 and the condenser pipe 14, and guides the steam generated in the evaporator 12 to the condenser pipe 14. The condenser tube 14 includes a heat sink (not shown), and heat is radiated by the heat sink to condense the vapor and generate the working liquid 18. The liquid pipe 15 connects the condenser pipe 14 and the compensation chamber 11, and guides the hydraulic fluid 18 generated by the condenser pipe 14 to the compensation chamber 11. For example, the steam pipe 13 has an inner diameter of about 3 mm and a length of about 305 mm. The capacitor tube 14 has, for example, an inner diameter of about 3 mm and a length of about 347 mm. Furthermore, the liquid tube 15 has an inner diameter of about 3 mm and a length of about 380 mm, for example. The steam pipe 13, the condenser pipe 14 and the liquid pipe 15 are formed from a metal pipe such as copper.

  As the hydraulic fluid 18 sealed in the loop heat pipe 10, water, a fluorine-based solvent such as fluorinate, alcohols such as ethanol, or the like can be used. Here, for example, about 10 ml (milliliter) of water is sealed in the loop heat pipe 10 as the working fluid 18.

  Next, starting when the loop heat pipe 10 of the present embodiment is in the top heat arrangement will be described. FIG. 3A is a schematic diagram showing the flow of steam when the holes 22e of the wick 22 are filled with the hydraulic fluid 18, and FIG. It is a schematic diagram which shows the flow of the vapor | steam when not satisfy | filled with.

  As shown in FIG. 1A, when the operation of the loop heat pipe 10 is stopped in the top heat arrangement, the working fluid 18 collects on the condensation tube 14 side due to the action of gravity. However, even in this case, the hydraulic fluid 18 remains slightly in the hydraulic fluid passage 22b. These hydraulic fluids 18 are mainly a collection of hydraulic fluids or the like that have penetrated into the holes 22e of the wick 22. In the present embodiment, as shown in FIG. 1B, the spacer 16 enters the hydraulic fluid channel 22b in the top heat arrangement, and the volume in the hydraulic fluid channel 22b is reduced. Therefore, the liquid level of the working fluid 18 remaining in the working fluid flow path 22b rises. At this time, the area of the portion where the wick 22 contacts the hydraulic fluid 18 on the hydraulic fluid flow path 22b side is sufficiently larger than the area of the wick 22 on the vapor flow channel 22a side. Thereby, almost the entire wick 22 can be in a state of being wetted with the hydraulic fluid 18.

  Next, when the evaporation unit 12 is heated, the wick 22 is heated from the outer peripheral side via the heat block 21, and steam is generated on the outer peripheral side of the wick 22 and collected in the steam flow path 22a. At this time, when the entire wick 22 is wet as shown in FIG. 3A, the working fluid 18 is held in the air holes 22 e of the wick 22 by surface tension, and the generated vapor passes through the wick 22. Can not. Therefore, the pressure of the steam rises on the steam flow path 22a side, and the working fluid 18 collected in the steam pipe 13, the condenser pipe 14 and the liquid pipe 15 is pushed out to the compensation chamber 11 side. Thereafter, the working fluid 18 is supplied from the compensation chamber 11 to the working fluid flow path 22b, and the steady working fluid circulation starts, so that the loop heat pipe 10 can be started.

  On the other hand, as shown in FIG. 4, in the case of the reference example in which the spacer 16 is not introduced into the hydraulic fluid passage 22b, the hydraulic fluid passage 22b is obtained when the loop heat pipe is stopped in the top heat arrangement. Only a portion of the lower side is filled with hydraulic fluid 18. For this reason, a part of the upper end side of the wick 22 is not sufficiently wetted. In this case, as shown in FIG. 3B, the steam generated on the steam flow path 22a side of the wick 22 permeates the air holes 22e of the wick 22 and flows back to the working liquid flow path 22b side. For this reason, the pressure difference required for circulating the working fluid between the steam channel 22a and the working fluid channel 22b cannot be generated, and the loop heat pipe cannot be started.

  Next, the operation after the start of starting of the loop heat pipe 10 will be described. FIG. 5A is a diagram showing the loop heat pipe according to the embodiment operated in the top heat arrangement, and FIG. 5B is a cross-sectional view showing the compensation chamber and the evaporation unit in operation. It is.

  As shown in FIG. 5A, in the loop heat pipe 10, the working fluid 18 flows into the compensation chamber 11 through the liquid pipe 15. As shown in FIG. 5B, after the working fluid 18 is temporarily stored in the compensation chamber 11, it moves to the working fluid flow path 22b. The hydraulic fluid 18 in the hydraulic fluid flow path 22 b is carried to the outer peripheral side of the wick 22 by the capillary force of the wick 22, and is evaporated at the outer peripheral portion by heating from the heat block 21. The steam generated at this time flows out of the evaporation section 12 through the steam flow path 22 a and is guided to the condenser pipe 14 by the steam pipe 13. In the condenser tube 14, heat is dissipated to condense the vapor and produce a working fluid 18. The working fluid 18 generated in the condenser pipe 14 is pushed up in the liquid pipe 15 by the pressure difference between the vapor passage 22 a and the working fluid passage 22 b and moves into the compensation chamber 11.

  As described above, the loop heat pipe 10 circulates the working fluid while repeating evaporation and condensation, thereby transporting the heat of the evaporation unit 12 to the heat dissipation unit 14.

  Fig.6 (a) is a figure which shows the state which operated the loop type heat pipe which concerns on embodiment by bottom heat arrangement | positioning, FIG.6 (b) shows the compensation chamber and evaporation part in Fig.6 (a) state. It is sectional drawing.

  As shown in FIGS. 6A and 6B, in the loop heat pipe 10 of this embodiment, when the bottom heat arrangement is adopted, the compensation chamber 11 is arranged below the evaporation section 12, and the inside of the working fluid flow path 22b. The spacer 16 moves into the compensation chamber 11 by its own weight. Thereby, the flow path (cross section) in the hydraulic fluid flow path 22b can be increased, the flow resistance of the hydraulic fluid 18 can be reduced, and the heat transport characteristics can be improved.

  The operation of the loop heat pipe 10 in the bottom heat arrangement is the same as the operation in the top heat arrangement described above.

  Hereinafter, the results of evaluating the startability and heat transport characteristics by producing the loop heat pipe 10 according to the example in which the spacer 16 is introduced and the loop heat pipe according to the comparative example in which the spacer 16 is not introduced will be described.

  7A to 7C are diagrams illustrating a loop heat pipe according to the embodiment.

  As shown in FIGS. 7A to 7C, the steam pipe 13 of the loop heat pipe 10 of the embodiment has an inner diameter of 3 mm × length of 305 mm, the condenser pipe 14 has an inner diameter of 3 mm × length of 347 mm, and the liquid pipe 15 has an inner diameter of It was 3 mm × length 347 mm. The compensation chamber 11 has an inner diameter φ1 of 14 mm and a length L1 of 11 mm. A wick 22 having a porosity of 0.5 was used. The wick 22 has an outer diameter φ3 of 14 mm and a length L4 of 40 mm. The working fluid flow path 22b has an inner diameter φ2 of 5 mm and a length L2 of 41 mm. Note that the length L3 of the hydraulic fluid passage 22b in the wick 22 is 33 mm. The gap L6 between the end of the wick 22 on the steam pipe 13 side and the end of the cavity 21a on the steam pipe 13 side is about 3 mm. The steam channel 22 a has a width W 1 of 1 mm, a depth D 1 of 2.5 mm, and a length L 5 of 40 mm. Eight steam channels 22 a are formed on the outer periphery of the wick 22 at equal intervals.

  Three columnar spacers 16 having a diameter of 4.5 mm and a length of 9 mm were introduced into the compensation chamber 11 and the steam flow path 22a. The spacer 16 is made of aluminum and the surface thereof is covered with a polyfluoroethylene resin.

  In this example, 10 ml of water (liquid) was sealed as a working fluid in the loop heat pipe described above under reduced pressure (saturated vapor pressure).

  The volume of each part of the loop heat pipe of the example is shown in Table 1 below.

以上のループ型ヒートパイプ１０について、トップヒート配置及びボトムヒート配置での始動性及び熱輸送特性を評価した。なお、トップヒート配置での始動性の試験は、図７（ａ）に示すように、作動液１８が補償チャンバ１１内から流出した状態として行った。また、熱輸送特性は、蒸発部への入熱量Ｑ［Ｗ］に対する蒸発部と凝縮部の温度差ΔＴ［℃］から熱抵抗ΔＴ／Ｑ［℃／Ｗ］を求めて評価した。なお、熱抵抗が小さいほどループ型ヒートパイプの熱輸送特性に優れることを意味する。

About the loop type heat pipe 10 described above, startability and heat transport characteristics in the top heat arrangement and the bottom heat arrangement were evaluated. In addition, the startability test in the top heat arrangement was performed in a state where the working fluid 18 flowed out of the compensation chamber 11 as shown in FIG. The heat transport characteristics were evaluated by obtaining the thermal resistance ΔT / Q [° C./W] from the temperature difference ΔT [° C.] between the evaporation portion and the condensation portion with respect to the heat input Q [W] to the evaporation portion. In addition, it means that it is excellent in the heat transport characteristic of a loop type heat pipe, so that heat resistance is small.

  As a result, it was confirmed that the loop heat pipe 10 of the example can be started in either case of the top heat arrangement or the bottom heat arrangement. Moreover, the heat resistance in the top heat arrangement of the loop heat pipe 10 was 0.62 ° C./W, and the heat resistance in the bottom heat arrangement was 0.35 ° C./W.

  Next, a loop heat pipe according to Comparative Example 1 will be described.

  The loop type heat pipe according to the comparative example 1 is substantially the same as the loop type heat pipe 10 of the embodiment shown in FIGS. 7A to 7C, but spacers are provided in the compensation chamber 11 and the hydraulic fluid flow path 22b. 16 is not introduced. In the first comparative example, the length L2 of the compensation chamber 11 is set to 21 mm so that the heat transport property is prioritized, and the capacity is about twice that of the compensation chamber 11 of the embodiment. Further, the amount of water to be sealed was 9.2 ml, which was smaller than in the example. Others are the same as the embodiment.

  About the loop type heat pipe of Comparative Example 1, when the startability in the top heat arrangement and the bottom heat arrangement was evaluated under the same conditions as in the example, it was able to start in the case of the bottom heat arrangement, but the top heat arrangement Then I could not start. Moreover, the heat resistance of the loop heat pipe of the comparative example was 0.30 ° C./W in the bottom heat arrangement.

  From the above, Comparative Example 1 has excellent heat transport characteristics in the bottom heat configuration, cannot be started in the top heat configuration, and cannot achieve both heat transport characteristics and startability.

  Next, a loop heat pipe according to Comparative Example 2 will be described.

  The structure and size of the loop heat pipe of Comparative Example 2 are the same as those of Comparative Example 1. However, in Comparative Example 2, in order to improve startability, the amount of water sealed in the loop heat pipe was set to 11.3 ml, and the amount of hydraulic fluid was increased by about 20% compared to Comparative Example 1.

  About the loop type heat pipe of the comparative example 2, the startability in top heat arrangement | positioning and bottom heat arrangement | positioning was evaluated on the conditions similar to an Example. As a result, it was confirmed that the loop heat pipe could be started in both the bottom heat arrangement and the top heat arrangement. Moreover, the thermal resistance of the loop heat pipe of Comparative Example 2 was 2.46 ° C./W in the top heat configuration and 2.21 ° C./W in the bottom heat configuration.

  As described above, although the startability in the top heat arrangement can be improved in the loop heat pipe of Comparative Example 2, the heat transport characteristics are greatly deteriorated, and the heat transport characteristics and the startability cannot be compatible.

  As described above, according to the loop heat pipe 10 of the present embodiment, the spacer 16 enters the hydraulic fluid passage 22b when the top heat arrangement is achieved, and the volume of the hydraulic fluid passage 22b is reduced. Therefore, the hydraulic fluid passage 22b can be filled with a small amount of the hydraulic fluid 18 remaining in the hydraulic fluid passage 22b in the top heat arrangement. Thereby, since the part in which the wick 22 contacts the hydraulic fluid 18 increases, almost the whole wick 22 can be moistened, and startability from the top heat arrangement can be improved. Furthermore, since it is not necessary to excessively increase the amount of the working fluid 18 sealed in the loop heat pipe 10, the heat transport characteristics are excellent.

  Hereinafter, an example in which the loop heat pipe according to the present embodiment is mounted on an electronic device will be described. FIG. 8 is a perspective view showing a computer on which the loop heat pipe according to the embodiment is mounted. FIG. 9 is a side view showing a connection structure between the evaporation section and the heat generating component of the loop heat pipe according to the embodiment.

  As shown in FIG. 8, an electronic device (computer) 80 includes an electronic component 85 having a large heat generation amount such as a CPU, a wiring board 81 on which the electronic component 85 is mounted, a cooling fan 82 for taking in outside air, and an auxiliary device. A hard disk drive 83 as a storage device and a power supply unit 84 are provided. The loop heat pipe 10 is mounted on the wiring board 81, and the capacitor tube 14 (and the heat sink) is disposed in the vicinity of the cooling fan 82. Further, the evaporation section 12 of the loop heat pipe 10 is joined to the upper surface of the electronic component 85 via thermal grease 86 as shown in FIG.

  As described above, since the electronic device 80 of the present embodiment has the loop heat pipe 10 mounted thereon, for example, the Y1 direction is vertically upward in FIG. It can be carried out. Furthermore, since the loop heat pipe 10 of this embodiment has a high heat transport capability, it is possible to efficiently dissipate heat, and the air volume of the cooling fan 82 is suppressed to reduce the noise of the electronic device 80 and to drive the cooling fan 82. Electric power can be suppressed.

  The following additional notes are further disclosed with respect to the embodiment including the above examples.

(Supplementary note 1) an evaporation unit that receives heat from outside and evaporates the working fluid;
A condensing part for radiating heat to the outside and condensing the vapor of the hydraulic fluid;
A compensation chamber for storing hydraulic fluid flowing into the evaporator;
A steam pipe for guiding the vapor of the hydraulic fluid generated in the evaporation section to the condensation section;
A liquid pipe for guiding the hydraulic fluid condensed in the condensing unit to the compensation chamber;
A wick that is disposed in the evaporation section and separates a working fluid passage that communicates with the compensation chamber and a steam passage that communicates with the steam pipe;
It is movable between the compensation chamber and the hydraulic fluid flow path, and moves to the hydraulic fluid flow path when the position of the evaporator is higher than the position of the condenser. A spacer for reducing the volume of the hydraulic fluid flow path;
A loop-type heat pipe characterized by comprising:

  (Supplementary note 2) The loop heat pipe according to supplementary note 1, wherein the spacer moves into the compensation chamber when the position of the evaporating part is lower than the position of the condensing part.

  (Appendix 3) The compensation chamber and the hydraulic fluid flow path have a difference in height when the top heat arrangement or the bottom heat arrangement is established, and the spacer is caused by its own weight between the compensation chamber and the hydraulic fluid flow path. The loop-type heat pipe according to appendix 1 or 2, wherein the loop type heat pipe moves between the loops.

  (Supplementary note 4) The loop heat pipe according to any one of supplementary notes 1 to 3, wherein a surface of the spacer is covered with a material having affinity for the hydraulic fluid.

  (Supplementary note 5) The loop heat pipe according to supplementary note 3, wherein the spacer is made of a material having a specific gravity greater than that of the hydraulic fluid.

  (Additional remark 6) The loop type heat pipe of Additional remark 3 characterized by the cross section of the said hydraulic fluid flow path being circular, and the said spacer being formed in the column shape.

(Appendix 7) An evaporation unit that receives heat from the outside and evaporates the working fluid;
A condensing part for radiating heat to the outside and condensing the vapor of the hydraulic fluid;
A compensation chamber for storing hydraulic fluid flowing into the evaporator;
A steam pipe for guiding the vapor of the hydraulic fluid generated in the evaporation section to the condensation section;
A liquid pipe for guiding the hydraulic fluid condensed in the condensing unit to the compensation chamber;
A wick that is disposed in the evaporation section and separates a working fluid passage that communicates with the compensation chamber and a steam passage that communicates with the steam pipe;
It is movable between the compensation chamber and the hydraulic fluid flow path, and moves to the hydraulic fluid flow path when the position of the evaporator is higher than the position of the condenser. A spacer for reducing the volume of the hydraulic fluid flow path;
An electronic device equipped with a loop heat pipe having
The electronic device is characterized in that the evaporation section is thermally connected to an electronic component that generates heat.

  (Additional remark 8) The said condensation part is arrange | positioned in the vicinity of the cooling fan, The electronic device of Additional remark 7 characterized by the above-mentioned.

  DESCRIPTION OF SYMBOLS 10 ... Loop type heat pipe, 11 ... Compensation chamber, 12 ... Evaporating part, 13 ... Steam pipe, 14 ... Condenser pipe (condensing part), 15 ... Liquid pipe, 16 ... Spacer, 18 ... Working liquid, 21 ... Heat block, 21a ... Cavity, 22 ... Wick, 22a ... Vapor channel (groove), 22b ... Working fluid channel, 22e ... Gap, 80 ... Computer (electronic device), 81 ... Wiring board, 82 ... Cooling fan, 83 ... Hard disk Drive, 84 ... power supply, 85 ... electronic component, 86 ... thermal grease.

Claims (6)

An evaporating section that receives heat from outside and evaporates the working fluid;
A condensing part for radiating heat to the outside and condensing the vapor of the hydraulic fluid;
A compensation chamber for storing hydraulic fluid flowing into the evaporator;
A steam pipe for guiding the vapor of the hydraulic fluid generated in the evaporation section to the condensation section;
A liquid pipe for guiding the hydraulic fluid condensed in the condensing unit to the compensation chamber;
A wick that is disposed in the evaporation section and separates a working fluid passage that communicates with the compensation chamber and a steam passage that communicates with the steam pipe;
It is movable between the compensation chamber and the hydraulic fluid flow path, and moves to the hydraulic fluid flow path when the position of the evaporator is higher than the position of the condenser. A spacer for reducing the volume of the hydraulic fluid flow path;
A loop-type heat pipe characterized by comprising:   2. The loop heat pipe according to claim 1, wherein the spacer moves into the compensation chamber when the position of the evaporating part is lower than the position of the condensing part.   When the compensation chamber and the hydraulic fluid flow path are in a top heat configuration or a bottom heat configuration, a difference in height is generated, and the spacer moves between the compensation chamber and the hydraulic fluid flow path by its own weight. The loop heat pipe according to claim 1 or 2, characterized by the above.   The loop heat pipe according to any one of claims 1 to 3, wherein a surface of the spacer is covered with a material having affinity for the hydraulic fluid.   The loop heat pipe according to claim 3, wherein the spacer is made of a material having a specific gravity greater than that of the hydraulic fluid. An evaporating section that receives heat from outside and evaporates the working fluid;
A condensing part for radiating heat to the outside and condensing the vapor of the hydraulic fluid;
A compensation chamber for storing hydraulic fluid flowing into the evaporator;
A steam pipe for guiding the vapor of the hydraulic fluid generated in the evaporation section to the condensation section;
A liquid pipe for guiding the hydraulic fluid condensed in the condensing unit to the compensation chamber;
A wick that is disposed in the evaporation section and separates a working fluid passage that communicates with the compensation chamber and a steam passage that communicates with the steam pipe;
It is movable between the compensation chamber and the hydraulic fluid flow path, and moves to the hydraulic fluid flow path when the position of the evaporator is higher than the position of the condenser. A spacer for reducing the volume of the hydraulic fluid flow path;
An electronic device equipped with a loop heat pipe having
The electronic device is characterized in that the evaporation section is thermally connected to an electronic component that generates heat.

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