JP5224328B2 - Fine metal wire, wick structure and heat pipe using the same - Google Patents

Description

  The present invention relates to a fine metal wire, a wick structure, and a heat pipe using the same, and more particularly to a wick structure used for cooling a small electronic device such as a personal computer and a heat pipe using the wick structure.

  Due to the increase in the heat generation amount and heat generation density of CPUs, elements, etc., there is a demand for a high-performance cooling technology with excellent heat dissipation efficiency. Conventionally, heat sinks combined with heat pipes that transport a large amount of heat have been widely used. A space serving as a flow path for the working fluid is provided inside the heat pipe, and heat is moved by the phase change or movement of the working fluid accommodated in the space such as evaporation and condensation. That is, on the heat absorption side of the heat pipe, the working fluid evaporates due to the heat generated by the parts to be cooled that are conducted through the material of the container constituting the heat pipe, and the vapor moves to the heat radiation side of the heat pipe. To do. On the heat radiating side, the working fluid vapor is cooled and returned to the liquid phase again. The working fluid that has returned to the liquid phase in this way moves (refluxs) again to the heat absorption side. Heat is transferred by such phase transformation and movement of the working fluid.

  The heat pipe is provided with a wick structure such as a groove, a mesh, and a sintered metal body for refluxing the working fluid sealed in the container from the condensing unit to the evaporating unit. In general, the wick structure has a dilemma that the smaller the pore radius of the pore portion, the stronger the capillary force, while the higher the channel resistance when steam flows. Conversely, the larger the pore radius, the lower the channel resistance, but the capillary force becomes weaker. There is a need to realize a wick structure with two conflicting elements, strong capillary force and low flow resistance.

JP 2003-148886 A Japanese Patent Laid-Open No. 2003-214779 JP 2007-056302 A

  The wick structure disclosed in Patent Literature 1 is enclosed in a pipe body having a sealed hollow portion, a porous metal body layer disposed so as to be in contact with the inner peripheral surface of the pipe body, and the pipe body. Working fluid. The porous metal body layer has a first porous part partitioned in the circumferential direction and a second porous part having a porosity smaller than that of the first porous part. That is, a high-porosity portion and a low-porosity portion are simultaneously provided on the inner peripheral surface of the heat pipe to achieve a strong capillary force and a low flow resistance (ie, high permeability).

  However, the wick structure disclosed in Patent Document 1 has the following problems. That is, it is difficult to dispose metal particles having different particle diameters only on a part of the inner peripheral surface of a pipe (particularly a bare pipe having no groove). Furthermore, it is difficult to sinter metal particles having different particle sizes. It is necessary to prepare many materials such as metal particles having different particle diameters, resulting in high costs. When the heat pipe is used, the direction in which the heat pipe is arranged is limited, for example, a portion where the capillary force is strong must be arranged downward. When flattening the heat pipe, cracks are likely to occur between metals of different diameters.

  The heat pipe disclosed in Patent Document 2 is a flat plate type heat pipe in which a wick that constitutes a passage for generating a capillary force and flowing a working fluid by the capillary pressure is disposed in a hollow flat plate-like container. As the wick structure, a wick having a small effective capillary radius is arranged on the heat input section side, and a wick having a large cross-sectional area of the flow path through which the working fluid flows is arranged on the heat radiating section side. The two wick channels are in communication with each other. That is, the reflux characteristic of the working fluid from the heat radiating unit to the evaporation unit is excellent.

  However, the technique disclosed in Patent Document 2 has the following problems. That is, it is difficult to arrange metal particles having different particle diameters in the length direction other than the flat heat pipe. Furthermore, it is difficult to sinter metal particles having different particle sizes. The cost increases because the number of materials increases, such as preparing metal particles with different particle sizes. Since the portion having a small particle size must be disposed in the evaporation portion and the portion having a large particle size must be disposed in the condensation portion, the direction of the evaporation portion and the condensation portion is limited when the heat pipe is used. Furthermore, when there are a plurality of heat sources, the internal structure of the heat pipe must be changed according to the arrangement of the heat sources.

  In the method for producing a sintered wick disclosed in Patent Document 3, an unsintered wick layer is formed on the inner wall surface of a metal pipe with a mixture of at least two types of powders having different average particle diameters. Is a method for producing a sintered wick layer of a heat pipe that is heated and sintered in a reducing atmosphere. As a result, a heat pipe having good productivity, high capillary force and excellent working fluid circulation is achieved. That is, by mixing and using two kinds of sintered metals, it is trying to achieve both high capillary force and high transmittance.

  However, according to Patent Document 3, there are the following problems. That is, it is difficult to sinter metal particles having different particle sizes. The cost increases because the number of materials increases, such as preparing metal particles with different particle sizes. Although metal particles of different diameters are mixed, the average porosity is a value determined by the ratio of the two particles (that is, substantially the same as using one kind of metal particles with the desired porosity). Furthermore, it is not possible to separate a portion with a strong capillary force and a portion with a high transmittance.

  As described above, in the prior art, a method using two or more different wick structures has been adopted in order to realize a wick structure having a high capillary force and a low channel resistance. However, the use of two or more types of wick structures has various problems such as complicated manufacturing processes and high material costs.

  Accordingly, an object of the present invention is to provide a wick structure having a high capillary force and a high gas phase hydraulic fluid permeability that can be produced by a simple method, and a heat pipe using the wick structure.

  The inventor has conducted extensive research to solve the above-described conventional problems. As a result, the fine metal wire is oxidized at a predetermined temperature for a predetermined time to form an oxide film on the surface of the fine metal wire, and the thin metal wire having the oxide film formed on the surface is reduced at a predetermined temperature in a reducing gas atmosphere. Then, it was found that a metal surface portion having a fine gap portion was formed integrally on the entire surface of the metal core portion having no fine gap portion, and the fine gap portion had a strong capillary force.

  Further, the metal thin wire formed with the metal surface portion having the fine gap portion is integrated with the entire surface of the metal core portion without the fine gap portion thus formed, and the resistance of the gas-phase hydraulic fluid is small. It was found that a wick structure having a high capillary force and a high gas phase hydraulic fluid permeability can be produced by a simple method when a plurality of wick structures are combined so as to flow. The present invention has been made based on the above-described results.

A first aspect of the fine metal wire for wick used in the heat pipe of the present invention is a fine metal gap and a fine gap having a high capillary force between the metal core and the metal core. And a metal film part forming
The metal thin wire is expanded by oxidizing, and the expanded metal thin wire is reduced and contracted to stand up so that the metal flakes are peeled off from the metal core to form the metal film, and the metal core The metal core portion and the metal film portion are formed by oxidizing and reducing the fine metal wire at a temperature at which the fine gap portion can be formed between the surface of the portion and the metal film portion. It is a thin metal wire for wicks used for a heat pipe characterized by being.

A first aspect of the wick structure according to the present invention is a metal core portion and a metal film portion that is made of the same metal as the metal core portion and forms a fine gap portion having a high capillary force between the metal core portion. The metal thin wire is expanded by oxidizing, and the expanded metal thin wire is reduced and contracted to rise so that the metal flakes are peeled off from the metal core to form the metal film portion. The metal core portion and the metal film portion are reduced by oxidizing the fine metal wire after being oxidized at a temperature at which the fine gap portion can be formed between the surface of the metal core portion and the metal film portion. This is a wick structure formed by combining a plurality of thin metal wires.

A second aspect of the wick structure according to the present invention is a wick structure characterized in that the plurality of fine metal wires are knitted in a net shape.

According to a third aspect of the wick structure of the present invention, the wick structure is characterized in that the plurality of fine metal wires are superposed.

The first aspect of the metal pipe for a container used for the heat pipe of the present invention is a groove wall surface part that forms a groove part formed on an inner wall of the pipe, and the groove wall surface part is made of the same metal as the groove wall surface part. And a groove metal film portion that forms a fine gap portion with high capillary force,
The tube is expanded by oxidizing, and the expanded tube is reduced and contracted to rise so that the metal flakes are peeled off from the groove wall surface portion to form the groove metal film portion, and the groove wall surface portion The groove wall surface portion and the groove metal film portion are formed by oxidizing and reducing the tube at a temperature at which the fine gap portion can be formed between the surface and the groove metal film portion. It is the metal pipe for containers used for the heat pipe characterized by this.

A second aspect of the container for metal tubes for use in heat pipe of the present invention, a container for a metal tube for use in heat pipes, wherein the groove metal film portion and the groove wall surface portion is formed on at least part of the inner wall is there.

According to a first aspect of the heat pipe of the present invention, a groove wall surface portion forming a groove portion formed on an inner wall of a tube is made of the same metal as the groove wall surface portion, and a capillary force is generated between the groove wall surface portion. A groove metal film portion that forms a high fine gap , and the tube is expanded by oxidizing, and the expanded tube is reduced and contracted, so that the metal flakes are peeled off from the groove wall surface portion. Forming the groove metal film portion and oxidizing and reducing the tube at a temperature capable of forming the fine gap portion between the surface of the groove wall surface portion and the groove metal film portion. It is a heat pipe provided with the container which consists of a metal pipe in which the wall surface part and the groove metal film part are formed , and the working fluid enclosed in the container.

The second aspect of the heat pipe of the present invention includes a sealed container, a metal core portion disposed in the container, and the metal core portion made of the same metal, between the metal core portion, A metal film portion that forms a fine gap portion having a high capillary force, expands by oxidizing the fine metal wire, and reduces and contracts the expanded metal fine wire, thereby reducing the metal flake from the metal core portion. The metal thin film is formed so as to be peeled off to form the metal film, and the metal fine wire is oxidized and reduced at a temperature at which the fine gap can be formed between the surface of the metal core and the metal film. Thus, the heat pipe includes a wick structure formed by combining a plurality of fine metal wires in which the metal core part and the metal film part are formed , and a working fluid sealed in the container.

According to a third aspect of the heat pipe of the present invention, a groove wall surface portion forming a groove portion formed on an inner wall of the tube and the groove wall surface portion are made of the same metal, and a capillary force is generated between the groove wall surface portion. A groove metal film portion that forms a high fine gap , and the tube is expanded by oxidizing, and the expanded tube is reduced and contracted, so that the metal flakes are peeled off from the groove wall surface portion. Forming the groove metal film portion and oxidizing and reducing the tube at a temperature capable of forming the fine gap portion between the surface of the groove wall surface portion and the groove metal film portion. A container made of a metal tube in which a wall surface part and a groove metal film part are formed ;
A metal core placed on the groove metal film part of the metal tube, and a metal made of the same metal as the metal core part and forming a fine gap portion having a high capillary force between the metal core part And a metal part is expanded by oxidizing the metal thin line, and the expanded metal thin line is reduced and contracted to stand up so that the metal flakes are peeled off from the metal core part, and the metal film part is The metal core portion and the metal film are formed and reduced after oxidizing the fine metal wires at a temperature at which the fine gap portion can be formed between the surface of the metal core portion and the metal film portion. And a wick structure formed by combining a plurality of fine metal wires formed with parts ,
It is a heat pipe provided with the working fluid enclosed in the container.

In the first aspect of the method for producing a fine metal wire for wick used in the heat pipe of the present invention, the fine metal wire is expanded by oxidizing, and the expanded fine metal wire is reduced and contracted, thereby reducing the metal core portion. A metal film portion is formed by standing up so that the metal flakes are peeled off, and the metal fine wire is oxidized and then reduced at a temperature at which a fine gap portion can be formed between the surface of the metal core portion and the metal film portion. By this, in the manufacturing method of the thin metal wire for wicks used for the heat pipe which forms the metal film part which forms the fine gap part with high capillary force between the metal core part and the metal core part. is there.
In the first aspect of the manufacturing method of the wick structure according to the present invention, a plurality of fine metal wires are knitted into a mesh to form a mesh,
The metal thin wire is expanded by oxidizing, and the expanded metal thin wire is reduced and contracted to rise so that the metal flakes are peeled off from the metal core to form a metal film portion. At a temperature at which a fine gap can be formed between the surface and the metal film part, the mesh is oxidized to form an oxide film on the surface of the metal fine wire,
The mesh having an oxide film formed on the surface is reduced at a predetermined temperature under a reducing gas atmosphere, and the capillary core force is high between the metal core portion of the metal thin wire and the metal core portion. This is a method for manufacturing a wick structure, in which the metal film part for forming the fine gap part is formed.

In the first aspect of the method for producing a metal pipe for a container used for the heat pipe of the present invention, a groove is formed along the longitudinal direction on the inner wall of the pipe,
The tube is expanded by oxidizing, and the expanded tube is reduced and contracted to rise so that the metal flakes are peeled off from the groove wall surface portion to form a groove metal film portion, and the surface of the groove wall surface portion Oxidizing the inner wall of the tube provided with the groove at a temperature capable of forming a fine gap with the groove metal film, and forming an oxide film on the surface of the groove wall surface forming the groove;
The groove metal that reduces the groove wall surface portion having an oxide film formed on the surface thereof at a predetermined temperature in a reducing gas atmosphere to form the fine gap portion having a high capillary force between the groove wall surface portion and the groove wall surface portion. It is a manufacturing method of the metal pipe for containers used for a heat pipe which manufactures a metal pipe provided with a membrane part.

In the first aspect of the heat pipe manufacturing method of the present invention, a groove is formed along the longitudinal direction on the inner wall of the pipe,
The tube is expanded by oxidizing, and the expanded tube is reduced and contracted to rise so that the metal flakes are peeled off from the groove wall surface portion to form the groove metal film portion, and the groove wall surface portion in the fine gap portions capable of forming a temperature between the surface and the groove metal film unit, by oxidizing the inner wall of the tube with the groove, the oxide film on the surface of the groove wall surface portion forming the groove Forming,
At a predetermined temperature in a reducing gas atmosphere, by reducing the groove wall portion where the oxide film is formed on the surface, between the groove wall surface portion, the groove the metal forming the high capillary force the fine gap Prepare a metal tube with a membrane part,
The metal thin wire is expanded by oxidizing, and the expanded metal thin wire is reduced and contracted to rise so that the metal flakes are peeled off from the metal core to form a metal film portion. in formable temperature fine gap between the surface and the metal film unit, by oxidizing a thin line of the metal oxide film is formed on the surface of the thin line of the metal,
At a predetermined temperature in a reducing gas atmosphere, by reducing fine lines of the metal oxide film formed on its surface, and the metal core, between said metal core, high capillary force the fine gap a plurality of thin metal wires and a said metal film portion that forms were prepared,
The wick structure is prepared by knitting the plurality of fine metal wires into a net shape,
It is a manufacturing method of a heat pipe which mounts the wick structure on the surface of the groove surface part, and manufactures a heat pipe .

The outer periphery of the mesh peeling part (ie, the metal film part) has a large pore radius and functions as a wick structure having a high permeability like the mesh without the conventional peeling part. The flow resistance generated at the time is small, and the working fluid moves smoothly. On the other hand, since the pore radius is small between the core part and the peeling part of the mesh wire and it functions as a wick structure with a high capillary force, the pump pressure from the condensing part to the evaporating part is strengthened, and the working fluid is returned Is promoted. Due to the two actions described above, a wick structure having a high capillary force and a high transmittance can be obtained.
Further, since one type of wick structure is used, processing is easy and cost reduction can be achieved. Furthermore, since the heat pipe operates smoothly regardless of the direction, there is no need to change the internal configuration for each heat pipe arrangement direction.

A wick structure of the present invention and a heat pipe using the same will be described with reference to the drawings.
One aspect of the thin metal wire of the present invention is a thin metal wire used in a wick structure, and a metal film that forms a fine gap portion having a high capillary force between the metal core portion and the metal core portion. It is a metal fine wire provided with a part.

  FIG. 1 is a cross-sectional view illustrating one embodiment of a fine metal wire according to the present invention. The metal thin wire is, for example, a copper thin wire. As shown in FIG. 1, a fine metal wire 1 according to one aspect of the present invention includes a metal core portion 2 located in the center and a metal film portion 3 that forms a fine gap portion 4 between the metal core portion 2 and It has. The metal film part 3 is formed so as to cover the periphery of the metal core part 2 in a skin shape. The metal core part and the metal film part may be formed integrally or may be formed separately. The diameter of the metal thin wire is usually φ0.08 mm, and may be within a range of approximately φ0.05 mm to 0.25 mm.

  The cross-sectional shape in which the metal core part 2, the fine gap part 4, and the metal film part 3 shown in FIG. However, although the cross-sectional shape itself including the metal core part 2, the fine gap part 4, and the metal film part 3 is not the same shape, the size, shape, and position of the metal film part 3 and the fine gap part 4 change, A cross-sectional shape as shown in FIG. 1 is present along substantially the entire circumference of the outer surface of the metal core portion 2 along the longitudinal direction of the fine metal wire 1. The fine gap portion 4 formed between the metal core portion and the metal film portion is excellent in capillary force, and the fine gap portion 4 having high capillary force exists along the longitudinal direction of the fine metal wire 1.

  The fine metal wire of the present invention can be produced by the following method. That is, the fine metal wire is oxidized at a predetermined temperature for a predetermined time to form an oxide film on the surface of the fine metal wire, and the fine metal wire having the oxide film formed on the surface is reduced at a predetermined temperature in a reducing gas atmosphere. Thus, a fine metal wire having a metal core part and a metal film part forming a fine gap part having a high capillary force between the metal core part is manufactured.

  One of the methods for producing a fine metal wire of the present invention is a method using oxidation / reduction by heating. For example, first, the fine metal wires are oxidized at a high temperature (650 ° C., about 30 minutes). Subsequently, it reduces in a reducing gas atmosphere (550 degreeC, about 10 minutes). The reducing gas is a gas for reducing oxidized metal, such as copper, and is an argon gas and a hydrogen gas and has a hydrogen content of about 5%. When a fine metal wire is oxidized at a high temperature, the fine metal wire expands and becomes thicker than the original wire diameter. Next, when the reduction is performed under a reducing gas atmosphere (550 ° C., about 10 minutes), the expanded portion remains and the fine metal wire contracts. The contracted portion becomes the metal core portion of the thin metal wire, and becomes a metal film portion showing a shape such that the portion remaining after the expansion is peeled off. The narrow gaps formed between the metal core portion of the thin metal wire formed in this way and the metal film portion shaped as peeled off provide a strong capillary force.

  As another method for producing a fine metal wire according to the present invention, there is oxidation using a chemical. For example, yellow or red cuprous oxide is produced by using a treatment liquid of a copper acetate / copper sulfate / barium sulfide / ammonium chloride system. Alternatively, black cupric oxide is produced by using a sodium chlorite / sodium hydroxide treatment solution. Subsequently, it reduces in a reducing gas atmosphere (550 degreeC, about 10 minutes).

  As described above, the fine flow path for the liquid-phase working fluid is formed by the fine gap portion formed between the metal core portion and the metal film portion. Therefore, the metal fine wire of the present invention itself has a fine gap portion having a high capillary force on the outer surface portion, and can be applied in various fields where a high capillary force is required.

  One aspect of the wick structure of the present invention is a combination of a plurality of fine metal wires each having a metal core portion and a metal film portion forming a fine gap portion having a high capillary force between the metal core portion. It is a formed wick structure. That is, it is formed by combining a plurality of the above-described fine metal wires, for example, knitted in a net shape.

  FIG. 2 is a partial plan view for explaining a wick structure formed by combining a plurality of fine metal wires and knitting in a net shape. As shown in FIG. 2, a plurality of fine metal wires are alternately combined and knitted in a lattice shape. As shown in the figure, fine irregularities exist on the surface of the fine metal wire, but each fine metal wire has a fine gap portion with high capillary force between the metal core portion and the metal core portion. The metal core portion and the metal film portion are made of the same metal, and the fine gap portion is raised between the metal core portion and the surface of the metal core portion. Is formed. In the figure, a single mesh formed by alternately knitting a plurality of fine metal wires in a grid pattern is shown, but a plurality of meshes of fine metal wires knitted in a grid pattern may be superimposed and arranged.

  The wick structure is manufactured in the same manner as described above. That is, a mesh formed by meshing a plurality of fine metal wires is formed, and the fine metal wires forming the mesh knitted in a mesh shape are oxidized at a predetermined temperature for a predetermined time (for example, 650 ° C. for about 30 minutes). An oxide film is formed on the surface of the metal, and the metal thin wire having the oxide film formed on the surface is reduced at a predetermined temperature in a reducing gas atmosphere at a predetermined temperature (for example, about 550 ° C. for about 10 minutes). And a wick structure consisting of a plurality of fine metal wires provided with a metal film part that forms a fine gap part having a high capillary force between the metal core part.

  FIG. 3 is a partial cross-sectional view illustrating one embodiment of the wick structure. FIG. 4 is a schematic cross-sectional view illustrating the details. In the drawing, a linear portion extending in the horizontal direction is a vertical cross section of one thin metal wire 1, and a circular portion located in the vicinity thereof is a cross section of another thin metal wire 1. As shown in FIGS. 3 and 4, a thin metal film portion 3 is formed along the outer surface of the metal core portion 2 of the vertically long thin metal wire 1 in the longitudinal section of the thin metal wire 1. A fine gap portion 4 is formed between the metal film portion 3 and the metal core portion 2.

  As is clear from this figure, there are fine gaps on the outer surface along the longitudinal direction of the fine metal wires forming the wick structure. The fine gaps described above are formed over the entire length of the vertically long fine metal wires shown in the longitudinal section. A single fine gap is not necessarily formed over the entire length, but a plurality of fine gaps are formed so as to communicate with each other. As a result, a portion having a strong capillary force is formed over the entire length on the surface of the metal fine wire. ing. As described above, another fine metal wire shown in a cross section is arranged in the vicinity of a vertically long metal wire shown in a vertical cross section.

  As clearly shown by another thin metal wire shown in a cross section shown in FIGS. 3 and 4, a metal film portion is formed on the outer surface of the central metal core portion. A fine gap is formed between the thin metal piece formed so as to be peeled off from the metal core and the surface of the metal core. As is apparent from the figure, the fine gap portion differs in shape, size, and position, but it can be seen that a fine gap portion having a strong capillary force is formed around the metal core portion.

  In the wick structure shown in FIGS. 2 to 4, a fine gap portion having a strong capillary force is formed over the entire outer surface of the metal core portion of each fine metal wire forming the wick structure. By appropriately arranging the individual thin metal wires formed in (1), a flow path with a small flow path resistance through which the evaporated working fluid flows is formed. Accordingly, a wick structure having a high capillary force and a high permeability of the gas-phase working fluid can be obtained.

  One aspect of the heat pipe of the present invention includes a sealed container, a metal core portion disposed in the container, and a metal film portion that forms a fine gap portion having a high capillary force between the metal core portion. A heat pipe provided with a wick structure formed by combining a plurality of fine metal wires provided with a working fluid sealed in a container.

  FIG. 5 is a schematic diagram for explaining one embodiment of the heat pipe of the present invention. Fig.5 (a) is a cross-sectional view explaining a heat pipe. FIG.5 (b) is an enlarged view of the part shown with the dotted line of Fig.5 (a).

  As shown in FIG. 5A, the heat pipe 10 includes a sealed container 11, a metal core part disposed in the container 11, and a fine gap part having a high capillary force between the metal core part. And a wick structure 12 formed by combining a plurality of fine metal wires provided with a metal film portion that forms a container, and a working fluid such as water is sealed in the container. There is a heat absorption part to which the heating element is thermally connected on one flat surface of the container, and a heat radiation part to which the radiation fin is thermally connected to the other part of the container.

  As shown in FIG. 5B, the wick structure 12 is installed on the inner wall of the container 11. The wick structure 12 is formed in a mesh shape in which the fine metal wires 1 are arranged in a lattice shape and are combined in a mesh shape. As described with reference to FIGS. 2 to 4, the metal thin wire 1 is formed with the metal film portion 3 over the entire length on the outer surface of the metal core portion 2 of the vertically long metal thin wire shown in the longitudinal section, A fine gap portion 4 is formed between the metal film portion 3 and the metal core portion 2. A metal film portion 3 is formed on the outer surface of the central metal core portion 2 as shown by another thin metal wire shown in the cross section. A fine gap portion 4 is formed between the thin metal piece 3 formed so as to be peeled off from the metal core portion 2 and the surface of the metal core portion 2.

  As shown in the heat pipe of this aspect, for example, the heating element is thermally connected to the outer surface of the container in the portion indicated by the dotted line in FIG. 5A where the mesh-like wick structure is disposed, When the radiating fin is thermally connected to the location, the working fluid sealed in the container evaporates due to the heat of the conducted heating element and moves to the part where the radiating fin is thermally connected through the mesh space. Then, it is cooled by the heat radiating fins and returns to the liquid phase, and returns to the heat absorbing portion where the heating element is thermally connected through the fine gap portion of the wick structure. Since the fine gap portion has a strong capillary force, the working fluid rapidly moves from the heat radiating portion to the heat absorbing portion, and so-called dryout does not occur even if the heat generation density of the heat generating element is high. On the other hand, by appropriately arranging the fine metal wires of the wick structure, the evaporated working fluid flows with high transmittance, that is, a state where the flow path resistance is small. FIG. 6 shows a partially enlarged cross section of another embodiment of the heat pipe. In FIG. 6, the wick structure is formed by laminating meshes.

  One aspect of the metal tube of the present invention includes a groove wall surface portion that forms a groove portion formed on the inner wall of the tube, and a groove metal film portion that forms a fine gap portion having a high capillary force between the groove wall surface portion. It is a metal tube provided with. That is, a groove metal film portion corresponding to the metal film portion is formed in the groove portion formed on the inner wall of the tube by oxidation / reduction in the same manner as the thin metal wire.

  FIG. 7 is a partial schematic cross-sectional view for explaining one embodiment of the metal tube of the present invention. FIG. 7A is a partial sectional view, and FIG. 7B is a diagram for explaining the details. As shown in FIG. 7 (a), generally V-shaped grooves are formed at equal intervals along the longitudinal direction of the tube on the inner wall of the tube. An acute angle portion of a groove portion having a V-shaped cross section formed on the inner wall of the tube exhibits a capillary force. In the present invention, the V-shaped groove formed in this manner is oxidized and reduced to further increase the capillary force. As shown in FIG. 7 (b), the metal tube 21 includes a groove metal film portion that forms a fine gap portion 24 having a high capillary force between the groove wall surface portions 22 and 22 forming the groove portion and the groove wall surface portion. 23. As shown in FIG. 7B, the fine gap portion 24 is formed over the entire two inclined surfaces of the groove portion.

  The metal tube can be manufactured by the following method. That is, a groove is formed along the longitudinal direction on the inner wall of the tube, and the groove is formed by oxidizing the inner wall of the tube having the groove at a predetermined temperature for a predetermined time (eg, 650 ° C., about 30 minutes). An oxide film is formed on the surface of the groove wall surface, and the groove wall surface portion on which the oxide film is formed is reduced at a predetermined temperature in a reducing gas atmosphere for a predetermined time (eg, 550 ° C., about 10 minutes). Then, a metal tube including a groove metal film portion that forms a fine gap portion having a high capillary force between the groove wall surface portion is manufactured.

Another aspect of the heat pipe of the present invention is a groove metal film that forms a fine gap portion having a high capillary force between a groove wall surface portion that forms a groove formed on the inner wall of the tube and the groove wall surface portion. A container made of a metal pipe with a portion,
Combining a plurality of fine metal wires having a metal core portion placed on the groove metal film portion of the metal tube and a metal film portion forming a fine gap portion having a high capillary force between the metal core portion. A formed wick structure;
It is a heat pipe provided with a working fluid sealed in a container.

  FIG. 8 is a partially enlarged view of another embodiment of the heat pipe of the present invention. As shown in FIG. 8, the inner wall of a tube as a container is provided with a fine gap portion having a high capillary force between the groove wall surface portion and the groove metal film portion described with reference to FIG. In addition, a wick structure composed of a plurality of fine metal wires having a fine gap portion with high capillary force between the metal core portion and the metal film portion described with reference to FIGS. 2 to 4 is combined. Yes. By appropriately arranging the grooves and the fine metal wires, it is possible to obtain a heat pipe having a high capillary force and at the same time a high permeability through which the gas-phase working fluid flows with a low flow resistance.

The heat pipe of this aspect can be manufactured by the following method. That is, a groove portion is formed along the longitudinal direction on the inner wall of the tube, the inner wall of the tube having the groove portion is oxidized at a predetermined temperature, and an oxide film is formed on the surface of the groove wall surface portion that forms the groove portion. A groove metal film portion that reduces a groove wall surface portion having an oxide film formed on the surface at a predetermined temperature in a gas atmosphere to form a fine gap portion having a high capillary force with the groove wall surface portion. Prepared metal tubes,
A metal core is formed by oxidizing a metal fine wire at a predetermined temperature to form an oxide film on the surface of the metal fine wire and reducing a metal fine wire having an oxide film formed on the surface at a predetermined temperature in a reducing gas atmosphere. And a plurality of fine metal wires provided with a metal film part that forms a fine gap part with high capillary force between the metal core part,
A plurality of fine metal wires are knitted into a net shape to prepare a wick structure, and the heat pipe is manufactured by placing the wick structure on the surface of the groove surface portion.

  According to the present invention, it is possible to provide a wick structure having a high capillary force and a high gas phase hydraulic fluid permeability, and a heat pipe using the same, which can be manufactured by a simple method.

FIG. 1 is a cross-sectional view illustrating one embodiment of a fine metal wire according to the present invention. FIG. 2 is a partial plan view for explaining a wick structure formed by combining a plurality of fine metal wires and knitting in a net shape. FIG. 3 is a partial cross-sectional view illustrating one embodiment of the wick structure. 4 is a schematic cross-sectional view illustrating details of the wick structure of FIG. FIG. 5 is a schematic diagram for explaining one embodiment of the heat pipe of the present invention. FIG. 6 is a schematic diagram illustrating another embodiment of the heat pipe of the present invention. FIG. 7 is a partial schematic cross-sectional view for explaining one embodiment of the metal tube of the present invention. FIG. 7A is a partial sectional view, and FIG. 7B is a diagram for explaining the details. FIG. 8 is a partially enlarged view of another embodiment of the heat pipe of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Metal thin wire 2 Metal core part 3 Metal film part 4 Fine gap part 10 Heat pipe 11 Container 12 Wick structure 21 Metal pipe 22 Groove wall surface part 23 Groove metal film part 24 Fine gap part

Claims (13)

A metal core portion, and a metal film portion that is made of the same metal as the metal core portion and forms a fine gap portion with high capillary force between the metal core portion,
The metal thin wire is expanded by oxidizing, and the expanded metal thin wire is reduced and contracted to stand up so that the metal flakes are peeled off from the metal core to form the metal film, and the metal core The metal core portion and the metal film portion are formed by oxidizing and reducing the fine metal wire at a temperature at which the fine gap portion can be formed between the surface of the portion and the metal film portion. A thin metal wire for wicks used in heat pipes .   A metal core part and a metal film part that is made of the same metal as the metal core part and forms a fine gap part having a high capillary force between the metal core part, and expands by oxidizing the fine metal wire The metal thin wire that has expanded is reduced and contracted to rise so that the metal flakes are peeled off from the metal core to form the metal film, and the surface of the metal core and the metal film Formed by combining a plurality of fine metal wires in which the metal core portion and the metal film portion are formed by oxidizing and reducing the fine metal wires at a temperature at which the fine gap portion can be formed. Wick structure.   The wick structure according to claim 2, wherein the plurality of fine metal wires are knitted in a net shape.   The wick structure according to claim 2, wherein the plurality of thin metal wires are superposed. A groove wall surface portion that forms a groove formed on the inner wall of the tube, and a groove metal film portion that is made of the same metal as the groove wall surface portion and forms a fine gap portion having a high capillary force between the groove wall surface portion and With
The tube is expanded by oxidizing, and the expanded tube is reduced and contracted to rise so that the metal flakes are peeled off from the groove wall surface portion to form the groove metal film portion, and the groove wall surface portion The groove wall surface portion and the groove metal film portion are formed by oxidizing and reducing the tube at a temperature at which the fine gap portion can be formed between the surface and the groove metal film portion. Metal pipe for containers used for heat pipes . The metal tube for a container used for a heat pipe according to claim 5, wherein the groove wall surface portion and the groove metal film portion are formed on at least a part of an inner wall of the tube.   A groove wall surface portion that forms a groove formed on the inner wall of the tube, and a groove metal film portion that is made of the same metal as the groove wall surface portion and forms a fine gap portion having a high capillary force between the groove wall surface portion and The tube is expanded by oxidizing, and the expanded tube is reduced and contracted to rise so that the metal flakes are peeled off from the groove wall surface portion to form the groove metal film portion, and the groove The groove wall surface portion and the groove metal film portion are formed by reducing the tube after being oxidized at a temperature at which the fine gap portion can be formed between the surface of the wall surface portion and the groove metal film portion. A heat pipe comprising a container made of a metal tube and a working fluid sealed in the container.   A sealed metal container, a metal core disposed in the container, and a metal film made of the same metal as the metal core and forming a fine gap between the metal core with high capillary force The metal thin wire is expanded by oxidizing, and the expanded metal thin wire is reduced and contracted to rise so that the metal flakes are peeled off from the metal core to form the metal film portion The metal core portion and the metal film portion are reduced by oxidizing and then reducing the fine metal wire at a temperature at which the fine gap portion can be formed between the surface of the metal core portion and the metal film portion. A heat pipe comprising a wick structure formed by combining a plurality of thin metal wires formed with a working fluid sealed in the container. A groove wall surface portion that forms a groove formed on the inner wall of the tube, and a groove metal film portion that is made of the same metal as the groove wall surface portion and forms a fine gap portion having a high capillary force between the groove wall surface portion and The tube is expanded by oxidizing, and the expanded tube is reduced and contracted to rise so that the metal flakes are peeled off from the groove wall surface portion to form the groove metal film portion, and the groove The groove wall surface portion and the groove metal film portion are formed by reducing the tube after being oxidized at a temperature at which the fine gap portion can be formed between the surface of the wall surface portion and the groove metal film portion. A container made of metal pipes,
A metal core placed on the groove metal film part of the metal tube, and a metal made of the same metal as the metal core part and forming a fine gap portion having a high capillary force between the metal core part And a metal part is expanded by oxidizing the metal thin line, and the expanded metal thin line is reduced and contracted to stand up so that the metal flakes are peeled off from the metal core part, and the metal film part is The metal core portion and the metal film are formed and reduced after oxidizing the fine metal wires at a temperature at which the fine gap portion can be formed between the surface of the metal core portion and the metal film portion. And a wick structure formed by combining a plurality of fine metal wires formed with parts,
A heat pipe provided with a working fluid enclosed in the container. The metal thin wire is expanded by oxidizing, and the expanded metal thin wire is reduced and contracted to rise so that the metal flakes are peeled off from the metal core to form a metal film portion. Capillary force between the metal core part and the metal core part is reduced by oxidizing the thin metal wire at a temperature at which a fine gap can be formed between the surface and the metal film part. The manufacturing method of the thin metal wire for wicks used for a heat pipe which forms the said metal film part which forms the said fine space | gap part with high height. A mesh is formed by knitting a plurality of fine metal wires into a net,
The metal thin wire is expanded by oxidizing, and the expanded metal thin wire is reduced and contracted to rise so that the metal flakes are peeled off from the metal core to form a metal film portion. At a temperature at which a fine gap can be formed between the surface and the metal film part, the mesh is oxidized to form an oxide film on the surface of the metal fine wire,
The mesh having an oxide film formed on the surface is reduced at a predetermined temperature under a reducing gas atmosphere, and the capillary core force is high between the metal core portion of the metal thin wire and the metal core portion. The manufacturing method of the wick structure which forms the said metal film part which forms a fine clearance part. Forming a groove along the longitudinal direction on the inner wall of the tube,
The tube is expanded by oxidizing, and the expanded tube is reduced and contracted to rise so that the metal flakes are peeled off from the groove wall surface portion to form a groove metal film portion, and the surface of the groove wall surface portion Oxidizing the inner wall of the tube provided with the groove at a temperature capable of forming a fine gap with the groove metal film, and forming an oxide film on the surface of the groove wall surface forming the groove;
The groove metal that reduces the groove wall surface portion having an oxide film formed on the surface thereof at a predetermined temperature in a reducing gas atmosphere to form the fine gap portion having a high capillary force between the groove wall surface portion and the groove wall surface portion. The manufacturing method of the metal tube for containers used for a heat pipe which manufactures the metal tube provided with the film | membrane part. Forming a groove along the longitudinal direction on the inner wall of the tube,
The tube is expanded by oxidizing, and the expanded tube is reduced and contracted to rise so that the metal flakes are peeled off from the groove wall surface portion to form the groove metal film portion, and the groove wall surface portion An oxide film is formed on the surface of the groove wall surface forming the groove by oxidizing the inner wall of the tube having the groove at a temperature at which the fine gap can be formed between the surface and the groove metal film. Forming,
The groove metal that reduces the groove wall surface portion having an oxide film formed on the surface thereof at a predetermined temperature in a reducing gas atmosphere to form the fine gap portion having a high capillary force between the groove wall surface portion and the groove wall surface portion. Prepare a metal tube with a membrane part,
The metal thin wire is expanded by oxidizing, and the expanded metal thin wire is reduced and contracted to rise so that the metal flakes are peeled off from the metal core to form a metal film portion. An oxide film is formed on the surface of the fine metal wire by oxidizing the fine metal wire at a temperature capable of forming a fine gap between the surface and the metal film portion;
The fine gap portion having a high capillary force between the metal core portion and the metal core portion by reducing the metal thin wire having an oxide film formed on the surface at a predetermined temperature in a reducing gas atmosphere. Preparing a plurality of fine metal wires provided with the metal film part forming,
The wick structure is prepared by knitting the plurality of fine metal wires into a net shape,
A heat pipe manufacturing method for manufacturing a heat pipe by placing the wick structure on a surface of the groove surface portion.

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