Wick, plate type heat pipe and container
A plate type thin heat pipe comprises: a group of wire members comprising a plurality of first metal wire members placed in a same plane in parallel with a prescribed distance spaced out, and a plurality of second metal wire members placed in a same plane in parallel with a prescribed distance spaced out and placed so as to cross the plurality of first metal wire members; a container having a hollow portion which is reduced in inner pressure and hermetically sealed comprising an upper plate member and a lower plate member placed face to face, each of which is made of thin copper plate, formed in such a manner that each of the upper plate member and the lower plate member contacts the group of wire members, and the group of wire members are sandwiched by the upper and lower plate members, and water as a working fluid received in the container.
[0001] This application is a divisional of U.S. patent application Ser. No. 09/655,664, filed Sep. 6, 2000, the entire disclosure of which is hereby incorporated by reference, and which claims priority to Japanese Application Nos. 1999-252748, filed on Sep. 7, 1999, and 1999-252749, filed on Sep. 7, 1999. This application is related to U.S. Non-Provisional application Ser. No. 10/______ , filed on even date herewith (having attorney docket number KAWAW6.001DV2), the entire disclosure of which is hereby incorporated by reference.
BACKGROUND OF THE INVENTION[0002] 1. Field of the Invention
[0003] The present invention relates to a plate type heat pipe, wick and container used for cooling electronic devices.
[0004] 2. Description of the Related Art
[0005] As one of the means to effectively dissipate the heat generated from semiconductor chips in the electronic devices which has been increasing, there is proposed a heat pipe. In particular, a plate type heat pipe is perceived to be effective among various heat pipes because the heat receiving surface thereof to the surface of the chip can be secured and the function of heat diffusion is excellent.
[0006] The heat pipe comprises a hermetically sealed container which has a hollow portion therein, and the pressure within the container is reduced to be vacuum. An appropriate amount of liquid is enclosed within the container as a working fluid. When heat is received in an outer portion of the container, the fluid existing in the corresponding portion within the container to the outer portion to which the heat is received evaporates and absorbs the latent heat of the evaporation. The vapor flows to every corner of the container and fills the whole inner side of the container due to the difference in pressure. The flowed vapor condenses at the inner surface of the container except the heat receiving portion to discharge the latent heat of the evaporation. The condensed fluid returns to the evaporating portion by means of a fluid circulating mechanism which is arranged in the inner surface of the container and called as wick comprising mesh, wire or the like. Thus circulated fluid evaporates again in the heat receiving portion. The above-mentioned circulation of the fluid-vapor-fluid is repeated, and as a result, the heat is diffused and transferred to the whole of the container.
[0007] The working fluid is poured into the container, and then gas in the container is removed while the working fluid is remained therein and the container is hermetically sealed in the final stage to complete the fabrication of the heat pipe. The heat pipe includes a portion to be sealed in either case that the working fluid is vaporized to remove the gas from the interior of the container, or that the gas is removed by a vacuum pump from the container. The portion to be sealed is kept opened toward outside until the final stage of the fabrication of the heat pipe.
[0008] A heat pipe comprises in general a pipe-shaped heat pipe in which one of the end portions becomes the portion to be sealed. After pouring the working fluid into the container under vacuum condition, or after pouring the working fluid and removing the gas, the above-mentioned end portion is in general caulked and then welded to be hermetically sealed.
[0009] However, when the heat pipe comprises a plate type heat pipe, it is impossible to apply the above-mentioned method to seal the container. FIG. 14 shows a conventional portion to be sealed in the plate type heat pipe. As shown in FIG. 14, a hexahedron body having six flat surfaces is formed by arranging and brazing an upper plate member 104, a lower plate member 105 and side plate members 106. In the above case, a small tube 107 is inserted into the side plate member 106 to form the portion to be sealed.
[0010] FIG. 11 shows a conventional plate type heat pipe. The plate type heat pipe shown in FIG. 11 comprises an aluminum container 101 which is formed by extrusion. However, although the aluminum container shown in FIG. 11 can be formed by extrusion, it is difficult to form the container shown in FIG. 11 which is made of copper by means of extrusion. In addition, water is an excellent working fluid. However, there is a problem in which water cannot be used as working fluid in the container made of aluminum. More specifically, aluminum reacts with water to deteriorate the function of the heat pipe.
[0011] In order to solve the above-mentioned problem, there is proposed a plate type heat pipe as shown in FIG. 12 or FIG. 13 which comprises a container having a hollow portion formed by an upper plate member 108 and a lower plate member 109 in which a mesh 110 is inserted therein. Since the container shown in FIG. 12 is made of copper, water can be used as the working fluid. However, in the plate type heat pipe shown in FIG. 12, there is a problem in which it is difficult to insert the mesh stably in the container, thus producing the heat pipes with different property.
[0012] Furthermore, a conventional wick comprising mesh, braid or wire has the following problem. More specifically, when the wire is used as shown in FIG. 6, since the acute angle portion designated by A in the cross-sectional view which is formed by the inner surface of the container and the outer surface of the wire exists continuously and uniformly along the axis of the wire, it can be expected that the working fluid effectively circulates. However, even if the wire is received within the container, it is very difficult to securely fix the wire on the inner surface of the container in view of the structure of the container so as to form the acute angle portion therebetween. When the wire is not securely fixed on the inner surface of the container, for example, the side surface of the wire is partly contacted with the inner surface of the container, the wire does not effectively function as the wick. Furthermore, in the plate type heat pipe, it is required that the working fluid flows not along only one direction, but in all direction across the plane, depending on the manner in which the heat pipe is positioned.
[0013] Furthermore, in case of the wick comprising the mesh or the braid, since the mesh or the braid has a first element running in the first direction and a second element running in the second direction perpendicular to the first direction, contrary to the wire in which the circulating direction of the working fluid is uniform along the axis of the wire, the above-mentioned second element disturbs the flow of the working fluid along the axis of the first element.
[0014] In addition, there is the following problem in the plate type heat pipe using the above-mentioned conventional wick.
[0015] More specifically, as described above, in the technical field of cooling semiconductor chip or the like mounted in the electronic device, there is a tendency in which a whole electronic device is downsized and the density of the integration of the chip becomes higher to cause the density of generated heat to remarkably increase. However, the conventional wick does not effectively function.
[0016] Furthermore, the conventional portion to be sealed has the following problem. More specifically, as described above, in the technical field of cooling semiconductor chip or the like mounted in the electronic device, there is a tendency in which a whole electronic device is downsized and the density of the integration of the chip becomes higher. Accordingly, the plate type heat pipe has a large restriction in the thickness of the plate type heat pipe. For example, when the total height of the heat pipe is 1 mm, the thickness of the plate member of the heat pipe is 0.2 mm, which is a general size of this kind of the plate type heat pipe, the outer diameter of the small tube 107 inserted in the side plate member as shown in FIG. 14 is 0.6 mm&phgr; and the inner diameter thereof is 0.4 mm&phgr;. It is therefore impossible to pour the working fluid into the container by the needle of the injector commercially used. Furthermore, since the small tube is inserted into the side plate member of the container, the small tube protrudes out of the container. In addition, since the small tube is positioned in the side portion of the container, the gas remains in the corner of the container when the gas is removed.
[0017] The object of the present invention is therefore to provide a container, a plate type thin heat pipe and a wick which may effectively cool semiconductor chip or the like in the electronic device with remarkably increasing heat generating density and enable to easily seal the portion to be sealed.
SUMMARY OF THE INVENTION[0018] To solve the problems in the conventional art, the present inventors have been studying hard. As a result, the following findings are obtained. More specifically, it is important in a wick that the wick has a capillary power. The capillary power can be obtained in general by placing mesh along the inner wall surface of the tube. It is the most ideal structure of the wick in which the acute angle portion in the cross-sectional view, for example as described above with reference to FIG. 6, which is formed by the inner surface of the container and the outer surface of the wire exists continuously and uniformly along the axis of the wire. Even in FIG. 6, the portion to effectively circulate the working fluid is the portion designated by A. More specifically, since the mesh or the braid comprises an assembly of wires in microscopic analysis, the portion A may be formed when the wire is fixed on the inner wall surface of the heat pipe so as to effectively circulate the working fluid.
[0019] Accordingly, it has been found that when a plurality of protruding portions are arranged in one of the inner wall surfaces of the container to fix the mesh or the like to the other inner wall surface of the container, the space for the vaporized working fluid may be secured and the above-mentioned acute angle portion may be obtained between the inner wall surface of the container and the outer surface of wire member which has a circular cross section, since the mesh is closely attached on the inner wall surface of the container, thus effectively circulating the working fluid.
[0020] In addition it has been found that when a mesh comprising a combined wire members running in X direction and Y direction in a lattice shape are closely attached on the inner wall surface of the container, the above-mentioned acute angle portion may be obtained between the inner wall surface of the container and the outer surface of wire member which has a circular cross section, thus effectively circulating the working fluid.
[0021] Furthermore, it has been found that when a recessed portion is formed in a central portion of a thin copper plate in such manner that there is a difference in level between the outer peripheral portion and the central portion, and a passage connecting to outside is formed in a corner portion as a portion to be sealed, the container may be hermetically sealed only by caulking the corner portion, and in addition, since the portion to be sealed is formed in the corner portion, the gas is hardly remained within the container in case of removing the gas.
[0022] The present invention was made based on the above-mentioned findings.
[0023] The first embodiment of the wick of the present invention comprises a flat plate member and a wire member wound around said flat plate member, said wick being received within a container having a hollow portion of a plate type thin heat pipe, inner pressure of which container is reduced and which is hermetically sealed.
[0024] The second embodiment of the wick of the present invention comprises a wick, wherein said flat plate member comprises a unit of punched metal plates formed by combining two punched metal plates in which at least one of said punched metal plates have a plurality of protruding portions, and said two punched metal plates are placed face to face with a distance corresponding to a height of said protruding portion.
[0025] The first embodiment of the plate type thin heat pipe of the present invention comprises: (1) a plurality of metal wire members placed in a same plane in parallel with a prescribed distance spaced out; (2) a container having a hollow portion which is reduced in inner pressure and hermetically sealed comprising an upper plate member and a lower plate member placed face to face, each of which is made of thin copper plate, formed in such a manner that each of said upper plate member and said lower plate member contacts said wire members, and said wire members are sandwiched by said upper and lower plate members; and (3) water as a working fluid received in said container.
[0026] The second embodiment of the plate type thin heat pipe of the present invention comprises: (1) a group of wire members comprising a plurality of first metal wire members placed in a same plane in parallel with a prescribed distance spaced out, and a plurality of second metal wire members placed in a same plane in parallel with a prescribed distance spaced out and placed so as to cross said plurality of first metal wire members; (2) a container having a hollow portion which is reduced in inner pressure and hermetically sealed comprising an upper plate member and a lower plate member placed face to face, each of which is made of thin copper plate, formed in such a manner that each of said upper plate member and said lower plate member contacts said group of wire members, and said group of wire members are sandwiched by said upper and lower plate members; and (3) water as a working fluid received in said container.
[0027] The third embodiment of the plate type thin heat pipe of the present invention comprises: (1) a container having a hollow portion which is reduced in inner pressure and hermetically sealed, formed by an upper plate member comprising a thin copper plate and a lower plate member comprising a thin copper plate; (2) a wick comprising a flat plate member and a wire member wound around said flat plate member, received in said container; and (3) a working fluid received in said container.
[0028] The fourth embodiment of the plate type thin heat pipe of the present invention comprises: (1) a container having a hollow portion which is reduced in inner pressure and hermetically sealed, formed by an upper plate member comprising a thin copper plate and a lower plate member comprising a thin copper plate; (2) a wick formed by being arranged on an inner surface of one of said upper plate member and said lower plate member, which is positioned within said container; (3) a working fluid received in said container.
[0029] The fifth embodiment of the plate type thin heat pipe of the present invention comprises: (1) a container having a hollow portion which is reduced in inner pressure and hermetically sealed, formed by an upper plate member comprising a thin copper plate and a lower plate member comprising a thin copper plate, a plurality of protruding portions being formed on an inner surface of said upper plate member or said lower plate member; (2) a wick comprising a flat plate member and a wire member wound around said flat plate member, received in said container in such a manner that said wick is pressed by said plurality of protruding portions to an opposing inner surface of said container; (3) a working fluid received in said container.
[0030] The sixth embodiment of the plate type thin heat pipe of the present invention comprises: (1) a container having a hollow portion which is reduced in inner pressure and hermetically sealed, formed by an upper plate member comprising a thin copper plate and a lower plate member comprising a thin copper plate; (2) a wick comprising a unit of punched metal plates formed by combining two punched metal plates in which at least one of said punched metal plates have a plurality of protruding portions, and said two punched metal plates are placed face to face with a distance corresponding to a height of said protruding portion and a wire member wound around said unit of punched metal plates; and (3) a working fluid received in said container.
[0031] The seventh embodiment of the plate type thin heat pipe of the present invention comprises a plate type thin heat pipe, wherein another wire member is further arranged in such manner that said another wire member crosses said wire member arranged on both of outer surfaces of said unit of punched metal plates of said wick.
[0032] The eighth embodiment of the plate type thin heat pipe of the present invention comprises: (1) a group of wire members comprising a plurality of first metal wire members placed in a same plane in parallel with a prescribed distance spaced out, and a plurality of second metal wire members placed in a same plane in parallel with a prescribed distance spaced out and placed so as to cross said plurality of first metal wire members; (2) a container having a hollow portion formed by an upper plate member made of thin copper plate, in a central portion of which a recessed portion is formed to receive said group of wire members and in a corner portion of which a passage connecting said recessed portion to outside is formed, and a flat lower pate member made of thin copper plate, outer peripheral portion of which are joined and said passage is caulked so as to be hermetically sealed and inner pressure thereof is reduced, said group of wire members being received in said hollow portion and each of inner surface of said upper plate member and said lower plate member contacting said group of wire members; (3) water as a working fluid received in said container.
[0033] The ninth embodiment of the plate type thin heat pipe of the present invention comprises: (1) a container having a hollow portion formed by an upper plate member made of thin copper plate, in a central portion of which a recessed portion is formed and in a corner portion of which a passage connecting said recessed portion to outside is formed, and a flat lower pate member made of thin copper plate, outer peripheral portion of which are joined and said passage is caulked so as to be hermetically sealed and inner pressure thereof is reduced; (2) a wick comprising a flat plate member and a wire member wound around said flat plate member, received in said container; (3) a working fluid received in said container.
[0034] The tenth embodiment of the plate type thin heat pipe of the present invention comprises: (1) a container having a hollow portion formed by an upper plate member made of thin copper plate, in a central portion of which a recessed portion is formed and in a corner portion of which a passage connecting said recessed portion to outside is formed, and a flat lower pate member made of thin copper plate, a plurality of protruding portions being formed on an inner surface of said upper plate member or said lower plate member, outer peripheral portions of which are joined and said passage is caulked so as to be hermetically sealed and inner pressure thereof is reduced; (2) a wick comprising a flat plate member and a wire member wound around said flat plate member, received in said container in such a manner that said wick is pressed by said plurality of protruding portions to an opposing inner surface of said container; and (3) a working fluid received in said container.
[0035] The eleventh embodiment of the plate type thin heat pipe of the present invention comprises: (1) a container having a hollow portion formed by an upper plate member made of thin copper plate, in a central portion of which a recessed portion is formed and in a corner portion of which a passage connecting said recessed portion to outside is formed, and a flat lower pate member made of thin copper plate, outer peripheral portions of which are joined and said passage is caulked so as to be hermetically sealed and inner pressure thereof is reduced; (2) a wick comprising a unit of punched metal plates formed by combining two punched metal plates in which at least one of said punched metal plates have a plurality of protruding portions, and said two punched metal plates are placed face to face with a distance corresponding to a height of said protruding portion and a wire member wound around said unit of punched metal plates; (3) a working fluid received in said container.
[0036] The twelfth embodiment of the plate type thin heat pipe of the present invention comprises a plate type thin heat pipe, wherein another wire member is further arranged in such manner that said another wire member crosses said wire member arranged on both of outer surfaces of said unit of punched metal plates of said wick.
[0037] The thirteenth embodiment of the plate type thin heat pipe of the present invention comprises a plate type thin heat pipe, wherein said upper plate member is integrally formed as one piece member by press-working.
[0038] The first embodiment of the container of the present invention comprises a container of a plate type heat pipe formed by combining a flat plate having a recessed portion in a central portion thereof and a passage connecting to outside in a corner portion of an outer peripheral portion thereof, and another flat plate, then brazing said outer peripheral portion of said flat plate to said another flat plate, and caulking said passage to form a hermetically sealed hollow portion.
[0039] The second embodiment of the container of the present invention comprises a container, wherein said flat plate and said another flat plate have corresponding recessed portions in respective central portions and corresponding passages in respective corner portions.
[0040] One embodiment of the method for manufacturing a plate type thin heat pipe of the present invention comprises steps of:
[0041] (1) preparing metal wire member placed in a same plane in parallel with a prescribed distance spaced out;
[0042] (2) sandwiching said wire member by a copper thin upper plate member and a copper thin lower plate member in such manner that solder is applied on portions of said upper plate member and lower plate member with which said wire member contacts to provisionally fabricate a container;
[0043] (3) applying a heat treatment to thus provisionally fabricated container at a prescribed temperature to form a hermetically sealed container in which said wire member, said upper plate member and said lower plate member are integrated as a one piece member;
[0044] (4) reducing an inner pressure of said container, and filling water as a working fluid.
[0045] Other embodiment of the wick of the present invention comprises a wick, wherein said flat plate member of said wick comprises a circular shaped or a polygonal shaped plate with notches or columns arranged in the end portion thereof, said wire member being wound with the use of said notches or columns as turn-around points and arranged on one surface of said flat plate member.
[0046] Other embodiment of the wick of the present invention comprises a wick, wherein said flat plate member of said wick comprises a punched metal having a plurality of punched holes.
[0047] Other embodiment of the wick of the present invention comprises a wick, wherein another wire member is further arranged in such manner that said another wire member crosses said wire member arranged on both of outer surfaces of said unit of punched metal plates of said wick.
[0048] Other embodiment of the plate type thin heat pipe of the present invention comprises a plate type thin heat pipe, wherein mesh is further provided between said wire member and said upper plate member or said lower plate member, between said wire member and said another wire member, and between said group of wire members and said upper plate member or said lower plate member.
[0049] Other embodiment of the plate type thin heat pipe of the present invention comprises a plate type thin heat pipe, wherein said flat plate member of said wick comprises a circular shaped or a polygonal shaped plate with notches or columns arranged in the end portion thereof, said wire member being wound with the use of said notches or columns as turn-around points and arranged on one surface of said flat plate member.
[0050] Other embodiment of the plate type thin heat pipe of the present invention comprises a wick, wherein said flat plate member of said wick comprises a circular shaped or a polygonal shaped plate, said wire member being wound on both surfaces of said plate member.
[0051] Other embodiment of the plate type thin heat pipe of the present invention comprises a plate type thin heat pipe, wherein said flat plate member of said wick comprises a punched metal having a plurality of punched holes.
[0052] Other embodiment of the plate type thin heat pipe of the present invention comprises a plate type thin heat pipe, wherein another wire member is further arranged in such manner that said another wire member crosses said wire member arranged on both of outer surfaces of said unit of punched metal plates of said wick.
[0053] Other embodiment of the plate type thin heat pipe of the present invention comprises a plate type thin heat pipe, wherein at least one of said upper plate member and said lower plate member have a recessed portion in a central portion, and said upper plate member and said lower plate member are fitted and outer peripheral portions are joined to form said container including said hollow portion.
[0054] Other embodiment of the plate type thin heat pipe of the present invention comprises a plate type thin heat pipe, wherein said unit of punched metal plates comprises a circular shaped or a polygonal shaped plate, and said wire member is arranged on both of outer surfaces of said unit of punched metal plates.
BRIEF DESCRIPTION OF THE DRAWINGS[0055] FIG. 1 is a view to show elements of one of the embodiment of the plate type heat pipe of the present invention;
[0056] FIG. 2 is a schematic view to show other arrangement of the wire member shown in FIG. 1;
[0057] FIG. 3 is a schematic perspective view showing one embodiment of the wick of the present invention;
[0058] FIG. 4 is a schematic view of other embodiment of the wick of the present invention;
[0059] FIG. 5 is a schematic cross-sectional view showing one embodiment of the plate type heat pipe of the invention;
[0060] FIG. 6 is a cross-sectional view showing a contact portion between one plate member and wire member;
[0061] FIG. 7 is a schematic cross-sectional view showing other embodiment of the plate type heat pipe of the invention;
[0062] FIG. 8 is a schematic view of other embodiment of the wick of the present invention;
[0063] FIG. 9 is a schematic perspective view showing a portion to be sealed in the container of the invention;
[0064] FIG. 10 is a plan view showing a lower plate member including a portion to be sealed shown in FIG. 9;
[0065] FIG. 11 is a schematic perspective view showing a conventional aluminum container;
[0066] FIG. 12 is a schematic cross-sectional view showing a conventional heat pipe;
[0067] FIG. 13 is a schematic cross-sectional view showing a conventional heat pipe; and
[0068] FIG. 14 is a view to show elements of a conventional plate type heat pipe including a portion to be sealed.
[0069] FIG. 15 illustrates a wick comprising a flat plate member and a wire member wound around the flat plate member.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT[0070] The present invention is described with reference to the accompanying drawings.
[0071] One embodiment of the plate type thin heat pipe of the present invention comprises (1) a plurality of metal wire members placed in a same plane in parallel with a prescribed distance spaced out, (2) a container having a hollow portion which is reduced in inner pressure and hermetically sealed comprising an upper plate member and a lower plate member placed face to face, each of which is made of thin copper plate, formed in such a manner that each of said upper plate member and said lower plate member contacts said wire members, and said wire members are sandwiched by said upper and lower plate members, and (3) water as a working fluid received in said container.
[0072] Furthermore, other embodiment of the plate type thin heat pipe of the present invention comprises (1) a group of wire members comprising a plurality of first metal wire members placed in a same plane in parallel with a prescribed distance spaced out, and a plurality of second metal wire members placed in a same plane in parallel with a prescribed distance spaced out and placed so as to cross said plurality of first metal wire members, (2) a container having a hollow portion which is reduced in inner pressure and hermetically sealed comprising an upper plate member and a lower plate member placed face to face, each of which is made of thin copper plate, formed in such a manner that each of said upper plate member and said lower plate member contacts said group of wire members, and said group of wire members are sandwiched by said upper and lower plate members, and (3) water as a working fluid received in said container.
[0073] In addition, in the plate type thin heat pipe of the present invention, mesh may be further provided between said wire member and said upper plate member or said lower plate member, between said wire member and said another wire member, and between said group of wire members and said upper plate member or said lower plate member.
[0074] The above-mentioned embodiments of the plate type thin heat pipe of the present invention are described in more detail. As shown in FIG. 1, a plurality of wire members 2 are arranged in parallel each other, for example. Solder is applied in advance on the portions of the thin flat plates with which the wire members contact, and the wire members arranged in parallel are sandwiched by the two copper thin flat plates 1, 3. Thus prepared wire members and flat plates are introduced into a furnace to obtain the container as substantially shown in FIG. 11 without limiting the material of the container to aluminum. Since the wire member positioned in the outer most end forms the outer wall of the container, a square wire member may be used in stead of a round wire member.
[0075] According to the above-mentioned container of the present invention, contrary to the conventional container shown in FIG. 11 in which each of partition members vertically extend from the lower member to form a corner of right angles, the outer surface of the round wire member 2 and the flat plate 2, 3 forms acute angle, thus the round wire member per se functions as a wick to reduce the numbers of the parts which is favorable.
[0076] Furthermore, in case of the conventional container formed by extrusion shown in FIG. 11, the heat transfer along the X direction (i.e., the direction across the partition member of the container) is inferior to the heat transfer along the Y direction (i.e., the direction along the partition member). On the other hand, in the above-mentioned container of the present invention, for example as shown in FIG. 2(b), since the wire members 2 are intermittently arranged, the heat transfer property in the X direction can be improved together with that in the Y direction. In this case, when the mesh 8 is interposed between one of the plate member 7 and the wire member 9, as shown in FIG. 4, a required strength can be provided with the container.
[0077] As shown in FIG. 3, the group of the wire members 5 arranged in parallel each other are placed in such manner as crossing the other group of the wire members 5 arranged in parallel each other, and then the two groups of the wire members are sandwiched by the plate member 4, 6 to form the container of the plate type thin heat pipe. In the above-mentioned container, the space along the X direction is connected to the space along the Y direction without intermittently placing the wire members.
[0078] Furthermore, as described above, in the structure in which mesh is further interposed between the group of wire members 9 and the plate member 7, the wire member 9 functions as a part of the wick, and in addition, functions to fix the mesh 8 as the main wick to one surface of the plate member 7 and secure the passage for the vaporized fluid.
[0079] In addition, other embodiment of the plate type thin heat pipe of the present invention may comprises: (1) a container having a hollow portion which is reduced in inner pressure and hermetically sealed, formed by an upper plate member comprising a thin copper plate and a lower plate member comprising a thin copper plate, a plurality of protruding portions being formed on an inner surface of said upper plate member or said lower plate member; (2) a wick comprising a flat plate member and a wire member wound around said flat plate member, received in said container in such a manner that said wick is pressed by said plurality of protruding portions to an opposing inner surface of said container; and (3) a working fluid received in said container.
[0080] As shown in FIG. 5, a plurality of protruding portions 12 are provided with one of the flat plate 11 of two flat plates, and two flat plates are placed face to face to form the container. In this case, when one of the flat plate is formed so as to have a recessed portion in the central portion thereof, the recessed portion forms the inner space of the container. In particular, in case of the very thin type of container required, the recessed portion can be easily formed by press-working. The above-mentioned protruding portions 12 can be formed together with the recessed portion. The protruding portions 12 are provided on all the surface of the recessed portion 11 in an arrangement of equilateral triangle, for example. The shape of the protruding portion may be cylindrical or square pole. The height of the protruding portion is prepared so as to be equal to the difference between the thickness of the layered meshes received in the container and the distance from the inner surface of one of the plate member to the inner surface of the other plate member of the container.
[0081] Two flat plates 11, 14 with the recessed portion and the protruding portions respectively formed according to the above are placed face to face, then, the layered meshes 13 are interposed therebetween, and then the outer peripheral portions are brazed so that the container is hermetically sealed. At the same time, a small tube is interposed in a part of the outer peripheral portions. A working fluid is injected into the container, and the air is removed through the small tube. Then, the small tube is caulked, thus the plate type thin heat pipe is prepared.
[0082] The protruding portion 12 functions to press the meshes against the inner surface of the flat plate, and at the same time, according to the protruding portions, the passage space for flowing the vaporized fluid therethrough is secured. Furthermore, the portion of the wick most effectively functioning to circulate the working fluid is the portion of the acute angle formed by the inner wall of the container and the outer surface of the circular wire member as shown above in the cross-section. According to the plate type heat pipe of the present invention, since the mesh is surely and closely pressed to the inner wall of the container, the working fluid is effectively circulated.
[0083] The structure of the wick is not limited to the above-mentioned mesh. The structure of the wick may comprises a group of wire members or a group of braid. With those wick, the same effect as described above can be obtained.
[0084] Furthermore, in addition to the group of protruding portions described above, a second group of protruding portions are preferably provided, the height of which is equal to the distance between the inner surface of one of the flat plate and the inner surface of the other flat plate of the container. The second group of protruding portions thus formed function to reinforce the strength of the container. The density of the second group of the protruding portions may be lower than that of the first group of the protruding portions. However, when the wick structure comprises a mesh or layered meshes, the punched holes corresponding to the protruding portions in shape and arrangement are preferably prepared in advance in the mesh or the layered meshes. In this case, when the wick structure is sandwiched by the two flat plates, the tip ends of the second group of protruding portions contact with the inner surface of the opposing flat plate. When the above-mentioned tip ends are brazed in the same manner as the outer peripheral portions, the walls of the container can be prevented from being deformed even when the inner pressure of the heat pipe becomes higher than the pressure of the open air.
[0085] Then, embodiments of the wick of the present invention is described. One embodiment of the wick of the present invention comprises a flat plate member and a wire member wound around said flat plate member, as illustrated in FIG. 15, for example. The wick may be received within a container having a hollow portion of a plate type thin heat pipe, inner pressure of which container is reduced and which is hermetically sealed.
[0086] Furthermore, other embodiment of the wick of the present invention comprises a wick, wherein said flat plate member comprises a unit of punched metal plates formed by combining two punched metal plates in which at least one of said punched metal plates have a plurality of protruding portions, and said two punched metal plates are placed face to face with a distance corresponding to a height of said protruding portion.
[0087] In addition, other embodiment of the wick of the present invention comprises a wick, wherein said flat plate member of said wick comprises a circular shaped or a polygonal shaped plate with notches or columns arranged in the end portion thereof, said wire member being wound with the use of said notches or columns as turn-around points and arranged on one surface of said flat plate member.
[0088] In addition, other embodiment of the wick of the present invention comprises a wick, wherein said flat plate member of said wick comprises a punched metal having a plurality of punched holes.
[0089] In addition, other embodiment of the wick of the present invention comprises a wick, wherein another wire member is further arranged in such manner that said another wire member crosses said wire member arranged on both of outer surfaces of said unit of punched metal plates of said wick.
[0090] Then, other embodiments of the plate type thin heat pipe of the present invention are described.
[0091] Other embodiment of the plate type thin heat pipe of the present invention comprises: (1) a container having a hollow portion which is reduced in inner pressure and hermetically sealed, formed by an upper plate member comprising a thin copper plate and a lower plate member comprising a thin copper plate; (2) a wick comprising a flat plate member and a wire member wound around said flat plate member, received in said container; and (3) a working fluid received in said container.
[0092] In addition, other embodiment of the plate type thin heat pipe of the present invention comprises: (1) a container having a hollow portion which is reduced in inner pressure and hermetically sealed, formed by an upper plate member comprising a thin copper plate and a lower plate member comprising a thin copper plate; (2) a wick formed by being arranged on an inner surface of one of said upper plate member and said lower plate member, which is positioned within said container; (3) a working fluid received in said container.
[0093] In addition, other embodiment of the plate type thin heat pipe of the present invention comprises: (1) a container having a hollow portion which is reduced in inner pressure and hermetically sealed, formed by an upper plate member comprising a thin copper plate and a lower plate member comprising a thin copper plate; (2) a wick comprising a unit of punched metal plates formed by combining two punched metal plates in which at least one of said punched metal plates have a plurality of protruding portions, and said two punched metal plates are placed face to face with a distance corresponding to a height of said protruding portion and a wire member wound around said unit of punched metal plates; and (3) a working fluid received in said container.
[0094] Furthermore, the plate type thin heat pipe of the present invention may comprises a plate type thin heat pipe, wherein another wire member is further arranged in such manner that said another wire member crosses said wire member arranged on both of outer surfaces of said unit of punched metal plates of said wick.
[0095] In addition, the plate type thin heat pipe of the present invention may comprises a plate type thin heat pipe, wherein said flat plate member of said wick comprises a circular shaped or a polygonal shaped plate with notches or columns arranged in the end portion thereof, said wire member being wound with the use of said notches or columns as turn-around points and arranged on one surface of said flat plate member.
[0096] In addition, the plate type thin heat pipe of the present invention may comprises a wick, wherein said flat plate member of said wick comprises a circular shaped or a polygonal shaped plate, said wire member being wound on both surfaces of said plate member.
[0097] In addition, the plate type thin heat pipe of the present invention may comprises a plate type thin heat pipe, wherein said flat plate member of said wick comprises a punched metal having a plurality of punched holes.
[0098] In addition, the plate type thin heat pipe of the present invention may comprises a plate type thin heat pipe, wherein another wire member is further arranged in such manner that said another wire member crosses said wire member arranged on one or both of outer surfaces of said unit of punched metal plates of said wick.
[0099] In addition, the plate type thin heat pipe of the present invention may comprises a plate type thin heat pipe, wherein at least one of said upper plate member and said lower plate member have a recessed portion in a central portion, and said upper plate member and said lower plate member are fitted and outer peripheral portions are joined to form said container including said hollow portion.
[0100] In addition, the plate type thin heat pipe of the present invention may comprises a plate type thin heat pipe, wherein said unit of punched metal plates comprises a circular shaped or a polygonal shaped plate, and said wire member is arranged on both of outer surfaces of said unit of punched metal plates.
[0101] Furthermore, the method for manufacturing a plate type thin heat pipe of the present invention comprises steps of:
[0102] (1) preparing metal wire member placed in a same plane in parallel with a prescribed distance spaced out;
[0103] (2) sandwiching said wire member by a copper thin upper plate member and a copper thin lower plate member in such manner that solder is applied on portions of said upper plate member and lower plate member with which said wire member contacts to provisionally fabricate a container;
[0104] (3) applying a heat treatment to thus provisionally fabricated container at a prescribed temperature to form a hermetically sealed container in which said wire member, said upper plate member and said lower plate member are integrated as a one piece member;
[0105] (4) reducing an inner pressure of said container, and filling water as a working fluid.
[0106] Furthermore, further other embodiment of the plate type thin heat pipe of the present invention is described in detail. More specifically, when copper material is selected as the material for the container and the wick which can use water as a working fluid, it is impossible to practically place a copper wire having a diameter up to 0.5 mm&phgr; along the inner surface of the container. Accordingly, in the present invention, a copper thin plate is used as a supporting material to place the above-mentioned wire along the inner surface of the container, and the copper thin plate with the wire wound is received as a wick within the container.
[0107] For example, the wire is wound around a square copper thin plate in such manner that the wire is guided along the front surface of the copper thin plate from one end to the other end which faces each other, and then along the back surface of the copper thin plate, and then along the front surface again, thus the wire is densely wound. In this case, the end of the wire is entangled to a notch or the like formed in the corner of the thin plate and fixed. The plate-shaped wick having the most effective mechanism for circulating the working fluid along a uni-direction can be thus obtained. Thus prepared wick may be received in the container in the same manner as the mesh, and in addition, as shown in FIG. 5, the above-mentioned wick may be pressed by the group of the protruding portions 12 formed on one of the inner surface of the container to the other inner surface of the container.
[0108] The wick can be received in the container having six sides formed by combining the upper plate member, the lower plate member and the side plate members. In case of a very thin heat pipe, the wick can be received in the container formed by combining one flat plate and the other plate with a recessed portion formed in the central portion thereof.
[0109] However, in that case, since the vaporized fluid is not supplied to the wires wound on one of the sides of the thin copper plate, i.e., the vaporized fluid is supplied to the wires wound on the other side of the thin copper plate, there occurs no condensation of the working fluid in the above-mentioned side of the thin copper plate, thus causing to provide dead space. It is required in the plate type heat pipe to make the container thinner, thus the dead space is not preferable in the plate type heat pipe. It is possible to wind wire on one side of the thin copper plate with notches provided at appropriate interval (pitch) in the short ends of the plate, more specifically, the wire is placed along the side surface of the copper plate, and turned around at the notches to return back, thus repeating in such manner as described above to be wound on the single side of the copper plate. In this case, the dead space can be removed.
[0110] In case that the wire is wound on one surface of the thin plate, the thin plate with the wire wound can be used as one of the plate member of the container, thus reducing the numbers of the component of the heat pipe and being preferable.
[0111] Although, the thin plate with the wire wound comprises an ordinary flat plate, a punched metal plate having a plurality of punched holes can be used in stead of the above-mentioned flat plate. In this case, even if the wire is wound on both sides of the punched metal plate, there is no such dead space as in the flat plate. More specifically, the vaporized working fluid condenses on both surfaces of the punched metal plate so that both surfaces of the punched metal plate with the wire wound can function as a circulating passage for the working fluid.
[0112] In addition, in case that the wire is wound along one direction on the surface of thin plate, the function of circulating working fluid is effective in one direction, thus the function of the plate type heat pipe is limited. Accordingly, there is proposed a method for circulating the working fluid in two directions (two dimensions) of a longitudinal direction and a lateral direction in which the first wire is wound between short ends of the punched metal plate, and then the second wire is wound between long ends of the punched metal plate in such manner that the first wire and the second wire cross on the surface of the punched metal plate. Although the above-mentioned structure resembles a mesh at first glance, the practical effect between the above-mentioned structure and a mesh are totally different.
[0113] More specifically, in case of the mesh, the first wire extends along the inner surface of the container and the second wire extends to cross the first wire in such manner that the second wire extends alternatively to the upper side of the first wire and the lower side of the first wire, while the first wire extends alternatively to the upper side of the second wire and the lower side of the second wire. Therefore, the wire does not constantly contact with the inner surface of the container. On the other hand, in the present invention, the wire constantly contact with the inner surface of the container and the portion A shown in FIG. 6 formed between the inner surface of the container and the outer surface of the wire is maintained along the whole length of the wire. In other words, in the present invention, the wick has a structure in which there are two straight passages comprising an upper straight passage and a lower straight passage for the working fluid formed by the wires. The above-mentioned structure is shown in FIG. 7. As shown in FIG. 7, the protruding portions 17 are formed on the inner surface of the upper flat plate 15 having a recessed portion, and the wick comprising the punched metal plate 18 with the X directional wire 19 and the Y directional wire 20 wound is received in the recessed portion and pressed by the protruding portions against the inner surface of the other flat plate 16.
[0114] However, although the above-mentioned type of the wick secures the passage for vaporized fluid in upper side of the container formed by the protruding portions, the vaporized working fluid only condenses there, since there is no circulating structure. The wick structure using mesh as shown in FIG. 5 has the same limitation as described above.
[0115] To improve the above-mentioned structure of the wick, there is proposed another structure of the wick, in which a unit of punched metal plates formed by two punched metal plates with a prescribed vaporized passage provided therebetween is prepared, and then, the wire is wound on the outer surface of the unit of punched metal plates. According to the above-mentioned structure, the space within the container can be effectively used, and the same function can be provided with both surfaces of the punched metal plates.
[0116] As shown in FIG. 8, the protruding portions (not shown) are formed on one of the punched metal plates, and then a unit of punched metal plates are prepared by combining two punched metal plates with a space provided therebetween, and then, the wire 22 is wound in X direction on the respective outer surface of the punched metal plates, and the wire 24 is wound in Y direction on the respective outer surface of the punched metal plates with the wire 22 wound. The thus prepared wick is then received within the container formed by the upper flat plate member 21 and the lower flat plate member 25. In this case, when the container is designed so as to have the inner height, i.e., the distance between the inner surface of the upper plate member and the inner surface of the lower plate member, which is equal to a total of the thickness of the both plate members, the difference between the punched metal plates (i.e., the height of the protruding portion), and 4 times of outer diameter of the wire, the group of outer wires 24 (i.e., Y direction) closely contact with the respective inner surfaces 21, 25 of the container. The group of inner wires 22 (i.e., X direction) closely contact with the respective punched metal plates 23. The space between the two punched metal plates functions as the passage for vaporized fluid, and the vaporized working fluid condenses on the group of wires. Thus, the plate type heat pipe of the present invention has a wick structure in which the straight passages for circulation in both of X direction and Y direction are arranged on both of the upper and lower inner surfaces of the heat pipe so as to secure the passage for vaporized working fluid.
[0117] The first embodiment of the container of the present invention comprises a container of a plate type heat pipe formed by combining a flat plate having a recessed portion in a central portion thereof and a passage connecting to outside in a corner portion of an outer peripheral portion thereof, and another flat plate, then brazing the outer peripheral portion of the flat plate to the another flat plate, and caulking the passage to form a hermetically sealed hollow portion.
[0118] FIG. 9 is a schematic perspective view showing a portion to be sealed in the container of the invention. FIG. 10 is a plan view showing a lower plate member including a portion to be sealed shown in FIG. 9.
[0119] As shown in FIG. 9, a square copper plate is press-worked to form a central portion 32 recessed from the square outer peripheral portion 31. The corner portion 33 which is a part of the outer peripheral portion is positioned on the same plane to the recessed central portion.
[0120] Solder is applied on the outer peripheral portion 31, and then the other flat copper plate and the copper plate with the recessed portion formed are combined and adhered each other to form the container having the opening portion in the corner portion 33.
[0121] Working fluid is injected from the corner portion 33, and then the container is heated to remove gas within the container. The corner portion 33 is obliquely caulked, and then welded to prepare the plate type heat pipe of the present invention.
[0122] The tip portion of the corner portion 33 may be received in the vacuum system including a soft packing on the opening portion thereof, and introducing the vapor into the container, and then removing gas under reduced pressure to form the plate type heat pipe.
[0123] According to the present invention, the plate type heat pipe having, for example, a thickness of the container: 1 mm, a thickness of the plate member: 0.2 mm, and inner height of the container (the distance between the upper inner surface of the plate member and the lower inner surface of the plate member): 0.6 mm can be fully prepared.
[0124] In addition, the protruding portions having the same height as the inner height of the container are formed on the inner surface of one of the plate member in a prescribed interval, and solder is applied on the tip portion of the protruding portions, the plate type heat pipe can be prepared. According to the above, the strength of the thin heat pipe is reinforced. For example, when the protruding portions are arranged in a regular square form with 10 mm pitch, the heat pipe can be prevented from being deformed, even under the inner pressure of 1 kg/cm2.
[0125] The press-worked copper is the most effective material for the container shown in FIG. 9. Aluminum is excellent in workability, however, water cannot be used with aluminum container. In the present invention, copper can be effectively used for the material of the container, thus remarkably effective in property.
[0126] Furthermore, the plate type thin heat pipe of the present invention comprises: (1) a group of wire members comprising a plurality of first metal wire members placed in a same plane in parallel with a prescribed distance spaced out, and a plurality of second metal wire members placed in a same plane in parallel with a prescribed distance spaced out and placed so as to cross said plurality of first metal wire members; (2) a container having a hollow portion formed by an upper plate member made of thin copper plate, in a central portion of which a recessed portion is formed to receive said group of wire members and in a corner portion of which a passage connecting said recessed portion to outside is formed, and a flat lower pate member made of thin copper plate, outer peripheral portion of which are joined and said passage is caulked so as to be hermetically sealed and inner pressure thereof is reduced, said group of wire members being received in said hollow portion and each of inner surface of said upper plate member and said lower plate member contacting said group of wire members; (3) water as a working fluid received in said container.
[0127] In addition, the plate type thin heat pipe of the present invention may comprises: (1) a container having a hollow portion formed by an upper plate member made of thin copper plate, in a central portion of which a recessed portion is formed and in a corner portion of which a passage connecting said recessed portion to outside is formed, and a flat lower pate member made of thin copper plate, outer peripheral portion of which are joined and said passage is caulked so as to be hermetically sealed and inner pressure thereof is reduced; (2) a wick comprising a flat plate member and a wire member wound around said flat plate member, received in said container; (3) a working fluid received in said container.
[0128] In addition, the plate type thin heat pipe of the present invention may comprises: (1) a container having a hollow portion formed by an upper plate member made of thin copper plate, in a central portion of which a recessed portion is formed and in a corner portion of which a passage connecting said recessed portion to outside is formed, and a flat lower pate member made of thin copper plate, a plurality of protruding portions being formed on an inner surface of said upper plate member or said lower plate member, outer peripheral portions of which are joined and said passage is caulked so as to be hermetically sealed and inner pressure thereof is reduced; (2) a wick comprising a flat plate member and a wire member wound around said flat plate member, received in said container in such a manner that said wick is pressed by said plurality of protruding portions to an opposing inner surface of said container; and (3) a working fluid received in said container.
[0129] In addition, the plate type thin heat pipe of the present invention may comprises: (1) a container having a hollow portion formed by an upper plate member made of thin copper plate, in a central portion of which a recessed portion is formed and in a corner portion of which a passage connecting said recessed portion to outside is formed, and a flat lower pate member made of thin copper plate, outer peripheral portions of which are joined and said passage is caulked so as to be hermetically sealed and inner pressure thereof is reduced; (2) a wick comprising a unit of punched metal plates formed by combining two punched metal plates in which at least one of said punched metal plates have a plurality of protruding portions, and said two punched metal plates are placed face to face with a distance corresponding to a height of said protruding portion and a wire member wound around said unit of punched metal plates; (3) a working fluid received in said container.
[0130] In the above-mentioned embodiment of the plate type thin heat pipe of the present invention, the passage formed in the corner can be sealed only by caulking the corner portion. In addition, since any protruding portion is not formed near the portion to be sealed and the portion to be sealed is formed in the corner portion, gas is hardly remained when removing gas in the container.
[0131] In addition, in the plate type thin heat pipe of the present invention, another wire member is further arranged in such manner that the another wire member crosses the wire member arranged on both of outer surfaces of the unit of punched metal plates of the wick.
[0132] In addition, in the plate type thin heat pipe of the present invention, the above-mentioned upper plate member may be integrally formed as a one piece member by press-working.
[0133] As described above, according to the container of the present invention, gas can be easily removed by a boiling method. In particular, gas is hardly remained. In addition, since the corner portion is only caulked, the container is easily manufactured at low cost.
EXAMPLE Example 1[0134] According to the present invention, a container of a plate type heat pipe of the present invention is formed by using two copper plate having a thickness of 0.2 mm, a width of 20 mm and length 50 mm, ten pieces of copper wire of a diameter of 0.2 mm&phgr; and length of 50 mm, and 4 sheets of #200 screen meshes, as follows:
[0135] 10 pieces of the copper wires are placed in parallel each other with 2 mm pitch on one of the copper plate, and then 4 sheets of the meshes are interposed between the disposed wires and the other copper plate. Solder is applied in advance to the side portions of the copper wire to contact with the copper plate and the mesh, and each end of the meshes. A square bar is placed on each end of the copper plate so as to seal the container.
[0136] Then, thus formed copper plates with the copper wire and meshes placed and pinched by a fixing fig are introduced into a furnace as they are.
[0137] In addition, a small copper tube is interposed in advance so as to extrude from the inside of the container to outside, and then the air within the container is removed and a working fluid is injected into the container by the use of the tube. Thus, a plate type thin heat pipe of the present invention having a width of 20 mm, a length of 50 mm, and a thickness of 1 mm is formed. When a chip generating heat was cooled by thus formed plate type thin heat pipe of the present invention, the chip was effectively cooled.
Example 2[0138] The same material as in Example 1 except the following material are used and a plate type heat pipe of the present invention is formed in the same manner as in Example 1 except the following. More specifically, 4 sheets of the meshes are divided into respective 2 sheets. The group of copper wires placed in parallel are interposed between a set of 2 sheets of meshes, and then, thus formed copper wires and meshes are interposed by two copper plates to form a plate type thin heat pipe of the present invention having a width of 20 mm, a length of 50 mm, and a thickness of 1 mm. When a chip generating heat was cooled by thus formed plate type thin heat pipe of the present invention, the chip was effectively cooled.
Example 3[0139] According to the present invention, the plate type heat pipe of the present invention schematically shown in FIG. 3 is formed by using two copper plate having a thickness of 0.2 mm, a width of 40 mm and a length 60 mm, 36 pieces of copper wire of a diameter of 0.3 mm&phgr; and length of 60 mm, and 56 pieces of copper wire of a diameter of 0.3 mm&phgr; and length of 40 mm, as follows:
[0140] Copper wires 5 are placed in parallel each other with 1 mm pitch on one of the copper plate 4. Solder is applied in advance to the side portions of the copper wire to contact with the copper plate. Copper wires are bundled before being cut to be the above mentioned size, and applied tensile force, and then pressed and adhered to the end portions of the copper placed below, thus forming a unit. In the same manner, another unit in which copper wires 5 are placed on the copper plate 5 is formed.
[0141] The above-mentioned two units are placed face to face in such manner the axis directions of the copper wires are perpendicular to each other, and a square bar is placed on each end of the copper plate, and then the container is brazed in the same manner as in Example to integrally form as a one piece member.
[0142] In addition, a small copper tube is interposed in advance so as to extrude from the inside of the container to outside, and then the air within the container is removed and a working fluid is injected into the container by the use of the tube. Thus, a plate type thin heat pipe of the present invention having a width of 40 mm, a length of 60 mm, and a thickness of 1 mm is formed. When a chip generating heat was cooled by thus formed plate type thin heat pipe of the present invention, the chip was effectively cooled.
Example 4[0143] According to the present invention, a recessed portion having a depth of 0.8 mm is formed in the center portion of a square copper plate having a thickness of 0.2 mm, a width of 25 mm and a length 50 mm in such manner that a peripheral portion having a width of 2 mm in the copper plate is remained intact, i.e., being flat. Then, on one of the corners of the square copper plate, a passage portion to be connected outside is formed. The passage has a width of 1 mm and the same height of the recessed portion (i.e., 0.8 mm). An angle formed by the passage and the end of the copper plate is 45 degrees. The above-mentioned plate was formed by press-working.
[0144] In addition, cylindrical protruding portions having a height of 0.4 mm and a diameter of 1 mm&phgr; are formed in a square pattern with 3 mm pitch on other copper plate having the same size as the copper plate with the protruding portions formed. The above-mentioned plate was formed by press-working.
[0145] Four sheets of meshes (#120) having a width of 20 mm and a length of 45 mm are prepared as a wick, and placed in the recessed portion in the above-mentioned copper plate. Solder is applied to the outer peripheral portion having width of 2 mm of the above-mentioned copper plate, and then the other copper plate with the protruding portions formed are placed face to face on the above-mentioned copper plate. Thus formed container is fix by a clip, and is introduced into a furnace to integrally form a one piece member.
[0146] Water is injected by a injector through the opening portion of the passage portion having a height of 0.8 mm and width of 1 mm, and then the container is heated so as for the water to be boiled. Thus, a plate type thin heat pipe of the present invention having a width of 25 mm, a length of 50 mm, and a thickness of 1.2 mm is formed. When a chip generating heat was cooled by thus formed plate type thin heat pipe of the present invention, the chip was effectively cooled.
Example 5[0147] According to the present invention, a recessed portion having a depth of 1 mm is formed in the center portion of a square copper plate having a thickness of 0.2 mm, a width of 50 mm and a length 100 mm in such manner that a peripheral portion having a width of 2 mm in the copper plate is remained intact, i.e., being flat. Then, cylindrical protruding portions having a height of 1 mm and a diameter of 3 mm&phgr; are formed in a square pattern with 10 mm pitch on the center portion of the copper plate. The above-mentioned plate was formed by press-working.
[0148] In addition, cylindrical protruding portions having a height of 0.5 mm and a diameter of 3 mm&phgr; are formed in a square pattern with 5 mm pitch on other copper plate having the same size as the copper plate. The above-mentioned plate was formed by press-working.
[0149] Six sheets of meshes (#200) having a width of 45 mm and a length of 95 mm are prepared as a wick, and layered. The corresponding holes to the above-mentioned cylindrical protruding portions, having a diameter of 3 mm&phgr; are formed in a square pattern with 10 mm pitch on the meshes. Thus formed meshes are placed in the recessed portion in such manner that the cylindrical protruding portions are inserted in the corresponding holes.
[0150] Solder is applied to the outer peripheral portion having width of 2 mm of the above-mentioned copper plate and the tip ends of the cylindrical protruding portions, and then the other copper plate are placed face to face on the above-mentioned copper plate. Thus formed container is fix by a clip, and is introduced into a furnace to integrally form a one piece member.
[0151] Water is injected by a injector through an opening portion of a passage portion having a height of 1 mm and width of 1 mm, and then the container is heated so as for the water to be boiled. Thus, a plate type thin heat pipe of the present invention having a width of 50 mm, a length of 100 mm, and a thickness of 1.4 mm is formed. When a chip generating heat was cooled by thus formed plate type thin heat pipe of the present invention, the chip was effectively cooled.
Example 6[0152] According to the present invention, on the square portion of 21 mm×66 mm in the square copper plate having a thickness of 0.2 mm, a width of 25 mm and a length of 70 mm except a peripheral portion having a width of 2 mm, dimples having a height of 0.8 mm and a diameter of 0.2 mm&phgr; are arranged along the two short ends having a length of 21 mm of the above-mentioned square portion of the copper plate with 0.5 mm pitch. The total of the dimples on the short end was 40. The copper wire having a diameter of 0.2 mm&phgr; are wound on one side of the copper plate using the dimples as a turn-around point. Both ends of the copper wire are fixed to the far end dimples, respectively.
[0153] In addition, a recessed portion having a depth of 0.6 mm is formed in the center portion of a square copper plate having a thickness of 0.2 mm, a width of 25 mm and a length 70 mm in such manner that a peripheral portion having a width of 2 mm in the copper plate is remained intact, i.e., being flat. Then, on one of the corners of the square copper plate, a passage portion to be connected outside is formed. The passage has a width of 1 mm and the same height of the recessed portion (i.e., 0.6 mm). An angle formed by the passage and the end of the copper plate is 45 degrees. The above-mentioned plate was formed by press-working.
[0154] Solder is applied to the outer peripheral portion having width of 2 mm of the above-mentioned copper plate, and then the other copper plate with the dimples formed are placed face to face on the above-mentioned copper plate. Thus formed container is fix by a clip, and is introduced into a furnace to integrally form a one piece member.
[0155] Water is injected by a injector through the opening portion of the passage portion having a height of 0.6 mm and width of 1 mm, and then the container is heated so as for the water to be boiled. Thus, a plate type thin heat pipe of the present invention having a width of 25 mm, a length of 70 mm, and a thickness of 1.0 mm is formed. When a chip generating heat was cooled by thus formed plate type thin heat pipe of the present invention, the chip was effectively cooled.
Example 7[0156] Copper wire having a diameter of 0.2 mm&phgr; is wound on a punched copper plate having a thickness of 0.2 mm, a width of 20 mm and a length of 65 mm, the punched holes of which are formed in a square pattern with 2 mm pitch, each being a size of 1 mm&phgr;. The wire is wound on both sides of the punched copper plate in such manner that it is wound 38 times between two short ends having length of 20 mm respectively with 0.5 mm pitch from the front side surface to the back side surface, and the front side surface again, thus repeated. Both ends of the copper wire are fixed to the far end punched holes, respectively.
[0157] In addition, a recessed portion having a depth of 1.0 mm is formed in the center portion of a square copper plate having a thickness of 0.2 mm, a width of 25 mm and a length 70 mm in such manner that a peripheral portion having a width of 2 mm in the copper plate is remained intact, i.e., being flat. Then, on one of the corners of the square copper plate, a passage portion to be connected outside is formed. The passage has a width of 1 mm and the same height of the recessed portion (i.e., 1.0 mm). An angle formed by the passage and the end of the copper plate is 45 degrees. The above-mentioned plate was formed by press-working. Furthermore, other copper plate having the same size as the above-mentioned copper plate is prepared. On the other copper plate, protruding portions having a height of 4 mm, and a diameter of 1 mm&phgr; are formed in a square pattern with 3 mm pitch. The above-mentioned other plate was formed by press-working.
[0158] The punched copper plate with wire wound as a wick is received in the recessed portion of the copper plate. Then, solder is applied to the outer peripheral portion having width of 2 mm of the above-mentioned copper plate, and then, the other copper plate with the protruding portions formed are placed face to face on the above-mentioned copper plate. Thus formed container is fix by a clip, and is introduced into a furnace to integrally form a one piece member.
[0159] Water is injected by a injector through the opening portion of the passage portion having a height of 1 mm and width of 1 mm, and then the container is heated so as for the water to be boiled. Thus, a plate type thin heat pipe of the present invention having a width of 25 mm, a length of 70 mm, and a thickness of 1.4 mm is formed. When a chip generating heat was cooled by thus formed plate type thin heat pipe of the present invention, the chip was effectively cooled.
Example 8[0160] A punched copper plate A is prepared which has a thickness of 0.1 mm, a width of 20 mm and a length of 65 mm, the punched holes of which are formed in a square pattern with 2 mm pitch, each being a size of 1 mm&phgr;. Then, other punched copper plate B is prepared which has a thickness of 0.1 mm, a width of 20 mm and a length of 65 mm, the punched holes of which are formed in a square pattern with 2 mm pitch, each being a size of 1 mm&phgr;, and furthermore, cylindrical dimples having a height of 0.2 mm and a diameter of 1 mm&phgr;, with 10 mm pitch are formed. Thus prepared copper plates A and B are placed face to face with the dimples positioned therebetween, thus forming a unit of punched metal plates.
[0161] The copper wire having a diameter of 0.2 mm&phgr; is wound on both sides of the unit of the punched metal plates in such manner that it is wound 65 times between two long ends having length of 65 mm respectively with 1 mm pitch from the front side surface to the back side surface, and the front side surface again, thus repeated. Furthermore, the copper wire is wound on both sides of the unit of the punched metal plates with the wire wound as described above, in such manner that it is wound 38 times between two short ends having length of 20 mm respectively with 0.5 mm pitch from the front side surface to the back side surface, and the front side surface again, thus repeated. The Both ends of the copper wire are fixed to the far end punched holes, respectively.
[0162] In addition, a recessed portion having a depth of 1.2 mm is formed in the center portion of a square copper plate having a thickness of 0.2 mm, a width of 25 mm and a length 70 mm in such manner that a peripheral portion having a width of 2 mm in the copper plate is remained intact, i.e., being flat. Then, on one of the corners of the square copper plate, a passage portion to be connected outside is formed. The passage has a width of 1 mm and the same height of the recessed portion (i.e., 1.2 mm). An angle formed by the passage and the end of the copper plate is 45 degrees. The above-mentioned plate was formed by press-working. Furthermore, other plat copper plate having the same size as the above-mentioned copper plate is prepared. The above-mentioned other plate was formed by press-working.
[0163] The unit of the punched copper plates with the copper wire wound as a wick is received in the recessed portion of the copper plate. Then, solder is applied to the outer peripheral portion having width of 2 mm of the above-mentioned copper plate, and then, the other flat copper plate are placed face to face on the above-mentioned copper plate. Thus formed container is fix by a clip, and is introduced into a furnace to integrally form a one piece member.
[0164] Water is injected by a injector through the opening portion of the passage portion having a height of 1.2 mm and width of 1 mm, and then the container is heated so as for the water to be boiled. Thus, a plate type thin heat pipe of the present invention having a width of 25 mm, a length of 70 mm, and a thickness of 1.6 mm is formed. When a chip generating heat was cooled by thus formed plate type thin heat pipe of the present invention, the chip was effectively cooled.
Example 9[0165] According to the present invention, a recessed portion having a depth of 0.6 mm is formed in the center portion of a square copper plate having a thickness of 0.2 mm, a width of 25 mm and a length 50 mm in such manner that a peripheral portion having a width of 2 mm in the copper plate is remained intact, i.e., being flat. Then, on one of the corners of the square copper plate, a passage portion to be connected outside is formed. The passage has a width of 1 mm and the same height of the recessed portion (i.e., 0.6 mm). An angle formed by the passage and the end of the copper plate is 45 degrees. The above-mentioned plate was formed by press-working.
[0166] In addition, cylindrical protruding portions having a height of 0.6 mm and a diameter of 3 mm&phgr; are formed in a square pattern with 10 mm pitch on other copper plate having the same size as the copper plate with the recessed portion formed. The above-mentioned plate was formed by press-working.
[0167] Four sheets of meshes (#120) having a width of 20 mm and a length of 45 mm are prepared as a wick, and layered. The corresponding holes to the above-mentioned cylindrical protruding portions, having a diameter of 3 mm(pare formed in a square pattern with 10 mm pitch on the meshes. Thus formed meshes are placed in the recessed portion in such manner that the cylindrical protruding portions are inserted in the corresponding holes.
[0168] Solder is applied to the outer peripheral portion having width of 2 mm of the above-mentioned copper plate and the tip ends of the cylindrical protruding portions, and then the other copper plate are placed face to face on the above-mentioned copper plate. Thus formed container is fix by a clip, and is introduced into a furnace to integrally form a one piece member.
[0169] Water is injected by a injector through an opening portion of a passage portion having a height of 0.6 mm and width of 1 mm, and then the container is heated so as for the water to be boiled. Thus, a plate type thin heat pipe of the present invention having a width of 25 mm, a length of 50 mm, and a thickness of 1 mm is formed. When a chip generating heat was cooled by thus formed plate type thin heat pipe of the present invention, the chip was effectively cooled.
[0170] According to the present invention, it is possible to fabricate the plate type heat pipe made of copper which is substantially a multiple through holes type of heat pipe with the use of water as a working fluid.
[0171] Furthermore, in the present invention, mesh is fixed to the inner surface of the container, thus the passage for a vaporized working fluid can be stably secured. In addition, it is possible to provide a wick structure by the use of wire without using mesh. Furthermore, it is possible to provide a large amount of the above-mentioned heat pipe and the wick.
[0172] Furthermore, according to the present invention, in comparison with the conventional heat pipe in which mesh is simply received within the container, since the mesh surly and firmly contact with the inner surface of the container, the passage for vaporized working fluid is secured so as to remarkably increase the amount of the transferred heat.
[0173] In addition, it is possible to obtain the plate type thin heat pipe without deformation by the inner pressure thereof. In addition, it is possible to surely fix the wire to the inner surface of the container in the plate type heat pipe. Furthermore, it is possible to provide a plate type thin heat pipe in which the working fluid can circulate in X direction and Y direction in the same manner as in the mesh without losing an excellent property of the wire as a wick.
[0174] Furthermore, according to the present invention, it is possible to provide a plate type heat pipe which can secure the passage for a vaporized working fluid, and includes an excellent wick structure on both of the upper inner surface and the lower inner surface of the container.
[0175] In addition, according to the present invention, it is possible to provide the plate type heat pipe which has a portion to be simply and easily sealed. In particular, it is possible to provide a portion to be effectively sealed even in the plate type thin heat pipe having a total thickness of up to 1.5 mm.
Claims
1. A heat transfer apparatus comprising a wick, wherein said wick comprises:
- a flat plate member comprising a unit of punched metal plates formed by combining two punched metal plates in which at least one of said punched metal plates have a plurality of protruding portions, and said two punched metal plates are placed face to face with a distance corresponding to a height of said protruding portion; and
- a wire member wound around said flat plate member, said wick being received within a container having a hollow portion of a sealed plate type thin heat pipe.
2. A plate type thin heat pipe comprising:
- a container having a hollow portion which is reduced in inner pressure and hermetically sealed, formed by an upper plate member comprising a thin copper plate and a lower plate member comprising a thin copper plate;
- a wick comprising a substantially planar array of wires received in said container; and
- a working fluid received in said container.
3. The plate type thin heat pipe of claim 2 wherein said wick comprises a flat plate member and a wire member wound around said flat plate member.
4. The plate type thin heat pipe of claim 2 wherein said wick is formed by being arranged on an inner surface of one of said upper plate member and said lower plate member.
5. The plate type thin heat pipe of claim 4 wherein said wick is received in said container in such a manner that said wick is pressed by a plurality of protruding portions formed in one inner surface of said container to an opposing inner surface of said container.
6. A plate type thin heat pipe comprising:
- a container having a hollow portion formed by an upper plate member made of thin copper plate, in a central portion of which a recessed portion is formed and in a corner portion of which a passage connecting said recessed portion to outside is formed, and a flat lower pate member made of thin copper plate, outer peripheral portion of which are joined and said passage is caulked so as to be hermetically sealed and inner pressure thereof is reduced;
- a wick received in said container;
- a working fluid received in said container.
7. The plate type thin heat pipe of claim 6 wherein the wick comprises a flat plate member and a wire member wound around said flat plate member.
8. A method of making a heat pipe comprising:
- forming first and second metal plates, said first plate being formed with a recessed portion in a central portion thereof and a passage formed in a corner portion of an outer peripheral portion thereof,
- brazing said outer peripheral portion of said first flat plate to said second flat plate; and
- caulking said passage to form a hermetically sealed hollow portion.
9. The method as claimed in claim 8, wherein said second plate is formed with a recessed portion in a central portion thereof and a passage formed in a corner portion of an outer peripheral portion thereof.
10. A heat transfer apparatus comprising:
- a first plate member comprising a recessed portion and a plurality of protruding portions extending from said recessed portion;
- a second plate member; and
- a flat mesh member disposed on said second plate member, wherein said first and second plate members are connected so that said recessed portion forms a cavity and said protruding portions abut said flat mesh material.
11. The apparatus of claim 10, wherein said flat mesh material comprises a plurality of metal wires configured in a grid pattern.
12. The apparatus of claim 10, further comprising a plurality of flat mesh members stacked on said second plate member.
13. The apparatus of claim 10, wherein said protruding portions are integrally formed on said first plate member.
14. A heat transfer apparatus comprising:
- a first plate member comprising a recessed portion and a plurality of protruding portions extending from said recessed portion;
- a second plate member;
- a plurality of wire members disposed on said second plate member; and
- a flat mesh member disposed on said plurality of wire members, wherein said first and second plate members are connected so that said recessed portion forms a cavity and said protruding portions abut said flat mesh material.
15. The apparatus of claim 14, wherein said plurality of wire members are aligned in parallel.
16. The apparatus of claim 14, wherein said plurality of wire members comprises a first plurality of wire members that are aligned in parallel and a second plurality of wire members that are aligned in parallel, wherein said first plurality of wire members is disposed next to said second plurality of wire members so that each of said first plurality of wire members are perpendicular to each of said second plurality of wire members.
17. A heat transfer apparatus comprising:
- a first plate member comprising a recessed portion and a plurality of protruding portions extending from said recessed portion;
- a second plate member; and
- a wick comprising a flat plate member and a wire member wound around said flat plate member, said wick being disposed on said second plate member, wherein said first and second plate members are connected so that said recessed portion forms a cavity and said protruding portions abut said flat mesh material.
18. A method of manufacturing a heat transfer apparatus comprising:
- providing a first plate member comprising a recessed portion and a plurality of protruding portions extending from said recessed portion;
- providing a second plate member;
- placing a plurality of wire members on said second plate member;
- placing a flat mesh member on said plurality of wire members; and
- connecting said first and second plate members so that said recessed portion forms a cavity and said protruding portions abut said flat mesh material.
19. The method of claim 18, further comprising providing a fluid between said first and second plate members.
Type: Application
Filed: Jun 28, 2002
Publication Date: Jan 22, 2004
Inventors: Hajime Noda (Tokyo), Kenya Kawabata (Tokyo), Toshiaki Nakamura (Tokyo), Jun Niekawa (Tokyo)
Application Number: 10187133
International Classification: F28D015/00;
