Patent Publication Number: US-2005126750-A1

Title: Flow-path constituting body

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
      This application claims priority to Japanese Application No. 2003-387663 filed Nov. 18, 2003, which is incorporated herein by reference.  
     FIELD OF THE INVENTION  
      The present invention relates to a flow-path constituting body and specifically relates to a construction of a flow-path constituting body that is suitable to cool the heating part of an electronic apparatus such as a personal computer.  
     BACKGROUND OF THE INVENTION  
      In recent years, the performance of a personal computer has been significantly improved and the processing speed of a CPU (Central Processing Unit) has been also rapidly improved. Therefore, the heat generating amount generated from a CPU chip and the like increases and thus an improved cooling method is required. A conventional cooling method is performed such that the heating part such as the CPU chip is fixed on a heat sink provided with fins and air-cooling is forcibly performed by sending airflow to the heat sink with a fan or the like. However, in the air-cooling system described above, noise of an air-cooling fan increases as cooling performance is enhanced. Further, since a ventilation space for cooling is not sufficiently ensured in a housing of a miniaturized computer, a sufficient cooling efficiency can not be obtained.  
      A liquid cooling system is known in which a cooling jacket is contacted on a heating part such as a CPU chip, and a pump for supplying liquid in the cooling jacket to circulate the liquid in a liquid circulation path and a heat radiation part having a radiator structure are provided (see Japanese Patent Laid-Open No. 2002-99356).  
      However, in the cooling system of the conventional liquid cooling system, for example, the cooling jacket, the heat radiation part, the pump, a reserve tank and the like are connected with a tube made of metal or synthetic resin. Therefore, a lot of tubes and connection couplings are required, which causes to increase the number of component parts and to complicate connecting operations at the time of assembling and thus time and labor are imposed for manufacturing.  
      Further, since a tube made of synthetic resin having flexibility is not generally provided with a gas barrier property, a coolant cannot be completely prevented from volatilizing outside at the tubes or connecting portions between the tubes and respective components. Therefore, the amount of the coolant may decrease according to the lapse of time. Accordingly, a secondary chamber such as the reserve tank is required to be provided while the volatilization amount of the coolant and the degree of expansion/shrinkage of the coolant are taken into consideration and moreover a sufficient capacity is required and thus it is difficult to miniaturize the system. Alternatively, it is conceivable that a metal pipe is used to prevent from volatilization of the coolant. However, in this case, the pipe is difficult to be bent in an appropriate shape and thus the laying work and the aligning work of piping become difficult.  
     OBJECT AND SUMMARY OF THE INVENTION  
      In view of the problems described above, it is a primary object and advantage of the present invention to provide a flow-path constituting body, in which the laying work and the aligning work are easy due to its flexibility when the flow path of a fluid is constructed, and is capable of extremely easily performing the constructing work for a flow path in manufacturing. Also, it is a secondary object and advantage of the present invention to provide a flow-path constituting body which is capable of absorbing its volume variation due to the temperature variation of a fluid (liquid) while providing a sufficient flexibility, and is capable of ensuring the sealing property of the fluid.  
      In order to achieve the above object and advantage, according to an embodiment of the present invention, there is provided a flow-path constituting body including at least two port parts where a fluid flows in or flows out, a flow path which is in communication between the port parts, and a flexible film for forming the flow path. The flow path is constructed by using a non-bonded area defined by a bonded area of the flexible film.  
      In accordance with the embodiment of the present invention, the flow path is constructed of substantially only the flexible film. Therefore, its manufacturing is easy, the flexibility of the flow-path constituting body can be enhanced, and the sealing property of the flow path can be also enhanced.  
      Also, another flow-path constituting body in accordance with an embodiment of the present invention includes at least two port parts where a fluid flows in or flows out and a flow path which is in communication between the port parts, and at least a part of the flow path is constructed by a non-bonded area defined by a bonded area of a flexible film or a flexible film and another member.  
      At least a part of the flow path is constructed of the non-bonded area defined by the bonded area. In this case, the flow-path constituting body may be constructed such that flexible films not less than two sheets are adhesively bonded partly to one another, one piece of flexible film is bent and folded to be adhesively bonded partly, or a flexible film and another member are adhesively bonded partly.  
      According to the embodiment having the construction described above, the flow path is formed so as to be in communication between the port parts and at least a part of the flow path is constructed by a non-bonded area defined by a bonded area of a flexible film or a flexible film and another member. Therefore, the flow path in an appropriate configuration and construction can be extremely easily constructed. Especially, when the flow path is constructed by the non-bonded area defined by the bonded area formed of two flexible film portions, a sufficient flexibility can be ensured and thus the laying work and the aligning work can be easily performed. Also, since the bonded area is formed by using two flexible film portions or by using a flexible film and another member, the rigidity of the bonded area can be enhanced to some extent. Therefore, since an appropriate maintenance of the flow path configuration is enabled by constructing the configuration of the flow path so as to be adapted in the system beforehand, the constructing work of the flow path can be easily performed. In addition, the flow path configuration can be extremely easily and freely formed by only appropriately designing the bonded area and the non-bonded area formed of the flexible film portions or the flexible film and the another member.  
      In the flow-path constituting body in accordance with the embodiment of the present invention, two pieces of flexible films may be adhesively bonded and integrated partly with each other and the flow path is constructed by the non-bonded area, both sides of which are enclosed and defined by the bonded area. Alternatively, after one piece of flexible film is folded and overlapped, two overlapped flexible films are adhesively bonded partly to keep the folded state. Then the flow path may be constructed by the non-bonded area, both sides of which are enclosed and defined by the bonded area, or by the non-bonded area, both sides of which are enclosed and defined by the bent portion and the bonded area. The another member described above which is adhesively bonded partly to the flexible film may use an arbitrary member, for example, a plate member or a block member made of synthetic resin, metal or the like or may utilize respective construction components such as a heat receiving part or a heat radiation part described later, a frame or a housing.  
      In the present invention, the meaning of “adhesion” is not limited to the case of being adhesively bonded with an adhesive but broadly includes the case when flexible films are adhesively fixed. Especially, it is preferable that two flexible films are directly welded or fused each other, or that a flexible film and another member are directly welded or fused each other.  
      In an embodiment of the present invention, it is preferable that the flow path is constructed so as to be integrally provided with a plurality of flow paths or a branching flow path by using the flexible film. When a plurality of flow paths are integrally constructed by using the flexible film, a plurality of pipes are not required to be connected separately, or a plurality of pipes are not required to be bundled. Therefore, a plurality of flow paths can be collectively disposed without requiring a special work. Further, when the flow path having a branch is integrally constructed by using the flexible film, the complicated pipe connecting work and coupling components are not required. Therefore, the manufacturing cost and the size of piping system can be reduced.  
      In an embodiment of the present invention, it is preferable that the flexible film is a laminated film constructed of a metal layer and a resin layer. When the flexible film is a laminated film constructed of a metal layer and a resin layer, a sufficient flexibility can be ensured while enhancing its fluid sealing property and gas barrier property (steam barrier property). The metal layer of the laminated film may be made of, for example, aluminum, aluminum alloy, silver, silver alloy, copper, copper alloy, gold, gold alloy or the like and may be formed with a foil or an adhesion layer such as a vapor deposition layer or a coating layer. The gas barrier property is easily ensured by providing the metal layer. The resin layer of the laminated film may be preferably made of plastic of polyolefin system such as polyethylene or polypropylene. The laminated film is preferably constructed such that the both faces of the metal layer are respectively covered with the resin layer. Further, each blank material is preferably used with which two resin layers or a resin layer and a metal layer can be welded (fused) to each other. The resin having such heat sealing property is, for example, the above-mentioned polyolefin resin, some of polyesters or nylons.  
      In accordance with an embodiment of the present invention, it is preferable that a stagnation part comprising of a closed non-bonded area is provided on the side of the flow path and is in communication with the flow path. According to the construction described above, since the closed non-bonded area is provided on the side of the flow path, a part of the fluid can be evacuated and thus the volume variation due to the fluid expansion or shrinkage can be absorbed and the bursting of or the fluid leakage from the flow-path constituting body can be prevented. Further, when the flow-path constituting body is installed in an attitude such that the closed non-bonded area is disposed on the upper side of the flow path and liquid is flowed in the flow path, gas contained in the liquid or gas generated from the liquid can be stored in the closed non-bonded area and kept in the state in which the gas is separated from the liquid in the flow path. Therefore, the occurrence of malfunctions due to the gas, for example, the reduction of heat exchange efficiency or the situation that gas enters into a pump to cause to be unable to eject the liquid can be prevented.  
      In accordance with an embodiment of the present invention, it is preferable that a deformation member is accommodated in the closed non-bonded area, whose volume is reduced by compressive deformation. According to the construction described above, since the deformation member is accommodated in the closed non-bonded area, the fluid flowing through the flow path hardly enters into the closed non-bonded area normally so that the fluid does not stagnate. On the other hand, when the volume of the fluid increases, since the deformation member is compressed to reduce its volume, the fluid can enter into the closed non-bonded area only by the reduced amount of the volume. Accordingly, the volume variation of the fluid can be absorbed without almost changing the appearance of the flow-path constituting body.  
      In accordance with an embodiment of the present invention, it is preferable that a cross-section holding means for maintaining the flowing cross-section of the flow path is provided. Since the flow path in the present invention is constructed with the non-bonded area of the flexible film, it is conceivable that the flowing cross-section of the flow path is not sufficiently ensured when the fluid pressure is small. According to the embodiment of the present invention, since the flowing cross-section can be sufficiently ensured by providing the cross-section holding means for maintaining the flowing cross-section of the flow path, the flow path for the fluid can be sufficiently ensured and the flowing resistance can be reduced. The cross-section holding means may be a member which ensures a space between the flexible film portions in the non-bonded area or a space between the flexible film and the another member in the non-bonded area. For example, an inner support member disposed within the flow path is used as the cross-section holding means, which acts to separate the flexible film portions from each other or to separate the flexible film from the another member. Alternatively, an outside support member is used as the cross-section holding means, which is fixed on the outer face of one of the flexible film portions or of the flexible film in the non-bonded area so as to act to separate from the other flexible film portion or the another member. Especially, the inner support member disposed within the flow path is preferable because it can further surely maintain the cross section of the flow path. Since the inner support member is disposed within the flow path, it is preferably constructed so as not to obstruct the flow of the fluid. For example, the inner support member is preferably a hollow member. Also, the cross-section holding means is preferably constructed so as not to obstruct the flexibility of the flow-path constituting body in the flow path direction. Concretely, the cross-section holding means also preferably has a flexibility capable of bending in the flow direction. For example, when a hollow member is used as the inner support member, the hollow member may be constructed of flexible blank material or in a spiral shape.  
      A heat exchanging system and a temperature control system can be constructed by using the flow-path constituting body described above. For example, the heat exchange (temperature control) system includes a heat receiving part having a heat absorption function, a heat radiation part having a heat radiation function, a circulation path passing through the heat receiving part and the heat radiation part, and a fluid propulsion means for propelling fluid circulating in the circulation path. In the heat exchange (temperature control) system, at least a part of the circulation path is constructed by using either of the flow-path constituting bodies described in the above-mentioned embodiments of the present invention. The flow-path constituting body may connect, for example, such that flow path is constructed between the heat receiving part and the heat radiation part, between the heat radiation part and the fluid propulsion means, or between the heat receiving part and the fluid propulsion means. In this case, two flow paths of a forward path and a return path provided between respective construction components are preferably constructed in an integral flow-path constituting body. Also, all of the connecting flow paths between the respective construction components provided in the system are further preferably constructed with a single integral flow-path constituting body.  
      Other features and advantages of the invention will be apparent from the following detailed description, taken in conjunction with the accompanying drawings that illustrate, by way of example, various features of embodiments of the invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is a schematic perspective view showing a heat exchanging system in accordance with an embodiment of the present invention;  
       FIG. 2  is a schematic exploded perspective view showing a laminated structure of a flexible film in accordance with an embodiment of the present invention;  
       FIG. 3  is a schematic perspective view showing a method for manufacturing a flow-path constituting body in accordance with an embodiment of the present invention;  
       FIG. 4  is a schematic perspective view showing a construction example of a part of the flow-path constituting body;  
       FIG. 5  is an enlarged partial cross-sectional view of the construction example shown in  FIG. 4 ;  
       FIG. 6  is a schematic perspective view showing another construction example of a part of the flow-path constituting body;  
       FIG. 7  is an enlarged partial cross-sectional view of the construction example shown in  FIG. 6 ;  
       FIG. 8  is a schematic exploded perspective view showing another construction example of a part of the flow-path constituting body;  
       FIG. 9  is a schematic perspective view showing another construction example of a part of the flow-path constituting body;  
       FIG. 10  is a schematic perspective view showing another construction example of a part of the flow-path constituting body; and  
       FIG. 11  is a plan view showing a flow-path constituting body in accordance with another embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
      Embodiments of the present invention will be described below with reference to the accompanying drawings. Each of the embodiments described below is a flow-path constituting body which is used in a heat exchanging system including a heat receiving part, a heat radiation part and a fluid propulsion means. However, the flow-path constituting body in accordance with the present invention is not limited to the application described above. The flow-path constituting body can be widely applied to a constituting body for constructing a flow path which is arranged as a part of various systems.  
       FIG. 1  is a schematic construction perspective view showing an overview of a heat exchanging system  100  into which a flow-path constituting body in accordance with an embodiment of the present invention is integrated. The heat exchanging system  100  includes a heat receiving part (cooling jacket)  110 , a heat radiation part (radiator)  120 , a cooling fan  130  for blowing airflow to a heat radiation part  120  to forcedly cool, a fluid propulsion means (pump)  140  for circulating fluid (liquid in the embodiment of the present invention), and a flow-path constituting body  150  constructing a flow path between the heat receiving part  110  and the heat radiation part  120 .  
      The heat receiving part  110  is constructed such that a flow path (not shown in the drawing) is formed inside to take heat from a heating part (not shown in the drawing) such as a CPU chip by abutting itself against the heating part. An inlet port and an outlet port are provided on the heat receiving part  110  and port parts  155  and  156  of the flow-path constituting body  150  are connected to the inlet port and the outlet port.  
      The heat radiation part  120  includes an inlet port and an outlet port connected to a flow path constructed in its inside not shown in the drawing. Port parts  151  and  158  of the flow-path constituting body  150  are connected to the inlet port and the outlet port of the heat radiation part  120 . A large number of radiation fins  121  are provided on the outer face of the heat radiation part  120  and heat is diffused outside through the radiation fins  121 . The heat radiation part  120  is constructed so as to receive blown air from a cooling fan  130  having a well-known construction. The airflow generated by the cooling fan  130  is blown to the radiation fins  121  to forcibly cool the heat radiation part  120 .  
      A fluid propulsion means  140  applies propulsion power to a fluid with a drive source such as an electric motor. In the example in  FIG. 1 , the fluid propulsion means  140  is connected to the end portion of the heat radiation part  120  and operates so as to push the fluid introduced from the inlet port of the heat radiation part  120  toward the outlet port of the heat radiation part  120 . The position of the fluid propulsion means  140  is not limited to the example in the drawing and maybe disposed anywhere within a circulation path described later.  
      In the embodiment of the present invention, a circulation path is constructed so as to reciprocate between the heat receiving part  110  and the heat radiation part  120 . The circulation path is constructed by using an integrally-formed flow-path constituting body  150  in the example shown in the drawing. In other words, a forward path and a return path are integrally constructed between the heat receiving part  110  and the heat radiation part  120  by the flow-path constituting body  150 . The flow-path constituting body  150  includes the port parts  155  and  156  connected to the inlet port and the outlet port of the heat receiving part  110 , and the port parts  151  and  158  connected to the inlet port and the outlet port of the heat radiation part  120 . The port parts  151  and  155  are in communication with each other through a flow path  152 , a stagnation part (reserve tank)  153  and a flow path  154 . The port parts  156  and  158  are in communication with each other through a flow path  157 .  
      In the heat exchanging system  100  constructed as described above, the propulsion power is applied to the fluid in the circulation path by the fluid propulsion means  140 , and thus the fluid such as coolant is brought into the inlet port of the heat radiation part  120  from the outlet port of heat receiving part  110  through the flow path  157  to radiate heat at the heat radiation part  120 . The fluid returns from the outlet port of the heat radiation part  120  through the flow path  152 , the stagnation part  153  and the flow path  154  to the heat receiving part  110  again, where heat is taken from the outside.  
      The stagnation part  153  has a function providing an evacuation space for absorbing the volume change of the fluid accompanied with the rise and drop of the fluid temperature, a reserve tank function for supplying the fluid when the fluid decreases due to the volatilization and, when liquid is used as the fluid, a gas storing function for storing gas contained in the liquid or gas generated from the liquid.  
      The flow-path constituting body  150  is constructed such that flexible films  150 X and  150 Y shown in  FIG. 2  are adhesively bonded each other to be formed as a sheet shaped member having flexibility as a whole. The flexible film  150 X or  150 Y is, as shown in  FIG. 2 , is a laminated body, in other words, a laminated film in which resin layers  150 A and  150 C and a metal layer  150 B are laminated together. Thereby, both the gas barrier property (steam barrier property) in the flow path and the deformation strength and the corrosion resistance can be attained while providing flexibility.  
      The resin layers  150 A and  150 C is formed of various types of synthetic resin film. Especially, the synthetic resin film having a heat sealing property such as polyethylene or polypropylene in a polyolefin system is preferable. Also, raw material such as polyester or nylon having a heat sealing property can be used. The resin layers  150 A and  150 C may be made of the same raw material or may be made of different raw material.  
      The metal layer  150 B is preferably comprised of a foil or a thin film (deposited film, spatter film, coating film and the like) which formed of metal such as aluminum, aluminum alloy, copper, copper alloy, silver, silver alloy, gold, and gold alloy.  
      The flexible films  150 X and  150 Y in accordance with the embodiment of the present invention are respectively constructed such that both the front/rear faces of the metal layer  150 B are covered with resin films  150 A and  150 C and thereby the deformation strength or corrosion resistance of the metal layer  150 B can be suitably enhanced. Alternatively, when there is no problem for use, the flexible film  150 X or  150 Y may be constructed such that only one metal layer and one resin layer are laminated.  
      The flow-path constituting body  150  in the present embodiment includes a bonded area in which the flexible films  150 X and  150 Y are directly bonded or bonded with an adhesive and a non-bonded area which is not bonded each other. Especially, the flexible films  150 X and  150 Y are preferably constructed so as to be respectively capable of performing heat seal and adhered (welded) directly. In this case, for example, as shown in  FIG. 3 , heat seal is performed between dies “A” and “B” for the flexible films  150 X and  150 Y. A portion which is pinched and heated by the dies “A” and “B” becomes to be a bonded area  150 T. Since the die “A” is formed with a groove “Aa” and the die “B” is formed with a groove “Ba”, a portion which is not pinched and heated becomes to be non-bonded area  150 S. As constructed above, an arbitrary flow path construction  150   z  can be formed between the flexible films  150 X and  150 Y. For example, as shown in  FIG. 3 , a plurality of flow path constructions  150   z  formed in the non-bonded area  150 S can be simultaneously constructed by the integrally-formed flexible films  150 X and  150 Y. Further, as shown by the dotted line in the drawing, a branched flow path construction  150   v  (portion corresponding to a groove “Ab” of the die “A” and a groove “Bb” of the die “B”) branching off from the halfway of the flow path construction  150   z  can be constructed.  
      The flow path construction  150   z  in the drawing is formed in the non-bonded area  150 S whose both sides are defined by the bonded areas  150 T. Alternatively, the flow path construction may be formed of a piece of flexible film which is bent and folded and thus the non-bonded area may be constructed such that its one side is defined by the bent portion and the other side is defined by the bonded area as described above.  
      Further, a flow path can be similarly constructed easily such that the flexible film described above and another member such as a plate member and a block member are partly bonded to form the bonded area and the non-bonded area. Also in this case, a plurality of flow paths can be simultaneously constructed by the flexible film described above and the above-mentioned another member integrally or complicated flow path constructions including a branch can be integrally constructed. However, when the above-mentioned another member hardly have flexibility, the flow-path constituting body also hardly have flexibility.  
      In  FIG. 1 , the port parts  151 ,  158 ,  155  and  156  provided in the flow-path constituting body  150  are inflow ports or outflow ports constructed at the end portion of the flow paths  152 ,  154  and  157 . In the example shown in the drawing, the respective port parts have a construction that a port member made of synthetic resin or the like is held between the flexible films  150 X and  150 Y. The port member is adhesively fixed or welded to the flexible films  150 X and  150 Y. The port member and the flexible films  150 X,  150 Y are completely sealed up. The port member has a port hole in communication with the flow path. The circulation path is constructed by the port members being connected to the inlet port or the outlet port of the heat receiving part  110  and the heat radiation part  120 .  
      The flow paths  152 ,  154  and  157  constructed in the flow-path constituting body  150  are respectively constructed to form a nearly constant cross section of the flow path in the extended direction. Therefore, the stagnation of the fluid and the occurrence of turbulence can be reduced. However, the flow path is not limited to the construction having its constant cross section. An appropriate flow path construction may be used in which, for example, a part of the cross section of the flow path is enlarged.  
      The flow-path constituting body  150  has flexibility as a whole. However, some rigidity can be obtained especially by the bonded area  150 T where the flexible films are bonded to each other. Therefore, the configuration shown in the drawing can be maintained by itself. In this case, when the area of the bonded area  150 T is increased, the rigidity of the flow-path constituting body  150  increases and, when the area of the bonded area  150 T is decreased, the rigidity of the flow-path constituting body  150  decreases. Therefore, the rigidity and flexibility of the flow-path constituting body  150  can be adjusted depending on the area of the bonded area  150 T. Concretely, in the embodiment of the present invention, the rigidity and flexibility is adjusted by appropriately forming the outside edge configuration or arranging an opening  159  and notched part (slit)  159 ′. Especially, the flexibility of the specified portion of the flow-path constituting body  150  can be enhanced as necessary. For example, in the example shown in the drawing, the flexibility of an area between the flow paths  154  and  157  is enhanced by arranging the opening  159  and the notched portion  159 ′ between the flow paths  154  and  157 , and thus the relative positional relationship of the flow paths can be easily changed. On the contrary, the rigidity of a specified portion can be also enhanced. For example, in the example shown in the drawing, a bonded area is formed between two portions of the stagnation part  153  by forming the stagnation part  153  in a U-shaped configuration. Thereby, the rigidity near the stagnation part  153  is enhanced to be capable of maintaining its configuration to some extent.  
      The opening  159  at an edge part near the flow path  152  and the opening  159  at the upper portion of the stagnation part  153  are formed as engaging holes for supporting the flow-path constituting body  150  with a locking piece or the like not shown in the drawing. The flow-path constituting body  150  may be fixed to another member such as a frame, a support plate, or the heat receiving part  110 , the heat radiation part  120 , the cooling fan  130 , or the fluid propulsion means  140  by various means such as adhesion, deposition, or welding. In this case, it is desirable that the fixed portion of the flow-path constituting body  150  is the bonded area  150 T in order to increase a supporting and fixing force.  
      The flow-path constituting body  150  is connected to other construction parts in the system as shown in  FIG. 1 . Subsequently, a specified amount of fluid is introduced from a fluid inlet port  153   a  and the heat exchanging system  100  is completed. At this time, when the fluid is liquid, it flows into the stagnation part  153  from the fluid inlet port  153   a  and then flows into the respective flow paths  152 ,  154  and  157 . Finally, the fluid is filled in the inside of the heat receiving part  110  and the heat radiation part  120 . Since the fluid inlet port  153   a  is provided at the highest position of the circulation path, the fluid can be filled the entire circulation path by forming an air vent part at an appropriate position. When the liquid is completely filled in the circulation path, the fluid inlet port  153   a  is sealed by adhesion (deposition) after completely removing air within the stagnation part  153 .  
      In this case, it is preferable that the liquid filled in the flow-path constituting body  150  is kept within an amount to some extent less than the maximum capacity of the flow-path constituting body  150 . For example, 90% or less of the maximum capacity is preferably adopted. Thereby, bursting or liquid leakage from the flow-path constituting body can be prevented even when the liquid expands due to the temperature rise of the liquid. Especially, the stagnation part  153  provides a function for preventing an internal pressure from increasing by making the liquid be stored when the liquid expands.  
      In addition, the stagnation part  153  functions as a reserve tank for supplementing the liquid in the flow path when the liquid reduces with lapse of time. The reduction of the liquid can be suppressed to a negligible degree by using the flexible films  150 X and  150 Y constructed of the laminated film as described in the present embodiment having a high sealing property and a gas barrier property (steam barrier property). However, the reduction of liquid can not be avoided even if it is little at coupling portions between the flow-path constituting body  150  and each of other construction parts or in the inside of the respective other construction parts. Therefore, the lifetime of product can be extended by providing the stagnation part  153 .  
      In addition, the stagnation part  153  provides a function for gathering and storing gas such as air mixed in the liquid or various gases discharged from the liquid. This function is inevitably required when liquid is used as fluid. The gathering function of the gas can be also realized by the following evacuation part corresponding to the stagnation part  153  arranged on the side of the flow path as well as the stagnation part  153  as described above provided in the midway of the flow path.  
       FIGS. 4 and 5  are a schematic perspective view and an enlarged cross sectional view showing a constructional example of the evacuation part  150   w  which can be formed at a part of the flow path construction  150   z  of the fluid construction body  150 . The evacuation part  150   w  is formed on the side of the flow path construction  150   z  and constructed such that it is in communication with the flow path construction  150   z  but other portion is closed as a non-bonded area. An aperture part  150   u  of the evacuation part  150   w  to the flow path construction  150   z  is preferably constructed such that its cross section of the opening is formed smaller than both that of the flow path and that of the evacuation part  150   w . The evacuation part  150   w  is provided for preventing bursting of and fluid leakage from the flow-path constituting body  150  by flowing a part of the fluid into it through the aperture part  150   u  when the pressure in the flow path construction  150   z  increases due to the expansion of the fluid.  
      When the flow-path constituting body  150  is installed such that the evacuation part  150   w  is disposed at an upper side of the flow path construction  150   z  as shown in  FIG. 5 , the evacuation part  150   w  can be constructed so that, when liquid is used as fluid, gas contained in the liquid or discharged from liquid is taken into the evacuation part  150   w  and not returned to the flow path again. Thereby, the situation is prevented that the pump can hardly discharge the liquid due to the cause that gas enters and gathers in the pump for flowing the liquid. In this embodiment, it is constructed that gas is hard to return in the flow path by making the aperture part  150   u  small. However, in order to further surely prevent gas from returning to the flow path, a check valve may be incorporated in the aperture part  150   u  of the stagnation part  150   w.    
       FIGS. 6 and 7  are a schematic perspective view and an enlarged cross-sectional view showing the construction example of a flow path construction which is provided with an evacuation part  150   p  different from the above embodiment. The evacuation part  150   p  is, as similar to the evacuation part  150   w , formed on the side of the flow path construction  150   z  and is constructed such that it is in communication with the flow path construction  150   z  and other non-bonded area is closed. In this embodiment, the aperture part of the evacuation part  150   p  to the flow path is formed largely. Concretely, when the evacuation part  150   p  is projected to the flow path construction  150   z , the entire projected plane becomes to be an approximately aperture part. A deformation member  150   q  whose volume reduces due to compressive deformation is accommodated in the inside of the evacuation part  150   p . The deformation member  150   q  can be constructed, for example, by using a flexible bag body within which gas is sealed, flexible porous material such as sponge or the like. The deformation member may be constructed by using a magnet, may be constructed as a heat sink or a heat-radiating body, or may have an additional function as an adsorbent of impurities, a deodorant material, a coloring material or the like.  
      In the construction described above, the volume of the deformation member  150   q  is large as shown by the solid line in  FIG. 7  when the volume or the pressure of the fluid are not so large and thus the evacuation part  150   p  is approximately filled with the deformation member  150   q . Therefore, the fluid flowing through the flow path construction  150   z  circulates within the flow path without stagnation. When the fluid expands or the fluid pressure increases, the deformation member  150   q  is compressed by the fluid pressure as shown by the dotted line in the drawing and thus a part of the fluid enters the inside of the evacuation part  150   p . Thereby, since the increase of the fluid pressure is moderated, the bursting of or the fluid leakage from the flow-path constituting body are reduced.  
       FIG. 8  is an exploded perspective view showing a construction example in which an inner support member  150   i  as a cross-section holding means is disposed in the inside of the flow path construction  150   z  constructed in the flow-path constituting body  150 . The inner support member  150   i  is made of a flexible member formed in a hollow shape which is constructed so as to extend along the flow path direction in the inside of the flow path construction  150   z . In the embodiment shown in the drawing, the inner support member  150   i  is constructed in a spiral shape so as to be extended in the flow path direction. Concretely, the inner support member  150   i  is constructed such that a band shaped member is wound in a spiral shape so as to include a plate surface for supporting the portions of the flexible films  150 X and  150 Y in the non-bonded area.  
      The flowing cross-section of the flow path construction  150   z  is supported from the inner side by disposing the inner support member  150   i  in the inside of the flow path construction  150   z . The inner support member  150   i  is constructed in a hollow shape (cylindrical shape) and thus the fluid flow in the flow path is not obstructed. Also, since the inner support member  150   i  is provided with the flexibility that is capable of being bent in the flow path direction, the flexibility of the flow-path constituting body  150  is not impaired.  
      Alternatively, the inner support member may be constructed so as to be erected in a column shape in the flow path construction  150   z . The cross-section holding means is not limited to the above-mentioned inner support member and may be constructed as an outside support member, which is disposed on the outside of the flow path construction  150   z  for holding and separating one of the flexible films  150 X and  150 Y in the non-bonded area from the other of the flexible films  150 X and  150 Y. The outside support member can be comprised, for example, of a support piece in a circular shape which is fixed on the outer face of the flexible film  150 X to hold the outer face of the flexible film  150 X so as to separate away from the opposed portion of the flexible film  150 Y.  
       FIG. 9  is a schematic perspective view showing a construction example that can be adopted as a construction for the flow-path constituting body  150 . The flow-path constituting body  150  shown in  FIG. 1  constructs a flow path connecting between the heat receiving part  110  and the heat radiation part  120 . However, in the construction shown in  FIG. 9 , an object “M” whose temperature is to be controlled is directly disposed on the outer face of a specified area  150 N in the flow path construction  150   z . The object “M” is, for example, a heating part such as a CPU chip that is to be thermally contacted to the heat receiving part  110  shown in  FIG. 1 . In this construction, a similar function to the heat receiving part  110  shown in  FIG. 1  can be realized by the flow-path constituting body. Especially, since the object “M” whose temperature is to be controlled is directly and thermally contacted on the outer face of the specified area  150 N in the flow path construction  150   z  of the flow-path constituting body, a more satisfactory heat exchange efficiency can be obtained.  
      The specified area  150 N shown in the drawing is constructed in a wide area to be capable of thermally contacting to the object “M” whose temperature is to be controlled over a larger area in accordance with the shape of the object “M”. Thereby, the heat exchange efficiency can be further enhanced. Also, the specified area  150 N and the object “M” may be held by an appropriate holding means for maintaining the state that they are thermally contacted each other. Alternatively, the specified area  150 N and the object “M” may be mutually fixed by means of adhesion with an adhesive or deposition (welding).  
       FIG. 10  is a schematic perspective view showing another construction example that can be adopted as a construction of the flow-path constituting body  150 . In this embodiment, an embedded body  150 L comprised of a magnet or a magnetic substance is disposed between the flexible films  150 X and  150 Y and enclosed by the bonded area. The embedded body  150 L is disposed by the side of the flow path construction  150   z . In this embodiment, at least a part of an object “K” whose temperature is to be controlled is comprised of ferromagnetic substance or magnet and thereby the object “K” is attracted and held by the embedded body  150 L. Accordingly, by means of that the object “K” whose temperature is to be controlled is attracted and held by the embedded body  150 L, the object “K” can be simply held in a thermally contacting state on the flow path construction  150   z  without providing other holding means. Also, according to the construction described above, the object “K” can be simply separated from the flow-path constituting body.  
      The flow-path constituting body in accordance with the above-mentioned embodiment of the present invention can be constructed so as to have various functions by interposing another member between the flexible films  150 X and  150 Y. For example, the rigidity of the sandwiching portion can be enhanced by means of that a reinforcement sheet is sandwiched between the flexible films and the configuration of the flow-path constituting body can be controlled by setting the reinforcement sheet in an appropriate shape. On the contrary, the flow-path constituting body can be constructed so as to be easily capable of partially being bent or folded by enhancing partial flexibility by arranging an aperture part or a slit in a part of the flow-path constituting body.  
       FIG. 11  is a plan view showing a construction of a flow-path constituting body  250  in accordance with another embodiment of the present invention. In the flow-path constituting body  250 , first port parts  251   a ,  251   b ,  251   c , second port parts  252   a ,  252   b  and third port parts  253   a ,  253   b  are respectively formed in different peripheral portions. In this embodiment, the first, the second and the third port part are respectively provided with a plurality of port parts. Flow paths  254   a ,  254   b ,  254   c ,  255   a ,  255   b ,  256   a  and  256   b  are formed between the respective port parts, and a plurality of port parts are respectively constructed so as to be in communication with each other by the flow paths.  
      In the flow-path constituting body  250 , any flow path of the plurality of port parts is connected so as to be mutually in communication with all other port parts. Therefore, a flow path construction as required can be simply realized by appropriately shutting off a portion between the flow paths with pressing or adhesion (welding). For example, when the areas G 1  through G 5  shown by the alternate long and short dash line in the drawing are pressed or adhered (welded), the flow-path constituting body  250  can be constructed such that the first port part  251   a  is in communication with the third port part  253   a  and the first port part  251   b  is in communication with the second port part  252   a  and the third port part  253   b  (branching portion is provided). The pressing of the areas G 1  through G 5  can be performed by using an appropriate clamping tool. In this case, the flow-path constituting body  250  can be restored to its original state. Alternatively, the areas G 1  through G 5  may be thermally welded although they cannot be returned to their original states.  
      The flow-path constituting body in accordance with the present invention is not limited to the embodiments described above and many modifications can be made without departing from the present invention. For example, the heat exchanging system  100  in accordance with the embodiment of the present invention is constructed as a cooling system in which an object whose temperature is to be controlled, not shown in the drawing, is cooled by the heat receiving part  110 . However, the heat exchanging system  100  in accordance with the embodiment of the present invention may be constructed as a heating system in which an object whose temperature is to be controlled is heated by the heat radiation part  120 .  
      Also, in the heat exchanging system, plural heat receiving parts (heat sink) are provided and these plural heat receiving parts can be connected by using the above-mentioned flow-path constituting body. In this case, a plurality of connecting portions can be constructed by using an integrally formed flow-path constituting body. Further, when an object to be cooled does not include a partial hot part but its hot part ranges over a wide area, for example, as the outer packaging portion of a hard disk, the flow-path constituting body itself may be constructed as the heat receiving part as shown in  FIGS. 9 and 10 . According to the construction described above, the connecting portion to the heat receiving part is not required. In this case, the metal layer constructing the flexible film functions as a heat conductive layer.  
      In the embodiments of the present invention as described above, effects such as the reduction of the number of component parts, the reduction of time schedule and the shortening of delivery time can be attained in manufacturing processes by constructing the flow-path constituting body as described above. Also, the flow-path constituting body in accordance with the embodiments of the present invention is superior in flexibility and thus it can be easily provided in various spaces and disposed in a flat passage because of its thin configuration. Accordingly, the flow-path constituting body can be, for example, disposed through the hinge part of a notebook-sized personal computer. In addition, the flow-path constituting body in accordance with the embodiments of the present invention has the following prominent effects. For example, the flow path can be freely constructed such that the cross sectional area of a flow path is appropriately chan in a flow path direction and a plurality of flow paths are constructed in an integral manner, and the flow path is constructed in an appropriate branch structure such as a three-way or a crossroad shaped intersection. Further, the flow-path constituting body can be extremely flexibly dealt in various circumstances because, for example, it can be stuck on various components, it can mount various components thereon, and it can be installed along a recess-projection face.  
      While the description above refers to particular embodiments of the present invention, it will be understood that many modifications may be made without departing from the spirit thereof. The accompanying claims are intended to cover such modifications as would fall within the true scope and spirit of the present invention.  
      The presently disclosed embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims, rather than the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.