Abstract:
According to an aspect, a mobile electronic device includes: a first housing; a second housing; a hinge portion for coupling the first housing and the second housing; and a fuel cell that is mounted to at least either one of the first housing and the second housing, and that uses liquid fuel. The hinge portion has formed thereon a fuel injection port from which the liquid fuel used in the fuel cell can be externally injected.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application is a National Stage of PCT international application Ser. No. PCT/JP2010/073381 filed on Dec. 24, 2010 which designates the United States, and which is based upon and claims the benefit of priority from Japanese Patent Application No. 2009-293386, filed on Dec. 24, 2009. 
     
    
     FIELD 
       [0002]    The present disclosure relates to a mobile electronic device having a fuel cell mounted thereto. 
       BACKGROUND 
       [0003]    There are mobile electronic devices having mounted thereto a fuel cell. An example of the mobile electronic device described above include a mobile phone described in Non Patent Literature 1. The mobile phone described in Non Patent Literature 1 is a so-called flip phone, which has a fuel cell, a fuel tank, and a fuel injection port mounted to a housing that is gripped and where operation buttons are provided. 
       CITATION LIST 
     Non Patent Literature 
       [0004]    Non Patent Literature 1: darkhorse_loga, “No electrical outlets are needed, A mobile phone having incorporated therein a fuel cell that can be charged as soon as possible has been emerged”, [online], 2009.10.6, Gigazine, [2009. 12.3], Internet &lt;URL: http://gigazine.net/index.php?/news/comments/20091006_fuel_cell_ceatec_japan — 2009/&gt; 
       Technical Problem 
       [0005]    When a fuel injection port is formed on the housing that is to be gripped as described in the above-mentioned literature, the size of the housing might increase. 
         [0006]    For the foregoing reasons, there is a need for a mobile electronic device that has mounted thereto a fuel cell, wherein a fuel injection port can be formed without an increase in a size of a housing. 
       SUMMARY 
       [0007]    According to an aspect, a mobile electronic device includes: a first housing; a second housing; a hinge portion for coupling the first housing and the second housing; and a fuel cell that is mounted to at least either one of the first housing and the second housing, and that uses liquid fuel. The hinge portion has formed thereon a fuel injection port from which the liquid fuel used in the fuel cell can be externally injected. 
         [0008]    According to another aspect, the first housing is configured to be capable of being opened and closed about a rotation axis of the hinge portion with respect to the second housing, and the fuel injection port is formed on an end face of the hinge portion in the direction of the rotation axis. 
         [0009]    According to another aspect, the mobile electronic device further includes a fuel tank that can store the liquid fuel injected from the fuel injection port to be supplied to the fuel cell. The first housing has mounted thereto a display unit, and the second housing has mounted thereto an operation portion, and the fuel cell and the fuel tank are mounted to the first housing. 
         [0010]    According to another aspect, the mobile electronic device further includes a control substrate that is mounted to the first housing and that can execute a control process. The first housing has provided thereto a partition that separates the fuel tank from the control substrate. 
         [0011]    According to another aspect, when the first housing and the second housing can be configured to be foldable through the hinge portion, and the closed surfaces of the first housing and the second housing in a folded state are defined as front surfaces of the first housing and the second housing, while the surfaces opposite to the front surfaces are defined as back surfaces of the first housing and the second housing, the display unit includes a main display unit mounted at the front surface side of the first housing, and a sub-display unit mounted at the back surface side of the first housing, and the fuel tank and the sub-display unit are arranged side by side at the back surface side of the first housing along the extending direction of the back surface of the first housing. 
         [0012]    According to another aspect, the mobile electronic device further includes a connection pipe that can be expanded and contracted for connecting the fuel tank and the fuel injection port. 
         [0013]    According to another aspect, a heat exhaust port for exhausting heat generated from the fuel cell is formed on the back surface of the first housing. 
         [0014]    According to another aspect, a thread groove that can be threadably engaged with a fuel supply port of a fuel supply device is formed on the fuel injection port. 
         [0015]    According to another aspect, the fuel injection port is configured through an engagement between an outer injection port member arranged at the outside of the hinge portion in the axial direction and an inner injection port member arranged at the inside from the outer injection port member in the axial direction, and an injection port mounting portion held between the outer injection port member and the inner injection port member is provided to the first housing. 
         [0016]    According to another aspect, the mobile electronic device further includes a sealing cap that is detachably attached to the fuel injection port. 
         [0017]    According to another aspect, the hinge portion couples an end of the first housing and an end of the second housing, the first housing and the second housing are configured to be foldable through the hinge portion, and an outer diameter of the fuel injection port is larger than a thickness of the first housing and a thickness of the second housing, and smaller than a total thickness of the first housing and the second housing when the first housing are folded with respect to the second housing. 
       Advantageous Effects of Invention 
       [0018]    According to the present invention, the mobile electronic device can be formed thin, and the degree of freedom of a layout of components of each housing can be increased, since the fuel injection port is formed on a hinge portion. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0019]      FIG. 1  is a perspective view illustrating an appearance of a mobile electronic device according to an embodiment. 
           [0020]      FIG. 2  is a front view illustrating the mobile electronic device according to the embodiment. 
           [0021]      FIG. 3  is a sectional view illustrating the mobile electronic device illustrated in  FIG. 1  taken along an A plane orthogonal to the widthwise direction. 
           [0022]      FIG. 4  is a sectional view illustrating a first housing of the mobile electronic device illustrated in  FIG. 1  taken along a B plane orthogonal to a longitudinal direction. 
           [0023]      FIG. 5  is a partially exploded view illustrating a fuel tank and a sub-display mounted to a base end of the first housing, and their surroundings. 
           [0024]      FIG. 6  is a partial sectional view illustrating a fuel injection port and its surrounding of the mobile electronic device illustrated in  FIG. 5  taken along a C plane orthogonal to a thickness direction. 
           [0025]      FIG. 7  is a partial sectional view illustrating a fuel injection port and its surrounding of the mobile electronic device illustrated in  FIG. 5  taken along the C plane orthogonal to a thickness direction, when a fuel cartridge is attached thereto. 
           [0026]      FIG. 8  is a partially exploded view illustrating the fuel tank and the sub-display, which are arranged side by side in the longitudinal direction, and their surroundings. 
       
    
    
     DESCRIPTION OF EMBODIMENTS 
       [0027]    The present invention will be described below with reference to the drawings. The present invention is not limited by embodiments (exemplary embodiments) for embodying the present invention. The constituents in the embodiments described below include those easily assumed by a person skilled in the art, those substantially equal to these constituents, and so-called equivalents. A mobile phone will be described below as one example of the mobile electronic device, but a subject to which the present invention is applied is not limited to the mobile phone. The present invention is applicable to PHSs (Personal Handy phone Systems), PDAs (Personal Data Assistants), portable navigation devices, notebook personal computers, and mobile gaming devices. 
         [0028]    (Embodiment) 
         [0029]      FIG. 1  is a perspective view illustrating an appearance of a mobile electronic device according to a present embodiment, and  FIG. 2  is a front view of the mobile electronic device according to the present embodiment. As illustrated in  FIGS. 1 and 2 , the mobile electronic device  1  is a so-called flip phone, and has mounted thereto a fuel cell unit  10  that generates power at the expense of liquid fuel. The mobile electronic device  1  according to the present embodiment will specifically be described below. 
         [0030]    The mobile electronic device  1  includes a first housing  5 , a second housing  6 , and a hinge portion  7  that links one end (base end) of the first housing  5  and one end (base end) of the second housing  6 . The first housing  5  can be opened and closed with respect to the second housing  6  about a rotation axis CL of the hinge portion  7 , whereby the mobile electronic device  1  is configured to be foldable. 
         [0031]    The closed surfaces (the surfaces that face each other) of the first housing  5  and the second housing  6  when they are closed about the hinge portion  7  are front surfaces of the first housing  5  and the second housing  6 , while the surfaces opposite to the front surfaces are back surfaces of the first housing  5  and the second housing  6 . The axial direction of the rotation axis CL of the hinge portion  7  is the same as the widthwise direction (lateral direction) of the first housing  5  and the second housing  6 . The direction orthogonal to the widthwise direction and extended from the base end to a leading end of each of the housings  5  and  6  is a longitudinal direction, while the direction extended from the front surface to the back surface of each of the housings  5  and  6  is a thickness direction. 
         [0032]      FIG. 3  is a sectional view illustrating the mobile electronic device illustrated in  FIG. 1  taken along an A plane orthogonal to the widthwise direction, and  FIG. 4  is a sectional view illustrating the first housing of the mobile electronic device illustrated in  FIG. 1  taken along a B plane orthogonal to the longitudinal direction. As illustrated in  FIG. 3 , the mobile electronic device  1  includes the fuel cell unit  10 , a battery  11 , a display unit  12 , an operation unit  13 , a microphone  14 , a speaker  15 , a receiver  16 , and a control unit  17 , which are mounted to the first housing  5  or to the second housing  6 . 
         [0033]    The first housing  5  mainly has mounted thereto the display unit  12 , the fuel cell unit  10 , and the receiver  16 . The first housing  5  also has mounted thereto a sub-control substrate  17   b  of the control unit  17 . The sub-control substrate  17   b  is an auxiliary control substrate that can control the display unit  12  (see  FIG. 4 ). A sub-display  26  of the display unit  12  described later is mounted on the back surface of the first housing  5 . Although the detail will be described later, the first housing  5  has a heat-exhaust port  40  from which heat generated from the fuel cell unit  10  is exhausted. 
         [0034]    The second housing  6  mainly has mounted thereto the operation unit  13 , the battery  11 , the microphone  14 , and the speaker  15 . The second housing  6  has mounted thereto a main control substrate  17   a  of the control unit  17 . The main control substrate  17   a  is a major control substrate that can control the respective components of the mobile electronic device  1 . 
         [0035]    The hinge portion  7  links a part of the first housing  5  and a part of the second housing  6 . Specifically, the hinge portion  7  includes a bearing portion  20  that moves together with the second housing  6 , and a pair of rotation axis portions  21  and  21  that move together with the first housing  5 . The bearing portion  20  is formed at the center of the base end of the second housing  6  in the widthwise direction. A pair of rotation axis portions  21  and  21  are provided at both sides of the base end of the first housing  5  in the widthwise direction. The bearing portion  20  and the pair of rotation axis portions  21  and  21  are coupled to be rotatable in such a manner that the pair of rotation axis portions  21  and  21  sandwich the bearing portion  20  from both sides. With this structure, the hinge portion  7  can allow the first housing  5  and the second housing  6  to be moved between an open position and a close position about the rotation axis CL. 
         [0036]    In a state where the first housing  5  and the second housing  6  of the mobile electronic device  1  are at the open position, the second housing  6  is gripped by a user. Therefore, the gripped portion of the second housing  6  is closed, while the first housing  5  is exposed. When the first housing  5  and the second housing  6  are at the close position, the mobile electronic device  1  is generally placed onto a desk or the like in a state in which the first housing  5  directs upward and the second housing  6  directs downward. Therefore, the front surface and the back surface of the second housing  6  are closed, while the back surface of the first housing  5  is exposed. 
         [0037]    As illustrated in  FIGS. 1 to 5 , the display unit  12  is mounted on the first housing  5 , and includes a main display  25  and a sub-display  26 . The main display  25  is formed almost all over the front surface of the first housing  5 . On the other hand, the sub-display  26  is formed on one end of the back surface of the first housing  5  in the widthwise direction, and on the base end of the first housing  5 . 
         [0038]    The operation unit  13  includes plural operation keys  28  that are arranged at the front surface side of the second housing  6 . The microphone  14  is arranged at the other end (leading end) of the front surface side of the second housing  6 . The speaker  15  is arranged at the base end of the back surface side of the second housing  6 . The receiver  16  is arranged at the other end (leading end) of the front surface side of the first housing  5 . The battery  11  is arranged at the leading end of the back surface side of the second housing  6 . 
         [0039]    As described above, the control unit  17  includes the main control substrate  17   a  and the sub-control substrate  17   b.  The main control substrate  17   a  is mounted to the second housing  6 , and is arranged between the operation keys  28  arranged at the front surface side and the battery  11  arranged at the back surface side. The sub-control substrate  17   b  is mounted on the first housing  5 , and is arranged between the main display  25  arranged at the front surface side and the sub-display  26  arranged at the back surface side. 
         [0040]    The fuel cell unit  10  is mounted to the first housing  5 , and includes a fuel cell power-generating portion  30 , a fuel tank  31 , a connection pipe  32 , and a fuel injection port  33 .  FIG. 5  is a partially exploded view illustrating the fuel tank and the sub-display mounted on the base end of the first housing, and their surroundings. 
         [0041]    The fuel cell power-generating portion  30  generates power at an expense of liquid fuel. Methanol is used as the liquid fuel, for example. The fuel cell power-generating portion  30  is arranged at the back surface side of the first housing  5  at the leading end, and includes a cell stack having plural fuel cells connected to one another, each fuel cell including a fuel electrode, a solid polymer membrane, and an air electrode. The fuel cell power-generating portion  30  generates electricity through an electrochemical reaction between the liquid fuel and air externally taken in the cell stack. 
         [0042]    As illustrated in  FIG. 1 , a heat exhaust port  40  is formed on the back surface of the first housing  5 , which covers the fuel cell power-generating portion  30 , at the leading end, wherein the heat exhaust port  40  supplies air to the cell stack, and exhaust heat generated from the fuel cell power-generating portion  30 . The heat exhaust port  40  includes plural through-holes  41  that communicate the inside and outside of the first housing  5  with each other. The plural through-holes  41  are formed in a matrix, for example, and each through-hole  41  is circular, for example. Although the plural through-holes  41  are formed in a matrix, the configuration is not limited thereto. The plural through-holes  41  may be formed in staggered alignment. The shape of each through-hole  41  is not limited to be circular. The through-hole  41  may be an elongated hole or a slit. 
         [0043]    With this structure, even when the user grips the mobile electronic device  1 , or even when the mobile electronic device  1  is put on a desk or the like with the sub-display  26  directing upward, the heat exhaust port  40  is hardly closed. Therefore, the heat exhaust port  40  can efficiently take air into the fuel cell power-generating portion  30 , as well as can efficiently exhaust heat generated from the fuel cell power-generating portion  30 . Thus, the power generation efficiency of the fuel cell power-generating portion  30  can be enhanced. 
         [0044]    As illustrated in  FIG. 5 , the fuel tank  31  is a rectangular tank that is formed by resin molding to be thin in the thickness direction. The fuel tank  31  can store liquid fuel therein. The fuel tank  31  is arranged at the base end of the back surface side of the first housing  5 . This structure can make the connection pipe  32  shorter than in the case where the fuel tank  31  is arranged at the leading end of the first housing  5 . The fuel tank  31  and the sub-display  26  are arranged side by side at the back surface side of the first housing  5  in the widthwise direction. The liquid fuel injected from the fuel injection port  33  through the connection pipe  32  is stored in the fuel tank  31 . The liquid fuel stored in the fuel tank  31  is supplied toward the fuel cell power-generating portion  30 , as needed. 
         [0045]    The connection pipe  32  is to connect the fuel injection port  33  and the fuel tank  31 , and is configured by using a bellows expansive pipe. One end of the connection pipe  32  is connected to the fuel injection port  33 , while the other end is connected to the end of the surface of the fuel tank  31  at the base end in the widthwise direction (to the end near the fuel injection port  33 ). This structure can shorten the connection pipe  32 , whereby the layout of the connection pipe  32  can be facilitated. Accordingly, even if the fuel tank  31  is deviated due to external impact, the connection pipe  32  can be expanded or contracted with the positional deviation of the fuel tank  31 , resulting in that the impact resistance of the fuel cell unit  10  can be enhanced. 
         [0046]    As illustrated in  FIGS. 4 and 5 , the first housing  5  includes a liquid-leakage partition  54  that prevents the liquid fuel from leaking toward the sub-control substrate  17   b,  the sub-display  26 , and the main display  25 , when the fuel tank  31  is broken. The liquid-leakage partition  54  includes a front partition  55  arranged at the front surface side of the fuel tank  31 , a side partition  56  arranged around the fuel tank  31 , and a pipe partition  57  arranged at the inside of the connection pipe  32  in the widthwise direction. 
         [0047]    The front partition  55  is formed to be rectangle, and arranged between the fuel tank  31  and the main display  25 . The side wall  56  is arranged on three sides, which are between the fuel tank  31  and the sub-control substrate  17   b  as well as the sub-display  26 , at the leading end side of the fuel tank  31 , and at the base end side of the fuel tank  31 . The pipe partition  57  is arranged to be continuous with the side partition  56  arranged at the base end side of the fuel tank  31  along the extending direction (longitudinal direction) of the connection pipe  32  so as to be located at the inside of the connection pipe  32  in the widthwise direction. 
         [0048]    By virtue of this configuration, the liquid-leakage partition  54  can separate the fuel flowing portion from the fuel injection port  33  toward the fuel tank  31  through the connection pipe  32  from the other portions. Accordingly, even if the fuel tank  31  is broken due to the external impact, or even if the liquid fuel leaks around the connection pipe  32  or the fuel injection port  33 , the liquid-leakage partition  54  can separate the fuel flowing portion from the other portions. Consequently, the liquid-leakage partition  54  can reduce possibility of the leakage of the liquid fuel toward the sub-control substrate  17   b,  the sub-display  26 , and the main display  25 . 
         [0049]    The fuel injection port  33  will next be described with reference to  FIGS. 1 ,  5 , and  6 .  FIG. 6  is a partial sectional view illustrating the fuel injection port and its surrounding of the mobile electronic device in  FIG. 5  taken along a C plane orthogonal to the thickness direction. As illustrated in  FIGS. 1 ,  5 , and  6 , the fuel injection port  33  is provided on an end face  45  of the rotation axis CL of the hinge portion  7 , i.e., on the outer end face  45  in the axial direction of one of the rotation axis portions  21 . 
         [0050]    The fuel injection port  33  includes an outer injection port member  50  mounted at the outside of the hinge portion  7  in the axial direction, an inner injection port member  51  mounted at the inside from the outer injection port member  50  in the axial direction, and an injection-side check valve  52  for preventing flowback of the liquid fuel. A sealing cap  53  is provided at the fuel injection port  33 . 
         [0051]    One of the rotation axis portions  21  of the hinge portion  7  includes a columnar accommodating space R into which the inner injection port member  51  and the outer injection port member  50  are accommodated. The accommodating space R has formed on its inner surface an injection port mounting portion  60  for mounting the fuel injection port  33 . The injection port mounting portion  60  is annularly formed so as to project from the inner peripheral surface of the accommodating space R toward the inside in the diameter direction. The inner injection port member  51  is accommodated in the accommodating space R at the inside in the axial direction, while the outer injection port member  50  is accommodated in the accommodating space R at the outside in the axial direction, across the injection port mounting portion  60 . 
         [0052]    The inner injection port member  51  is formed to be cylindrical with a bottom. The connection pipe  32  is connected to the outer peripheral surface of the inner injection port member  51 . The inside of the inner injection port member  51  and the connection pipe  32  communicate with each other. A thread groove  63  that can be threadably engaged with the outer injection port member  50  is formed on the inner peripheral surface of the inner injection port member  51 . The inner diameter of the inner injection port member  51  is formed to be almost equal to the inner diameter of the injection port mounting portion  60 , while the outer diameter of the inner injection port member  51  is formed to be larger than the inner diameter of the injection port mounting portion  60 . Therefore, the outward movement of the inner injection port member  51  in the axial direction is restricted by the injection port mounting portion  60 . 
         [0053]    The outer injection port member  50  is formed to have a cylindrical shape whose diameter varies in the axial direction. The outer injection port member  50  includes a small-diameter portion  65  located at the inside in the axial direction and having a small diameter, and a large-diameter portion  66  located at the outside in the axial direction and having a large diameter, the small-diameter portion  65  and the large-diameter portion  66  being integrally formed. A screw thread  68  that can be threadably engaged with the inner injection port member  51  is formed on the outer peripheral surface of the small-diameter portion  65 . An injection-side insertion hole  69  through which an axis  77  of the later-described injection-side check valve  52  is inserted is formed through the center axis of the small-diameter portion  65 . A fuel injection channel F 1  through which the liquid fuel flows is formed at the outside of the injection-side insertion hole  69  in the diameter direction. An injection-side spring accommodating portion  70  is formed at the outside of the fuel injection channel F 1  in the diameter direction. The injection-side spring accommodating portion  70  goes to the inside in the axial direction so as to communicate with the inside of the large-diameter portion  66 . A compression spring  78  of the later-described injection-side check valve  52  is accommodated into the injection-side spring accommodating portion  70 . A thread groove  72  that can be threadably engaged with a fuel supply port  81  of a later-described fuel cartridge  80  is formed on the inner peripheral surface of the large-diameter portion  66 . An O-ring  73  with which the fuel supply port  81  of the fuel cartridge  80  is in contact is provided at the bottom of the large-diameter portion  66  at the inside in the axial direction. The outer diameter of the small-diameter portion  65  is formed to be slightly smaller than the inner diameter of the injection port mounting portion  60 , whereby the small-diameter portion  65  can pass through the injection port mounting portion  60  at its inner periphery. The outer diameter of the large-diameter portion  66  is formed to be larger than the inner diameter of the injection port mounting portion  60 . Therefore, the inward movement of the outer injection port member  50  in the axial direction is restricted by the injection port mounting portion  60 . 
         [0054]    As described above, the fuel injection port  33  is configured in such a manner that the small-diameter portion  65  of the outer injection port member  50  is inserted into the injection port mounting portion  60  with the inner injection port member  51  being accommodated in the accommodating space R. Moreover, the outer peripheral surface of the small-diameter portion  65  of the outer injection port member  50  is screwed to the inner peripheral surface of the inner injection port member  51 . Therefore, the injection port mounting portion  60  is held between the inner injection port member  51  and the outer injection port member  50  through the screwed engagement between the inner injection port member  50  and the outer injection port member  51 . Thus, the fuel injection port  33  is fastened to the first housing  5 , whereby resistance to external load can be enhanced. 
         [0055]    The injection-side check valve  52  is provided at the outer injection port member  50 , and includes a disk-like valve portion  75  for covering the end face of the small-diameter portion  65 , a disk-like spring bearing  76  arranged at the inside of the large-diameter portion  66 , and an axis portion  77  that links the center of the valve portion  75  and the center of the spring bearing portion  76 . 
         [0056]    The injection-side check valve  52  includes a compression spring  78  that is provided between the small-diameter portion  65  and the spring bearing portion  76 , and that is accommodated in the injection-side spring accommodating portion  70  of the small-diameter portion  65  to urge the spring bearing portion  76 , and an O-ring  79  attached on the axis portion  77  side of the valve portion  75 . 
         [0057]    The valve portion  75  is configured such that its outer diameter has a size capable of sealing the fuel injection channel F 1 . By virtue of this structure, the compression spring  78  of the injection-side check valve  52  urges the spring bearing portion  76  toward the outside in the axial direction, whereby the valve portion  75  is pressed against the end face of the small-diameter portion  65 . Thus, the injection-side check valve  52  usually seals the fuel injection channel Fl of the small-diameter portion  65 . On the other hand, when the spring bearing portion  76  moves toward the inside in the axial direction against the urging force of the compression spring  78 , the valve portion  75  and the end face of the small-diameter portion  65  are separated. Accordingly, the injection-side check valve  52  releases the sealing of the fuel injection channel F 1  so that the liquid fuel can be flown. 
         [0058]    As illustrated in  FIG. 6 , the sealing cap  53  covers the fuel injection port  33 . The sealing cap  53  includes a cap body  105  formed to have a disk-like shape, and a pair of locking claws  106  and  106  formed at the inside of the cap body  105  in the axial direction. A pair of locking portions  107  and  107  with which the pair of locking claws  106  and  106  of the sealing cap  53  can be engaged is formed on the first housing  5  around the fuel injection port  33 . The pair of locking portions  107  and  107  includes a pair of projecting portions  109  and  109  projecting toward the outside in the diameter direction at the outer peripheral edge at the outside of the outer injection port member  50  in the axial direction, and a pair of recess portions  110  and  110  that can receive the locking claws  106  and  106 , which are formed at the outside in the diameter direction at the inner peripheral edge at the outside of the accommodating space R, accommodating the outer injection port member  50 , in the axial direction. 
         [0059]    With this structure, the sealing cap  53  can seal the fuel injection port  33  through the engagement between the pair of locking portions  107  and  107  formed on the first housing  5  and the pair of locking claws  106  and  106 . Accordingly, the deposition of dusts on the fuel injection port  33  can be reduced, and the outer appearance of the mobile electronic device  1  is not deteriorated. 
         [0060]    Then, a fuel injection operation for injecting the liquid fuel into the thus configured mobile electronic device  1  via the fuel injection port  33  will be described with reference to  FIG. 7 .  FIG. 7  is a partial sectional view illustrating the fuel injection port and its surrounding of the mobile electronic device illustrated in  FIG. 5 , taken along the C plane orthogonal to the thickness direction, when the fuel cartridge is attached thereto. As illustrated in  FIG. 7 , the fuel cartridge  80 , which serves as a fuel supply device for supplying the liquid fuel consumed in the fuel cell power-generating portion  30 , is detachably attached to the fuel injection port  33 . Before the description of the fuel injection operation, the fuel cartridge  80  will be described. 
         [0061]    The fuel cartridge  80  has the fuel supply port  81  at which a supply-side check valve  83  is provided. The fuel supply port  81  is formed to be cylindrical, and has formed on the outer peripheral surface a screw thread  85  that can be threadably engaged with the large-diameter portion  66  of the outer injection port member  50 . A supply-side insertion hole  86  through which an axis  92  of the later-described supply-side check valve  83  is inserted is formed through the center axis of the fuel supply port  81 . A fuel injection channel F 2  through which the liquid fuel flows is formed at the outside of the supply-side insertion hole  86  of the fuel supply port  81  in the diameter direction. A supply-side spring accommodating portion  87 , which accommodates a compression spring  93  of the later-described supply-side check valve  83 , is formed at the outside of the fuel injection channel F 2  of the fuel supply port  81  in the diameter direction. 
         [0062]    The supply-side check valve  83  is provided at the fuel supply port  81 , and includes a disk-like valve portion  90  for covering the inner end face of the fuel cartridge  80  near the supply port, a disk-like spring bearing  91  arranged at the inside of the fuel supply port  81 , and an axis portion  92  that links the center of the valve portion  90  and the center of the spring bearing portion  91 , the valve portion  90 , the spring bearing  91 , and the axis portion  92  being integrally formed. The supply-side check valve  83  includes a compression spring  93  that is provided between the supply-side spring accommodating portion  87  and the spring bearing portion  91 , and an O-ring  94  attached on the axis portion  92  side of the valve portion  90 . 
         [0063]    The valve portion  90  is configured such that its outer diameter has a size capable of sealing the fuel injection channel F 2 . By virtue of this structure, the compression spring  93  of the supply-side check valve  83  urges the spring bearing portion  91  toward the outside in the axial direction, whereby the valve portion  90  is pressed against the end face near the supply port. Thus, the supply-side check valve  83  usually seals the fuel injection channel F 2  of the fuel supply port  81 . On the other hand, when the spring bearing portion  91  moves toward the inside in the axial direction against the urging force of the compression spring  93 , the valve portion  90  and the end face near the supply port are separated. Accordingly, the supply-side check valve  83  releases the sealing of the fuel injection channel F 2  so that the liquid fuel can be flown. 
         [0064]    When the liquid fuel is injected into the mobile electronic device  1 , the screw thread  85  of the fuel supply port  81  of the fuel cartridge  80  is screwed to the thread groove  72  of the fuel injection port  33  of the mobile electronic device  1 . With this, the spring bearing portion  76  of the injection-side check valve  52  provided at the fuel injection port  33  moves toward the inside of the axial direction with respect to the mobile electronic device  1 . Further, the spring bearing portion  91  of the supply-side check valve  83  provided to the fuel supply port  81  moves toward the inside in the axial direction with respect to the fuel cartridge  80 . Accordingly, the fuel injection channel F 1  of the fuel injection port  33  is opened, and the fuel supply channel F 2  of the fuel supply port  81  is opened. Thus, the liquid fuel in the fuel cartridge  80  can be supplied to the fuel tank  31  through the fuel supply port  81  and the fuel injection port  33 . 
         [0065]    Since the fuel injection port  33  is formed on the hinge portion  7 , the mobile electronic device  1  thus configured does not need to form the fuel injection port  33  on the side face of the first housing  5  and the second housing  6 . Therefore, as illustrated in  FIG. 1 , the thickness L 1  of the first housing  5  and the thickness L 2  of the second housing  6  of the mobile electronic device  1  can be reduced more than the diameter L 3  of the fuel injection port  33 . 
         [0066]    Since the fuel injection port  33  is formed on the end face  45  of the rotation axis CL of the hinge portion  7  in the mobile electronic device  1 , the direction of the force applied upon injecting the fuel into the fuel cartridge  80  can be made equal to the axial direction of the rotation axis CL of the hinge portion  7 . With this configuration, even if a great load is applied to the fuel injection port  33 , the mobile electronic device  1  can secure sufficient strength to the load applied upon injecting the fuel, compared to the case where the injection port is formed on the side face of the housing. 
         [0067]    Since the fuel cell unit  10  is mounted on the first housing  5 , the mobile electronic device  1  does not have to increase the thickness L 2  of the second housing  6 . 
         [0068]    Since the liquid-leakage partition  54  is provided to the first housing  5 , the mobile electronic device  1  can not only separate the fuel tank  31  from the sub-control substrate  17   b,  but also separate the fuel flowing portion, which is from the fuel injection port  33  to the fuel tank  31  through the connection pipe  32 , from the other portions. 
         [0069]    Since the fuel tank  31  and the sub-display  26  are arranged side by side in the widthwise direction at the back surface side of the first housing  5 , the mobile electronic device  1  can realize an efficient layout in which the first housing  5  can be made thin. In the present embodiment, the fuel tank  31  and the sub-display  26  are arranged side by side in the widthwise direction. However, the arrangement is not limited thereto. For example, the fuel tank  31  and the sub-display  26  may be arranged side by side in the longitudinal direction as illustrated in  FIG. 8 . 
         [0070]    Since the connection pipe  32  is expandable, it can be expanded and contracted with the positional deviation of the fuel tank  31 , whereby the resistance to the external impact can be enhanced. 
         [0071]    Since the heat exhaust port  40  is formed on the back surface of the first housing  5  of the mobile electronic device  1 , the heat exhaust port  40  is hardly closed by a user. 
         [0072]    Since the fuel supply port  81  of the fuel cartridge  80  is screwed to the fuel injection port  33  of the mobile electronic device  1 , the fuel cartridge  80  is difficult to be detached. 
         [0073]    Since the fuel injection port  33  can be formed between the outer injection port member  50  and the inner injection port member  51  across the injection port mounting portion  60  of the first housing  5 , the resistance to the external load can be enhanced. 
         [0074]    Since the sealing cap  53  that is detachable can be attached to the fuel injection port  33 , the deposition of dusts on the fuel injection port  33  can be prevented. The outer appearance of the mobile electronic device  1  can also be made good. 
         [0075]    The diameter L 3  of the fuel injection port  33  is larger than the thickness L 1  of the first housing  5  and the thickness L 2  of the second housing  6 , and smaller than the total thickness (L 1 +L 2 ) of the first housing  5  and the second housing  6 . Therefore, even if the fuel injection port  33  is formed on the hinge portion  7 , the increase in the thickness of the mobile electronic device  1  can be prevented. 
         [0076]    In this case, the fuel tank  31  and the battery  11  may be arranged not to be superimposed on each other in the thickness direction, when the first housing  5  and the second housing  6  of the mobile electronic device  1  are on the closed position. By virtue of this, the weight balance of the mobile electronic device  1  that is closed can be stabilized. 
         [0077]    In the present embodiment, the sub-display  26  is mounted on the back surface of the first housing  5 . However, the sup-display  26  may not be provided. In the present embodiment, the fuel cartridge  80  is attached by the screw engagement between the thread groove  72  formed on the fuel injection port  33  of the mobile electronic device  1  and the screw thread  85  formed on the fuel supply port  81  of the fuel cartridge  80 . However, the thread groove  72  and the screw thread  85  may not be formed, and the liquid fuel may be injected by pressing the fuel supply port  81  of the fuel cartridge  80  against the fuel injection port  33  of the mobile electronic device  1 . 
         [0078]    The clamshell type mobile electronic device  1  has been described above, but a mobile electronic device of another type may be employed. For example, the present invention can be applied to a revolver type in which two housings are superimposed in the thickness direction, and a hinge portion is provided so as to relatively rotate the two housings about a rotation axis along the thickness direction. 
       Industrial Applicability 
       [0079]    As described above, the present invention is well adaptable to a mobile electronic device having mounted thereto a fuel cell, and more particularly, well adaptable to reduce a thickness of a mobile electronic device.