Abstract:
The present invention provides a small electronic device including a cabinet body having a battery chamber defined therein, and a battery pack having a battery that is to be received in the battery chamber and is integrated with a battery lid for covering the battery chamber. The battery lid is detachably engaged with the cabinet body. A support plate for receiving the battery is placed on the bottom face of the battery chamber. An opening is centrally defined on the support plate.

Description:
[0001]    The priority application Number 2007-093792 upon which this patent application is based is hereby incorporated by reference. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to small electronic devices such as portable telephones. 
         [0004]    2. Description of Related Art 
         [0005]    A conventional portable telephone includes, as shown in  FIG. 5 , a cabinet body  101  having a battery chamber defined therein, and a battery pack  103  having a battery  108  to be received in the battery chamber and a battery lid  109  for covering the battery chamber that are integrated together by ultrasonic welding. 
         [0006]    The cabinet body  101  includes two side plate portions  110 ,  110  at both ends, and has a support plate  111  placed on the bottom of the battery chamber. The battery pack  103  is detachably attached in the battery chamber of the cabinet body  101 . 
         [0007]    The battery  108  includes a battery body  112  and a battery case  113  storing the battery body  112 . As shown in  FIG. 6 , the battery lid  109  includes a main plate portion  114  and two side plate portions  115 ,  115  projecting from both ends of the main plate portion  114 . The battery lid  109  has the battery  108  and the main plate portion  114  of the battery lid  109  integrated together by ultrasonic welding. 
         [0008]    However, there has been a problem of a gap G, as shown in  FIG. 5 , being defined between the side plate portions  110 ,  110  of the cabinet body  101  and the side plate portions  115 ,  115  of the battery lid  109 . This can be caused by the battery pack  103  being used under high temperature and high humidity environments and the battery  108  being thereby expanded in the thickness direction as indicated by a two-dot chain line in  FIG. 7 , resulting in the battery  108  expanded in the thickness direction pressing the support plate  111  and pushing up the battery lid  109 . 
       SUMMARY OF THE INVENTION 
       [0009]    The present invention provides a small electronic device including a cabinet body having a battery chamber R, and a battery pack having a battery that is to be received in the battery chamber R and is integrated with a battery lid for covering the battery chamber R. The battery lid is detachably engaged with the cabinet body. A support plate for receiving the battery is placed on the bottom face of the battery chamber R. An opening is centrally defined on the support plate. 
         [0010]    The small electronic device of the present invention can prevent the battery lid from being pushed up because the opening is centrally defined on the support plate and therefore the expanded portion of the battery pack expanded in the thickness direction is received in the opening. The side plate portions of the battery lid and the side plate portions of the cabinet body will therefore not define a gap G. 
         [0011]    In another specific configuration, the support plate is made of metal. This specific configuration allows the support plate to have mechanical strength equivalent to or greater than that in the case of use of a synthetic resinous material, as well as allowing the support plate to be thinner. 
         [0012]    In still another specific configuration, a first substrate and a second substrate are arranged on opposite sides across the battery chamber R inside the cabinet body, with one of the substrates being connected to a ground potential. The first substrate and the second substrate are electrically connected to each other by the support plate. This specific configuration allows both the first substrate and the second substrate to be connected to a ground potential. 
         [0013]    In still another specific configuration, the first substrate is an antenna substrate having an antenna incorporated therein, and the second substrate is a high frequency substrate for performing communication processing using the antenna. This specific configuration can reduce noise during communication by the antenna substrate and the high frequency substrate. 
         [0014]    As described above, the small electronic device of the present invention will not have a gap defined between the side plate portions of the cabinet body and the side plate portions of the battery lid even in use under high temperature and high humidity environments. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0015]      FIG. 1  is a perspective view of a foldable portable telephone of the present invention; 
           [0016]      FIG. 2  is an exploded perspective view of an operation housing of the foldable portable telephone; 
           [0017]      FIG. 3  is an exploded perspective view showing a battery pack; 
           [0018]      FIG. 4  is a sectional view of the operation housing in the portable telephone embodying the present invention; 
           [0019]      FIG. 5  is a sectional view of an operation housing in a conventional portable telephone; 
           [0020]      FIG. 6  is a perspective view showing a battery lid and a battery that are to be ultrasonically welded; and 
           [0021]      FIG. 7  is a sectional view showing an expanded battery. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0022]    The present invention embodied in a foldable portable telephone is now described with reference to the drawings. As shown in  FIG. 1 , a foldable portable telephone of the present invention has an operation housing  1  and a display housing  2  that are openably and closably coupled to each other via a hinge mechanism  3 . 
         [0023]    The operation housing  1  includes a battery pack  4 , and has a plurality of operation buttons (not shown) arranged on the facing surface to the display housing  2 . The display housing  2  has a main display (not shown) arranged on the facing surface to the operation housing  1 , and has a sub display  20  arranged on the back face of the display housing  2 . 
         [0024]    As shown in  FIG. 2 , the foldable portable telephone of the present invention includes a cabinet body  14  of the operation housing  1  that includes a battery chamber R and two side plate portions  11 ,  11  projecting from both ends of the battery chamber R. The cabinet body  14  has an antenna substrate  53  and a high frequency substrate  52  that are arranged on opposite sides across the battery chamber R. The antenna substrate  53  and the high frequency substrate  52  are electrically connected to each other by a coaxial cable  7 . The coaxial cable centrally includes a wire exposed portion  7   a  for grounding. 
         [0025]    A support plate  6  made of stainless steel and centrally having an opening  61  is placed in the battery chamber R. Two first coupling pieces  62 ,  62  and two second coupling pieces  63 ,  63  project from both ends of the support plate  6 . The two first coupling pieces  62 ,  62  are coupled to the high frequency substrate  52 , and the two second coupling pieces  63 ,  63  are coupled to the antenna substrate  53 . 
         [0026]    The support plate  6  supports the antenna substrate  53  and the high frequency substrate  52  via the first coupling pieces  62 ,  62  and the second coupling pieces  63 ,  63 . The coaxial cable  7  is placed between the support plate  6  and the bottom of the battery chamber R. 
         [0027]    The support plate  6  is electrically connected to the wire exposed portion  7   a  of the coaxial cable  7  to thereby connect the antenna substrate  53  and the high frequency substrate  52  to a ground potential via the support plate  6 . Further, heat dissipation effect on the high frequency substrate  52  is given by the support plate  6  being coupled to the high frequency substrate  52  via the first coupling pieces  62 ,  62 . 
         [0028]    The antenna substrate  53  is covered with an antenna substrate cover  13 . The high frequency substrate  52  is covered with a high frequency substrate cover  12 . Two tongues  15 ,  15  project from an end of the high frequency substrate cover  12 . The two tongues  15 ,  15  cover both ends of the hinge mechanism  3 . 
         [0029]    The battery pack  4  is detachably received via the support plate  6  in the battery chamber R of the cabinet body  14 . Two nail pieces  17 ,  17  project from an end of the battery lid  41 , and are inserted into two connection holes (not shown) provided on an end face of the high frequency substrate cover  12  that faces the battery chamber R. The antenna substrate cover  13  has a lock mechanism  16  for locking the battery pack  4 . The lock mechanism  16  detachably locks the battery pack  4 . 
         [0030]    As shown in  FIG. 3 , the battery pack  4  includes a battery  42  and a battery lid  41  joined to the battery  42  by ultrasonic welding. The battery  42  includes a battery body  43  and a battery case  44  storing the battery body  43 . The battery lid  41  has a main plate portion  45  ultrasonically welded to the battery  42  and two side plate portions  46 ,  46  connected to both ends of the main plate portion  45 . The two nail pieces  17 ,  17  to be inserted into the two connection holes of the high frequency substrate cover  12  project from an end of the main plate portion  45 . 
         [0031]    The battery pack  4  will be expanded in the thickness direction by using the battery pack  4  received in the battery chamber R of the cabinet body  14  under high temperature and high humidity environments. In the case of the conventional portable telephone  100 , as shown in  FIG. 5 , the expansion of the battery pack  103  causes the battery pack  103  to press the support plate  111  covering the inside of the battery chamber R of the cabinet body  101 , causing the reaction force thereof to raise the battery pack  103  outward from the battery chamber R. This results in each gap G being defined between the side plate portions  115 ,  115  of the battery lid  109  and the side plate portions  110 ,  110  of the cabinet body  101 . 
         [0032]    In contrast, in the case of the portable telephone of the present invention, as shown in  FIG. 4 , the opening  61  accommodates the expanded portion of the expanded battery pack  4  to thereby mitigate the force pressing the bottom face of the battery chamber R. This results in reducing the reaction force from the support plate  6  and the battery chamber R, preventing the battery pack  4  from being raised outward from the battery chamber R. This results in preventing a gap G from being defined between the side plate portions  46 ,  46  of the battery lid  41  and the side plate portions  11 ,  11  of the cabinet body  14 . 
         [0033]    The size of the opening  61  is determined in view of the strength of the material of the support plate  6 , and may be at least within a range in which the support plate  6  can maintain mechanical strength to support the antenna substrate  53  and the high frequency substrate  52 . 
         [0034]    The present invention is not limited to the foregoing embodiment in construction but can be modified variously without departing from the spirit of the invention as set forth in the appended claims. Although the present invention embodied in a foldable portable telephone is described in the above described embodiment, the present invention is not limited to this but can be carried out in small electronic devices such as PHSs (Personal Handyphone Systems), laptop personal computers or the like.