Patent Publication Number: US-10333195-B2

Title: Electronic device

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2015-167934, filed Aug. 27, 2015, the entire contents of which are incorporated herein by reference. 
     FIELD 
     Embodiments described herein relate generally to an electronic device comprising an antenna. 
     BACKGROUND 
     An electronic device comprising an antenna inside a housing is well known. The antenna is in contact with an inner surface of the housing. 
     When heat is generated at the antenna during operations, the heat of the antenna is directly transferred to the housing and a surface of the housing may be locally heated at a high temperature. If a heat radiating member is additionally provided to suppress the rise in temperature on the local surface of the housing, space for containing the heat radiating member needs to be secured in the housing. Therefore, the mounting space is increased and space in the housing is reduced. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A general architecture that implements the various features of the embodiments will now be described with reference to the drawings. The drawings and the associated descriptions are provided to illustrate the embodiments and not to limit the scope of the invention. 
         FIG. 1  is a perspective view showing an electronic device of a first embodiment. 
         FIG. 2  is a perspective view of the electronic device shown in  FIG. 1  seen from a cover side. 
         FIG. 3  is a plan view showing an inside of the electronic device with the cover shown in  FIG. 2  removed. 
         FIG. 4  is a plan view showing a state of containing a middle frame in a housing. 
         FIG. 5  is a perspective view showing a state of fixing an antenna on a sheet metal member used in the first embodiment. 
         FIG. 6  is a perspective view showing a state of attaching first and second heat transfer members on the sheet metal member. 
         FIG. 7  is a cross-sectional view seen along line F 7 -F 7  in  FIG. 3 . 
         FIG. 8  is a cross-sectional view seen along line F 8 -F 8  in  FIG. 3 . 
         FIG. 9  is a perspective view showing an electronic device of a second embodiment. 
         FIG. 10  is a front view showing a state of containing the sheet metal member fixed on the antenna in a second housing. 
     
    
    
     DETAILED DESCRIPTION 
     Various embodiments will be described hereinafter with reference to the accompanying drawings. 
     In general, according to one embodiment, an electronic device includes a housing, an antenna, and a sheet metal member. The antenna is contained in the housing with a gap formed between the antenna and the housing. The sheet metal member is supporting the antenna to be thermally connected with the antenna. 
     An electronic device of a first embodiment will be explained hereinafter with reference to  FIG. 1  to  FIG. 8 . In the present embodiment, a tablet PC will be explained as an example of the electronic device. The electronic device is not limited to the tablet PC, but may be the other electronic device such as a television receiver or a digital signage. 
     As shown in  FIG. 1  to  FIG. 4 , an electronic device  1  comprises a housing  2 , and a display panel  3  and an antenna  4  which are contained in the housing  2 . 
     The display panel  3  is shaped in a rectangular flat plate, and comprises a display surface  3 A on which information such as a character and an image is displayed and a back surface  3 B located on a side opposite to the display surface  3 A. 
     The antenna  4  is arranged in close vicinity to an edge portion of the display panel  3 . The antenna  4  used to, for example, high-speed transmission standards such as WiGig and WirelessHD, and the antenna itself generates heat during the operation. The temperature of the antenna  4  of the present embodiment is often raised to, for example, 80° C. and the generated heat amount is larger than that of a conventional antenna. 
     As shown in  FIG. 1  and  FIG. 2 , the housing  2  is formed in a shape of a rectangular flat box, and contains the display panel  3  and the antenna  4 . The housing  2  comprises a front wall  16 , a back wall  17 , and a peripheral wall  18 . 
     The front wall  16  extends on substantially the same plane as the display surface  3 A. An outer surface of the front wall  16  is an example of a first surface  2 A of the housing  2 . The front wall  16  includes a rectangular opening portion  16 A which exposes the display surface  3 A of the display panel  3 . The back wall  17  extends parallel to the front wall  16 . An outer surface of the back wall  17  is an example of a second surface  2 B of the housing  2 . The peripheral wall  18  connects an edge portion of the front wall  16  and an edge portion of the back wall  17 . 
     In the example shown in  FIG. 1  and  FIG. 2 , the housing  2  is composed of a combination of a mask  21  and a cover  22 . The mask  21  includes the front wall  16  while the cover  22  includes the back wall  17 . 
     The cover  22  comprises an antenna cover  24  and a cover body  25 . The antenna cover  24  is formed of, for example, a synthetic resin material. The antenna cover  24  is provided at a position opposed to the antenna  4 . 
     The cover body  25  is a portion of the cover  22  excluding the antenna cover  24 . The cover body  25  is formed of, for example, a magnesium alloy. The material of the cover body  25  is not limited to a magnesium alloy, but the cover body  25  may also be formed of, for example, a synthetic resin material. In this case, the antenna cover  24  and the cover body  25  can be formed as an integrated structure. 
     It should be noted that the electronic device  1  may further comprise a transparent glass panel  27 . The glass panel  27  shown in  FIG. 1  seals the opening portion  16 A of the mask  21  and protects the display surface  3 A of the display panel  3 . 
       FIG. 3  is a plan view showing an inside of the electronic device  1  with the cover  22  removed. Besides the display panel  3  and the antenna  4 , the housing  2  contains a middle frame  28  which covers the back surface  3 B of the display panel  3 , a sheet metal member  30  fixed to the middle frame  28 , a wireless module  32 , a plurality of chip sets  33 , a battery pack, etc. 
     The chip sets  33  are, for example, elements which control the operations of the display panel  3 , etc., and supply the power of the battery pack  35  to the display panel  3 , etc. 
       FIG. 4  is a plan view showing the electronic device  1  having the sheet metal  30 , etc., removed and the middle frame  28  exposed. 
     The middle frame  28  is formed in a rectangular shape smaller than the mask  21  of the housing  2 , and has a heat capacity larger than the sheet metal member  30 . The middle frame  28  is fixed to the mask  21  by a plurality of fastening portions  42 . A plurality of screw holes  44  and bosses  45  for positioning are provided on the middle frame  28 . 
     The middle frame  28  is formed of, for example, a magnesium alloy. If the middle frame  28  is formed of a magnesium alloy, a thermal conductivity is in a range of, for example, 40 to 150 W/(m·K). The middle frame  28  can be formed of not only a magnesium alloy, but, for example, aluminum or a synthetic resin material. 
       FIG. 5  is a perspective view of the sheet metal member  30 . The sheet metal member  30  is formed of a material having a higher thermal conductivity than the middle frame  28 . The material of the sheet metal member  30  is, for example, copper, a copper alloy or a graphite sheet. When the material of the sheet metal member  30  is copper or a copper alloy, a thermal conductivity is in a range of, for example, 200 to 400 W/(m·K). In the example shown in  FIG. 5 , the sheet metal member  30  is formed of copper. 
     The sheet metal member  30  comprises an antenna support portion  51 , a heat diffusion portion  52  continuous to the antenna support portion  51 , and a pair of fixing portions  53  provided at the heat diffusion portion  52 . The antenna support portion  51  is an element which supports the antenna  4 , and has, for example, substantially the same size as the antenna  4 . The heat diffusion portion  52  is formed to be larger than the antenna support portion  51 . The heat diffusion portion  52  includes a first surface  52 A located on the side of the first surface  2 A of the housing  2 , and a second surface  52 B located on an opposite side to the first surface  52 A. 
     The fixing portions  53  are provided at positions remote from the antenna  4 . In the example shown in  FIG. 5 , a fitting hole  56  is provided on the heat diffusion portion  52 . As shown in  FIG. 3 , the fixing portions  53  are fixed to the screw holes  44  of the middle frame  28  by screws  57 . A boss  45  of the middle frame  28  is inserted into the fitting hole  56 . 
       FIG. 6  is a perspective view of the sheet metal member  30  having the antenna  4  excluded from the antenna support portion  51 . A first heat transfer member  61  is adhered to the antenna support portion  51  of the sheet metal member  30 . The first heat transfer member  61  is interposed between the antenna  4  and the antenna support portion  51  to make thermal connection between the antenna  4  and the antenna support portion  51  more certainly. 
     An example of the first heat transfer member  61  is a thermally conductive double-sided tape. The first heat transfer member  61  may be a thermally conductive sheet or thermally conductive grease. If the first heat transfer member  61  is not a thermally conductive double-sided tape, the antenna  4  may be fixed to the antenna support portion  51  by auxiliary means such as a screw. 
     A second heat transfer member  62  is adhered to the first surface  52 A of the heat diffusion portion  52 . An example of the second heat transfer member  62  is a thermally conductive sheet. The second heat transfer member  62  is not limited to a thermally conductive sheet, but may also be a thermally conductive double-sided tape or thermally conductive grease. 
       FIG. 7  is a cross-sectional view showing the antenna  4  mounted in the antenna support portion  51  of the sheet metal member  30  as seen along line F 7 -F 7  in  FIG. 3 . As shown in  FIG. 7 , the second heat transfer member  62  is interposed between the sheet metal member  30  and the middle frame  28  to make thermal connection between the sheet metal member  30  and the middle frame  28  more certainly. 
     In the first embodiment, a gap G is formed between the antenna cover  24  of the housing  2  and the antenna  4 . The gap G has a length of, for example, 0.5 mm. 
     The antenna  4  executes signal transmission to or reception from the antenna cover  24 . No element to disturb the signal transmission/reception is provided in the gap G. An air layer extending the gap G shuts out to prevent the heat of the antenna  4  from transferring to the antenna cover  24 . 
     Furthermore, a gap H is also formed between the cover body  25  of the housing  2  and the heat diffusion portion  52  of the sheet metal member  30 . The cover  22  is therefore thermally separated from the sheet metal member  30 . In the example shown in  FIG. 7 , a gap I is also formed between the mask  21  of the housing  2  and the antenna support portion  51  of the sheet metal member  30 . The mask  21  is therefore thermally separated from the sheet metal member  30 . 
       FIG. 8  is a cross-sectional view showing the wireless module  32  mounted in the middle frame  28  as seen along line F 8 -F 8  in  FIG. 3 . In the example shown in  FIG. 8 , the wireless module  32  comprises a heat generating portion  63 , a connecting portion  64  and a fixed portion  65 . 
     The heat generating portion  63  is electrically connected to the antenna  4  via a cable  66  shown in  FIG. 3  and generates heat in accordance with the operation of the antenna  4 . The connecting portion  64  is provided at one of ends of the heat generating portion  63  and inserted into a connector  67  of the chip set  33 . The fixed portions  65  is provided at the other end of the heat generating portion  63  and fixed to the screw hole  44  of the middle frame  28  by a screw  68 . A gap J is formed between the cover body  25  of the housing  2  and the wireless module  32 . 
     A third heat transfer member  69  is adhered to the heat generating portion  63  of the wireless module  32 . The third heat transfer member  69  is interposed between the sheet metal member  30  and the middle frame  28  to make thermal connection between the wireless module  32  and the middle frame  28 . 
     An example of the third heat transfer member  69  is a thermally conductive sheet. The third heat transfer member  69  is not limited to a thermally conductive sheet, but may also be a thermally conductive double-sided tape or thermally conductive grease. 
     In the electronic device  1  of the present embodiment configured as explained above, direct transfer of the heat generated at the antenna  4  to the housing  2  can be suppressed since the gap G is formed between the antenna  4  and the antenna cover  24  of the housing  2 . Since the antenna  4  is thermally connected to the sheet metal member  30 , the heat generated by the antenna  4  can be dissipated and diffused to the sheet metal member  30  inside the housing  2 . For this reason, even if the communication speed becomes higher and the amount of the heat generation at the antenna  4  is increased, rise in temperature on a local surface of the housing  2  can be suppressed. 
     Furthermore, the sheet metal member  30  comprises both the function of supporting the antenna  4  and the function of diffusing the heat of the antenna  4 . For this reason, a space for mounting the antenna  4  can be compacted as compared with a case of providing the support member which supports the antenna and the heat radiating member which radiates the heat of the antenna, separately, on the housing  2 . 
     In the present embodiment, the thermal connection between the antenna  4  and the antenna support portion  51  is more strengthened due to the presence of the first heat transfer member  61 . For this reason, the heat of the antenna  4  can be certainly dissipated to the sheet metal member  30 . 
     In the present embodiment, the antenna  4  executes signal transmission to or reception from the antenna cover  24  of the housing  2 . The gap G extends between the antenna  4  and the antenna cover  24  in a direction of executing communication by the antenna  4 . For this reason, communication of the antenna  4  is not disturbed inside the housing  2 . 
     In the present embodiment, the sheet metal member  30  is fixed to the middle frame  28  having a larger heat capacity than the sheet metal member  30 . For this reason, the heat transferred from the antenna  4  to the sheet metal member  30  can be efficiently dissipated and diffused to the middle frame  28 . 
     Furthermore, in the present embodiment, the thermal connection between the sheet metal member  30  and the middle frame  28  is more strengthened due to the presence of the second heat transfer member  62 . For this reason, the heat of the antenna  4  transferred to the sheet metal member  30  can be certainly dissipated to the middle frame  28 . 
     In addition, the heat of the wireless module  32  can be efficiently transferred to the middle frame  28  due to the presence of the third heat transfer member  69 . As a result, the operation of the wireless module  32  can be made stable and the reliability of communication of the antenna  4  can be increased. 
     It can be explained from the other viewpoint that the antenna  4  is thermally separated from the housing  2 , in the electronic device  1  of the present embodiment. Since the antenna support portion  51  of the sheet metal member  30  supporting the antenna  4  is sequential with the heat diffusion portion  52  of the sheet metal member  30 , the heat generated by the antenna  4  can be dissipated and diffused from the antenna support portion  51  to the heat diffusion portion  52 . As a result, even if the communication speed becomes higher and the amount of the heat generation at the antenna  4  is increased, rise in temperature on a local surface of the housing  2  can be suppressed. 
     Moreover, in the present embodiment, the heat diffusion portion  52  of the sheet metal member  30  is fixed to the middle frame  28 . Thus, the heat transferred from the antenna  4  to the antenna support portion  51  can be diffused to the heat diffusion portion  52  and then dissipated to the middle frame  28 , and rise in temperature on a part of the middle frame  28  can be suppressed. 
     In other words, the heat generated at the antenna  4  is diffused to the sheet metal member  30  formed of a material having a high thermal conductivity and then dissipated to the middle frame  28 . For this reason, the heat from the antenna  4  can be diffused to the middle frame  28  in a wider area as compared with a case where the antenna  4  is directly supported by the middle frame  28 . As a result, the heat radiation property of the antenna  4  can be further increased. 
     In the present embodiment, the heat diffusion portion  52  is larger in size than the antenna support portion  51 , and secures sufficient heat capacity and heat radiation property. For this reason, rise in temperature on a local surface of the housing  2  can be suppressed more certainly. 
     Second Embodiment 
     An electronic device  100  of a second embodiment will be explained hereinafter with reference to  FIG. 9  and  FIG. 10 . The electronic device  100  of the second embodiment is a clamshell notebook PC. 
     As shown in  FIG. 9 , the electronic device  100  comprises a PC body  102 , a display  103 , and a pair of hinges  104  that couple the PC body  102  and the display  103 . The PC body  102  comprises a first housing  106 , a keyboard  107  provided on the first housing  106 , etc. 
     The display  103  comprises a second housing  108 , and a display panel  110  and an antenna  111  which are contained in the second housing  108 . The antenna  111  is located on an opposite side to the hinge  104 , in the second housing  108 . 
     The second housing  108  is constituted by a combination of a cover  116  which includes an antenna cover  114  and a cover body  115 , and a mask  117 . The antenna cover  114  is provided at a position opposed to the antenna  111  in a thickness direction of the second housing  108 . The antenna cover  114  and the antenna  4  are provided remote from each other so as to be thermally separated from each other. 
       FIG. 10  is a front view of the display  103  with the mask  21  and the display panel  3  cut away in part. In the second embodiment, the display  103  does not comprise a middle frame. A sheet metal member  120  is directly fixed to the cover body  115  of the second housing  108 . 
     The sheet metal member  120  shown in  FIG. 10  is formed to be thinner than the sheet metal member of the first embodiment. The sheet metal member  120  comprises a multilayered portion  121  formed by folding and stacking a sheet metal material, and a heat diffusion portion  122  continuous to the multilayered portion  121 . The multilayered portion  121  is thicker and stronger than the heat diffusion portion  122  which is not formed by folding and stacking a sheet metal material. The multilayered portion  121  is arranged outside the display panel  110  to extend along an edge of the display panel  110 . 
     The multilayered portion  121  comprises an antenna support portion  126  which supports the antenna  111 , and a pair of fixing portions  127  provided remote from the antenna support portion  126 . In the example shown in  FIG. 10 , the fixing portions  127  are fixed to the cover body  115  of the cover  116 . 
     The heat diffusion portion  122  is formed to be thinner and larger than the antenna support portion  126 , and extends along an inner surface of the cover body  115 . 
     In the second embodiment constituted as explained, the heat generated at the antenna  111  can be dissipated and diffused to the heat diffusion portion  122 , similarly to the first embodiment. For this reason, even if the communication speed becomes higher and the amount of the heat generation at the antenna  111  is increased, rise in temperature on a local surface of the second housing  108  can be suppressed. 
     Furthermore, in the second embodiment, the second housing  108  can be made further thinner since the middle frame of the first embodiment can be omitted. 
     In addition, the heat of the antenna  111  can be smoothly diffused by the greatly extending heat diffusion portion  122 . Furthermore, the heat diffusion portion  122  can be made thinner and the second housing  108  can be thinned. In contrast, the antenna  111  can be certainly supported since the antenna support portion  126  is provided on the multilayered portion  121  which is formed to be thicker than the heat diffusion portion  122 . Since the multilayered portion  121  is formed to be thick but arranged at a position displaced from the display panel  3 , the second housing  108  can be maintained in a thin form. 
     Some embodiments of the present invention have been described, but these embodiments are presented as examples, and are not intended to limit the scope of the invention. These novel embodiments can be carried out in various other forms, and can be omitted, replaced and changed in a variety of ways without departing from the spirit of the invention. These embodiments and modifications thereof are included in the claims and spirit of the invention, and also included in the inventions described in the claims and their equivalents. For example, the antenna and the sheet metal member may be contained not in the second housing, but in the first housing, in the second embodiment. If the antenna and the sheet metal member are contained in the first housing, the display may be removed from the electronic device  1 .