Abstract:
A mobile electronic device is disclosed. A housing comprises a circuit board located inside the housing. Protection means protects an electronic component located on the circuit board and exposed externally through an external opening in the housing.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     The present application claims priority under 35 U.S.C. §119 to Japanese Patent Application No. 2010-016032, filed on Jan. 27, 2010, entitled “MOBILE ELECTRONIC DEVICE”. The content of which is incorporated by reference herein in its entirety. 
     FIELD 
     Embodiments of the present disclosure relate generally to mobile electronic devices, and more particularly relate to a mobile comprising an electronic component. 
     BACKGROUND 
     A conventional mobile electronic device such as a mobile phone may comprise a housing and a circuit board housed inside the housing. When an electronic component is exposed externally, static electricity may enter the electronic component; hence, there is a possibility that the electronic component will be adversely affected. 
     SUMMARY 
     A mobile electronic device from static electricity is disclosed. 
     In an embodiment, a mobile electronic device comprises a housing, a circuit board, a first electronic component, and a reference potential section, an opening is formed in the housing. The circuit board is located inside the housing and on which electronic components are mounted. The first electronic component is mounted on the circuit board and is exposed to the outside of the housing via the opening. The reference potential section is located inside the housing and is electronically connected to the reference potential. With regard to the housing, the opening is formed, and at the same time, a partition section to partition said the electronic component and the reference potential section is formed. The housing comprises a partition section forming the opening and partitioning the first electronic component and the reference potential section. The partition section comprises a through-hole penetrating the side on which the first electronic component is located and the side on which the reference potential section is located. The impedance between the outer edge region in which the through-hole of the partition section is formed and the reference potential section is lower than the impedance between the outer edge region in which the through-hole of the partition section is formed and said the electronic component. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Embodiments of the present disclosure are hereinafter described in conjunction with the following figures, wherein like numerals denote like elements. The figures are provided for illustration and depict exemplary embodiments of the present disclosure. The figures are provided to facilitate understanding of the present disclosure without limiting the breadth, scope, scale, or applicability of the present disclosure. The drawings are not necessarily made to scale. 
         FIG. 1  is an illustration of a perspective view of an electronic mobile device showing a front side thereof according to an embodiment of the disclosure. 
         FIG. 2  is an illustration of a perspective view of an electronic mobile device showing a rear side thereof according to an embodiment of the disclosure. 
         FIG. 3  is an illustration of an exploded perspective view an electronic mobile device according to an embodiment of the disclosure. 
         FIG. 4  is an illustration of a partially enlarged view of a region A from  FIG. 2  in which a cover is removed according to an embodiment of the disclosure. 
         FIG. 5  is an illustration of a cross-sectional view along a line B-B of  FIG. 3 . 
         FIG. 6  is an illustration of cross-sectional view along a line C-C of  FIG. 3  according to an embodiment of the disclosure. 
         FIG. 7  is an illustration of an electronic mobile device showing distance relationship between respective components thereof according to an embodiment of the disclosure. 
         FIG. 8  is an illustration of a circuit diagram according to an embodiment of the disclosure. 
         FIG. 9  is an illustration of a graph showing a reference potential pattern layer according to an embodiment of the disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     The following description is presented to enable a person of ordinary skill in the art to make and use the embodiments of the disclosure. The following detailed description is exemplary in nature and is not intended to limit the disclosure or the application and uses of the embodiments of the disclosure. Descriptions of specific devices, techniques, and applications are provided only as examples. Modifications to the examples described herein will be readily apparent to those of ordinary skill in the art, and the general principles defined herein may be applied to other examples and applications without departing from the spirit and scope of the disclosure. The present disclosure should be accorded scope consistent with the claims, and not limited to the examples described and shown herein. 
     Embodiments of the disclosure are described herein in the context of one practical non-limiting application, namely, a mobile phone. Embodiments of the disclosure, however, are not limited to such mobile phone, and the techniques described herein may also be utilized in other applications. For example, embodiments may be applicable to, digital books, digital cameras, electronic game machines, digital music players, personal digital assistance (PDA), personal handy phone system (PHS), lap top computers, and the like. 
     As would be apparent to one of ordinary skill in the art after reading this description, these are merely examples and the embodiments of the disclosure are not limited to operating in accordance with these examples. Other embodiments may be utilized and structural changes may be made without departing from the scope of the exemplary embodiments of the present disclosure. 
     Below, a preferred embodiment of the present invention is explained with reference to the figures. First,  FIG. 1  and  FIG. 2  explain the basic configuration of the mobile phone  1  as a mobile electronic device.  FIG. 1  is a perspective view for explaining the front side of the mobile phone  1 .  FIG. 2  is a perspective view for explaining the rear side of the mobile phone  1 . 
     As shown in  FIG. 1  and  FIG. 2 , the mobile phone  1  comprises a housing  2 . 
     As shown in  FIG. 1 , the mobile phone  1  comprises an operation section  11  that is located on the front side  10 A of the housing  2  (key operation section), a display section  21 , a speaker  22 , and a microphone  23 . 
     The operation section  11  comprises a plurality of keys. The operation section  11  comprises a function setting operation key  13  for operating various functions such as various setting functions, a dictionary function, or e-mail function, an input operation key  14  for entering numbers and characters, and a decision operation key  15  that makes a decision for various operations and that performs scrolling, etc. The key group comprising the operation section  11  is located toward one side of the housing  2  in the longitudinal direction Y. The operation section  11  detects various inputs. 
     The display section  21  is, for example, a liquid-crystal display, or an EL (electroluminescence) display, etc. The display section  21  is located toward another end of the housing  2  in the longitudinal direction Y. The display section  21  is located side-by-side with the key group comprising the operation section  11  in the longitudinal direction Y. 
     The display section  21  displays various types of information (character information and image information) such as the telephone number, e-mail address of a receiver, and e-mail contents. 
     The speaker  22  is located in the vicinity of one end of the housing  2  in the longer direction Y. The speaker  22  outputs the voice of the receiver. 
     The microphone  23  is located in the vicinity of another end of the housing  2  in the longitudinal direction Y. The microphone  23  is used in order to input the voice that a user of the mobile phone  1  emits during a call. 
     As shown in  FIG. 2 , the mobile phone  1  comprises a camera section  29  located on the rear side  10 B of the housing  2 . 
     The camera section  29  is located on one end of the housing  2  in the longitudinal direction Y. The camera section  29  is located so as to be superimposed with the speaker  22  in the thickness direction Z of the housing. The camera section  29  images a photographic object set by a user. 
     On the rear side  10 B of the housing  2 , a battery lid  2   c , which is explained subsequently, is attached detachably. 
     Next, in  FIG. 3 , the internal configuration of the mobile phone  1  is explained.  FIG. 3  is an exploded perspective view of the mobile phone  1 . 
     As shown in  FIG. 3 , the housing  2  comprises a front case  2   a , a key structure section, which is not shown in the figures, a key substrate  50 , a shield case  60 , a circuit board  70 , an antenna section, which is not shown in the figures, a rear case  2   b , a battery  81 , and a battery lid  2   c.    
     As shown in  FIG. 3 , the housing  2  comprises, as a case member constituting an outline, the front case  2   a , the rear case  2   b , and the battery lid  2   c.    
     The front case  2   a  and the rear case  2   b  are located such that the respective hollow inner sides face each other and are combined such that the respective outer edges overlap. 
     Moreover, on the outer surface (the rear side  10 B) of the rear case  2   b , the battery lid  2   c  is attached to the rear case  2   b  detachably. 
     On the rear case  2   b , in a state in which the battery lid  2   c  is removed, an opening section  100  that is exposed externally, a wall section  300 , and a through-hole  310  are formed (refer to  FIG. 3  to  FIG. 6 ). These are explained subsequently. 
     As shown in  FIG. 3 , inside the housing  2 , a key structure section, which is not shown in the figures, the key substrate  50 , the shield case  60 , the circuit board  70 , the antenna section, which is not shown in the figures, and the battery  81  are located. 
     In the present embodiment, the key substrate  50  is stacked and located toward the side of the first surface  70   a , which is one end of the circuit board  40  in the longitudinal direction Y. 
     Moreover, the shield case  60  is located integrally so as to fit the rear case  2   b.    
     Next, each component is explained. 
     The key structure section comprises an operation member (key top), a key frame as a reinforced member, and a key sheet as a sheet member. 
     The key substrate  50  comprises a plurality of key switches. The plurality of key switches are located at the position corresponding to the operation member, respectively. The key switches located on the key substrate  50  are configured so as to comprise a metal dome, which is a metal plate formed three-dimensionally by curving in a bow-shape. 
     The shield case  60  is a conductive member. The shield case  60  comprises a plate section and a rib. The rib is formed so as to abut a reference potential pattern layer  75 , which is described subsequently, in the state in which the shield case  60  is placed on the circuit board  70 . The shield case  60  inhibits noise such as the high frequency waves emitted from the outside, etc., from acting on various electronic components located on the circuit board  70 , and shields the noise emitted from the RF (radio frequency) circuit, CPU circuit, power circuit, etc., formed on the circuit board  70 . 
     On the circuit board  70 , various electronic components are mounted, and the RF (radio frequency) circuit, CPU circuit, power circuit, etc., are formed. 
     On the second surface  70   b  (mounting side) of the circuit board  70 , an RF connector  200  (terminal) as the first electronic component, an electronic component  210  as the second electronic component, an electronic component  220  as the third electronic component, etc., which are described subsequently, are mounted. Moreover, on the second surface  70   b  (mounting side) of the circuit board  70 , the reference potential pattern layer  75  is formed. The reference potential pattern layer  75  is formed, for example, by printing the conductive members on the surface of the second surface  70   b  of the circuit board  70 . 
     The antenna section comprises an antenna element arranged in a predefined shape on the base. The antenna element of the antenna is formed by a belt-shaped metal plate. Moreover, the antenna is fed from the circuit board  70  via a feed terminal, which is not shown in the figures. 
     Next, by referring to  FIG. 4  to  FIG. 8 , the static control configuration in the region A comprising the RF connector  200  as the first electronic component mounted on the second surface  70   b  (mounting side) of the circuit board  70  is explained. 
       FIG. 4  is a partially enlarged view of the region A from  FIG. 2  in the state in which the cover member is removed.  FIG. 5  is a B-B cross-sectional view of  FIG. 3 .  FIG. 6  is a C-C cross-sectional view of  FIG. 3 .  FIG. 7  is a schematic diagram explaining the distance relationship between the respective components themselves.  FIG. 8  is a circuit diagram explaining the circuit in which the RF connector is connected. 
     As shown in  FIG. 4  to  FIG. 6 , on the rear case  2   b , the opening section  100  that is exposed externally in the state in which the battery lid  2   c  is removed is formed. The opening section  100  is formed by penetrating from one side of the rear case  2   b  to the other side. The opening section  100  is formed so as to externally expose the RF connector  200  (terminal) as the first electronic component that is mounted on the circuit board  70 , in the state in which the battery lid  2   c  is removed. 
     As shown in  FIG. 4  to  FIG. 6 , the RF connector  200  as the first electronic component is mounted on the second surface  70   b  (mounting side) of the circuit board  70 . The RF connector  200  exposes externally via the opening section  100  in a state in which the battery lid  2   c  is removed. 
     The RF connector  200  is mounted on the second surface  70   b  (mounting side) of the circuit board  70  such that the side surface is surrounded by the wall section  300  as a partition section, which is described subsequently, formed continuously at the outer edge of the opening section  100  so as to extend to the circuit board  70  side. In other words, the RF connector  200  is surrounded by the second surface  70   b  of the circuit board  70  and the wall section  300 . 
     As shown in  FIG. 4  to  FIG. 6 , the wall section  300  as the partition section forms the opening section  100  and is located so as to partition the RF connector  200  and the shield case  60 . 
     The wall section  300  is formed continuously at the outer edge of the opening section  100 . so  as to extend to the circuit board  70  side The wall  300  is located so as to surround the side surface of the RF connector  200 . 
     Moreover, the wall section  300  is formed so as to partition the RF connector  200  and the shield case  60 , which is described subsequently. 
     On the wall section  300 , the through-hole  310  is formed. 
     As shown in  FIG. 6 , on the second surface  71   b  (mounting side) of the circuit board  70 , the shield case  60  is mounted as the reference potential section. Specifically, the shield case  60  is mounted on the second surface  71   b  (mounting side) of the circuit board  70  in the state in which the bottom surface  60   a  abuts on the reference potential pattern layer  75  formed on the circuit board  70 . In the present embodiment, the shield case  60  is used as a member to transmit static electricity from the outside. 
     The shield case  60  comprises a sharp end section  65  formed to be sharp so as to project toward the region in which the through-hole  310  of the wall section  300  is formed (including the outer edge region of the through-hole  310  and an inner side  310   a  which is described later). In the present embodiment, the sharp end section  65  is preferable because it easily transmits static electricity. 
     The shield case  60 , as the original function, shields the electronic component  220  (refer to  FIG. 7 ) as the third electronic component. Specifically, the shield case  60  is disposed so as to surround the electronic component  220  as the third electronic component, and shields the electronic component  220  as the third electronic component that is surrounded by the shield case  60  from high frequency wave noise, etc. 
     The through-hole  310  is formed on the wall section  300 . 
     The through-hole  310  is formed by penetrating the side on which the RF connector  200  is located on the wall section  300  and the side on which the shield case  60  is located. 
     The through-hole  310  is formed at the end section of the second surface  70   b  in the wall section  300 . In other words, the through-hole  310  is formed so as to extend to the side on which the battery lid  2   c  is located from the second surface  70   b.    
     The through-hole  310  is formed by penetrating the region facing the RF connector  200 , specifically the side on which the RF connector  200  is located on the wall section  300  and the region facing the shield case  60 , specifically the side on which the shield case  60  is located. In other words, the through-hole  310  is formed in the area that is sandwiched between the RF connector  200  and the shield case  60 . 
     On a region AR 1  facing the inner side  310   a  of the through-hole  310  on the second surface  70   b  of the circuit board  70 , the electronic component  210  as the second electronic component is mounted. 
     The region AR 1  is the region that becomes possible to mount the electronic component by comprising the through-hole  310  formed. That is, the region AR 1  is the mountable region which has become wide to mount the electronic components by comprising the through-hole  310  formed. 
     The electronic component  210  as the second electronic component is mounted on the region AR 1 . That is, the electronic component  210  is the electronic component that can be mounted by comprising the through-hole  310  formed. 
     Next, by referring to  FIG. 7 , the distance relationship between the respective elements is described. 
     As shown in  FIG. 7 , on a presumed route R 1  where the static electricity enters from an entry section P 1  flows, the distance between an outer edge region P 2  which is located closest to the respective element and the respective element is as follows. The outer edge region P 2  is part of the outer region (including the outer edge of the through-hole  310  and the inner side  310   a ) in which the through-hole  310  of the wall section  300  is formed. 
     A distance L 1  between the outer edge region P 2  and the sharp end section  65  of the shield case  60  is shorter than a distance L 3  between the outer edge region P 2  and a predefined section  200   a  (the area closest to the P 2 ) of the RF connector (L 1 &lt;L 3 ). That is, the impedance between the outer edge region P 2  and the sharp end section  65  of the shield case  60  is lower than the impedance between the outer edge region P 2  and the predefined section  200   a  of the RF connector. 
     Accordingly, when the static electricity is transmitted to the outer edge region P 2 , the static electricity is transmitted to the shield case  60  that is electronically connected to the reference potential pattern layer  75 . 
     The distance L 1  between the outer edge region P 2  and the sharp end section  65  of the shield case  60  is shorter than a distance L 2  between the outer edge region P 2  and an upper surface  210   a  (the area closest to the P 2 ) of the electronic component  210  as the second electronic component (L 1 &lt;L 2 ). That is, the impedance between the outer edge region P 2  and the sharp end section  65  of the shield case  60  is lower than the impedance between the outer edge region P 2  and the upper surface  210   a  of the electronic component  210  as the second electronic component. 
     Accordingly, when static electricity is transmitted to the outer edge region P 2 , the static electricity is transmitted to the shield case  60  that is electronically connected to the reference potential pattern layer  75 . 
     Next, by referring to  FIG. 8 , the circuit to which the RF connector  200  is connected is explained. 
     As shown in  FIG. 8 , the RF connector  200  is connected on a transmission line  520  that connects an antenna  80  and an adjustment circuit  500 , and an antenna switching control circuit  510 . In other words, the RF connector  200  is connected to the transmission line  520  through which the high frequency waves signals that are transmitted via the antenna  80  are transmitted. 
     When static electricity enters the RF connector  200  from the outside, the static electricity enters the antenna switching control circuit  510  through the transmission line  520 . In this case, there is a possibility that a switch element constituting the antenna switching control circuit  510 , etc., is destroyed. 
     In the present embodiment, the above configuration, inhibits the static electricity from entering the RF connector  200  and inhibits malfunctions of the antenna switching control circuit  510 . 
     Based on the present embodiment, with regard to the mobile phone  1 , the static electricity control for the electronic components such as the RF connector is strengthened. Accordingly, adverse effects are reduced on the electronic component or on the various configurations connected to this. 
     Moreover, according to the present embodiment, with regard to the mobile phone  1 , without adding new components, etc., the static electricity control for the electronic components such as the RF connector is strengthened. 
     Moreover, according to the present embodiment, based on the simple configuration, the static electricity control is strengthened for the electronic components such as the RF connector. 
     Moreover, according to the present embodiment, the mobile phone  1  creates a region on which the electronic components, etc., can be newly mounted by forming the through-hole  310 . That is, the mobile phone  1  can broaden the mounting area in the circuit board  70 . 
     The present invention is not limited to the above embodiment and may be implemented in various forms. For example, in the present embodiment, although the mobile phone  1  is explained as a mobile electronic device, it is not limited to this, and it may be a PHS (registered trademark; Personal Handy phone System), a PDA (Personal Digital Assistant), a portable navigation device, a notebook, etc. 
     A straight type mobile phone  1  is described above as an example embodiment. In the straight type, the housing on the operation section side and the housing on the display section side are located as one housing without having a connection section (straight type). The mobile phone  1  may be also be, for example but without limitation, a foldable type at a connection section  4 , a slide type in which in the state in which the housing on the operation section side and the housing on the display section side are overlapped, one side of the housing is slid in one direction, a turn type in which centering on an axis line along the direction of the superposition of the housing on the operation section side and the housing on the display section side, one side of the housing is rotated, and a 2-axis hinge type in which it can be opened and closed, and rotated. 
     Moreover, in the present embodiment, although the relationship of the respective distance themselves (L 1 , L 2 , L 3 ) between the outer edge region P 2  and the respective elements is defined, it is not necessary for the respective distance themselves to have the relationship described above, and so long as the respective impedances themselves between the outer edge region P 2  and the respective elements meet the relationship described above, the mobile phone provides the effects described above. 
     Moreover, in the present embodiment, although the case in which the electronic component  210  (the second electronic component) is mounted on the region AR 1  facing the inner side  310   a  of the through-hole  310  is described, it is not limited to this, and the electronic components need not be mounted on the region AR 1 . 
     For example, as shown in  FIG. 9 , the reference potential pattern layer  75  may be located on the region AR 1  facing the inner side  310   a ′ of the through-hole  310 ′. In this case, the length (height) from the second surface  71   b  to the through-hole  310 ′ is shorter than the length (height) from the second surface  71   b  to the through-hole  310 ′ in the embodiment described above. That is, the inner side  310   a ′ of the through-hole  310 ′ can be located close to the reference potential pattern layer  75  (L 5 &lt;L 4 , L 4 ′). Accordingly, the mobile phone  1  providing the effects similar to the effects in the embodiment described above can be provided.