Patent Publication Number: US-2011077063-A1

Title: Mobile terminal device and waterproof case structure

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a mobile terminal device including upper and lower cases that are slidably coupled with one another, and a waterproof case structure of the mobile terminal device. 
     2. Description of the Related Art 
     A structure, for example, a slide mobile-phone, may include upper and lower cases that are slidably coupled with one another, and a flexible substrate that extends between the cases to provide electric connection between the cases. To keep waterproof property of this structure, the sealed state of the inner spaces in the cases has to be considered. 
     Japanese Unexamined Patent Application Publication No. 2006-157465 suggests a mobile electronic device that provides smooth sliding operation, prevents water, dust, etc., from entering the device, and increases waterproof property and dustproof property. The mobile electronic device uses a waterproof rib that is formed at an edge of an opening of an upper case, and a waterproof rib that is formed at an edge of an opening of a lower case, so that the waterproof ribs prevent a foreign matter from entering the openings. 
     The pamphlet of International Publication No. 2006/095382 discloses a slide mobile-phone having a structure including upper and lower cases that have recesses in slide surfaces of the upper and lower cases, and a flexible substrate that is housed in the recesses. The recesses have slits in end surfaces of the recesses. The flexible substrate is inserted through the slits and the insertion portions of the flexible substrate are sealed (refer to  FIG. 11  in the pamphlet). 
       FIG. 8  illustrates a brief structure of such a slide mobile-phone. A lower case  100  houses a substrate  120  and a battery  110 . An upper case  200  houses a substrate  220  and a liquid crystal display (LCD)  210 . The lower case  100  and the upper case  200  are coupled with one another by a slide member  300  such that the lower case  100  and the upper case  200  can slide on one another in directions indicated by arrows  160  and  260 . The lower case  100  includes case portions  100   a  and  100   b . The lower case  100  defines an inner space by stacking the case portions  100   a  and  100   b  on one another with a ring-like packing (for example, o-ring)  130  interposed therebetween. Similarly, the upper case  200  includes case portions  200   a  and  200   b . The upper case  200  defines an inner space by stacking the case portions  200   a  and  200   b  on one another with a ring-like packing  230  interposed therebetween. 
     The slide member  300  includes a plate member  300   a  that is fixed to the case portion  100   b  of the lower case  100 , a plate member  300   c  that is fixed to the case portion  200   b  of the upper case  200 , and a coupling portion  300   b  that couples the plate members  300   a  and  300   c  with one another. The plate member  300   a  is linearly slidable relative to the plate member  300   c  via the coupling portion  300   b  within a predetermined range. 
     A flexible substrate  400  provides electric connection between the lower case  100  and the upper case  200 . One end of the flexible substrate  400  is connected with a connector  140  on the substrate  120  in the lower case  100 , and the other end thereof is connected with a connector  240  on the substrate  220  in the upper case  200 . The flexible substrate  400  extends from the connector  140 , penetrates through a wall surface that is formed in the case portion  100   b  of the lower case  100  and that is perpendicular to a surface of the substrate  120 , then extends through an opening that is formed in the slide member  300 , penetrates through a wall surface that is formed in the case portion  200   b  of the upper case  200  and that is perpendicular to a surface of the substrate  220 , and reaches the connector  240 . Gaps at penetration portions in the respective perpendicular wall surfaces are filled with packings  410 . 
     An operation unit that receives operation of a user is not particularly illustrated. In many cases, a main operation unit is provided in the lower case, and a sub operation unit is provided in the upper case. 
     SUMMARY OF THE INVENTION 
     The structure described in Japanese Unexamined Patent Application Publication No. 2006-157465 has to keep waterproof property highly reliably in a movable portion when the upper and lower cases slide. Regarding variation in precision of individual components upon mass production, it is difficult to provide high reliability. 
     In the structure of related art shown in  FIG. 8 , the packing may have a thickness of at least 1 mm, and each case may have a thickness of about 1 mm at each of positions located above and below the packing. Hence, the upper and lower cases may have a thickness of about 6 mm in total. The thickness of about 6 mm may be a serious obstruction to decrease in thickness of a mobile-phone although the arrangement of components is improved. The obstruction may affect the design of the mobile-phone. 
     Also, in a case where a rubber packing is formed by insert molding at an intermediate position of a flexible substrate, the insert molding is hardly performed while the flexible substrate is folded. It is difficult to use a flexible substrate of a folded type with a large number of pins that is included in, for example, a slide mobile-phone typically available in Japan. 
     Accordingly, it is desirable to provide a mobile terminal device including upper and lower cases and being capable of providing highly reliable waterproof property while maximally suppressing increase in thickness of the terminal. 
     According to an embodiment of the present invention, a mobile terminal device includes a first case having a first inner space in which a first substrate and an electric component are housed, the first case having a first opening in a surface of the first case facing the second case; a second case having a second inner space in which a second substrate and an electric component are housed, the second case having a second opening in a surface of the second case facing the first case; a slide member that connects the first and second cases with one another such that the second case can slide on the first case; a flexible substrate that electrically connects the first substrate in the first case and the second substrate in the second case with one another through the first and second openings; and ring-like seal members provided to surround the peripheries of the first and second openings. The first and second openings are closed with the flexible substrate with the seal members interposed therebetween. 
     The first and second openings are formed in the mutually facing surfaces of the first and second cases, and the flexible substrate is electrically connected with the substrates in the cases through the openings. Also, the openings are closed with the flexible substrate with the ring-like seal members, which are provided to surround the peripheries of the openings, interposed therebetween. The openings can be sealed while the increase in thickness of the terminal is maximally suppressed. 
     In particular, the slide member may include a first plate member fixed to the first case, and a second plate member fixed to the second case. The flexible substrate and the seal members may be pressed and pinched between the first and second plate members and the mutually facing surfaces of the first and second cases. By using the slide member which is an existing member, the openings can be more reliably sealed while the thickness of the terminal can be more reliably prevented from increasing. 
     According to another embodiment of the present invention, a waterproof case structure includes a ring-like seal member provided to surround the periphery of an opening that is formed in a surface of a case, the opening being closed with a flexible substrate with the seal member interposed therebetween; and a plate member that presses and fixes the flexible substrate to the surface of the case. 
     Other configurations and other advantages will be described later. 
     With these embodiments, the mobile terminal device that has the highly reliable waterproof property while maximally suppressing the increase in thickness of the terminal can be provided. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIGS. 1A and 1B  each illustrate an external configuration of a slide mobile-phone terminal according to an embodiment of the present invention; 
         FIG. 2  briefly illustrates a first configuration example of the mobile-phone terminal in  FIGS. 1A and 1B ; 
         FIG. 3  is an exploded perspective view showing a specific configuration for sealing an opening in a case portion in  FIG. 2  while part of the configuration is not illustrated; 
         FIG. 4  briefly illustrates a second configuration example of the mobile-phone terminal in  FIGS. 1A and 1B ; 
         FIG. 5  is an exploded perspective view showing a slide member of the configuration example in  FIG. 4 ; 
         FIG. 6  briefly illustrates a third configuration example of the mobile-phone terminal in  FIGS. 1A and 1B ; 
         FIG. 7  illustrates an external configuration of a flexible substrate in  FIG. 6 ; and 
         FIG. 8  illustrates a brief configuration of a slide mobile-phone of related art. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Preferred embodiments of the present invention will be described below in detail with reference to the attached drawings. 
       FIGS. 1A and 1B  each illustrate an external configuration of a slide mobile-phone terminal device according to an embodiment of the present invention. In the specification, the terminal device may be merely referred to as terminal. 
       FIG. 1A  illustrates a closed state of upper and lower cases.  FIG. 1B  illustrates an open state of the upper and lower cases. The mobile-phone terminal includes a lower case  10  (first case) and an upper case  20  (second case). The upper case  20  is coupled with the lower case  10  such that the upper case  20  can linearly slide on the lower case  10 . The upper case  20  includes a LCD  21  serving as a display unit (display device), and a sub operation unit  25 . The lower case  10  includes a main operation unit  17  including numeric keypads and arranged at a position at which the main operation unit  17  is hidden by the upper case  20  in the closed state and exposed in the open state. Though not shown, a speaker and a microphone are arranged at predetermined positions in the upper and lower cases. 
       FIG. 2  briefly illustrates a first configuration example of the mobile-phone terminal in  FIGS. 1A and 1B . This drawing is a cross-sectional view taken along a plane perpendicular to a display screen to extend in a longitudinal direction of the upper and lower cases in the closed state. To clearly show the details,  FIG. 2  does not correspond to the actual scale of the terminal. 
     The lower case  10  has a first inner space in which a substrate  12  with an electric component mounted thereon, and a battery  11  are housed. The upper case  20  has a second inner space in which a substrate  22  with another electric component mounted thereon, and the LCD  21  are housed. The lower and upper cases  10  and  20  are coupled with one another by a slide member (slide unit)  30  such that the lower and upper cases  10  and  20  can be linearly slidable on one another (in directions indicated by arrows  16  and  26 ). The lower case  10  includes case portions  10   a  and  10   b . The lower case  10  defines the inner space by stacking the case portions  10   a  and  10   b  on one another with a ring-like packing (for example, o-ring)  13  interposed therebetween. Similarly, the upper case  20  includes case portions  20   a  and  20   b . The upper case  20  defines the inner space by stacking the case portions  20   a  and  20   b  on one another with a ring-like packing  23  interposed therebetween. 
     The slide member  30  includes a plate member  30   a  (first plate member) that is fixed to the case portion  10   b  of the lower case  10 , a plate member  30   c  (second plate member) that is fixed to the case portion  20   b  of the upper case  20 , and a coupling portion  30   b  that couples the plate members  30   a  and  30   c  with one another. The plate members  30   a  and  30   c  respectively have openings  47 . The plate member  30   a  is linearly slidable relative to the plate member  30   c  via the coupling portion  30   b  within a predetermined range. Since the structure of the slide member  30  is an existing structure, the detailed description of the structure will be omitted. 
     A flexible substrate  40  is formed of a flexible member including a conductor arranged therein and provides electric connection between the lower case  10  and the upper case  20 . One end of the flexible substrate  40  is connected with a connector  14  on the substrate  12  in the lower case  10 , and the other end thereof is connected with a connector  24  on the substrate  22  in the upper case  20 . 
     The lower and upper cases  10  and  20  have first and second openings  43  that are formed in mutually facing surfaces of the lower and upper cases  10  and  20  and communicate with the inner spaces. The flexible substrate  40  is electrically connected with the first and second substrates  12  and  22  through the first and second openings  43 . Also, ring-like gaskets  41  (thin-plate-like packings serving as seal members) are respectively provided to surround the peripheries of the first and second openings  43 . The first and second openings  43  are closed with the flexible substrate  40  with the gaskets  41  interposed therebetween. By desirable fixing means, the flexible substrate  40  and the gaskets  41  are pressed and pinched respectively between the first and second plate members  30   a  and  30   c , and the mutually facing surfaces of the lower and upper cases  10  and  20 . The fixing means may be, for example, a screw, a bolt and a nut, or a structure using a spring force. 
     An operation unit that receives operation of a user is not particularly illustrated. In many cases, a main operation unit is provided in the lower case  10 , and a sub operation unit is provided in the upper case  20 . 
       FIG. 3  is an exploded perspective view showing a specific configuration for sealing the opening  43  in the case portion  10   b  in  FIG. 2  while part of the configuration is not illustrated. This drawing shows a primary portion of a waterproof case structure. The opening  43  formed in a plate surface of the case portion  10   b  is used to allow a terminal portion  40   a  of the flexible substrate  40  to be connected with the connector  14  in the case. The gasket  41  and the flexible substrate  40  are pressed and fixed to the case portion  10   b  by the plate member  30   a  of the slide member  30  such that the opening  43  is closed with a surface of the flexible substrate  40  with the ring-like gasket  41 , which is arranged to surround the periphery of the opening  43 , interposed between the flexible substrate  40  and the plate member  30   a . In this example, pressing and fixing are performed by inserting screws through screw holes  31  formed in the plate member  30   a  and screwing the screws into corresponding thread grooves  15  formed in the case portion  10   b . The fixing method is not limited to screwing. Means for coupling the slide member  30  with the lower and upper cases  10  and  20  may use a configuration that is originally provided. 
     By using the slide member  30 , the flexible substrate  40  that provides electric connection between the lower and upper cases  10  and  20  closes the openings  43  of the lower and upper cases  10  and  20  with the gaskets  41  interposed therebetween. Hence, the openings can be sealed in a watertight manner. 
       FIG. 4  briefly illustrates a second configuration example of the mobile-phone terminal in  FIGS. 1A and 1B . This drawing is a cross-sectional view similar to  FIG. 2 . Components similar to those in  FIG. 2  will refer like reference numerals and redundant description will be omitted. 
     In the second configuration example, a slide member  30  includes a first plate member  30   a  that is fixed to a lower case  10 , and a second plate member  30   c  that is fixed to an upper case  20 . The second plate member  30   c  also serves as a case surface of the upper case  20 . The plate member  30   a  has an opening  47 . A flexible substrate  40  is electrically connected with a connector  14  of a substrate  12  through the opening  47 . The plate member  30   c  has an opening  43 . The flexible substrate  40  is electrically connected with a connector  24  of a substrate  22  through the opening  43 . Also, in this configuration example, a waterproof adhesive sheet  46  is used as a seal member. A third plate member  48  faces the opening  43  of the plate member  30   c . The third plate member  48  presses and fixes an end portion of the flexible substrate  40  to the plate member  30   c  with the waterproof adhesive sheet  46  interposed therebetween. Although this fixing means is not particularly limited, for example, screwing as described above may be used. 
     In this example, the plate member of the slide member also serves as the case surface of the upper case. Alternatively, the plate member of the slide member may serve as a case surface of the lower case. Still alternatively, the plate members of the slide member may serve as case surfaces of both the upper and lower cases. In any of the configuration examples, the seal member may be a gasket or a waterproof adhesive sheet. 
       FIG. 5  is an exploded perspective view showing the slide member  30  of the configuration example in  FIG. 4 . The illustration of the third plate member  48  is omitted. 
       FIG. 6  briefly illustrates a third configuration example of the mobile-phone terminal in  FIGS. 1A and 1B . Components similar to those in  FIGS. 2 and 4  will refer like reference numerals and redundant description will be omitted. 
     In this configuration, two openings  43   a  and  43   b  are provided in a lower case  10 . A flexible substrate  44  has a contact portion at one end thereof that is exposed through the opening  43   a , and a contact portion at the other end thereof that is exposed through the opening  43   b . The flexible substrate  44  is folded into two sections, and has a contact portion provided substantially at a center portion thereof that is exposed through an opening  43  in an upper case  20 . In this example, waterproof adhesive sheets  46  are used for the openings  43   a  and  43   b  in the lower case  10 , whereas a gasket  41  is used for the opening  43  in the upper case  20 . As described above, the seal member may be any of the gasket  41  and the waterproof adhesive sheet  46 , and may be even other members. 
     The flexible substrate  44  extends between the lower and upper cases  10  and  20  in a path around the slide member  30 . In this configuration example, or in any of the above-described configuration examples, the flexible substrate  44  may extend through the opening in the slide member or extend in a path around the slide member when the flexible substrate  44  extends between the lower case  10  and the upper case  20 . 
       FIG. 7  illustrates an external configuration of the flexible substrate  44  in  FIG. 6 . The flexible substrate  44  has a contact portion at one end  44   a  thereof, and a contact portion at the other end  44   b  thereof. The contact portions at the one end  44   a  and the other end  44   b  are electrically connected with connectors. Also, the flexible substrate  44  has a contact portion at a center portion  44   c  thereof. The contact portion at the center portion  44   c  is electrically conductive with the contact portions at the one end  44   a  and the other end  44   b.    
     In this embodiment, the waterproof structure relating to the flexible substrate basically has the following configuration. 
     (1) The openings are formed in the mutually facing case surfaces of the upper and lower cases. The connectors are exposed through the openings and used for electric connection between the connectors and the flexible substrate. 
     (2) The ring-like seal members are provided to surround the peripheries of the openings, and the openings are sealed with the flexible substrate with the seal members interposed therebetween. 
     (3) The plate members of the slide member and the case surfaces around the openings press and pinch the flexible substrate together with the seal members. 
     With this configuration, a proper holding pressure that provides adhesiveness of the seal members can be kept, the seal members can be prevented from peeled or dropped, and the connectors can be prevented from being detached. 
     Also, with this structure, a waterproof portion is not a movable portion. Thus, the structure has high reliable waterproof property as compared with a movable structure. 
     Also, the waterproof structure is accommodated within an approximate height of the connectors. A dimensional loss in a thickness direction when the waterproof structure is provided is almost negligible. Further, the slide unit also serves as a connector detachment prevention structure and a gasket pressure structure. The reliability is further increased with the structure is still simple. Accordingly, with this structure, a slide mobile terminal can have highly reliable waterproof structure while providing a thin structure. 
     While the preferred embodiments have been described above, various modifications and changes may be included in the present invention, in addition to the aforementioned configurations. For example, the description only has focused on the mobile-phone terminal, however, the present invention may be applied to any mobile device including upper and lower cases. 
     The present application contains subject matter related to that disclosed in Japanese Priority Patent Application JP 2009-222665 filed in the Japan Patent Office on Sep. 28, 2009, the entire content of which is hereby incorporated by reference. 
     It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and alterations may occur depending on design requirements and other factors insofar as they are within the scope of the appended claims or the equivalents thereof.