JP2007266895A - Portable electronic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a portable electronic apparatus which discharges static electricity infiltrating through a housing opening without greatly causing an assembling man-hour increase or a cost rise. <P>SOLUTION: A portable telephone 1 comprises a circuit board 21, a conductive shield case 23, a key board 25 having a key switch 55, and a key sheet 61 having an operating key 10 at a position opposite to the key switch 55 on an opposed elastic sheet 62 so as to cover a part or the whole of the key board 25 in a housing 2 constituting a telephone, and the operating key 10 is in an opening 12 formed in the housing 2. The key board 25 has a hole 57, and the elastic sheet 62 has a projection 66 inserted in the hole 57 with a through-hole 67 piercing the projection 66 from the sheet 62 surface. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a portable electronic device such as a mobile phone having operation keys and a PDA (Personal Digital Assistant).

  2. Description of the Related Art Conventionally, portable electronic devices such as mobile phones and PDAs (Personal Digital Assistants) have a plurality of electronic components 83 such as IC packages, capacitors, resistors, etc. mounted on one surface 81a as shown in FIGS. The first circuit board 81, the shield case 85 disposed on one surface 81a of the first circuit board 81 so as to cover the electronic component 83, and the liquid crystal display 90 and the key switch 91 are disposed on the one surface 92a. The second circuit board 92, a key sheet (not shown) having an operation key 95 on an elastic resin sheet, and an antenna 93 are housed in a housing 91 including a front case 87 and a rear case 89. ing.

  The front case 87 is provided with a plurality of openings 87a and 87b so that the display screen of the liquid crystal display can be visually recognized from one opening 87a, and the operation key is provided in the other opening 87b. 95 is arranged and configured to be operable.

  The second circuit board 92 and the antenna 93 are electrically connected to the first circuit board 81, respectively, and arranged on the surface 81a of the circuit board 81 so as to be divided into a predetermined number of electronic components 83. A provided reference potential layer (ground pattern layer) 82 is formed. The shield case 85 has conductivity and includes a partition wall (not shown) that surrounds the electronic component 83 partitioned as described above. That is, in a state where the shield case 85 is fixed to one surface 81 a of the circuit board 81, the partition wall portion of the shield case 85 and the reference potential layer 82 of the circuit board 81 are electrically connected.

The shield case 85 is formed so as to cover substantially the entire surface 81a of the circuit board 81, and is fixed to the circuit board 81 by screws or the like. The circuit board 81 and the shield case 85 may be fixed by soldering in addition to screwing or the like.
JP-A-4-215500

  By the way, since the housing 91 has the opening 87b, there is a problem that static electricity enters into the housing 91 and adversely affects electric components and electronic components provided in the housing 91. Particularly in recent years, with the reduction in thickness of portable electronic devices, it is required to reduce the size and thickness of each component, and the thickness of the elastic resin sheet forming the key sheet is also reduced. As a result, static electricity that has entered through the housing opening 87b passes through the elastic resin sheet and falls to a conductor close to the housing opening 87b, which adversely affects the portable electronic device.

  Specifically, as shown in a schematic cross-sectional view of the portable electronic device in FIG. 9A, the static electricity that has entered through the housing opening 87 b so far travels along the elastic resin sheet surface 96 a of the key sheet 97 to the first circuit board. 81, and designed to prevent static electricity from flowing into the key switch 91 and the like by allowing it to escape onto the reference potential layer 82 formed on the first circuit board 81. As described above, As a result of the thinning of the elastic resin sheet 16 accompanying the reduction in thickness of the portable electronic device, as shown in FIG. 9B, static electricity that has entered through the housing opening 87b causes the elastic resin sheet surface 96a of the key sheet 97 to enter. Instead of being transmitted, it passes through the elastic resin sheet 16 and falls to the key switch 91 and other electric / electronic components arranged in the vicinity of the opening of the casing, causing problems.

  Therefore, a conductive sheet is interposed between the casing 91 and the key sheet 97, or the inner surface of the casing is covered with a conductive film, so that static electricity is applied to the second circuit board 92, the first circuit board 81, or the shield case 85. In this case, it is necessary to provide a conductive sheet as a separate part, or to form a conductive film on the inner surface of the housing as a separate process, which is inexpensively manufactured by increasing the number of assembly steps and increasing costs. There was a problem that it was not possible.

  The present invention has been made in view of the above-described circumstances, and provides a portable electronic device capable of releasing static electricity that has entered through a housing opening without causing an increase in assembly man-hours and a significant increase in cost. The purpose is that.

  Therefore, the present invention has an electronic component mounted on one surface and a circuit board on which a reference potential portion surrounding the mounting region of the electronic component is disposed, and is disposed in contact with the reference potential layer, A conductive shield case placed on the circuit board so as to cover the electronic component, a key board placed on the shield case and provided with a key switch, and part or all of the key board A key sheet provided with an operation key at a position facing the key switch of an elastic sheet disposed so as to cover the key sheet is provided in the housing, and the operation key is provided in an opening formed in the housing In the portable electronic device, the key board has a hole, and the elastic sheet has a protrusion inserted into the hole, and has a through-hole penetrating the protrusion from the housing surface side. With features That.

  Further, the present invention is characterized in that the protruding portion is brought into contact with the shield case.

  Furthermore, the present invention is characterized in that a boss protruding from the inner surface of the housing is fitted into the through hole.

  The present invention is characterized in that the boss is brought into contact with the shield case.

  According to the present invention, it is possible to release static electricity that has entered through a housing opening constituting a portable electronic device to a reference potential layer provided in the housing without causing an increase in assembly man-hours and a significant cost increase. It is possible to prevent adverse effects on the electronic components and electrical components forming the electronic device.

  1 to 6 show one embodiment according to the present invention, and the embodiment described here is a case where the present invention is applied to a mobile phone.

  As shown in FIG. 1, a mobile phone (portable electronic device) 1 according to this embodiment includes a first housing 2 and a second body that can be overlapped in the thickness direction of the first housing 2. A housing 3 and a hinge portion 5 that foldably couples the two housings 2 and 3 to each other are provided. In addition, the hinge part 5 is distribute | arranged so that each base end part 2a, 3a of the two housing | casing 2 and 3 may be connected.

  Inside the second casing 3, there are a display unit 7 such as an LCD (Liquid Crystal Display), an organic EL (Electro Luminescence) display, an inorganic EL display, etc., and a speaker unit for a call. 9 is provided. The display surface 7a of the display unit 7 is exposed on the facing surface 3c side of the second housing 3 facing the first housing 2 in a state where the two housings 2 and 3 are overlapped with each other. The speaker unit 9 is disposed on the distal end portion 3b of the second housing 3 located on the opposite side to the base end portion 3a, and from the facing surface 3c of the second housing 3 to the second housing 3. It is exposed to the outside through an opening 3d that penetrates the internal space.

  Inside the first housing 2 are a key operation unit 11 having a plurality of operation keys 10 that can be pressed down variously such as numeric keys, cursor keys, function keys such as a call key and a call end key, and a telephone for a call. A microphone unit 15 is provided. Each operation key 10 of the key operation unit 11 is an opening formed on the facing surface 2c of the first casing 2 that faces the second casing 3 in a state where the two casings 2 and 3 are overlapped with each other. 12 is exposed outward.

  The microphone portion 15 is disposed on the distal end portion 2b of the first housing 2 located on the side opposite to the base end portion 2a, and from the facing surface 2c of the first housing 2 to the first housing 2. It is exposed to the outside through an opening 2d that penetrates the internal space.

  The first housing 2 includes a front case 17 constituting the facing surface 2 c side of the first housing 2 and a rear case 19 constituting the outer surface 2 f side of the first housing 2. The front case 17 and the rear case 19 can be coupled to each other in the thickness direction of the first housing 2.

  As shown in FIG. 2, the first housing 2 includes a circuit board 21, a shield case 23, a key board 25, and the above-described circuit board from the inner surface 19a side of the rear case 19 located on the opposite side of the outer surface 2f. A key sheet 61 having a plurality of operation keys 10 constituting the key operation unit 11 is arranged in an overlapping manner. In addition, an antenna 27 for wireless communication is accommodated on the distal end portion 2b side in the first housing 2. That is, the antenna 27 is arranged in the vicinity of the circuit board 21, the shield case 23, and the flexible board 25.

  A plurality of electronic components are mounted on one surface 21 a of the circuit board 21 facing the shield case 23. The electronic components include a high frequency block 31, a power supply IC 33, a memory 35, a CPU 37, and the like.

  Here, the high frequency block 31 is electrically connected to the antenna 27 via the circuit board 21 and, as shown in FIG. 3, between the antenna 27 and another telephone set via the communication network (not shown). It makes a telephone call and transmits / receives various information such as e-mails and Internet home pages to / from other terminal devices and servers (not shown). Further, the power supply IC 33 controls charging and discharging of the battery 39 provided in the mobile phone 1. Further, the memory 35 stores various information such as characters, symbols, images, and various functions of the mobile phone 1.

  The CPU 37 controls operations of the display unit 7, the speaker unit 9, the microphone unit 15, the high frequency block 31, the power supply IC 33, the memory 35, and the like. That is, the CPU 37 plays a role of, for example, outputting voice information input from the microphone unit 15 to the high frequency block 31 or outputting voice information input from the high frequency block 31 to the speaker unit 9 when making a call. For example, the CPU 37 stores various information received by the high frequency block 31 in the memory 35 and plays a role of displaying various information on the display unit 7 based on the operation of the key operation unit 11.

  Further, as shown in FIGS. 2 and 4, a reference potential layer (reference potential portion) 41 as a ground pattern surrounding the plurality of electronic components described above is disposed on one surface 21 a of the circuit board 21. .

  The reference potential layer 41 is formed so as to partition a mounting area for a plurality of electronic components for each electronic component that constitutes a predetermined function. That is, the first mounting area S1 in which the high frequency block 31 is mounted, the second mounting area S2 in which the power supply IC 33 is mounted, the third mounting area S3 in which the memory 35 and the CPU 37 are mounted, and other capacitors and resistors. A plurality of fourth mounting regions S4 on which the electronic components 32 are mounted are individually partitioned by the reference potential layer 41. The plurality of mounting areas S <b> 1 to S <b> 4 divided in this way are each positioned on the periphery of one surface 21 a of the circuit board 21.

  As shown in FIGS. 2 and 5, the shield case 23 is a substantially plate-shaped ceiling that faces one surface 21 a of the circuit board 21 and covers most of the surface 21 a of the circuit board 21 as shown in FIGS. It is composed of a plate portion 43, a side wall portion (partition wall portion) 45 and a rib (partition wall portion) 47 erected on the back surface 43 b of the top plate portion 43 so as to cover the plurality of electronic components described above. It is fixed to one surface 21a of the circuit board 21 by screwing.

  That is, the side wall portion 45 protrudes from the entire periphery of the back surface 43 b of the top plate portion 43, and is configured to contact the reference potential layer 41 formed on the periphery of one surface 21 a of the circuit board 21. Further, the rib 47 is configured to abut on a reference potential layer 41 formed between the mounting regions S1 to S4 of the circuit board 21.

  Therefore, in a state where the shield case 23 is fixed to the one surface 21 a of the circuit board 21, the shield case 23 covers substantially the entire surface 21 a of the circuit board 21. Can be improved.

  Further, since the shield case 23 is brought into contact with the reference potential layer 41 and a plurality of electronic components can be divided and arranged in spaces corresponding to the mounting areas S1 to S4, the shielding case 23 is arranged in the mounting areas S1 to S4. Each corresponding space can be shielded.

  The shield case 23 configured as described above can be formed of metal. For example, the top plate portion 43 is formed of a metal plate and the side wall portions 45 and the ribs 47 are formed of resin. After bonding through an adhesive or the like, the side wall portion 45 and the rib 47 may be coated with a conductive film to provide conductivity. The shield case 23 is formed by, for example, integrally forming the top plate portion 43, the side wall portions 45, and the ribs 47 with a resin, and covering the surface with a conductive film to provide conductivity. It doesn't matter. In this way, when part or all of the shield case 23 is formed of resin, the mobile phone 1 can be effectively reduced in weight.

  2, 5, and 6, the key operation unit 11 includes a key sheet 61 having the plurality of operation keys 10 described above on the elastic resin sheet 62, and a key substrate 25 having a plurality of key switches 55. It is composed of

  The key substrate 25 is a switch sheet that is formed in a sheet shape and has flexibility, and is arranged over the surface 43 a of the top plate portion 43. On the surface 51 a of the key substrate 25, the same number of dome-shaped key switches 55 as the operation keys 10 are formed at positions facing the operation keys 10, and are electrically connected to the circuit board 21 described above.

  As described above, the key sheet 61 includes the flexible elastic resin sheet 62 and the operation key 10, and the elastic resin sheet 62 is arranged on each surface 63 a with a predetermined interval between the operation keys. 10 is formed in a substantially plate-like flat plate portion 63 and the other surface 63b of the flat plate portion 63 opposite to the one surface 63a, and protrudes from a position facing each operation key 10. And a wall portion 65 formed so as to protrude from the convex portion 64 from the other surface 63b opposite to the one surface 63a.

  Further, the other surface 63b of the elastic resin sheet 62 has a columnar protruding portion 66 that is slightly higher than the height H of the wall portion 65, and has a stepped portion 66a at its tip. The elastic resin sheet 62 is formed with a through-hole 67 that opens from one surface 63a through the protrusion 66 to the front end surface of the protrusion.

  A boss 17a formed so as to protrude from the inner surface of the front case 17 is fitted into the through hole 67. At this time, each key sheet 61 is inserted into the opening 12 formed in the front case 17. An operation key 10 is arranged so as to be exposed to the outside. That is, the through hole 67 of the elastic resin sheet 62 functions as a boss hole of the boss 17 a formed in the front case 17 and can position the key sheet 61 with respect to the front case 17. Therefore, since the boss 17a of the front case 17 is fitted in the through hole 67 of the elastic resin sheet 62 in advance when the mobile phone 1 is assembled, it can be integrated with the positioning of the key sheet 61. Can increase the sex.

  Further, when the front case 17 and the rear case 19 are integrated, the wall portion 65 of the elastic resin sheet 62 abuts on the key substrate 25 and forms a space between the flat plate portion 63 and the key substrate 25. The convex portion 64 of the flat plate portion 63 is arranged to face the key switch 55 of the key substrate 25 with a slight gap or to be arranged in contact therewith. When the operation key 10 is pressed toward the surface 43 a of the top plate portion 43, the key substrate 25 is supported by the top plate portion 43 of the shield case 23, so that the convex portion that faces the operation key 10. The key switch 55 is pressed by 64 to be turned on.

  Further, the key substrate 25 is provided with a hole 57 at a position facing the protrusion 66 of the key sheet 61 when the front case 17 and the rear case 19 are integrated, and the elastic resin sheet is placed in the hole 57. A stepped portion 66 a formed at the tip of the projecting portion 62 is inserted, and the tip of the projecting portion comes into contact with the top plate portion 43 of the shield case 23. That is, the through hole 67 of the elastic resin sheet 62 communicates with the top plate portion 43 of the shield case 23.

  For this reason, static electricity that enters through the gap between the opening 12 of the front case 17 and the operation key 10 is conductive that is electrically connected to the reference potential layer 41 through the through hole 67 from one surface 63a of the flat plate portion 63. Can be released to the shield case 23, and reduce the occurrence of problems due to static electricity jumping into the key switch 55 and other electronic components located below the opening 12 through the flat plate portion 63 of the elastic resin sheet 62. Can do.

  In particular, in order to obtain such an effect, it is preferable to provide a through hole 67 formed in the elastic resin sheet 62 in the vicinity of the opening 12 of the front case 17, for example, a plurality of operation keys 10 constituting a plurality of numeric keys. If the through hole 67 is positioned below the front case wall 2e that partitions the space, or if the through hole 67 is positioned below the front case wall 2g that partitions the cursor key and each function key good.

  Further, in order to make it easy for the static electricity to escape to the shield case 23, it is preferable to configure the tip of the protruding portion forming the through hole 67 to contact the top plate portion 43 of the shield case 23. Thus, static electricity transmitted through the inner surface of the through hole can be surely released to the shield case 23.

  Further, the boss 17a formed on the front case 17 is preferably formed so as to contact the top plate portion 43 of the shield case 23 when the front case 17 and the rear case 19 are integrated. By doing so, even when the front case wall portions 2e and 2g are pressed together when the operation key 10 is pressed, the deformation of the front case 17 can be suppressed and the operation key 10 can be reliably operated. At the same time, the operation key 10 can be prevented from entering the front case 17, and the strength of the housing 2 forming the mobile phone can be increased.

  In addition, according to the cellular phone 1, intrusion of noise from the outside can be prevented by the shield case 23 covering substantially the entire surface 21a of the circuit board 21, and radiation is caused by driving each electronic component. It is possible to reduce the adverse effect of the electromagnetic waves exerted on other electronic components and other electronic / electronic components provided in the first housing 2.

  Furthermore, since the top plate portion 43 of the shield case 23 serves as a support plate for supporting the key operation unit 11, the top plate portion 43 has sufficient strength against the pressing operation of the operation keys 10 of the key operation unit 11. Can be secured. Then, by supporting the key substrate 25 having the key switch 55 by the top plate portion 43, the cellular phone 1 can be thinned.

  Further, the switch sheet 51 does not need to be configured by a flexible substrate having flexibility, and may be configured by a circuit substrate having no flexibility, for example.

  Furthermore, in the above-described embodiment, the mobile phone 1 including the two casings 2 and 3 connected to each other by the hinge portion 5 has been described. However, the present invention is not limited to this, and for example, the mobile phone 1 includes a single casing. It may be a mobile phone.

  Further, the present invention is not limited to a mobile phone, and can be applied to a portable wireless device having at least a wireless communication function. For example, a PDA or a notebook personal computer having a communication function may be used.

  As mentioned above, although embodiment of this invention was explained in full detail with reference to drawings, the concrete structure is not restricted to this embodiment, The design change etc. of the range which does not deviate from the summary of this invention are included.

It is an external appearance perspective view which shows the whole portable telephone of this invention. It is a disassembled perspective view which shows the structure of the 1st housing | casing in the mobile telephone of this invention. It is a block diagram which shows the structure of the mobile telephone of FIG. FIG. 2 is a schematic plan view showing a circuit board in a first housing in the mobile phone of FIG. 1. It is XX sectional drawing in the mobile telephone of FIG. It is a disassembled perspective view which shows the key operation part in the mobile telephone of FIG. It is a disassembled perspective view which shows an example of the conventional portable radio. FIG. 8 is an exploded perspective view showing a circuit board and a shield case arranged inside the housing in the portable wireless device of FIG. 7. FIGS. 8A and 8B are cross-sectional views for explaining an intrusion state of static electricity in the portable wireless device of FIG.

Explanation of symbols

1 Mobile phone (mobile electronic device)
2 First housing 2c Opposing surface 2e Side surface 2f Outer surface 10 Operation key 11 Key operation unit 12 Opening 21 Circuit board 21a One surface 21b Other surface 23 Shield case 25 Key substrate 27 Antenna 31 High frequency block 32 Other electronic components 33 Power supply IC
35 Memory 37 CPU
41 Reference potential layer 43 Top plate part 43a Surface 45 Side wall part 47 Rib 51 Switch sheet 55 Key switch 57 Hole 61 Key sheet 62 Elastic resin sheet 63 Flat plate part 64 Projection part 65 Wall part 66 Projection part 67 Through-hole S1-S4 Mounting area

Claims (4)

An electronic component is mounted on one surface, a circuit board on which a reference potential portion surrounding the electronic component mounting region is disposed, and abuttingly disposed on the reference potential layer so as to cover the electronic component Conductive shield case placed over the circuit board, a key board placed over the shield case and provided with a key switch, and opposed to cover part or all of the key board A portable electronic device comprising a key sheet provided with an operation key at a position facing the key switch of the elastic sheet, and the operation key provided in an opening formed in the case. The key board has a hole, and the elastic sheet has a protrusion inserted into the hole and has a through-hole penetrating the protrusion from the housing surface side. Electronics. The portable electronic device according to claim 1, wherein the protruding portion is in contact with the shield case. The portable electronic device according to claim 1, further comprising: a boss protruding from the inner surface of the housing, wherein the boss is fitted into the through hole. The portable electronic device according to claim 3, wherein the boss is in contact with the shield case.

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