JP2006066157A - Key input device structure and portable communication device having structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a key input device structure for preventing the occurrence of relative position shift of a key sheet having a key button when a portable communication device receives external shock by fall-down or the like. <P>SOLUTION: On the key input device part 3 of the portable communication device, protrusions 7 having sharp pointed end are mounted on and fixed to a printed board 6, and the sharp pointed end of the protrusions 7 is made to penetrate through the sheet 4 of a metal dome and thrust a rubber sheet 3b. A plurality of key buttons 3a exposed outward from openings 1b of a case, pressed down at operation are integrally arranged on the rubber sheet 3b. When a force, elastically deforming the rubber sheet 3b, generated when the device receives external shock like fall-down, is added, the elastic deformation is restricted by the thrusted protrusions 7. Consequently, such a situation that the key buttons 3a are made to creep into the case from the openings 1b and it becomes impossible to operate, is prevented, and the reliability of the input device part 3 against the external shock like fall-down is improved. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a portable communication device, and more particularly to a key input device structure that regulates a positional shift of a key input device portion caused by an external impact applied to the portable communication device, and a portable communication device having this structure.

  In recent years, various manufacturers have entered the market for portable communication devices, especially mobile phones, and a wide variety of terminals have been introduced to the market, and portable information terminal devices that can use not only calls but also the Internet and e-mail, etc. As the market is expanding. In such a portable communication device, the key input unit is an especially important function.

  On the other hand, since there is a risk that a user may accidentally drop a portable communication device when using or carrying it, the key input device, which is an important function, is required to have a structure that can sufficiently withstand an impact such as dropping. The

  Here, as a conventional portable communication device, a mobile phone is exemplified, and a key input device structure thereof will be described. FIG. 1 shows an external appearance of a general mobile phone in a perspective view, and FIG. 11 shows a cross-sectional view of a conventional key input device structure as a cross section taken along line AA of FIG.

  As shown in FIG. 1, a typical mobile phone is composed of a pair of upper and lower cases 1 and 2 made of resin or the like. On the upper surface side of the upper case 1, there is provided a display device portion having a liquid crystal and a key input device portion 3 in which number keys and the like used when the mobile phone is used are arranged. As shown in FIG. 11, the key input device unit 3 is mounted with a rubber sheet 13 b in which a plurality of key buttons 13 a are formed in a casing having an upper case 1 and a lower case 2, and a printed circuit board 16.

  A plurality of key buttons 13a integrated by adhesion to a rubber sheet 13b formed of elastic rubber are respectively provided through the opening 11b on the upper surface of the upper case 1 at predetermined positions. The rubber sheet 13 b has an outer shape held by ribs 11 a formed integrally with the upper case 1, and the printed circuit board 16 and the upper case 1 supported by a plurality of support portions 12 a formed integrally with the lower case 2. It is mounted between.

  An electrical component 16 a is mounted on the lower surface of the printed circuit board 16, while a plurality of conductive portions 16 b formed with circuits are formed on the upper surface of the printed circuit board 16. Further, an extremely thin sheet 14 made of a material such as a polyester film having an adhesive applied to the entire surface is provided so as to cover each of the plurality of conductive portions 16b. A plate-shaped dome 15 that forms a spherical surface with a conductive material such as an ultrathin metal plate that is adhesively fixed is attached to and fixed on the sheet 14. When the user performs a key operation, the convex portion 13c of the rubber sheet 13b elastically deforms the dome 15 and conducts the conductive portion 16b of the printed circuit board 16, thereby detecting a key input.

  Such a configuration of the conventional key input device section 3 does not have a structure that can sufficiently withstand an external impact caused by dropping or the like.

  On the other hand, in a conventional portable communication device, a prior art having a structure in which measures against external impacts are taken is disclosed in Patent Document 1 shown below.

Japanese Unexamined Patent Publication No. 2002-341995 (page 3-4, FIG. 3-4) FIG. 13 shows a cross-sectional view of the key input device portion disclosed in Patent Document 1. In FIG. A casing 21 having an upper case 21a and a lower case 21b incorporates a key sheet 23 having a plurality of key buttons 22, a metal dome sheet 25 having a metal dome 25a, and a printed circuit board 26. The key sheet 23 is formed with a plurality of protrusions 24 that support the upper case 21a from the inside. When an external impact is applied to the upper case 21a, the upper case 21a is supported by a plurality of protrusions 24 to prevent the upper case 21a from being deformed, and the key button 22 is not pressed by the upper case 21a.

  In the conventional key input device structure of the portable communication device described above, the conventional key input device unit 3 shown in FIG. 11 does not have a structure that can withstand external shocks. is there.

  That is, as shown in FIG. 12, when subjected to an external impact such as dropping, the rubber sheet 13b formed of elastic rubber is elastically deformed so as to slide on the surface of the sheet. For this reason, the key button 13a integrated with the rubber sheet 13b is displaced, and enters the inside of the casing of the upper case 1 from the opening 11b, thereby causing a problem that the key operation cannot be performed.

  Further, in the key input device portion in Patent Document 1 shown in FIG. 13, a plurality of protrusions 24 that support the upper case 21 a are provided on the key sheet 23. However, the key sheet 23 is originally made of a flexible material (elastic rubber or resin molded product) so as to accurately transmit the pressing force of the key button 22 to the metal dome 25a. Therefore, it is considered that the protrusion 24 provided on the key sheet 23 made of such a flexible material is insufficient for exerting a force sufficient to support the deformation of the upper case 21a. There is a problem that the shape becomes large and the mass of the device increases. Two-color molding is also conceivable in which the key sheet 23 is a resin molded product and only the portion of the protrusion 24 has a high hardness. However, in this case, there is a problem that an increase in manufacturing cost cannot be avoided.

  An object of the present invention is to solve the above-described conventional problems, and in a portable communication device such as a cellular phone, the key sheet constituting the key button is relative to the casing even when subjected to an external impact such as dropping. It is an object of the present invention to provide a key input device structure with improved reliability against an impact such as a drop by regulating the position so as not to be displaced.

The key input device structure of the present invention has an opening for mounting a key sheet and a printed circuit board on which a plurality of key buttons are formed in a casing having an upper case and a lower case, and exposing the operation portions of the plurality of key buttons. In the key input device structure of the portable communication device formed in the upper case,
A restricting member that restricts a relative positional shift of the key sheet with respect to the opening is protruded from a fixed portion adjacent to the key sheet toward the key sheet.

  In this key input device structure, the restricting member is a protrusion having a sharp tip, the protrusion is mounted and fixed on the printed board, and the sharp tip is between the key sheet and the printed board. It is characterized in that it is inserted into the key sheet through a cover sheet, and the mounting and fixing of the projection to the printed circuit board may be by soldering or by adhesion with an adhesive, and further, The tip of the protrusion may have a conical aperture shape.

  Further, in this key input device structure, the restricting member is a protrusion having a sharp tip, and the protrusion adheres to a surface of the cover sheet between the key sheet and the printed board facing the printed board. The sharp tip may be fixed and inserted into the key sheet through the cover sheet.

According to another key input device structure of the present invention, a key sheet and a printed board on which a plurality of key buttons are formed are mounted in a casing having an upper case and a lower case, and the key sheet and the printed board are further disposed between the key sheet and the printed board. A portable terminal having a frame provided on a printed circuit board, a flexible circuit board connected to the printed circuit board on the frame, and an opening for exposing the operation parts of the plurality of key buttons is formed in the upper case. In the key input device structure of communication equipment,
A restriction member that restricts relative displacement of the key sheet with respect to the opening is formed integrally with the frame, and the restriction member penetrates at least the flexible substrate and is inserted into the key sheet. To do.

  Further, in these key input device structures, an auxiliary restricting member that assists in displacement restriction by the restricting member may be protruded from the upper case toward the key sheet, and the key sheet is elastic rubber. It may be characterized by being a rubber sheet made of.

  The portable communication device of the present invention has any one of the key input device structures described above.

  According to the present invention, even when a portable communication device such as a cellular phone is subjected to an external impact such as dropping, the key sheet constituting the key button is regulated so as not to be displaced relative to the casing. By providing the means to do so, it is possible to improve the reliability of the key input device structure against an impact such as dropping.

  The first effect is that even when a user unexpectedly drops a portable communication device such as a mobile phone and receives an external impact, a portable communication device with improved drop shock resistance can be provided.

  The reason is that the key sheet constituting the key button is configured to protrude toward the key sheet to restrict the positional deviation of the key sheet relative to the operation opening, thereby restricting the key sheet from being displaced due to an external impact such as dropping. This is because it is possible to prevent the key button of the key input device section from entering the operation opening.

  The second effect is that even if the above-described drop impact resistance measures are taken, the influence on the mass of the portable communication device is small.

  The reason is that it is only necessary to use a very small part as a member for regulating the positional deviation, so that the mass of the apparatus is not increased.

  Next, the present invention will be described with reference to the drawings. The portable communication device of the present invention is exemplified by a cellular phone, and the key input device structure will be described.

  FIG. 1 is a perspective view showing an external appearance of a general mobile phone, FIG. 2 is a cross-sectional view showing the structure of a key input device according to the first embodiment of the present invention as viewed along arrow AA in FIG. 1, and FIG. FIG. 4 is a partial perspective view showing an essential part of FIG. 2.

  As shown in FIG. 1, a typical mobile phone is composed of a pair of upper and lower cases 1 and 2 made of resin or the like. On the upper surface side of the upper case 1, there is provided a display device portion having a liquid crystal and a key input device portion 3 in which number keys and the like used when the mobile phone is used are arranged. As shown in FIG. 2, the key input device unit 3 of the first embodiment includes a rubber sheet 3b in which a plurality of key buttons 3a are formed in a housing having an upper case 1 and a lower case 2, and a printed circuit board. 6 is implemented.

  A plurality of key buttons 3a integrated by adhesion to a rubber sheet 3b formed of elastic rubber are penetrated and installed at predetermined positions in the opening 1b on the upper surface of the upper case 1, respectively. The rubber sheet 3 b has an outer shape held by a rib 1 a formed integrally with the upper case 1, and is supported by a plurality of support portions 2 a formed integrally with the lower case 2 and the upper case 1. It is mounted between.

  Referring also to FIG. 3, an electrical component 6 a is mounted on the lower surface of the printed circuit board 6, while there are a plurality of conductive parts 6 b formed on the upper surface of the printed circuit board 6. Further, an extremely thin sheet 4 made of a material such as a polyester film having an adhesive applied to the entire surface is provided so as to cover each of the plurality of conductive portions 6b. A plate-shaped dome 5 that forms a spherical surface with a conductive material such as an ultra-thin metal plate that is adhesively fixed is attached and fixed to the sheet 4. When the user performs a key operation, the convex portion 3c of the rubber sheet 3b elastically deforms the dome 5 and conducts the conductive portion 6b of the printed circuit board 6, thereby detecting a key input.

  As shown in an enlarged view in FIG. 3, at a predetermined position on the printed circuit board 6, a protrusion 7 which is a member for regulating the displacement of the rubber sheet 3b is surface-mounted and fixed by soldering. The protrusion 7 is made of a hard metal plate material such as stainless steel and has a sharp tip. The two protrusions 7 are mounted on and fixed to the printed circuit board 6 as shown in FIG. It is cut and raised into a triangular shape to form a sharp tip.

  A plurality of holes 4 a are formed in the sheet 4 at positions facing the protrusions 7. When the sheet 4 and the key input device unit 3 are assembled on the printed circuit board 6, the protrusions 7 are inserted so as to penetrate the rubber sheet 3 b through the holes 4 a of the sheet 4.

  The mounting and fixing of the protrusion 7 on the printed circuit board 6 is not limited to fixing by soldering, but may be mounting and fixing by adhesion using an adhesive.

  As shown in the perspective view of the sheet 4 and the printed circuit board 6 in FIG. 4, the printed circuit board 6 has a plurality of projections 7 mounted on the surface, and a sheet 4 having a plurality of domes 5 attached and fixed to the back surface with an adhesive. Affixed. On the printed circuit board 6, protrusions 7 and dome 5 penetrating through the holes 4 a are alternately arranged, and a plurality of LEDs (light emitting diodes) 8 are alternately arranged with the dome 5 at another position. By the light emission of the plurality of LEDs 8, the user can easily recognize the key input device unit 3 even in the dark and can be operated.

  The operation of the key input device unit 3 of the first embodiment having such a configuration will be described.

  It is assumed that an external shock is applied by the user dropping the mobile phone unexpectedly. This impact force is transmitted to the inside through the upper case 1 and the lower case 2 and tries to elastically deform the rubber sheet 3b of the key input device unit 3. However, the rubber sheet 3 b has a sharp tip portion of the projection 7 mounted and fixed on the printed circuit board 6 penetrating through the sheet 4. Accordingly, the rubber sheet 3b is the same as when the rubber sheet 3b is fixed to the printed circuit board 6 by the projections 7, and is not elastically deformed by an impact force and does not cause a displacement with respect to the printed circuit board 6. In other words, the relative displacement of the rubber sheet 3b with respect to the opening 1b of the upper case 1 is restricted. That is, it is possible to prevent the key button 3a from entering the housing of the upper case 1 from the opening 1b. Even if the rubber sheet 3b is slightly deformed by a strong impact force, the key button 3a is held at a predetermined position when the shape is restored, and a situation where the key button 3a cannot be operated is avoided.

  Further, in the key input device section 3 of the first embodiment, since the protrusion 7 has a shape that can be automatically soldered and mounted on the printed circuit board 6, the number of assembly steps at the time of manufacture can be reduced, and manual operation is possible. Cost can be reduced compared to solder mounting.

  Next, a second embodiment of the present invention will be described. In the second embodiment, only the shape of the protrusion 7 in the first embodiment described above is different. FIGS. 5A and 5B are a perspective view and a cross-sectional view showing a protrusion in the second embodiment, and FIG. 6 is a perspective view showing a sheet and a printed board.

  As shown in FIG. 5, the protrusion 7a of the second embodiment has a metal sheet metal as a drawing shape, a sharp portion at the tip thereof is conical, and a flange 7b is formed at the other end. The reason why the flange 7b is formed is to ensure the strength of soldering or bonding when mounted on the printed circuit board 6.

  As shown in FIG. 6, a printed circuit board 6 is provided with a plurality of surface-mounted protrusions 7 a and a sheet 4 b having a plurality of domes 5 attached thereto. Further, the projections 7a penetrating the holes 4c of the sheet 4b and the dome 5 are alternately arranged, and a plurality of LEDs 8 are alternately arranged with the dome 5 at another position. The advantage of the second embodiment is that when the sheet 4b is adhesively fixed to a predetermined position of the printed circuit board 6, the protrusion 7a has a conical shape so that the protrusion 7a can be easily passed through the hole 4c. Assembling performance is improved.

  Next, a third embodiment of the present invention will be described. In 3rd Embodiment, the fixing position of the protrusion 7 in 1st Embodiment mentioned above differs. FIG. 7 is a cross-sectional view showing a fixing state of protrusions in the third embodiment, and FIG. 8 is a perspective view showing a sheet and a printed board.

  As shown in FIGS. 7 and 8, the protrusion 7 c of the third embodiment is adhesively fixed to the back surface of the sheet 4 d, that is, the surface facing the printed circuit board 6 in the same manner as the dome 5. The sharp tip of the protrusion 7c penetrates the hole 4e of the sheet 4d and protrudes toward the rubber sheet 3b. A plurality of protrusions 7c and dome 5 are alternately arranged on the sheet 4d, and a plurality of LEDs 8 are alternately arranged with the dome 5 at another position. Such a sheet 4 d is adhesively fixed to a predetermined position of the printed circuit board 6. The advantage of the third embodiment is that since there is no component having a sharp protrusion on the printed circuit board 6 side, the fixing operation of the sheet 4d to the printed circuit board 6 is facilitated, and the assemblability is improved.

  Next, a fourth embodiment of the present invention will be described. In the fourth embodiment, the configuration on the printed circuit board 6 in the first embodiment described above is different. FIG. 9 is a sectional view showing a key input device structure according to the fourth embodiment. In this key input device structure, the description of the same configuration as that of the first embodiment is omitted, and different components will be described.

  On the printed circuit board 6, the electrical component 6 a is mounted on the lower surface and the electrical component 6 c is also mounted on the upper surface in order to improve the component mounting efficiency accompanying the improvement in function and miniaturization of the mobile phone. Accordingly, a metal or resin frame 9 is provided on the printed circuit board 6 between the rubber sheet 3b and covers the electrical component 6c so as to protect it. A flexible substrate 6d that is electrically connected to the printed circuit board 6 via a connector 6g is mounted on the upper surface of the frame 9. A plurality of conductive portions 6f are wired on the upper surface of the flexible substrate 6d and face the dome 5 on the lower surface of the sheet 4f.

  On the upper surface of the frame 9, a plurality of protrusions 9 a are integrally formed as a plurality of regulating members that are partly cut and raised to sharpen the tip, or sharpened by resin molding. The protrusion 9a is inserted so as to penetrate the rubber sheet 3b through the hole 6e formed in the flexible substrate 6d and the hole 4g formed in the sheet 4f. Therefore, even if a force for elastic deformation is applied to the rubber sheet 3b due to an external impact such as dropping, the rubber sheet 3b is prevented from being restrained, and the relative displacement of the upper case 1 of the rubber sheet 3b is restricted. The advantage of the fourth embodiment is that the protrusion 9a can be integrally formed with the frame 9, so that the number of members can be reduced and the cost can be reduced.

  Next, a fifth embodiment of the present invention will be described. In the fifth embodiment, in addition to the configurations of the first to fourth embodiments described above, an auxiliary regulating member is added to the upper case. FIG. 10 is an enlarged cross-sectional view showing the main part of the key input device structure according to the fifth embodiment.

  As shown in FIG. 10, a plurality of bosses 1c as auxiliary regulating members are provided on the lower surface of the upper case 1 so as to protrude toward the rubber sheet 3g.

  The key input unit 3 is integrally formed such that the surface of the hard plastic key button 3d and the rubber sheet 3g is covered with a sheet 3e of polyester film material. Further, as described in the first embodiment, the sheet 4, the dome 5, the printed board 6, and the conductive portion 6b are provided under the rubber sheet 3g, and the protrusions 7 on the printed board 6 are formed on the rubber sheet 3g. Is stuck in.

  In addition, the boss 1c provided on the lower surface of the upper case 1 passes through the hole 3f of the sheet 3e and is inserted into the recess 3h provided in the rubber sheet 3g. Accordingly, the elastic deformation force applied to the rubber sheet 3g due to an external impact such as dropping is not only regulated by the projection 7 but also regulated by the boss 1c which is an auxiliary regulating member. That is, the relative positional deviation with respect to the opening of the upper case 1 of the rubber sheet 3g is more firmly regulated.

  The advantage of the fifth embodiment is that an additional auxiliary restricting member is added to the configuration of any of the first to fourth embodiments, thereby further improving the reliability against a key input operation failure caused by an external impact. It is.

  In the first to fifth embodiments described above, a mobile phone is exemplified as a portable communication device to which the present invention is applied. However, the present invention is not limited to this, and the present invention is also applicable to a PHS (Personal Handyphone System), a car phone, a PDA (Personal Digital Assistant) device having a keyboard and operation buttons, and a portable device.

It is a perspective view which shows the external appearance of a common mobile telephone. It is sectional drawing which shows the key input device structure of the 1st Embodiment of this invention by the AA arrow of FIG. It is sectional drawing which expands and shows the inside of the dashed-dotted line circle | round | yen of FIG. It is a fragmentary perspective view which shows the principal part of FIG. (A) which shows the protrusion in the 2nd Embodiment of this invention is a perspective view, (b) is sectional drawing. It is a perspective view which shows the sheet | seat and printed circuit board of 2nd Embodiment. It is sectional drawing which shows the fixing condition of the protrusion in the 3rd Embodiment of this invention. It is a perspective view which shows the sheet | seat and printed circuit board of 3rd Embodiment. It is sectional drawing which shows the key input device structure of the 4th Embodiment of this invention. It is sectional drawing which expands and shows the principal part of the key input device structure of the 5th Embodiment of this invention. It is sectional drawing which shows an example of the conventional key input device structure. It is sectional drawing which shows the condition when receiving external impacts, such as dropping, in a conventional example. It is sectional drawing which shows the other example of the conventional key input device structure.

Explanation of symbols

1, 21a Upper case 1a, 11a Rib 1b, 11b Opening 1c Boss 2, 21b Lower case 2a, 12a Support 3 Key input device 3a, 3d, 13a, 22 Key button 3b, 3g, 13b Rubber sheet 3c, 13c Convex part 3e, 4, 4b, 4d, 4f, 14 Sheet 3f, 4a, 4c, 4e, 4g, 6e Hole 3h Concave part 5, 15 Dome 6, 16, 26 Printed circuit board 6a, 6c, 16a Electrical component 6b, 6f, 16b Conductive part 6d Flexible substrate 6g Connector 7, 7a, 7c Projection 7b Flange 8 LED
9 Frame 9a Projection 21 Housing 23 Key sheet 24 Projection 25 Metal dome sheet 25a Metal dome

Claims (10)

A key sheet on which a plurality of key buttons are formed and a printed circuit board are mounted in a housing having an upper case and a lower case, and an opening is formed in the upper case to expose an operation portion of the plurality of key buttons. In the key input device structure of the portable communication device,
2. A key input device structure according to claim 1, wherein a restricting member for restricting a relative positional shift of the key sheet with respect to the opening is protruded from a fixed portion adjacent to the key sheet toward the key sheet. The restricting member is a protrusion having a sharp tip, and the protrusion is mounted and fixed to the printed board, and the sharp tip passes through a cover sheet between the key sheet and the printed board. 2. The key input device structure according to claim 1, wherein the key input device structure is inserted into a key sheet. The key input device structure according to claim 2, wherein mounting and fixing of the protrusion to the printed circuit board is performed by soldering. The key input device structure according to claim 2, wherein the mounting and fixing of the protrusion to the printed circuit board is an adhesive. 5. The key input device structure according to claim 2, wherein a tip of the protrusion has a conical aperture shape. The regulating member is a protrusion having a sharp tip, and the protrusion is bonded and fixed to a surface of the cover sheet between the key sheet and the printed board facing the printed board, and the sharp tip is The key input device structure according to claim 1, wherein the key input device structure is inserted into the key sheet through a cover sheet. A key sheet on which a plurality of key buttons are formed and a printed circuit board are mounted in a housing having an upper case and a lower case, and further includes a frame provided on the printed circuit board between the key sheet and the printed circuit board. In the key input device structure of the portable communication device, a flexible board connected by a connector from the printed circuit board is provided on the frame, and an opening for exposing the operation parts of the plurality of key buttons is formed in the upper case.
A restriction member that restricts relative displacement of the key sheet with respect to the opening is formed integrally with the frame, and the restriction member penetrates at least the flexible substrate and is inserted into the key sheet. Key input device structure. The key input device structure according to any one of claims 1 to 7, wherein an auxiliary regulating member that assists in regulating displacement by the regulating member is protruded from the upper case toward the key sheet. 9. The key input device structure according to claim 1, wherein the key sheet is a rubber sheet made of elastic rubber. A portable communication device comprising the key input device structure according to any one of claims 1 to 9.

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