JP2010107633A - Electronic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electronic apparatus in which unwanted radiation and autotoxemia can be reduced, while securing waterproofing function. <P>SOLUTION: The electronic apparatus has a display panel arranged at a metal frame, a circuit board performing signal processing of the display panel, and an aperture part. The electronic apparatus is provided with: a first case part fixing the display panel, at the aperture part position so as to expose the display plane; a second case part fixing the circuit board; and an elastic member for waterproof pressed against and held in between them at the vicinity of the outer periphery of the first case part and the second case part. The circuit board has an ground-exposing part exposing a ground conductor at an end part, the first case member has a contact part which carries out electrically conducting contact of the metal frame and the ground-exposing part at the aperture part end, and the contact part is constituted so that contact of the ground-exposing part and the contact part is strengthened by the repulsive force for press in the elastic member for waterproofing. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an electronic device. In particular, the present invention relates to an electronic device having a waterproof function.

  In recent years, as represented by one-segment broadcasting (abbreviation for one segment partial reception service for mobile phones and mobile terminals), there has been an increase in the number of small portable electronic devices that can receive digital broadcasting and display video and audio. ing.

  On the other hand, for use in, for example, bathrooms and kitchens, there is an increasing demand for electronic devices that have a configuration in which a gap between casings is sealed with a rubber material or the like so that moisture does not enter the electronic device.

  In these electronic devices, in addition to the problem of unnecessary radiation of electromagnetic waves, a problem called self-poisoning, in which the reception sensitivity of digital broadcasting deteriorates due to radiation noise generated by the electronic device itself, has been increasing. These factors are known to be caused by the unstable signal ground in the device.

  Therefore, the housing of the electronic device is formed of metal or conductive resin, the ground of the electronic circuit board is connected to the metal housing, and the signal ground is strengthened to suppress radiation noise and self-poisoning. Further, by using a metal casing or a conductive resin casing as the casing, there is an effect of suppressing unnecessary electromagnetic radiation emitted from the electronic device or reducing noise entering an external antenna.

For example, Patent Document 1 proposes a method for achieving both a waterproof function and a shield structure using conductive rubber.
Japanese Patent Laid-Open No. 5-308198

  However, even in these structures, the stability of the signal ground of the circuit board may be insufficient.

  The present invention has been made in view of the above problems, and an object thereof is to provide an electronic device that can reduce unnecessary radiation and self-poisoning while ensuring a waterproof function.

The electronic device of the present invention is
A display panel installed in a metal frame;
A circuit board for signal processing for the display panel;
A first housing portion having an opening and fixing the display panel at the opening position so that the display surface is exposed;
A second housing portion for fixing the circuit board;
A waterproof elastic member that is pressed and sandwiched near the outer periphery of the first housing part and the second housing part,
The circuit board is
At the end, it has a ground exposed portion where the ground conductor is exposed,
The first housing member is
At the end of the opening, it has a contact portion that conductively contacts the metal frame and the ground exposed portion,
The contact portion is
It is comprised so that the contact with the said ground exposure part may become strong with the repulsive force with respect to the press in the said elastic member for waterproofing.

  According to the electronic device of the present invention, it is possible to provide an electronic device that can reduce unnecessary radiation and self-poisoning while ensuring a waterproof function.

  Hereinafter, embodiments according to the present invention will be described with reference to the drawings. In the following embodiments, the same components are denoted by the same reference numerals, and the description thereof may be omitted.

(Embodiment 1)
A portable liquid crystal display device according to an embodiment of the present invention will be described with reference to FIGS.

  FIG. 1A is an exploded perspective view showing a schematic configuration of a portable liquid crystal display device 1 according to Embodiment 1 of the present invention. FIG. 1B is a front view of the portable liquid crystal display device 1. In the present embodiment, the positive z-axis direction shown in FIG. 1A is the upward direction, the negative z-axis direction is the downward direction, the x-axis direction is the left-right direction, and the positive y-axis direction is shown. The front direction, the front direction, or the display surface direction, and the negative y-axis direction may be referred to as the rear surface direction or the back surface direction.

  The liquid crystal display device 1 broadly includes a liquid crystal panel 10, a display surface side housing 11, a back side housing 12, an external antenna 13, an electric circuit board 14, and a waterproof member 15.

  The liquid crystal panel 10 is arranged so that the display surface is exposed in the opening of the display surface side housing 11. The liquid crystal panel 10 receives electrical signals from the electrical circuit board 14 and displays various information such as images and characters on the display surface. The back side of the liquid crystal panel 10, that is, the side opposite to the display surface is covered with a metal frame.

  FIG. 2 is a partial cross-sectional view showing a part of the AA cross section in FIG. As described above, the liquid crystal panel 10 is provided with the metal frame 101 on the back side. The main body of the liquid crystal panel 10 is housed and installed in the frame frame 101. Here, the main body refers to a main part that performs the display function of the liquid crystal panel 10, and a description thereof is omitted.

  The display-side housing 11 and the back-side housing 12 are made of a resin material. The display surface side housing 11 and the back surface side housing 12 constitute an external housing so as to include the electric circuit board 14 therein. The display-side casing 11 has an opening, and holds the liquid crystal panel 10 so that the display surface of the liquid crystal panel 10 is exposed from the opening as described above. An electric circuit board 14 is fixed to the rear housing 12 on the inner side.

  A plurality of bowl-shaped contact portions 110 are provided inside the display-side housing 11. The contact portion 110 is configured such that the hook-shaped portion engages with the back surface of the electric circuit board 14 when the display housing 11 and the back housing 12 are fitted. The contact part 110 is disposed so as to surround the electric circuit part 14. In FIG. 1A, the contact members are described only on the left and right sides of the display surface side casing 11 and the back side casing 12, and are not described on the upper and lower sides. Although it actually exists on the upper and lower sides, the description is omitted for easy understanding of the drawing.

  The display-side housing 11 and the back-side housing 12 are made of a resin material, but an aluminum-deposited conductive film 200 is formed on the inner surface shown by the hatched area in FIG. The conductive film 200 portion and the frame frame 101 are configured to be in conductive contact. The conductive film 200 is also formed on the contact portion 110, and the display-side housing 11 and the electric circuit board 14 are electrically connected via the contact portion 110.

  FIG. 3 is an enlarged view of the contact portion 110 in the display surface side housing 11. The contact portion 110 has a bowl-like configuration as described above, and has a contact surface 111 that contacts the ground exposed portion 140 of the electric circuit board 14 and a contact surface 112 that contacts the side surface of the frame frame 101. . In the present embodiment, the contact surface 111 is formed such that the normal direction thereof substantially coincides with the normal direction of the display surface.

  The external antenna 13 is a dipole antenna and can receive radio waves of terrestrial digital broadcasting. The external antenna 13 is attached so as to be rotatable, and the direction of the external antenna 13 can be changed as appropriate according to the reception status of radio waves. The external antenna 13 is electrically connected to the electric circuit unit 14.

  Various electric components are mounted on the electric circuit board 14, and the electric signal received by the external antenna 13 is processed and sent to the liquid crystal panel 10 as an electric signal that can be displayed on the liquid crystal panel 10. Various signal processing for the liquid crystal panel 10 is performed based on external information input from the user of the portable liquid crystal display device 1 in addition to the signal received by the external antenna 13. As described above, the electric circuit board 14 performs various kinds of signal processing, and thus becomes a generation source of electromagnetic noise.

  FIG. 4 is a schematic view of the back surface of the electric circuit board 14. The electric circuit board 14 is provided with a ground exposed portion 140 in which a ground conductor is exposed at a peripheral portion on the back surface thereof. The contact surface 111 of the contact part 110 mentioned above contacts this ground exposed part 140.

  The waterproof member 15 is made of a rubber material having elasticity. Specifically, for example, chloroprene rubber can be used. The waterproof member 15 is disposed so as to be pressed and sandwiched between the display surface casing 11 and the back side casing 12. The waterproof member 15 is provided inside the display surface housing 11 and the back-side housing 12 and in the vicinity of the outer periphery. The waterproof member 15 is provided outside the contact part 110 and the contact part 120. That is, the waterproof member 15 is disposed so as to surround the electric circuit portion 14, the contact portion 110, and the contact portion 120. Therefore, the waterproof member 15 plays a role of a waterproof function that prevents moisture from entering the electric circuit board 14 from the outside.

  As shown in FIG. 2, the waterproof member 15 is disposed so as to be sandwiched between fixing portions 201 provided on the display surface side housing 11 and the back surface side housing 12, respectively. On the further outer side of the fixing part 201 and the waterproof member 15, a screwing part 202 for fixing the display surface side casing 11 and the rear side casing 12 with screws 16 is arranged. By tightening the screw 16 at the screwing portion 202, the waterproof member 15 is pressed to perform a waterproof function.

  The waterproof member 15 generates a repulsive force in the direction indicated by the arrow in FIG. 2 in response to the pressing of the display surface side casing 11 and the back side casing 12. Due to the repulsive force of the waterproof member 15, a force acts on the display surface side housing 11 in the upward direction in FIG. 2 and the back surface side housing 12 in the downward direction in FIG. 2. That is, a force acts on the contact surface 111 of the contact portion 110 in the upward direction, and the ground exposed portion 140 of the electric circuit board 14 acts in the downward direction. According to such an action, the direction of the repulsive force of the waterproof member 15 acts in a direction that strengthens the contact between the contact surface 111 and the ground exposed portion 140. Therefore, it works in the direction of decreasing the contact impedance.

  According to such a configuration, the system ground of the electric circuit board 14 can be brought into contact with the housing with a low impedance by a repulsive force against the pressing in the waterproof member 15. In other words. System ground can be stabilized.

  In the present embodiment, the conductive film 200 is an aluminum vapor-deposited material, but is not limited thereto. For example, the same effect can be obtained as long as it has conductivity such as electroless plating. Further, as the display surface side case 11 and the back side case 12, those having conductivity by kneading a conductive filler such as carbon may be used. In addition, although it increases the cost, a metal casing may be used.

  Moreover, in this Embodiment, although the contact part 110 provided inside the display surface side housing | casing 11 was comprised with the same resin material as the display surface side housing | casing 11, it is not restricted to this. For example, the contact part 110 may be formed of a conductive material as a separate body.

  Moreover, in this Embodiment, although the shape and arrangement | positioning of the contact part 110 were as shown in FIG. 1 and FIG. 3, it is not restricted to this. For example, it may be of a wide shape as shown in FIGS. FIG. 5 is a schematic perspective view of a configuration having a contact portion 110a having a wide shape, and FIG. 6 is an enlarged view of the contact portion 110a. According to such a configuration, the contact area can be increased and the contact impedance can be further reduced.

  In the present embodiment, the shape shown in FIG. 3 is used as the shape of the contact portion, but is not limited thereto. For example, the one shown in FIG. 7 may be used. FIG. 7 shows an enlarged view of the contact portion 110b. The contact portion 110 b has a first protrusion 113 a at a contact portion with the frame frame 101 and a second protrusion 113 b at a contact portion with the ground exposed portion 140. By setting it as such a structure, the force at the time of the contact part 110b contacting the frame frame 101 and the ground exposed part 140 by the pressing force which arises by expansion / contraction of the waterproof member 15 increases. Therefore, the system ground of the electric circuit board 14 is further stabilized, and it is possible to further reduce unnecessary electromagnetic radiation and home poisoning.

  Further, the shape of the protrusions 113a and 113b is not limited to the semicircular shape as shown in FIG. For example, trapezoidal protrusions 114a and 114b may be used as shown in FIG. The trapezoidal shape can increase the contact area as compared to the semicircular shape. Therefore, the contact force can be increased, the contact area can be increased, the system ground of the electric circuit board 14 can be further stabilized, and unnecessary electromagnetic radiation / self-poisoning can be further reduced.

  In the present embodiment, the ground exposed portion 140 is configured to expose the entire circumference at the end of the electric circuit board, but is not limited thereto. For example, it is good also as a structure which exposes only the part which contacts a contact part. In this way, portions other than the ground exposed portion can be effectively used for mounting circuit components.

  In the present embodiment, a portable liquid crystal display device having a rectangular display surface and casing as an example of an electronic device has been described as an example. However, the present invention is not limited to this. For example, as shown in FIG. 9, it is also possible to apply to a display panel or a case having a circular outer shape.

  In the present embodiment, an example in which a liquid crystal panel is used as a display panel is shown, but the present invention is not limited to this. For example, the present invention can be applied to an electronic device using an organic EL panel or an inorganic EL panel.

  In the present embodiment, a portable liquid crystal display device is shown as an example of the electronic device, but the present invention is not limited to this. For example, the present invention can be applied to a mobile phone, a portable music player, a digital camera, a digital video camera, and the like. In short, any electronic device having a waterproof function can be applied.

  Moreover, the display surface side housing | casing 11 in this Embodiment is an example of a 1st housing | casing part. Moreover, the back side housing | casing 12 in this Embodiment is an example of a 2nd housing | casing part. Further, the waterproof member 15 in the present embodiment is an example of a waterproof elastic member.

  The electronic apparatus of the present invention can be applied to, for example, a portable liquid crystal display device having a waterproof function, a cellular phone, a portable music player, a digital camera, a digital video camera, and the like.

(A) An exploded perspective view showing a schematic configuration of a portable liquid crystal display device according to an embodiment of the present invention, (b) a front view of the portable liquid crystal display device. 1 is a partial cross-sectional view of a portable liquid crystal display device according to an embodiment of the present invention. Enlarged view of contact area Schematic view of the back of the electric circuit board The disassembled perspective view which shows schematic structure in another structural example of the portable liquid crystal display device which concerns on embodiment of this invention. Enlarged view of the contact part in another configuration example Sectional view of a contact portion having a semicircular protrusion Cross-sectional view of a contact portion having a trapezoidal protrusion The perspective view which shows the structure at the time of applying to a circular electronic device

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 1a, 1b Portable liquid crystal display device 10, 10a Liquid crystal panel 11 Display surface side housing | casing 12 Back side housing | casing 13 External antenna 14 Electric circuit board 15 Waterproof member 16 Screw 101 Frame frame 110, 110a, 110b, 110c Contact part 111, 112 Contact surface 113a, 113b, 114a, 114b Projection part 200 Conductive film 201 Fixing part 202 Screwing part

Claims (4)

A display panel installed in a metal frame;
A circuit board for signal processing for the display panel;
A first housing portion having an opening and fixing the display panel at the opening position so that the display surface is exposed;
A second housing portion for fixing the circuit board;
A waterproof elastic member that is pressed and sandwiched near the outer periphery of the first housing part and the second housing part,
The circuit board is
At the end, it has a ground exposed portion where the ground conductor is exposed,
The first housing member is
At the end of the opening, it has a contact portion that conductively contacts the metal frame and the ground exposed portion,
The contact portion is
It is configured so that contact with the ground exposed portion is strengthened by a repulsive force against pressing in the waterproof elastic member.
Electronics. The contact portion is
It has a bowl shape having a contact surface in contact with the ground exposed portion,
The contact surface is
It is located opposite to the ground exposed portion, and is configured to press against the ground exposed portion by a repulsive force against pressing in the waterproofing elastic member.
The electronic device according to claim 1. The contact portion is
A first protrusion that contacts the ground exposed portion;
A second protrusion that contacts the metal frame,
The electronic device according to claim 1. The contact portion is
Arranged to surround the entire electrical circuit,
The electronic device according to claim 1.

Images