JP2006310451A - Electronic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electronic apparatus that has sufficient strength with smaller size. <P>SOLUTION: The electronic apparatus is provided with a module 100 which incorporates a heating device 301 and comprises shield cases 102 and 103 that cover the device 301. The shield cases 102 and 103 are formed with metal and comprise a contact on inner wall surfaces to which the device 301 contacts, with the wall thickness around the contact 302 being formed thinner than the contact 302. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an electronic apparatus including a module that includes a device that generates heat.

A device mounted on an electronic device generates heat when the electronic device is used. Since this heat may stay in the device, the function of the device may be impaired. Therefore, it is necessary to release heat from the device to the outside. Therefore, for example, a shield case that covers an electronic device is formed of a thin metal plate, and a part of the surface of the shield case that is cut out and bent inward is brought into contact with the device to shield the heat generated from the device. The thing comprised so that it may be made to transmit to a case is proposed (refer patent document 1).
JP 2001-274590 A

  However, in the case of the above configuration, since the shield case is formed of a thin metal plate, sufficient strength against external pressure cannot be obtained. Furthermore, since a predetermined distance must be ensured between the device and the surface of the shield case in order to bring the tongue piece into contact with the device, a predetermined space is required in the shield case. It has become a hindrance to conversion.

  The present invention has been made in view of such circumstances, and an object thereof is to provide an electronic device having sufficient strength and capable of reducing the size of the electronic device.

  The present invention employs the following means in order to solve the above problems. That is, according to the present invention, in an electronic apparatus including a module that includes a device that generates heat and includes a shield case that covers the device, the shield case is formed by metal and contacts the inner wall surface with the device. It has the part.

  In the electronic device of the present invention, the thickness around the contact portion is formed to be thinner than the contact portion.

  In the electronic device of the present invention, the contact portion is supported by an elastic hinge member integrally formed with the shield case.

  According to the electronic device of the present invention, since it is manufactured by metal forming, it becomes strong against external pressure, and thus it is possible to realize a structural strength that does not hinder normal use. In addition, since the shield case has a contact portion that contacts the device, the space between the shield case and the device can be reduced or applied, so that the electronic apparatus can be downsized.

  Hereinafter, embodiments of the present invention will be described with reference to FIG. 1 and FIG. In this embodiment, a portable information terminal, that is, a PDA (Personal Digital Assistance) is described. However, the present invention is not limited to a PDA and can be applied to a portable electronic device. .

1A and 1B are diagrams showing the PDA 10, wherein FIG. 1A is a longitudinal sectional view of the PDA 10, and FIG. 1B is a plan view of the housing 205 of the PDA 10 as seen from the back side. The PDA 10 is configured by mounting a mother board 201 that controls the functions of the PDA 10 in a housing 205 formed in a substantially rectangular parallelepiped shape.
A liquid crystal touch panel 206 is provided on the front side of the housing 205 to display a screen and input information with a stylus pen (not shown). The liquid crystal touch panel 206 is arranged so that the surface thereof coincides with the surface of the housing 205. Yes. In addition, an antenna 203 connected to a module 100 (described later) installed on the mother board 201 via a coaxial cable 204 is attached to the upper end of the housing 205. In addition, an opening 205a to which a coupling connector 208 that communicates with the outside is attached is provided at the lower end of the housing 205.

On the mother board 201, the above-described coupling connector 208 and a plurality of LSIs 209 are mounted. The coupling connector 208 is attached so as to protrude from the lower end of the mother board 201 in order to fit into the opening 205 a of the housing 205. In addition, the plurality of LSIs 209 are attached to the substantially central portion and the lower portion of the front surface and the back surface of the mother substrate 201.
A rechargeable battery 207 that is connected to the coupling connector 208 and charged from an external power source (not shown) is attached to the lower portion of the back surface of the mother board 201.

  A communication module 100 that handles high frequencies is attached to the upper part of the back surface of the mother substrate 201. As shown in FIG. 2, the module 100 covers a printed circuit board 101 on which a device 301 described later and a device 310 such as an IC, a resistor, and a capacitor are mounted, an upper shield case 102 that covers the surface of the printed circuit board 101, and a back surface. And a shield case made of a lower shield case 103. The upper shield case 102 and the lower shield case 103 are formed by die casting metal forming of an aluminum alloy, and are disposed so as to sandwich the printed circuit board 101 and cover the devices 301 and 310 mounted on the printed circuit board 101. Yes.

  The printed board 101, the upper shield case 102, and the lower shield case 103 are provided with a hole (not shown) for passing a screw through the upper shield case 102, and the lower shield case 103 is screwed to face the hole. A hole (not shown) is provided, and the coupling screw 106 is tightened from the upper shield case 102 side to be integrated. Thus, the form of the module 100 can be realized by fastening the upper shield case 102 and the lower shield case 103 with the printed circuit board 101 interposed therebetween. The die-cast metal forming may use a magnesium alloy or a zinc alloy in addition to aluminum.

  On the surface 101 a side of the printed circuit board 101, a coaxial receptacle 104 connected to a coaxial cable 204 extending from the antenna 203 that performs transmission / reception is provided, and power is transmitted to the antenna 203 and signals are transmitted / received through the coaxial receptacle 104. Or Further, an interface connector 105 for transmitting and receiving signals between the module 100 and the mother board 201 is provided at the lower part of the printed circuit board 101 on the back surface 101b side.

  Further, the module 100 is provided with a mounting hole 107 in which a screw is cut in the lower shield case 103 on the interface connector 105 side. The module 100 is mechanically fixed to the mother board 201 by tightening the mounting screws 202 from the mother board 201 side into the mounting holes 107. The lower shield case 103 is coupled to the ground portion of the printed circuit board 101 through a pattern (not shown) on the back surface 101b of the printed circuit board 101, and the upper shield case 102 is similarly patterned on the printed circuit board surface 101a (see FIG. (Not shown) and coupled to the ground portion of the printed circuit board 101. Therefore, if a grounding pattern (not shown) is prepared in a portion of the mother board 201 that contacts the lower shield case 103, the upper shield case 102, the lower shield case 103, the printed circuit board 101 of the module 100, and the mother board 201. The grounded portion has the same potential and is securely connected electrically.

  A device 301 is provided at the center of the printed circuit board 101 on the surface 101a side. The device 301 is in pressure contact with a device contact surface 302 (contact portion) provided on the upper shield case 102. When the amount of heat generation increases, the device 301 dissipates heat into the air. It is like that. Further, around the device contact surface 302, a thin-walled area 303 formed thinner than the average thickness of the upper shield case 102 is provided. The thin-walled area 303 is formed to be thinner than the average thickness of the upper shield case 102, and thus has elasticity in the thickness direction of the upper shield case 102.

  In the PDA 10 having such a configuration, the upper shield case 102 and the lower shield case 103 are used as structural members that require strength, and thus are manufactured by die casting metal forming of an aluminum alloy. It will be more robust to external pressure than those manufactured with sheet metal like technology. Therefore, structural strength that does not hinder normal use such as grasping with a hand or pressing with a finger can be realized. As a result, the space between the housing 205 and the module 100 can be reduced or applied, so that the PDA 10 can be downsized.

  In such a PDA 10, the upper shield case 102 is pressed against the device 301 having a large amount of heat generation, and heat is dissipated into the air through the upper shield case 102. It is possible to prevent the heat from being shielded and covered with the upper shield case 102 to fill the upper shield case 102 and affect other devices. In addition, since the thin portion of the thin-walled area 303 has elasticity, it is possible to absorb variations in height after mounting the device 301 that generates a large amount of heat. Therefore, an excessive force is not applied to the device 301 that generates a large amount of heat, and the damage can be avoided. In addition, it is preferable that the variation is such that the mounting height and the distance between the device contact surface 302 overlap in advance.

  In the above-described embodiment, a pair of U-shaped molded integrally with the upper shield case 102 around the device contact surface 302 as shown in FIG. The leaf spring member 401 (elastic hinge member) may be provided opposite to both sides of the thin-walled area 303. The U-shaped leaf spring member 401 has a pantograph shape when viewed from the side, and can contact the device 301 that generates a large amount of heat. The U-shaped leaf spring member 401 is restrained by the upper shield case 102 at the shield case side fixing portion 402 and further restrained by the device contact surface 302 at the device contact surface side fixing portion 405. Further, in order to ensure the pressure contact between the device 301 having a large amount of heat generation and the device contact surface 302, the mounting height of the device 301 having a large amount of heat generation from the printed circuit board surface 101a is set in advance from the printed circuit board surface 101a to the device contact. It is preferable that the distance is higher than the distance of the surface 302. At this time, the U-shaped leaf spring member 401 is formed symmetrically about the slit 404 formed at the center thereof, and thus is deformed by the same amount around the center. Therefore, the device contact surface 302 translates and can contact the device 301 uniformly and reliably. In the present embodiment, the U-shaped leaf spring members 401 are arranged at two places on the left and right, but the number of places may be three or more as needed. At this time, a hole is formed in the upper shield case 102, but there is no problem if it is carried out within a range where there is no problem in electromagnetic wave shielding.

In the above embodiment, the upper shield case 102 and the device 301 are in direct contact with each other to form a heat dissipation path. However, in order to increase the efficiency of heat dissipation, a heat dissipation sheet with good thermal conductivity is interposed therebetween. Also good. In this case, the shock applied to the device 301 by the upper shield case 102 is reduced by giving elasticity to the heat dissipation sheet. At this time, since the heat dissipation sheet has a predetermined thickness and the height of the module is required, it is disadvantageous for downsizing of the device, while the heat dissipation sheet is thin and has no elasticity in itself, The heat dissipation effect of the device can be obtained by the structure of the shield case.
Moreover, in the said embodiment, although the upper surface of the upper shield case 102 is flat, you may provide a fin in this surface, in order to acquire a thermal radiation effect further.

  In the above embodiment, as shown in FIGS. 4 and 5, an impact is applied to the device 301 that generates a large amount of heat through the device contact surface 302 of the upper shield case 102 against the external pressure (arrow in FIG. 4). In the case where there is anxiety, ribs 501 may be provided around the thin-walled area 303 so that the housing 205 does not directly contact the thin-walled area 303. The rib 501 may be provided on the housing 205 side.

It is a figure which shows PDA which concerns on embodiment in this invention, Comprising: (a) is the longitudinal cross-sectional view, (b) is the top view which decomposed | disassembled the housing | casing of PDA and was seen from the back side. It is a figure which shows the module in PDA, (a) is the top view, (b) is the AA sectional drawing. It is the figure which made a part of module in PDA another structure, Comprising: (a) is the top view, (b) is the BB sectional drawing. It is the fragmentary sectional view which made a part of module in PDA another structure. It is a perspective view of the module shown in FIG.

Explanation of symbols

10 PDA (electronic equipment)
100 module 101 printed circuit board 101a (printed circuit board) front surface 101b (printed circuit board) back surface 102 upper shield case (shield case)
103 Lower shield case (shield case)
201 Mother board 301 Device 302 Device contact surface (contact part)
303 Thin-walled area 401 U-shaped leaf spring member (elastic hinge member)

Claims (3)

In an electronic apparatus comprising a module having a shield case covering a device that includes a device that generates heat and covers the device,
The shield case is molded with metal and has a contact portion with which an inner wall surface contacts the device.     The electronic apparatus according to claim 1, wherein a thickness around the contact portion is formed to be thinner than the contact portion. The electronic device according to claim 1, wherein the contact portion is supported by an elastic hinge member integrally formed with the shield case.

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