JP2015114524A - Electronics - Google Patents

Abstract

Provided is a structure in which a user does not feel uncomfortable by increasing the temperature of a grip for holding a device while improving heat dissipation performance with a small number of parts without increasing the size of the electronic device. A metal exterior cover that covers the front surface of an electronic device and has a partially expanded grip, a low thermal conductivity decorative member that is fixed to the exterior of the exterior cover, and an electrical element that generates heat are mounted. A circuit board, an elastic and thermally conductive first thermal conductive member that contacts the surface of the electronic element, and an elastic and thermally conductive second thermal conductive member that contacts the inner wall surface of the exterior cover; A heat transfer member in contact with the surfaces of the first and second heat conducting members, and an opening is provided between the bulging portion and the non-bulging portion of the exterior cover, so that the second heat The conductive member contacts the inner wall surface of the non-bulged portion of the outer cover, and the opening of the outer cover is closed with the inner member and the decorative member. [Selection] Figure 1

Description

  The present invention relates to an electronic apparatus including a circuit board on which an electric element that generates heat is mounted.

  In a digital camera, usually, an optical image is formed on an image sensor with a zoom lens, and image data obtained by photoelectric conversion with the image sensor, for example, image data in a file format such as JPEG is subjected to compression processing. Data is temporarily stored in the memory and then stored on the recording medium.

  Such digital cameras are rapidly becoming increasingly high-pixel as one of high-performance elements as space-saving of internal mechanical mechanisms and high-density mounting of electronic parts are progressing as miniaturization.

  The number of pixels is high for elements that perform processing such as converting analog signals obtained from image sensors to digital signals, and image processing semiconductor elements that perform arithmetic processing that converts digital signals to the optimum state required by the user. As a result, the number of processes has increased.

  These elements are driven at a high frequency in order to perform high-speed processing. However, since the charge necessary for processing one pixel has hardly decreased, the amount of heat generated by the elements tends to increase.

  On the other hand, with the downsizing of digital cameras, the internal heat dissipation space tends to decrease, and the heat accumulated without being able to dissipate heat in the internal space is used for image quality deterioration due to image sensor performance deterioration, other internal elements, etc. Causes direct damage.

  To solve this problem, a heat dissipation member having higher thermal conductivity than the frame is sandwiched between a circuit board on which a heat generating electronic element is mounted and a frame for fixing the circuit board, and the heat generating electronic element and the heat dissipation member It has been proposed to make contact through heat-dissipating rubber (see Patent Document 1).

JP 2007-134610 A

  However, in the digital camera disclosed in Patent Document 1, heat is transferred by bringing an electronic element that generates heat and a heat radiating member into contact with each other through a heat radiating rubber to dissipate heat, and the heat is guided from the heat radiating member to the rear case 40. Heat is released outside the equipment. However, since the rear case is an exterior member and is a part that is easily touched by the user, if the locally heated rear case part becomes extremely hot, it is possible that the user may feel uncomfortable.

  An object of the present invention is to provide a structure that does not give the user a sense of incongruity by improving the heat dissipation performance with a small number of parts without increasing the size of the electronic device, while the grip on which the user holds the device becomes hot. To do.

  In order to achieve the above object, an electronic device according to the present invention includes a metal outer cover that covers a front surface of an electronic device and has a partially bulged grip, and is fixed to the outside of the outer cover and is heated more than the metal. A decorative member made of a material having low conductivity, a circuit board on which an electrical element that generates heat is mounted, an elastic and thermally conductive first thermal conductive member that contacts the surface of the electronic element, and the exterior A second heat conductive member having elasticity and thermal conductivity that contacts the inner wall surface of the cover; and a heat transfer member that contacts the surfaces of the first and second heat conductive members. An opening is provided between the bulging portion and the non-bulging portion, the second heat conducting member contacts an inner wall surface of the non-bulging portion of the exterior cover, and the opening of the exterior cover is It is characterized by being covered with a decorative member.

  According to the present invention, without increasing the size of the electronic device, it is possible to improve the heat dissipation performance with a small number of components and to prevent the user from feeling uncomfortable by increasing the temperature of the grip that holds the device.

2 is a cross-sectional view illustrating an internal structure of the digital camera 1. FIG. 1 is an external view of a digital camera 1. FIG. 1 is an exploded perspective view of a digital camera 1. FIG. It is a disassembled perspective view of a front cover component.

[Example 1]
Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

(First embodiment)
FIG. 2 is an external perspective view of the digital camera 1 as the first embodiment of the electronic apparatus embodying the present invention. 2A is an external perspective view of the digital camera 1 viewed from the front side, FIG. 2B is an external perspective view of the digital camera 1 viewed from the back side, and FIG. It is an external view of the digital camera 1 seen from the upper surface.

  The digital camera 1 is fixed with a photographic lens barrel 2 that forms a subject image on an image sensor. The taking lens barrel 2 is a retractable zoom lens that is extended when the digital camera 1 is in use, as shown in FIG.

  An imaging element such as a CCD or a CMOS image sensor that photoelectrically converts an optical image to generate image data is disposed behind the photographic lens barrel 2.

  Further, the digital camera 1 is provided with a circuit board (detailed later) on which a processing circuit that performs image processing on the output from the image sensor is mounted.

  As shown in FIG. 2A, a strobe light emission window 3, a release button 4, a zoom lever 5, and a power button 6 are provided above the digital camera 1. The release button 4 can be pressed in two stages. By performing the first-stage pressing operation on the release button 4, a shooting preparation operation (photometry operation, distance measurement operation, etc.) is started. By performing a second-stage pressing operation on the release button 4, the subject is photographed, and the image data of the subject image is recorded on the recording medium. The zoom lever 5 is a rotary operation type lever disposed on the outer periphery of the release button 4. When the power button 6 is pressed, the digital camera 1 is switched between a use state (shooting enabled state) and a non-use state (shooting disabled state). When switched to the use state by the power button 6, the retracted photographic lens barrel 2 is extended, and the digital camera 1 is ready for photographing.

  As shown in FIG. 2A, on the left side of the digital camera, a grip portion 1a bulging in the forward direction of the camera is provided so that the user can easily hold the device with the right hand during shooting.

  Above the photographic lens barrel 2, a pair of microphone holes 1 b are provided for taking sound into a microphone built in the digital camera 1.

  A battery lid (not shown) is provided below the digital camera 1. The battery lid opens and closes a battery storage chamber for storing a battery serving as a power source for the digital camera 1 and a storage chamber for storing a recording medium for recording photographed image data.

  As shown in FIG. 2B, a power supply and signal input / output jack is provided on the side surface of the digital camera 1, and a jack protecting cover member 8 covers the input / output jack. By opening the cover member 8, various cables can be inserted into and removed from the input / output jack.

As shown in FIG. 2B, a display monitor 9 is provided on the back surface of the digital camera 1. A plurality of operation buttons 10 are provided beside the display monitor 9. The cross button arranged at the center of the plurality of operation buttons 10 can be pushed into four places in the vertical and horizontal directions and one central portion.
As shown in FIG. 2C, the above-described grip portion 1a bulges from other portions, and holding this grip portion prevents the user from accidentally dropping the device. .

  Next, the internal structure of the digital camera 1 will be described.

  FIG. 3 is an exploded perspective view of the digital camera 1.

  The digital camera 1 is covered with two metal exterior covers, a front cover 20 and a rear cover 40, and two resin exterior covers, a top cover 50 and a side cover 60. An inner member 21 is bonded and fixed to the inside of the front cover 20 with a double-sided tape (not shown). The inner member 21 is formed of a resin material having insulating properties and low thermal conductivity (heat insulating properties). A decorative ring 23 formed of a metal material disposed around the lens barrel 2 is bonded and fixed to the front cover 20.

  On the outside of the front cover 20, a decorative member 26 and a rubber member 27 that improves gripping properties are fitted. The decorative member 26 is formed of a resin material having insulating properties and low thermal conductivity (heat insulating properties). The rubber member is a member obtained by two-color molding, and is formed of an elastic thermoplastic elastomer on the outer surface side of the digital camera and a resin material having an insulating property and low thermal conductivity (heat insulating property) on the inner side.

  The front cover 20 includes the above-described bulged grip portion 20a (described as 1a in the assembled state of the digital camera), the other non-bulged portion 20b, and an extension extending from the non-bulged portion. A protruding portion 20c is formed. Further, an opening 20d is provided between the bulging grip portion 20a and the extending portion 20c. A decorative member 26 and a rubber member 27 are arranged outside the front cover 20 so as to cover the opening 20d, and an inner member 21 is arranged inside the front cover 20.

  The decorative member 26 and the rubber member 27 are fixed to the front cover by fastening the screws (details will be described later) so that the inner member 21 and the rubber member 27 sandwich the extended portion 20c of the front cover and the decorative member.

  Inside the digital camera 1, a photographic lens barrel 2 that forms a subject image on an image sensor is disposed substantially at the center. In FIG. 3, a strobe unit having a strobe light emission window 3 is disposed on the right side of the photographing lens barrel 2, and a circuit board 14 is disposed on the left side of the photographing lens barrel 2. The circuit board 14 is mounted with a CPU 14a, which is an electrical element that controls the operation of the digital camera 1 and generates heat during operation, and a main memory 14b that temporarily stores various signals. The circuit board 14 is fixed by screws to a main chassis (not shown) made of metal which is a main structure of the digital camera.

  Between the circuit board 14 and the inner member 21, a heat transfer member 22 made of a metal material having a high thermal conductivity is disposed. The heat transfer member 22 is fastened to the main chassis using screws 28. Thermal conductive rubbers 29 and 30 having high thermal conductivity are affixed to the circuit board side of the heat transfer member 22 so as to elastically contact the surfaces of the CPU 14a and the main memory 14b. Further, a heat conductive rubber 31 having a high thermal conductivity is attached to the front cover side of the heat transfer member 22 so as to elastically contact the inside of the front cover.

  Thereby, the heat generated from the electric elements 14 a and 14 b is transmitted to the heat transfer member 22 through the heat conductive rubbers 29 and 30. The heat transferred to the heat transfer member 22 is thermally diffused by a heat path transferred from the screw 28 to the main chassis and a heat path transferred to the non-bulged portion 20b of the front cover via the heat conductive rubber 31. The Further, since the heat transfer member 22 is electrically at the same potential as the main chassis and is disposed above the circuit board, it also has an effect of shielding electromagnetic waves emitted from the circuit board 14. The front cover is made of a high thermal conductivity aluminum material having a thermal conductivity of 100 W / mK or more, and the front cover is made of a material having an emissivity of 0.9 or more so that heat is easily radiated.

  Next, the component configuration attached to the front cover will be described with reference to FIG.

  FIG. 4 is an exploded perspective view of components attached to the front cover as viewed from the back side.

  Self-tapping portions 27c, 27d, and 27e for fixing screws are provided on the back surface of the rubber member. Reference numerals 33a, 33b, and 33c denote screws, which are inserted into the extended portion 20c of the front cover of the inner member 21 and the holes provided in the decorative member 26, and fastened to the self-tap portions 27c, 27d, and 27e of the rubber member. .

  The front inner 21a is provided with an opening 21a so as to avoid the heat conductive rubber 31 described in FIG. A half-cut 20e is provided around the opening 20d of the front cover so as to compensate for a decrease in strength due to the opening.

  Next, the cross-sectional configuration and heat transfer path of the grip portion of the digital camera 1 will be described.

  FIG. 1 is a diagram illustrating the configuration of the grip portion of the digital camera, and is a cross-sectional view taken along the position X in FIG.

  20a is a bulging grip of the front cover, 20b is a non-bulging portion, 20c is an extending portion extending from the non-bulging portion, 20d is an opening portion, and 20e is a half-cut portion around the opening portion. . Reference numeral 26 denotes a decorative member, which is disposed so as to cover the opening 20d and the half punched portion 20e of the front cover and to contact the extending portion 20c. 27a is a two-color molded elastomer portion having elasticity, and 27b is a resin portion. Here, PC (polycarbonate) is used for the resin portion 27b, and a self-tap portion 27d is provided in the resin portion.

  Similarly, 27c and 27e described in FIG. 4 are provided in the resin portion. An inner member 21 has a shape along the inner surface of the front cover, and is fixed to the front cover with a double-sided tape 24. If an opening such as 20d is provided in the front cover, the rigidity of the front cover is inevitably lowered, and when the grip part 20a is gripped by the user, it is easily deformed, leading to a deterioration in the quality of the digital camera. In order to prevent a decrease in the rigidity of the front cover, the opening 20d of the front cover is closed on the outer side by the decorative member 26 and is closed by the inner side inner member 21, and the rubber member 27, the decorative member 26, the front side are closed by the screws 33b. The extended portion 20c of the cover and the inner member 21 are fastened together. By doing so, the rigidity of the front cover is maintained.

  14 is a circuit board, 14a is a CPU mounted on the circuit board, and 14b is a main memory mounted on the circuit board. These two electric elements are the main heat sources of the digital camera. Thermal conductive rubbers 29 and 30 are arranged so as to contact the surfaces of the CPU 14a and the main memory 14b. The heat generated in the CPU 14a and the main memory 14b is transmitted to the heat radiating plate 22 through the heat conductive rubbers 29 and 30, and is transmitted to the non-bulged portion 20b of the front cover through the heat conductive rubber 31. Yes. The heat is transmitted to the extended portion 20c of the front cover, but the opening 20d becomes a heat insulating portion so as not to be transmitted to the bulging grip portion.

  By doing so, the heat generated in the CPU 14a and the main memory 14b, which are the main heat sources of the digital camera, can be made difficult to be transmitted to the grip 20a held by the user. Further, since the inner member 21 is disposed inside the grip 20a, it is difficult to receive radiant heat from the inside of the digital camera, and the grip portion 20a is not easily heated.

  In the present embodiment, with such a configuration, it is possible to provide a structure in which the grip of the digital camera 1 held by the user is heated and the user does not feel uncomfortable.

  As mentioned above, although preferable embodiment of this invention was described, this invention is not limited to these embodiment, A various deformation | transformation and change are possible within the range of the summary.

DESCRIPTION OF SYMBOLS 1 Digital camera 1a Grip part 14 Circuit board 14a Electric element (CPU)
14b Electric element (main memory)
20 Front cover 20a Swelling grip part 20b Non-swelling part 20c Extension part 20d Opening part 20e Half-out part 21 Inner member 22 Heat transfer member 26 Cosmetic member 27 Rubber member 29 Thermal conduction rubber 30 Thermal conduction rubber 31 Thermal conduction rubber

Claims (3)

A metal exterior cover (20) having a grip (1a, 20a) partially covering the front surface of the electronic device (1);
A decorative member (26, 27) made of a material fixed to the outside of the exterior cover and having a lower thermal conductivity than metal;
A circuit board (14) on which an electrical element that generates heat is mounted;
A first heat conducting member (29, 30) having elasticity and thermal conductivity in contact with the surface of the electronic element;
A second heat conductive member (31) having elasticity and thermal conductivity in contact with the inner wall surface of the outer cover;
A heat transfer member (22) in contact with the surfaces of the first and second heat conducting members,
An opening (20d) is installed between the bulging portion (20a) and the non-bulging portions (20b, 20c) of the outer cover, and the second heat conducting member is a non-bulging portion of the outer cover. In contact with the inner wall surface of (20b),
An electronic apparatus, wherein an opening of the exterior cover is closed by the decorative member (26, 27).   The opening of the outer cover is closed by an inner member (21) made of a material that is fixed to the inner side of the outer cover and has a lower thermal conductivity than metal, and the outer cover is used as the inner member and the decorative member. The electronic device according to claim 1, wherein the screw is fixed so as to be sandwiched between the two.   The electronic apparatus according to claim 1, wherein the outer periphery of the outer cover has a half-recessed recess (20 e).