JP2018148545A - Electronic apparatus, imaging apparatus, and accessory - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve heat dissipation efficiency without increasing the size of an apparatus.SOLUTION: An electronic apparatus comprises: a fan with a suction port; a duct section with an opening corresponding to the suction port of the fan; a circuit board connected to the duct part and disposed with respect to the duct part so as to be layered opposite the fan; a first cover disposed opposite the fan with respect to the circuit board and composing part of outer covering; and a second cover composing part of outer covering in a direction substantially perpendicular to a direction of layering of the duct part and the circuit board. The duct part has a plurality of first extension parts extended so as to surround the circuit board, and a second extension part extended in a direction substantially perpendicular to the direction of layering. The first extension part is fixed to the first cover, and the second extension part is fixed to the second cover.SELECTED DRAWING: Figure 7

Description

  The present invention relates to an electronic device.

  In recent years, along with a demand for downsizing of electronic equipment, downsizing and high density of mounting components inside the equipment have become prominent. On the other hand, there is an increasing demand for higher functionality and higher performance of devices, and the amount of heat generated by devices is increasing. Since the operation of a device in a high temperature environment causes a malfunction of a mounted component inside the device, a performance deterioration, and a failure of the device, a recent electronic device is required to have a high heat dissipation performance.

  Therefore, when the amount of heat released by natural heat dissipation is not sufficient with respect to the amount of heat generated by the device, a heat dissipation structure by forced air cooling using a fan is used. For example, as a structure for collectively cooling mounted components widely distributed on the circuit board, the circuit board and the mounted components that are heat sources are connected to the duct, and the air taken in by the intake air of the fan is passed through the duct. The thing is known (patent documents 1 and 2). In these structures, a plurality of fins are arranged in the duct to expand the heat radiation area and improve the heat radiation performance.

  The duct shown in Patent Document 1 is connected to a board to be radiated through a heat conducting member, and a plurality of fans are arranged in parallel at a position different from the board projection surface. As a result, high heat dissipation performance can be obtained over a wide range in the substrate to be radiated. The duct is provided with an intake port for sucking air from the outside and openings for guiding the intake air from the intake port to a plurality of fans, and further branched to correspond to each of the plurality of fans. The flow path is provided linearly. A plurality of linear fins parallel to the main flow direction in each flow path are arranged in parallel, and an increase in ventilation resistance is suppressed. On the other hand, the duct shown in Patent Document 2 is attached to a substrate to be radiated, and a fan is disposed on the substrate projection surface, thereby suppressing an increase in size of the duct in a plane parallel to the substrate. The imaging unit and the fan are arranged on a plane orthogonal to the optical axis, and the imaging unit, the fan, the duct, and the substrate are arranged along a direction parallel to the optical axis, so that the heat of the substrate is transferred to the imaging unit. It is hard to tell.

JP 2006-122718 A JP 2014-44293 A

  However, in the structure of Patent Document 1, heat dissipation is realized by a forced air cooling mechanism using a duct and a fan, but a sufficient heat dissipation effect cannot be obtained against the recent trend of increasing the amount of heat generated by circuit boards. . In addition, many conventional electronic devices such as digital video cameras have exterior parts made of resin. Since the heat of the forced air cooling mechanism is difficult to be transferred to the resin exterior, only exhaust heat using the intake and exhaust ports has been considered. In addition, since the fans are arranged at positions away from the projection surface of the substrate to be radiated and a plurality of fans are used for a plurality of flow paths, the apparatus becomes large.

  Since the duct shown in Patent Document 2 is configured to be attached to a substrate to be radiated, it is necessary to separately use a sheet metal or the like in order to fix the substrate to the electronic device main body. In general, ducts formed by aluminum die-casting have high rigidity, whereas the board has low rigidity, and the board is usually fixed at the edge (edge) so as not to disturb the arrangement of the duct and fan. Is done. Therefore, it cannot be said that the electronic device has sufficient rigidity against external compression and torsion. In particular, since the imaging unit and the forced air cooling mechanism are arranged along the optical axis direction, the rigidity against an external force applied in the optical axis direction is insufficient. In this case, if the rigidity is increased, a new member is added, which increases the number of parts and increases the cost. In Patent Document 2, a fin is not disposed directly under the air intake of the fan in order to suppress an increase in ventilation resistance caused by the fin in the vicinity of the air intake of the fan. For this reason, on the circuit board to be radiated, the heat radiating performance immediately below the air inlet of the fan is lower than that of the other parts, and there is a possibility that the temperature becomes locally high.

  By the way, the power consumption and the amount of heat generated by the mounted components as heat sources vary, and it is normal that a large distribution of the amount of generated heat occurs on the circuit board. However, in the structures of Patent Documents 1 and 2, when there is a mounted component that generates a large amount of heat locally, the component may become abnormally hot. Therefore, when there is a calorific value distribution, there is a problem that it is difficult to equalize the temperature of the substrate and the mounted component while avoiding the enlargement of the apparatus. In either of Patent Documents 1 and 2, use in an outdoor environment during stormy weather is not assumed. As a simple measure in case of rain or stormy weather, there is a possibility that the vent hole is blocked when the electronic device is covered with a rain cover. When the ventilation hole is blocked, there are problems that the ventilation performance is lowered and a part of the exhaust heat flows into the intake air and the heat dissipation function cannot be sufficiently maintained.

  An object of this invention is to improve the thermal radiation efficiency.

  In order to achieve the above object, the present invention relates to a fan having an air inlet, a duct having an opening corresponding to the air inlet of the fan, and the fan connected to the duct. A circuit board disposed so as to be laminated on the opposite side of the circuit board, a first cover that is disposed on the opposite side of the circuit board from the fan and that constitutes a part of the exterior, and the duct portion. A second cover that constitutes a part of the exterior in a direction substantially perpendicular to the stacking direction with the circuit board, and the duct portion extends to surround the circuit board. And a second extension part extending in a direction substantially perpendicular to the stacking direction, the first extension part being fixed to the first cover, and the second extension part. The extending portion is fixed to the second cover.

  ADVANTAGE OF THE INVENTION According to this invention, the thermal radiation efficiency of an electronic device can be improved, without enlarging an apparatus.

It is a perspective view of an electronic device provided with a heat dissipation structure. It is a disassembled perspective view of an imaging device system. It is a side view of the XZ plane in an imaging device system. It is a perspective view of a fan. It is a disassembled perspective view of a thermal radiation unit. It is a perspective view in the assembly state of the 1st unit. It is a disassembled perspective view of the imaging device containing the principal part of a thermal radiation structure. It is a side view of a duct base to which a main board and a power board are attached. It is a rear view of the duct base with which the main board and the power supply board were attached. It is a front view of a duct base. It is a disassembled perspective view of a duct part. It is sectional drawing which follows the AA line of FIG. It is a front view of a duct base. It is a front view of a duct base. It is a perspective view of an accessory. It is the figure which looked at the imaging device of an accessory wearing state from the front. It is detail drawing of the B section of FIG. It is the perspective view which looked at the imaging device in the accessory wearing state from the upper part and the lower part. It is the perspective view which looked at the imaging device in the wearing state of an accessory and a rain cover from the lower part.

  Embodiments of the present invention will be described below with reference to the drawings.

(First embodiment)
FIGS. 1A and 1B are perspective views of an electronic apparatus including a heat dissipation structure according to the first embodiment of the present invention. An imaging device is exemplified as this electronic device, but the type of electronic device to be applied is not limited. FIGS. 1A and 1B are perspective views of an imaging apparatus system in which the detachable interchangeable lens 2 is attached to the imaging apparatus 1 as viewed from the front and the rear, respectively.

  In the following description, the side (subject side) where the interchangeable lens 2 is attached to the imaging apparatus 1 is referred to as the front side. As shown in FIGS. 1A and 1B, three-dimensional coordinates are set. Here, the X, Y, and Z axis directions in the figure correspond to the front-rear, left-right, and up-down directions, respectively. In addition, about the left-right direction, it calls with the direction seen from the front side. Specifically, the direction from the imaging device 1 toward the subject in the optical axis direction of the interchangeable lens 2 is the X-axis positive direction, the left side when viewed from the front side is the Y-axis positive direction, the X-axis direction, and the vertical direction perpendicular to the Y-axis direction. It is defined as the positive direction of the Z axis. Therefore, the Z-axis positive direction is referred to as upward, the Z-axis negative direction as downward, the Y-axis positive direction as left, the Y-axis negative direction as right, the X-axis positive direction as forward, and the X-axis negative direction as backward.

  The interchangeable lens 2 is attached to the front side of the imaging device 1 and attached to a lens mount 3 provided in the imaging device 1. In the lens mount 3, a screw part having knobs 3 a and 3 b is rotated counterclockwise around the optical axis as viewed from the front side, and a claw part (not shown) provided on the interchangeable lens 2 is pulled back. The method is adopted. However, the present invention is not limited to this. For example, a known bayonet type in which the interchangeable lens 2 is fixed to the imaging apparatus 1 by rotating around the optical axis may be used. The exterior of the imaging device 1 mainly includes a front cover 13, a rear cover 11, a bottom cover 12, and a top cover 4. The top cover 4 is bonded with an intake side duct cover 5 (FIG. 1A) on the right side and an exhaust side duct cover 6 (FIG. 1B) on the left side. The heat inside the imaging device 1 is dissipated by forced air cooling using air taken from the outside by a fan 130 (described later in FIG. 4). The intake-side duct cover 5 is provided with a first external intake port 51 and a second external intake port 52 for introducing outside air, and the exhaust-side duct cover 6 transmits the introduced air to the outside of the imaging device 1. An external exhaust port 60 is provided for discharging to the outside. The top cover 4, the intake side duct cover 5 and the exhaust side duct cover 6 constitute a top cover unit.

  FIG. 2 is an exploded perspective view of the imaging apparatus system with the top cover unit removed. The top cover 4 is substantially U-shaped, and insertion nails 7a and 7b are provided at the lower right end and the lower left end, respectively. Insertion grooves 8 (the left side is not shown) corresponding to the claws 7a and 7b are provided at the lower right end and the lower left end of the bottom cover 12, respectively.

  The top cover unit can be attached to the imaging device 1 by the following procedure. The operator slides the top cover unit in the negative Z-axis direction along the ribs extending in the X-axis negative direction and the positive direction respectively provided on the outer periphery of the front cover 13 and the rear cover 11. Thereafter, the operator inserts the claws 7 a and 7 b of the top cover 4 into the insertion groove 8 (the left side is not shown) of the bottom cover 12, and attaches the top cover unit to the imaging device 1 with the screws 9.

  FIG. 3 is a side view of the XZ plane in the imaging apparatus system, and is shown with the top cover unit removed. The front base 14 is attached to the lens mount 3. The ND unit 15 is disposed between the lens mount 3 and the image sensor 16. The light that has passed through the interchangeable lens 2 passes through the ND unit 15 and then forms an image on the image sensor 16 on the sensor substrate 17.

  The image sensor 16 attached to the sensor substrate 17 is fixed to the sensor plate 18 by UV bonding. The fan 130 is attached to the duct base 100 fixed to the rear cover 11. Further, a main board 300 which is a circuit board is connected to the duct base 100. The component mounting surface of the main substrate 300, the main substrate mounting surface of the duct base 100, and the intake surface of the fan 130 (the plane including the rear edge of the circular intake port 131; see also FIGS. 4 and 12) are all YZ. Parallel to the plane. The fan 130 is disposed such that its intake surface overlaps the main board 300 when viewed in the X-axis direction. Thereby, the enlargement of the imaging device 1 in the YZ plane is avoided.

  FIG. 4 is a perspective view of the fan 130 as viewed obliquely from the rear. The fan 130 is a centrifugal fan, and has a feature that a large air volume is easily obtained even in a flow path having a large ventilation resistance. The intake port 131 opens in a substantially circular shape on the back side of the fan 130, and the exhaust port 132 opens on the side surface side of the fan 130. Inside the fan 130, there are provided a plurality of blades that rotate to suck air from the air inlet 131 and exhaust it from the air outlet 132, and a motor that rotates these blades. The fan 130 exhausts air that has been taken in from the X-axis negative direction to the positive direction through the intake port 131 from the exhaust port 132 in the Y-axis positive direction. Note that it is not essential to use a centrifugal fan for the fan 130, and for example, an axial fan may be used.

  As shown in FIG. 3, the duct base 100 is provided with a first duct opening H1 and a second duct opening H2. The first duct opening H1 and the second duct opening H2 are formed at positions corresponding to the first external intake port 51 and the second external intake port 52 of the intake side duct cover 5 in the mounted state of the top cover unit. Has been. Therefore, by driving the fan 130, external air can be introduced into the imaging apparatus 1 through the duct openings H1 and H2. On the other hand, on the exhaust side, the fan 130 is arranged so that the exhaust port 132 corresponds to the external exhaust port 60 (FIG. 2) provided in the exhaust side duct cover 6. The air sucked by the fan 130 is used for cooling the inside of the imaging device 1 and then exhausted to the outside of the imaging device 1.

  The sensor substrate 17 shown in FIG. 3 converts the light received by the image sensor 16 into an electrical signal. The main board 300 is electrically connected to the sensor board 17 and performs image processing and video output. A large number of electrical components serving as heat sources are mounted on any of the substrates. The heat generated in the sensor substrate 17 is diffused mainly to the sensor plate 18 by heat conduction, and then is transferred to the air inside the image pickup apparatus 1, and finally to the outside air by natural heat dissipation through the exterior of the image pickup apparatus 1. Heat is dissipated. The sensor plate 18 is made of, for example, a high thermal conductivity material such as an aluminum alloy, and effectively diffuses and dissipates heat generated in the sensor substrate 17.

  The heat generated in the main board 300 is forcibly air-cooled mainly by the heat dissipation unit 1000 shown in FIG. The structure of the heat dissipation unit 1000 will be described with reference to FIGS.

  FIG. 5 is an exploded perspective view of the heat dissipation unit 1000. The heat radiating unit 1000 includes a first unit 1001, a second unit 1002, a main substrate 300 serving as a main heat source, and members 301a, 301b, 301c, 301d, 302a, 302b, 302c, and screws 202, all of which are made of a heat conductive material. Have. The second unit 1002 is configured by fixing the heat diffusion plate 201 to the main substrate holder 200 with screws. The main board 300 is sandwiched between the first unit 1001 and the second unit 1002 at the front and back, and is fixed by screws 202.

  Mounted components 311a, 311b, 311c, and 311d, which are electronic components, are mounted on the front surface (surface on the X axis positive direction side) of the main substrate 300, and also on the rear surface (surface on the X axis negative direction side) of the main substrate 300. An electronic component (not shown) is mounted. Here, when the first unit 1001 is assembled, a member 301a, 301b, 301, 301d having a shape corresponding to each of the mounting components 311a, 311b, 311c, 311d is interposed between the main board 300 and the first unit 1001. Are held in a compressed state. Between the main board 300 and the second unit 1002, members 302a, 302b, 302c having shapes corresponding to the respective electronic components (not shown) are sandwiched in a compressed state. Thus, it is ensured that the first unit 1001 and the second unit 1002 are thermally connected to the main board 300 to be radiated heat (so that heat conduction is possible).

  In the first unit 1001, the duct lid 140 and the fan 130 are fixed to the duct base 100 with screws 143 and 142. The duct base 100 and the duct lid 140 constitute a duct portion. The duct lid 140 is formed with a lid opening H 0 as an opening corresponding to the air inlet 131 of the fan 130. The shape of the lid opening H0 is a circle centered on the fan drive shaft O (the rotation center of the motor that rotates the blades of the fan 130), and the diameter thereof is equal to or greater than the diameter of the air inlet 131 of the fan 130. Thereby, the air in the duct can be smoothly guided to the air inlet 131. Further, a cushion member 141 is attached to the duct lid 140 so as to cover the outer edge of the lid opening H0. The cushion member 141 is clamped between the duct lid 140 and the fan 130 to prevent air leakage between the two members.

  The material of the duct base 100 is, for example, an aluminum die cast that is a highly rigid and high thermal conductivity material. The material of the heat diffusion plate 201 is preferably a high thermal conductivity material such as a copper plate or an aluminum alloy plate. Heat generated on the front surface (the surface on the X-axis positive direction side) of the main substrate 300 is transmitted to the first unit 1001 side mainly through the members 301a to 301d. Then, the heat is diffused to the duct base 100 and a plurality of fins (first fin group 110, second fin group 120) disposed integrally therewith (for these fin groups 110, 120, see FIG. 10). Etc.).

  Although details will be described later with reference to FIG. 10 and the like, in the assembled state of the first unit 1001, two flow paths are formed between the duct base 100 and the duct lid 140, both connected to the air inlet 131. These two flow paths are the first flow path F1a of the first heat radiation part F1 and the second flow path F2a of the second heat radiation part F2. The first duct opening H1 is an intake opening corresponding to the first heat radiation part F1, and the second duct opening H2 is an intake opening corresponding to the second heat radiation part F2. The path from the first duct opening H1 to the lid opening H0 (or intake port 131) is the first flow path F1a, and from the second duct opening H2 to the lid opening H0 (or intake port 131). Is the second flow path F2a. By the operation of the fan 130 attached to the duct base 100, outside air is taken in from the first duct opening H1 and the second duct opening H2. Thereby, it ventilates between the several fin groups 110 and 120 provided in the duct base 100, and the heat of the fin groups 110 and 120 transfers to air. Any air that flows in is guided to the air inlet 131 of the fan 30 through the lid opening H0 of the duct lid 140 and then exhausted from the air outlet 132.

  FIG. 6 is a perspective view of the first unit 1001 in the assembled state. The air taken in from the first duct opening H1 and the second duct opening H2, respectively, is formed between the duct base 100 and the duct lid 140 as the first cooling air w1 and the second cooling air w2. It passes through two flow paths (flow paths F1a, F2a). And after cooling the inside of a duct, the cooling winds w1 and w2 are discharged | emitted from the exhaust port 132 of the fan 130 as the exhaust wind w0.

  The intake / exhaust path described above has a substantially sealed structure except for the intake / exhaust port provided in the exhaust side duct cover 6. Therefore, even when dust or water droplets enter from the intake / exhaust port, they can be kept in the ventilation path or discharged from the exhaust port. Thereby, it is possible to prevent the performance deterioration or failure of the imaging apparatus 1 due to dust or water droplets entering the intake / exhaust path.

  On the other hand, the heat generated on the rear surface (surface on the X axis negative direction side) of the main substrate 300 is diffused mainly to the heat diffusion plate 201 and the main substrate holder 200 (FIG. 5) constituting the second unit 1002. Thereafter, the heat is radiated to the air inside the imaging apparatus 1 and then naturally radiated to the outside air through the exterior of the imaging apparatus 1. Comparing heat dissipation paths for radiating the front surface (surface in the X-axis positive direction) and the rear surface (surface in the X-axis negative direction) of the main board 300, forced air cooling by the first unit 1001 on the front surface becomes dominant. . For this reason, it is desirable that the mounting components having a relatively large amount of heat generation be concentrated on the front surface (surface in the positive direction of the X axis) of the main board 300. A ground pattern (not shown) provided on the main board 300 is in contact with the duct base 100. Thereby, the heat of the main board 300 itself can be transmitted to the duct base 100.

  FIG. 7 is an exploded perspective view of the imaging device 1 including the main part of the heat dissipation structure. The heat radiating unit 1000 is disposed so that the upper part is surrounded by the sheet metal member 19, the lower part is surrounded by the bottom cover 12, and the rear part is surrounded by the rear cover 11 (see FIG. 3 and the like). In addition, by assembling the top cover unit as shown in FIG. 2, the horizontal direction (Y-axis positive / negative direction) of the heat radiating unit 1000 is also maintained. As described above, the top cover 4 has a substantially U-shape that is open in the negative Z-axis direction. In the assembled state of the top cover unit, the portion having the intake side duct cover 5 and the portion having the exhaust side duct cover 6 in the top cover unit are positioned so as to sandwich the heat radiating unit 1000 including the duct base 100 from the left and right directions. .

  As shown in FIG. 7, from the duct base 100, a plurality of arm portions 105a, 105b, and 105c, which are first extending portions, surround the main substrate 300, and are rearward in the optical axis direction (X-axis negative direction). ). The distal ends of the arm portions 105a, 105b, and 105c are fixed to the rear cover 11 with screws 150. Further, bosses 106 a and 106 b are formed to protrude in the positive Z-axis direction from the upper end portion of the duct base 100, and the bosses 106 a and 106 b are fixed to the sheet metal member 19 with screws 151. From the lower end of the duct base 100, a plurality of second extending portions bosses 107a and 107b are formed protruding in the Z-axis negative direction, and the bosses 107a and 107b are fixed to the bottom cover 12 with screws 152. The heat of the main board 300 is dissipated mainly by forced cooling. However, part of the heat of the duct base 100 is transmitted to the rear cover 11 and the bottom cover 12 via the arm portions 105a, 105b, 105c and the bosses 107a, 107b, respectively, and is radiated. The rear cover 11 and the bottom cover 12 are both made of a metal material such as magnesium die cast. Therefore, the heat transmitted from the duct base 100 is diffused in each cover and is naturally radiated. Therefore, the heat radiation effect is higher than that of a cover formed of resin or the like, and heat spots (locally hot spots) are also generated. Easy to prevent.

  By the way, the arrangement of the fan 130, the duct base 100, the main board 300, the rear cover 11, and the bottom cover 12 is arranged as follows. The main board 300 is disposed so as to be laminated on the duct base 100 on the side opposite to the fan 130 (X-axis negative direction side). The rear cover 11 is disposed on the opposite side (X-axis negative direction side) of the main substrate 300 from the fan 130 and constitutes a part of the exterior. The bottom cover 12 and the top cover 4 constitute a part of the exterior in a direction (Z-axis positive / negative direction) substantially perpendicular to the stacking direction of the duct base 100 and the main substrate 300.

  As shown in FIGS. 2 and 3, the sheet metal member 19 is fixed so as to connect the front cover 13 and the rear cover 11 at the upper part of the imaging device 1. The bottom cover 12 is fixed at the lower part of the imaging device 1 so as to connect the front cover 13 and the rear cover 11. As described above, the duct base 100 is fixed to the sheet metal member 19 and the bottom cover 12 by the bosses 106a and 106b and the bosses 107a and 107b at the upper and lower parts, and further to the rear cover 11 by the arm parts 105a, 105b, and 105c. Fixed. As a result, it is possible to increase rigidity against external force, particularly compression and torsion in the optical axis direction. As described above, since the surrounding cover is fixed by the duct base 100 (partially via the sheet metal member 19) made of a highly rigid material such as aluminum die cast, a new part for improving the rigidity. It is possible to increase the rigidity of the imaging device 1 without adding. Although the upper end portions (bosses 106a and 106b) of the duct base 100 are fixed to the sheet metal member 19, they may be fixed to the top cover 4 located on the upper surface side of the electronic device. Note that the top cover 4 may also be made of a metal material.

  The power supply board 400 is attached to the duct base 100 via the main board holder 200 and is electrically connected to the main board 300 via a connector (not shown). FIG. 8 is a side view of the XZ plane of the duct base 100 to which the main board 300 and the power supply board 400 are attached. As shown in FIG. 8, a gap with a distance D is formed between the main substrate 300 and the power supply substrate 400. This gap is provided for the purpose of avoiding the components mounted on the surfaces of the substrates from hitting each other and making it difficult to transfer the heat generated from the main substrate 300 to the power supply substrate 400, and the distance D is suitable for the purpose. The value of is determined. Further, the heat generated from the power supply substrate 400 is diffused and naturally radiated to the heat diffusion plate 401 provided on the rear surface side (X-axis negative direction side) of the power supply substrate 400. From this point of view, it is desirable that the mounting components having a relatively large amount of heat generation be concentrated on the rear surface (surface in the negative direction of the X axis) of the power supply substrate 400.

  FIG. 9 is a rear view of the duct base 100 to which the main board 300 and the power board 400 are attached. The main board 300 is formed with recessed relief portions 300a, 300b, 300c. The escape portions 300a, 300b, and 300c are provided in order to avoid interference with the arm portions 105a, 105b, and 105c of the duct base 100, and have a shape that is cut out so as to escape the arm portions 105a, 105b, and 105c. . Thereby, the duct base 100 and the rear cover 11 can be connected so as to be able to transfer heat without increasing the size of the duct base 100, and expansion of the outer shape of the imaging device 1 can be suppressed. The main board 300 is directly connected to the duct base 100, and the duct base 100 is connected to a metal exterior cover (covers 11, 12, etc.) as described above. As a result, there is no potential difference between the ground pattern of the main substrate 300 and the exterior cover, and stable GND can be ensured. Furthermore, since the main board 300 is covered with metal parts (covers 11 and 12 and sheet metal member 19), a shielding effect from external unnecessary electromagnetic waves can be expected.

  FIG. 10 is a front view of the duct base 100. A circle Hp indicated by an alternate long and short dash line in FIG. 10 is a projection shape of the lid opening H0 (FIG. 5) onto the duct base 100. The first heat radiating portion F1 and the second heat radiating portion F2 are separated by the separation wall 101. That is, the first flow path F1a from the first duct opening H1 to the intake port 131 and the second flow path F2a from the second duct opening H2 to the intake port 131 are formed with the separation wall 101 therebetween. Is done. The first heat radiating portion F1 corresponds to the mounting components 311a and 311b, and the second heat radiating portion F2 is provided at a position corresponding to the mounting components 311c and 311d. When viewed in the X-axis direction, the mounting components 311c and 311d are arranged in the projection region of the first heat radiation part F1 with respect to the main board 300, and the mounting parts 311a and 311b are the projections of the second heat radiation part F2 with respect to the main board 300. Arranged in the area.

  The main flow direction of the air flowing through the first flow path F1a and the second flow path F2a is referred to as a main flow direction. The first flow path F1a has a substantially linear shape, and the main flow direction of the cooling air w1 flowing through the first flow path F1a is linear. On the other hand, the second flow path F2a has a substantially bent shape that is bent substantially at a right angle in the middle of the main flow direction. Since the cooling air w2 flowing through the second flow path F2a changes the traveling direction at a substantially right angle in the middle, the ventilation resistance is relatively large with respect to the cooling air w1. Note that the two cooling airs w1 and w2 shown here are examples for ease of understanding, and in fact, air flows are generated in the entire flow paths.

  Here, the channel length in each channel is different. The position of the fan drive shaft O (arrangement of the fan 130) and the position of the lid opening H0 are designed so that the first flow path F1a is shorter than the second flow path F2a. . When comparing the lengths of the flow paths F1a and F2a, the lengths of the flow paths F1a and F2a are defined as the shortest distance from the duct openings H1 and H2 to the fan drive shaft O. Alternatively, the lengths of the flow paths F1a and F2a may be defined by the shortest distance from the duct openings H1 and H2 to the edge of the air inlet 131.

  A plurality of fins are formed integrally with the duct base 100 in each of the first heat radiation part F1 and the second heat radiation part F2. That is, the first heat radiating portion F1 has a plurality of first fin groups 110 (fins 111a, 111b, 111p), and the second heat radiating portion F2 has a plurality of second fin groups 120 (fins 121a, 121b, 121c).

  First, a plurality of first fin groups 110 are arranged in parallel in a direction substantially perpendicular to the main flow direction of the first flow path F1a. Each of the first fin groups 110 is divided into a plurality in the main flow direction, and the fins 111a, 111b, and 111p are arranged in order from the side closer to the first duct opening H1. Each of the fins 111a, 111b, and 111p is a protrusion that is substantially parallel to the main flow direction, and protrudes in the positive X-axis direction. Regarding the length of the first flow path F1a in the main flow direction, the length L1 of the fin 111a is the longest, and the length L2 of the fins 111b and 111p is common and shorter than the length L1 of the fin 111a. The fin 111p is present in a region facing the lid opening H0. The protrusion heights of the fins 111a and 111b in the positive direction of the X axis are the same, and the protrusion height of the fin 111p is lower than that of the fins 111a and 111b (also described in FIG. 12).

  A plurality of second fin groups 120 are arranged in parallel in a direction substantially perpendicular to the main flow direction of the second flow path F2a. Each of the 2nd fin group 120 is divided | segmented into plurality with respect to the mainstream direction, and the fin 121a, 121b, 121c is arrange | positioned in an order near the 2nd duct opening H2. Each of the fins 121a, 121b, and 121c is a protrusion that is substantially parallel to the main flow direction and protrudes in the positive X-axis direction. The lengths of the fins 121a, 121b, 121c in the main flow direction of the second flow path F2a are different from each other, and the fin 121a is the longest among the fins 121a, 121b, 121c. The protrusion heights of the fins 121a, 121b, and 121c in the positive X-axis direction are common. Although the fins 121a and 121b are linear, the shape of the fin 121c near the bent portion of the second flow path F2a is gently curved. As a result, an increase in ventilation resistance at a portion where the flow direction of the cooling air w2 changes its traveling direction at a substantially right angle is suppressed.

  FIG. 11 is an exploded perspective view of the duct portion. 12 is a cross-sectional view taken along line AA in FIG. By disposing the fins 111p in a substantially projected region of the lid opening H0 onto the duct base 100, the heat dissipation performance of the first unit 1001 with respect to the heat source facing the air inlet 131 is enhanced. Since the protruding height of the fin 111p is lower than the other fins (fins 111a and 111b) disposed on the duct base 100, the performance degradation of the fan 130 due to the influence of an obstacle near the air inlet 131 is avoided. .

  A dashed arrow shown in FIG. 12 represents the cooling air w1. Of the fins disposed on the duct base 100, all the fins except the fin 111p are formed high in a range not interfering with the duct lid 140, similarly to the fins 111a and 111b shown in FIG. Thereby, the space | gap between a fin front-end | tip and the duct lid | cover 140 can be made small as much as possible, and the cooling wind w1 can be reliably passed between a fin.

  The fin 111p is formed lower in the positive direction of the X-axis than the other fins, and a gap of length Δx is provided between the tip of the fin 111p and the intake surface of the fan 130. When the air gap Δx is too small, the fan performance deteriorates due to the influence of the fins 111p in the vicinity of the air inlet 131. On the other hand, when the gap Δx is too large, the heat radiation area of the duct base 100 facing the air inlet 131 is reduced. Therefore, in the present embodiment, the area represented by the product of the gap Δx and the peripheral length (π × φdf) of the intake port 131 is approximately the same as the opening area of the exhaust port 132 (FIG. 4) of the fan 130. Thus, the height of the fin 111p is set. φdf is the diameter of the air inlet 131. Thereby, the heat radiation area of the duct base 100 facing the air inlet 131 is increased without reducing the fan performance (that is, without reducing the air volume).

  Further, when the cooling air w1 travels from the first duct opening H1 to the air inlet 131, a part thereof passes through the side surface and the tip of the fin 111p. Therefore, the heat transfer coefficient in the fins 111p increases, a high heat dissipation effect can be obtained in the region facing the air inlet 131 of the fan 130, and the temperature of the heat dissipation target can be made uniform over a wide range.

  Further, as shown in FIG. 10, the fin 111p is a part of a region facing the air inlet 131 of the fan 130, specifically, a part closer to the first duct opening H1 than the fan drive shaft O. It is provided only in the area. The region near the fan drive shaft O has a small flow velocity and a small temperature reduction effect even in the region facing the air inlet 131. By not providing the fin 111p in such a region where the temperature reduction effect is small, the fin shape can be simplified and reduced in weight. The configuration is not limited to this, and for example, the fins 111p may be provided in the entire region facing the intake port 131.

  In the first fin group 110 and the second fin group 120, each fin is divided with respect to the main flow direction of the corresponding flow paths F1a and F2a, so that compared with a configuration in which the fins are extended without being divided. The surface area and heat transfer coefficient of the fins that contribute to heat dissipation can be increased. Thereby, a high heat dissipation effect can be obtained in the first unit 1001.

  Moreover, the division | segmentation number per unit length of the fin with respect to each mainstream direction has more direction of the 1st thermal radiation part F1 than the 2nd thermal radiation part F2. In the example of FIG. 10, the number of fins of the first fin group 110 per unit length in the main flow direction is larger than the number of fins of the two fin groups 120. As the number of divided fins increases, the surface area and the heat transfer coefficient increase, and the ventilation resistance also increases. Therefore, the increase in the ventilation resistance becomes significant in the first heat radiation portion F1.

  On the other hand, the flow path length of the first flow path F1a is shorter than that of the second flow path F2a, and the ventilation resistance is small. Therefore, even when the fins are divided in a large number in the main flow direction, the first heat radiation part F1 is sufficient. Ventilation rate can be obtained. Furthermore, the opening area of the first duct opening H1 is larger than that of the second duct opening H2, and the first heat radiating part F1 is easier to inhale than the second heat radiating part F2. Therefore, it is easy to obtain a desired air volume in the first heat radiation part F1.

  With such a duct structure, the first heat radiating portion F1 can radiate heat more efficiently than the second heat radiating portion F2. For this reason, the total power consumption of the mounting components 311c and 311d that are the main heat dissipation targets of the first heat dissipation portion F1 is larger than the total power consumption of the mounting components 311a and 311b that are the main heat dissipation targets of the second heat dissipation portion F2. The mounting parts are arranged as follows. In addition, it is desirable that the mounted components having high power consumption and high heat generation are concentrated on the front surface side (X-axis positive direction side) of the main substrate 300 and in the projection region of the first heat radiation part F1.

  In addition, since the first fin group 110 and the second fin group 120 are provided integrally with the duct base 100, the temperature of the circuit board is higher than when a plurality of ducts are provided for heat dissipation of the main board 300. Can be made more uniform. Therefore, it is possible to prevent the mounted component from being locally heated. Of the fins disposed in the heat radiation portions F1 and F2, the fins (fins 111a and 121a) closest to the duct openings H1 and H2 are compared to the fins (fins 111b and 121b) adjacent to the downstream side in the main flow direction. Long. Thereby, it can prevent that the air taken in from the outside is overheated in the vicinity of the entrance of the flow paths F1a and F2a. Therefore, by flowing relatively cool air also in the second half of the flow path, the temperature from the first half to the second half of the flow path can be made more uniform. Note that the length of the fins may be gradually shortened toward the rear of the flow paths F1a and F2a.

  According to the present embodiment, the flow path length of the second flow path F2a is longer than the flow path length of the first flow path F1a, and the first fins disposed in the first heat radiation portion F1. The group 110 is divided into a plurality in the main flow direction of the first flow path F1a. The number of fins per unit length in the main flow direction is that of the first fin group 110 disposed in the first heat radiation part F1 rather than the second fin group 120 disposed in the second heat radiation part F2. There are more. That is, by effectively increasing the number of divisions of the fin with the shorter flow path length, an effective heat dissipation structure that takes into account the heat flow balance of the heat sources distributed over a wide range can be realized. In addition, since the fan 130 is single, the apparatus does not increase in size. Therefore, the heat radiation efficiency can be improved, and in particular, the temperature of the substrate and the mounted component can be made uniform even if there is a calorific value distribution without increasing the size of the apparatus.

  In addition, the total power consumption of the mounting component group disposed in the projection region of the first heat radiation part F1 with respect to the main substrate 300 is the mounting component group disposed in the projection region of the second heat radiation part F2 with respect to the main substrate 300. Greater than the total power consumption. Thus, heat is largely radiated by the first heat radiating portion F1 having relatively high heat radiating efficiency, which contributes to uniform temperature of the mounted components.

  Of the fins disposed in the heat radiating portions F1 and F2, at least the first fin group 110 only needs to be divided into a plurality of parts in the main flow direction, and the second fin group 120 is not divided. Also good.

  Also according to the present embodiment, the duct base 100 includes the first extending portion (arm portions 105a, 105b, 105c) extending so as to surround the main substrate 300, and the Z-axis negative direction. It has the 2nd extended part (boss | hub 107a, 107b) extended. The arms 105a, 105b, and 105c are fixed to the rear cover 11 (first cover) disposed on the back side, and the bosses 107a and 107b are fixed to the bottom cover 12 (second cover) disposed on the bottom side. Is done. Thereby, the heat of the duct base 100 is transmitted to the metal rear cover 11 and the bottom cover 12 to be efficiently radiated. Therefore, the heat dissipation efficiency can be improved. Further, the arm portions 105 a, 105 b and 105 c are fixed to the rear cover 11, and the bosses 107 a and 107 b are fixed to the bottom cover 12, and the bosses 106 a and 106 b are fixed to the sheet metal member 19. As a result, the rigidity of the imaging device 1 can be increased without increasing the number of components. Moreover, a substantially U-shaped top cover 4 (third cover) that covers the duct portion from above and from the side is disposed so as to sandwich (pinch) the duct portion (particularly the duct base 100) from the left and right directions. Therefore, the imaging device 1 has a more robust configuration.

  Further, the main board 300 is provided with relief portions 300a, 300b, and 300c for avoiding interference with the arm portions 105a, 105b, and 105c, which contributes to downsizing of the imaging device 1.

(Second Embodiment)
FIG. 13 is a front view of the duct base 102 in the heat dissipation structure of the electronic device according to the second embodiment. The present embodiment includes a duct base 102 instead of the duct base 100 as compared to the first embodiment. Note that the same components as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

  The duct base 102 includes second fins 220 corresponding to the second fin group 120. The second fin 220 has a different shape from the second fin group 120 of the duct base 100 and is not divided. Moreover, in the duct base 100 in 1st Embodiment, the arrangement pitch of the direction orthogonal to the mainstream direction of the fin groups 110 and 120 was common. On the other hand, in the duct base 102, the arrangement pitch is different between the first fin group 110 and the second fin 220. Other configurations of the duct base 102 are the same as those of the duct base 100.

  A plurality of first fin groups 110 are arranged at a pitch p1 in parallel in a direction (substantially Z-axis direction) perpendicular to the main flow direction of the first flow path F1a. A plurality of second fins 220 are arranged at a pitch p2 in parallel in a direction perpendicular to the main flow direction of the second flow path F2a. The pitch p1 is smaller than the pitch p2. Accordingly, relatively more fins can be disposed in the first heat radiation portion F1, and the heat radiation area can be increased. As described above, since the flow path length of the first heat radiating portion F1 is shorter than that of the second heat radiating portion F2, the first fin group 110 is arranged at a narrow pitch in the first heat radiating portion F1 as described above. Even in this case, a sufficient air volume can be obtained. On the other hand, in the second heat radiating part F2 having a relatively long flow path length, it is possible to obtain a necessary air volume by increasing the fin pitch p2 and reducing the ventilation resistance. Thereby, cooling with good balance can be performed.

  According to the present embodiment, the same effects as those of the first embodiment can be obtained with respect to uniformizing the temperature of the substrate and the mounted component even if there is a calorific value distribution without increasing the size of the apparatus. it can. In addition, since the pitch p2 of the second fins 220 is larger than the pitch p1 of the first fin group 110, the required flow rate can be obtained by reducing the ventilation resistance in the second heat radiation part F2. Accordingly, for example, when the fan 130 is rotated at a low speed or a small fan is used, when the static pressure of the fan is relatively small and it is difficult to ventilate the air necessary for the second heat radiating portion F2. It is also possible to make the temperature of the heat dissipation object uniform.

  Note that, from the viewpoint of reducing the ventilation resistance, the second fins 220 provided in the second heat radiating portion F2 are not divided in the mainstream direction. However, as in the first embodiment, the second fins 220 are divided into a plurality in the mainstream direction. May be.

(Third embodiment)
FIG. 14 is a front view of the duct base 103 in the electronic apparatus according to the third embodiment. The present embodiment includes a duct base 103 instead of the duct base 100 as compared to the first embodiment. Note that the same components as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

  The duct base 103 includes second fins 320 corresponding to the second fin group 120. The second fin 320 has a different shape from the second fin group 120 of the duct base 100 and is not divided. Further, in the duct base 100 according to the first embodiment, the arrangement pitch of the fin groups 110 and 120 in the direction orthogonal to the main flow direction is uniform. On the other hand, in the duct base 103, the arrangement pitch of the second fins 320 changes in the arrangement direction. Specifically, the distance between the adjacent second fins 320 is smaller as the distance from the fan drive shaft O is shorter. The arrangement pitch of the second fins 320 is gradually increased from the side closer to the fan drive shaft O, such as pitches p 3-1, p 3-2, p 3-3 and p 3-4. In addition, although the number of the 2nd fins 320 is five, it is not limited to this number. Other configurations of the duct base 103 are the same as those of the duct base 100.

  By configuring the arrangement pitch of the second fins 320 in this way, the air volume between the plurality of second fins 320 can be made uniform in the second heat radiation part F2 regardless of the distance from the air inlet 131. It becomes possible. As a result, the temperature of the main substrate 300 to be cooled can be made more uniform.

  According to the present embodiment, the same effects as those of the first embodiment can be obtained with respect to uniformizing the temperature of the substrate and the mounted component even if there is a calorific value distribution without increasing the size of the apparatus. it can. Moreover, even when the distribution of the heat generation amount in the second heat radiation part F2 is not uniform, the temperature of the heat radiation target can be made uniform.

  In addition, from the viewpoint of reducing the ventilation resistance, the second fin 320 provided in the second heat radiating portion F2 is not divided in the mainstream direction. However, as in the first embodiment, the second fin 320 is divided into a plurality in the mainstream direction. May be.

  In the first and second embodiments, the configuration in which the number of heat dissipating parts (flow paths) is two is illustrated, but the number of heat dissipating parts (flow paths) is three or more according to the distribution of heat sources that require heat dissipation. You may increase it. In that case, it is only necessary that two of the three or more heat radiating portions satisfy the relationship between the first heat radiating portion F1 and the second heat radiating portion F2 described in each embodiment. For example, at least the fins disposed in the heat radiating section with the shortest flow path length are preferably divided into a plurality in the main flow direction.

(Fourth embodiment)
In general, the imaging device may be used outdoors. When an imaging device is used during temporary outdoor photography, rainwater or the like may enter the inside of the device during stormy weather. Therefore, as a simple measure for preventing rainwater or the like from entering the imaging apparatus, the imaging apparatus may be covered with a rain cover using a waterproof material. At that time, if the ventilation hole of the imaging device for heat radiation is blocked by the rain cover, the heat radiation amount is lowered, and there is a concern that the device becomes abnormally high temperature. In particular, in a device including a fan, a force in the direction of being absorbed in the device by the intake air acts on the rain cover, so that the blockage of the ventilation path and the reduction of the heat radiation become more remarkable. In addition, since the periphery of the device is covered with a rain cover, smooth exhaust heat to the outside air by the fan is hindered, and some exhaust heat that has not been discharged to the outside air is between the rain cover and the exterior of the device. It stays in the space and promotes high temperature of the device. Furthermore, a part of the exhaust heat goes around to the intake side, thereby further increasing the temperature of the apparatus. As described above, there is a concern that the rain cover is attached to cause an increase in temperature of the apparatus. Therefore, in the fourth embodiment of the present invention, an accessory for an electronic device that can be attached to (detached from) the electronic device main body is provided. By attaching this accessory, the ventilation hole due to the rain cover is prevented from being blocked and the exhaust heat is prevented from flowing into the intake air. In the present embodiment, the imaging apparatus 1 described in the first embodiment is exemplified as an electronic device to which an accessory can be attached.

  FIGS. 15A and 15B are perspective views of accessories. The accessory 500 can be attached to and detached from the imaging apparatus 1, and FIGS. 15A and 15B show views from the inside and the outside of the imaging apparatus 1 when mounted on the imaging apparatus 1.

  The accessory 500 has a substantially flat base portion 550. A plurality of extending portions 510 (510a, 510b, 510c, 510d, 510f) are extended from the base portion 550 substantially vertically. In addition, the base portion 550 is formed with holding openings H5a and H5b that are through-holes side by side in the longitudinal direction of the base portion 550. In the mounting state on the imaging device 1, the longitudinal direction of the base portion 550 is the positive / negative direction of the Z axis, and the extending direction of the extending portion 510 is substantially parallel to the Y axis direction. Hereinafter, the direction in the accessory 500 is referred to based on the wearing state. In the extended portion 510, a mounting piece 520a extends from the edge on the Z axis negative direction side of the gripping opening H5a on the same side as the extended portion 510, and from the edge on the Z axis positive direction side of the grip opening H5b. The mounting piece 520b is extended on the same side as the extended portion 510. The attachment pieces 520a and 520b have elastic pieces 521a and 521b, respectively. The elastic pieces 521a and 521b are all elastically deformable in the Z-axis direction. Locking claws 522a and 522b are formed at the tips of the elastic pieces 521a and 521b, respectively.

  Furthermore, in the extended portion 510, a louver 530 that restricts the flow of wind is formed on the same side as the extended portion 510 from the edge of the gripping opening H5b on the Z axis negative direction side. In addition, from the end of the base portion 550 on the Z-axis negative direction side, a restricting portion 540 is formed so as to extend substantially parallel to the base portion 550 on the side opposite to the extending portion 510. The restricting portion 540 includes an elastic portion 541, and the elastic portion 541 is provided with a non-slip rib 543. The tip of the elastic part 541 is a bent guide part 542. The restricting portion 540 restricts the position of the end portion of the rain cover 600 by sandwiching the end portion of the rain cover 600 (FIG. 19) between the elastic portion 541 and the base portion 550. The anti-slip rib 543 prevents the attached rain cover 600 from being displaced. The guide part 542 guides the rain cover 600 between the elastic part 541 and the base part 550 when the rain cover 600 is attached. In the accessory 500, the above-described components are integrally formed by resin molding. In addition, parts other than the anti-slip rib 543 may be integrally formed in the accessory 500, and a member having higher elasticity than other parts may be used for the anti-slip rib 543.

  Next, a method for attaching the accessory 500 to the imaging apparatus 1 and an operation after the attachment will be described with reference to FIGS. FIG. 16 is a diagram of the imaging apparatus 1 with the accessory 500 mounted as viewed from the front, and a part thereof is shown in cross section. FIG. 17 is a detailed view of part B of FIG. Two accessories 500 having the same configuration are prepared and can be mounted on either the left side or the right side of the imaging apparatus 1. The accessory 500 has a fixed vertical orientation when mounted, and is mounted so that the tip of the extended portion 510 faces the imaging device 1 side.

  As shown in FIG. 16, one accessory 500 is detachably attached to the intake side duct cover 5 and the exhaust side duct cover 6 respectively. Here, description will be given focusing on the accessory 500 attached to the exhaust side duct cover 6. In addition, since the attachment method to the intake side duct cover 5 and an effect | action are the same, some description is abbreviate | omitted. At the time of mounting on the imaging device 1, the user holds the elastic pieces 521 a and 521 b after positioning the accessory 500 so that the respective distal end portions of the extending portions 510 match the outer shape of the exhaust duct cover 6. At that time, the user can operate the elastic pieces 521a and 521b through the fingers through the gripping openings H5a and H5b to elastically deform them in a direction approaching each other.

  Incidentally, each of the intake side duct cover 5 and the exhaust side duct cover 6 includes a plurality of ribs along the optical axis direction, and a slit is formed between adjacent ribs. A plurality of slits constitute each ventilation hole. For example, as shown in FIG. 17, the exhaust side duct cover 6 has ribs 61 and slits 62, and the plurality of slits 62 constitute an exhaust side ventilation hole (external exhaust port 60; FIG. 1B). To do. Although the intake duct cover 5 is not illustrated, a plurality of slits similarly form intake-side ventilation holes (external intake ports 51 and 52; FIG. 1 (a)).

  As shown in FIG. 17, the user inserts the locking claws 522a and 522b into the corresponding slits 62 of the exhaust side duct cover 6, and locks the locking claws 522a and 522b to the ribs 61 at the corresponding positions. To do. Although FIG. 17 shows only the locking claw 522b, the locking mode of the upper locking claw 522a is the same. Thus, the upper and lower two locking claws 522 a and 522 b are locked to the corresponding ribs 61, so that the accessory 500 is held against the exhaust duct cover 6 and attached to the imaging device 1. The Since each finger can be inserted into the gripping openings H5a and H5b, it is easy to grip and operate the elastic pieces 521a and 521b, and the operability when the accessory 500 is mounted is high. To remove the accessory 500, the engagement between the locking claws 522a and 522b and the rib 61 may be released. Since the accessory 500 can be easily attached to and detached from the duct cover on the intake side and the exhaust side, when the rain cover 600 is not used, the accessory 500 can be removed to avoid an increase in the size of the entire apparatus.

  In a state where the accessory 500 is attached to each of the intake side duct cover 5 and the exhaust side duct cover 6, the base portions 550 are substantially parallel to the corresponding duct covers and face the corresponding ventilation holes. Moreover, each of the base portions 550 is located at a position separated from the device and the ventilation holes by the extending portion 510. That is, the extended portion 510 abuts on the exhaust side duct cover 6 so that a gap E is formed between the extended portion 510 and the base portion 550 (FIG. 16). Similarly, a gap E is also formed between the intake duct cover 5 and the base portion 550. Furthermore, an opening L4d is formed between the extended portions 510c and 510f and the exhaust side duct cover 6 on the exhaust side. On the intake side, an opening R4d is formed between the extending portions 510c and 510f and the intake-side duct cover 5. The openings L4d and R4d are opened substantially vertically below the electronic device. The openings L4d and R4d are connected to the corresponding gap E. Therefore, when the accessory 500 is attached, the extending portion 510 is in contact with the imaging device 1, so that a gap E is secured between the base portion 550 and the corresponding ventilation hole. Furthermore, openings L4d and R4d connected to (communicating with) the gap E are formed between the extending portions 510c and 510f, the base portion 550, and the imaging device 1 (particularly the duct cover). Therefore, on the intake side and the exhaust side, the extending portion 510 abuts on the imaging device 1, and openings (L4d, R4d) connected to the outside air from the ventilation holes are formed between the imaging device 1 and the base portion 550. The

  Next, the intake / exhaust path when the rain cover is attached will be described. Intake air w3 and exhaust air w4 shown in FIG. 16 schematically represent the flow of intake air and exhaust air by driving the fan 130 when the rain cover is mounted. The louver 530 regulates the flow of wind so as to form a flow path between the corresponding ventilation hole and the opening (L4d, R4d). The intake air w3 is taken in from the opening R4d and travels substantially parallel to the intake-side duct cover 5, and then passes through the gap E to the ventilation holes of the intake-side duct cover 5 (the first external intake 51 and the second external The air enters from the air inlet 52). On the other hand, the exhaust air w4 exits the exhaust duct cover 6 in a substantially vertical direction and proceeds to the gap E, and then the traveling direction is regulated in the negative Z-axis direction by the action of the louver 530 and flows out from the opening L4d to the outside air. To do.

  FIGS. 18A and 18B are perspective views of the imaging device 1 with the accessory 500 mounted, as viewed from above and below, respectively. Assume that one accessory 500 is attached to each of the intake side duct cover 5 and the exhaust side duct cover 6. 18 and 19, the accessory 500 attached to the intake side duct cover 5 will be mainly described in detail. However, the same applies to the exhaust side duct cover 6 side, and the description thereof will be omitted as appropriate.

  As described above, when the accessory 500 is attached, the gap E (FIG. 16) is formed by the extended portion 510 and the like. In addition, openings R4 (R4a, R4b, R4c) are formed on four surfaces in the front-rear and vertical directions that are surrounded by the intake-side duct cover 5, the extending portion 510, and the base portion 550 and that are perpendicular to the intake-side duct cover 5. , R4d) are formed (see also FIG. 16 for the opening R4d). Similarly, the exhaust side duct cover 6 side is also surrounded by the extending portion 510 and the base portion 550 and has openings L4 on four surfaces in the front and rear and vertical directions perpendicular to the exhaust side duct cover 6. It is formed. For the opening L4, only the openings L4a and L4d are indicated by reference numerals (see also FIG. 16 for the opening L4d). These openings prevent the first external intake port 51, the second external intake port 52, and the external exhaust port 60 (FIGS. 1A and 1B) from being blocked due to the rain cover 600 being attached, so that ventilation is possible. It is possible to prevent a decrease in the amount. The total area of the plurality of openings R4 is equal to or greater than the total area of the first external intake port 51 and the second external intake port 52. The total area of the plurality of openings L4 is equal to or greater than the area of the external exhaust port 60. As a result, an increase in ventilation resistance due to the attachment of the accessory 500 is suppressed.

  FIG. 19 is a perspective view of the imaging apparatus 1 with the accessory 500 and the rain cover 600 attached as viewed from below (Z-axis negative direction). The user puts the rain cover 600 on the imaging device 1 as desired. The rain cover 600 covers the periphery of the image pickup apparatus 1 except for the bottom surface portion, and prevents rainwater or the like from entering the image pickup apparatus 1 from above (in the positive Z-axis direction) or from the side.

  Next, a method for attaching the rain cover 600 to the imaging device 1 will be described. The rain cover 600 covers the periphery of the interchangeable lens 2 and then covers the exterior of the imaging device 1 and the base portion 550 of the accessory 500 from above. The end portion of the rain cover 600 is guided between the elastic portion 541 and the base portion 550 by the guide portion 542 provided in the restriction portion 540. Here, the elastic portion 541 is elastically deformed to sandwich the end portion of the rain cover 600. Further, the slippage of the rain cover 600 is suppressed by the anti-slip ribs 543 (FIG. 15A). The user restricts the rain cover 600 with a pair of Velcro (registered trademark) 601 after restricting the end portions (positions in the vicinity of the openings R4d and L4d) of the rain cover 600 with the restricting portion 540.

  As described above, the position of the end portion of the rain cover 600 is restricted by the restriction portion 540, so that the opening portions R4d and L4d below the imaging device 1 are blocked. Intake by the drive of the fan 130 flows from the plurality of openings R4, but the opening R4d is not covered by the rain cover 600, and the ventilation resistance is relatively low. Therefore, a lot of intake air flows from the opening R4 (intake air w3). On the other hand, the exhaust is discharged from the plurality of openings L4, but the opening L4d is not covered with the rain cover 600 and has relatively low ventilation resistance. Moreover, a main flow path from the external exhaust port 60 to the opening L4d is easily formed by the function of the louver 530. Therefore, a lot of exhaust gas is discharged from the opening L4d to the outside air (exhaust air w4).

  In this way, it is possible to avoid stagnation of exhaust heat in the minute space between the rain cover 600 and the imaging device 1. Thereby, the wraparound of the exhaust heat to the intake side is suppressed, and the intake / exhaust path can be clearly divided. As a result, in a state in which the rain cover 600 is attached, after the low temperature outside air is mainly taken into the first unit 1001 from the opening R4d and the heat of the imaging device 1 is taken away, the heat is mainly discharged from the opening L4d to the outside air. A heat dissipation path can be formed.

  According to the present embodiment, when the accessory 500 is attached to the imaging apparatus 1, the gap 510 is formed by the extending portion 510 and the openings L4d and R4d connected to the gap E are formed. The openings L4d and R4d connect the ventilation holes (external exhaust port 60, external intake ports 51 and 52) and the outside air. If the accessory 500 is attached, even if the rain cover 600 is put on the imaging apparatus 1, the end portions of the rain cover 600 are restricted by the restricting portion 540, thereby closing the openings L4d and R4d. Is suppressed. Thereby, the heat dissipation efficiency of the imaging device 1 can be improved. In particular, even in a state in which the image capturing apparatus 1 is covered, it is possible to ensure ventilation and maintain a heat dissipation function.

  Further, the louver 530 regulates the flow of wind so as to form a flow path between the ventilation holes (external exhaust port 60, external intake ports 51 and 52) and the openings L4d and R4d. Further, the total area of the opening R4 is equal to or greater than the total area of the external intake ports 51 and 52, and the total area of the opening L4 is equal to or greater than the area of the external exhaust port 60. Even if the accessory 500 is attached, an increase in ventilation resistance is suppressed. As a result, intake / exhaust becomes smooth and contributes to ensuring heat dissipation efficiency.

  Moreover, since the rib 61 which comprises a ventilation hole becomes an attaching part to which the accessory 500 is attached, it does not need to increase a number of parts. In addition, the user can operate the attachment pieces 520 a and 520 b through the fingers through the grip openings H <b> 5 a and H <b> 5 b formed in the base portion 550, and the engagement claws 522 a and 522 b of the attachment pieces 520 a and 520 b are engaged with the rib 61. Thus, the accessory 500 can be attached. Thus, the operation of attaching and removing the accessory 500 is easy.

  Further, the accessory 500 has no distinction between right and left, and can be used for both intake and exhaust, so that it is not necessary to increase the types of accessories 500.

  In addition, the accessory 500 of this Embodiment is applicable to the electronic device of 1st, 2nd, 3rd Embodiment, and the kind of applied electronic device is not ask | required.

  Although the present invention has been described in detail based on preferred embodiments thereof, the present invention is not limited to these specific embodiments, and various forms within the scope of the present invention are also included in the present invention. included. A part of the above-described embodiments may be appropriately combined.

DESCRIPTION OF SYMBOLS 100 Duct base 110 1st fin group 120 2nd fin group 130 Fan 140 Duct cover 300 Main board F1 1st thermal radiation part F2 2nd thermal radiation part

In order to achieve the above object, the present invention provides an imaging unit including an imaging device, a circuit board that performs image processing on the output of the imaging unit, and heat generated in the circuit board A duct part and a back member disposed at the rear of the apparatus in the optical axis direction and constituting a part of the exterior, and the circuit board is disposed between the duct part and the back member in the optical axis direction. The duct portion is provided with a plurality of extending portions extending in the optical axis direction and in contact with the back member.

Claims (29)

A fan having an air inlet;
A duct portion having an opening corresponding to the air inlet of the fan;
A circuit board connected to the duct part and arranged to be laminated on the opposite side of the fan with respect to the duct part;
A first cover that is disposed on the side opposite to the fan with respect to the circuit board and constitutes a part of an exterior;
A second cover constituting a part of the exterior in a direction substantially perpendicular to the stacking direction of the duct part and the circuit board,
The duct portion includes a plurality of first extending portions extending so as to surround the circuit board, and a second extending portion extending in a direction substantially perpendicular to the stacking direction,
The first extending portion is fixed to the first cover, and the second extending portion is fixed to the second cover.   The electronic device according to claim 1, wherein the second cover is disposed on a bottom surface side of the electronic device.   The electronic device according to claim 1, wherein the second cover is disposed on an upper surface side of the electronic device. A substantially U-shaped third cover that covers the duct portion from above and from the side;
The electronic device according to claim 2, wherein the third cover is disposed so as to sandwich the duct portion from the left-right direction.   The electronic device according to claim 1, wherein the first cover is made of a metal material.   6. The electronic device according to claim 1, wherein an escape portion for avoiding interference with the first extending portion is formed on the circuit board. The duct portion includes a first heat radiating portion and a second heat radiating portion in which fins substantially parallel to the main flow direction are respectively disposed, and an opening corresponding to the air intake port of the fan,
The flow path length of the second heat dissipation part is longer than the flow path length of the first heat dissipation part,
Of the fins disposed in the first and second heat radiating portions, at least the fins disposed in the first heat radiating portion are divided into a plurality in the mainstream direction,
The number of fins per unit length in the main flow direction is greater in the number of fins disposed in the first heat dissipation portion than in the fins disposed in the second heat dissipation portion. The electronic device according to any one of 1 to 5. The fins disposed in the first heat radiating portion and the fins disposed in the second heat radiating portion are each arranged in parallel,
The electronic device according to claim 7, wherein the pitch of the fins disposed in the second heat radiating portion is larger than the pitch of the fins disposed in the first heat radiating portion. A plurality of fins arranged in the second heat radiating portion are arranged in parallel,
The electronic device according to claim 7, wherein the pitch of the fins disposed in the second heat radiating portion is smaller as the distance from the center of the opening is shorter.   The area of the intake opening corresponding to the first heat radiating portion in the duct portion is larger than the area of the intake opening corresponding to the second heat radiating portion. The electronic device as described in the paragraph.   11. The electronic apparatus according to claim 7, wherein the flow path of the first heat radiating portion has a substantially linear shape.   12. The electronic apparatus according to claim 11, wherein the flow path of the second heat radiating portion has a substantially bent shape.   Of the fins disposed in the first heat radiating portion, the length of the fin closest to the intake opening corresponding to the first heat radiating portion in the duct portion is adjacent to the fin in the mainstream direction. The electronic device according to claim 7, wherein the electronic device is longer than the length of the electronic device. The fins disposed in the second heat radiating portion are divided into a plurality of mainstream directions,
In the fin disposed in the second heat radiating portion, the length of the fin closest to the intake opening corresponding to the second heat radiating portion in the duct portion is the length of the fin adjacent to the fin in the main flow direction. The electronic apparatus according to claim 7, wherein the electronic apparatus is longer than the length.   The electronic device according to claim 7, wherein the opening and the fan are each single.   The one part of several fins divided | segmented in the said 1st thermal radiation part exists in a part of area | region facing the said opening part, The any one of Claims 7 thru | or 15 characterized by the above-mentioned. The electronic device described.   Of the fins disposed in the first heat radiating portion, the protruding height of the fin existing in the region facing the opening is lower than the protruding height of the fin existing in the region not facing the opening. The electronic device according to claim 16, characterized in that:   The electronic device according to claim 1, wherein the fan is a centrifugal fan.   An imaging apparatus comprising the electronic device according to claim 1. An accessory that can be attached to the mounting portion of an electronic device having a fan, a vent hole, and a mounting portion,
A base portion facing the ventilation hole in a mounting state in which the accessory is mounted on the mounting portion;
An extending portion that extends from the base portion, contacts the electronic device in the mounted state, and forms an opening connected to the outside air from the ventilation hole between the electronic device and the base portion;
An accessory comprising: a restricting portion that restricts the position of the end portion of the cover placed on the electronic device from being blocked by the cover.   21. The accessory according to claim 20, wherein the opening portion opens substantially vertically below the electronic device.   The accessory according to claim 20 or 21, further comprising a louver that regulates a flow of wind so as to form a flow path between the ventilation hole and the opening. At least one opening is formed,
The accessory according to any one of claims 20 to 22, wherein a total area of the at least one opening is equal to or larger than an area of the ventilation hole. The ventilation hole has a plurality of slits formed by a plurality of ribs,
The accessory according to any one of claims 20 to 23, wherein at least a part of the plurality of ribs serves as the attachment portion.   25. The accessory according to claim 24, further comprising a locking claw, wherein the accessory is attached to the attachment portion by the locking claw being locked to the rib.   The accessory according to any one of claims 20 to 25, wherein a through hole is formed in the base portion.   27. The accessory according to claim 26, wherein at least two through holes are formed for gripping the accessory.   The accessory according to any one of claims 20 to 27, wherein the restricting portion is formed integrally with the base portion.   The accessory according to claim 22, wherein the louver is formed integrally with the base portion.

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