JP2012069902A - Radiating structure, and electronic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the radiating property of heat generated in an electronic component, and to reduce influences due to electromagnetic noise.SOLUTION: A radiating structure comprises a circuit substrate 13 which is disposed in an outer housing 2, has a component mounting portion 17 and ground portions 13c and 13d connected to a ground circuit, and is mounted with an electronic component 18 functioning as a heat source during driving on one surface of the component mounting portion; a heatsink 14 which is disposed on a surface side on which the electronic component of the circuit substrate is mounted, and emits heat generated in the electronic component; a radiating plate 16 which is disposed on the opposite side to the side on which the electronic component is mounted over the circuit substrate, and has a platy base portion 16a and a projecting portion 16b projected out to the circuit substrate side from the base portion and formed with an opposite surface 16c opposing to the other surface of the component mounting portion; and a first heat transmission body 23 which is stuck to the other surface of the component mounting portion of the circuit substrate and the opposite surface in the projecting portion of the radiating plate, and transmits heat generated in the electronic component to the radiating plate.

Description

  The present invention relates to the technical field of heat dissipation structures and electronic devices. More specifically, the present invention relates to a technical field in which a heat radiating plate having a protruding portion is arranged on the side opposite to the side on which an electronic component is mounted on a circuit board to improve heat dissipation related to heat generated in the electronic component and reduce the influence of electromagnetic noise.

  A predetermined wiring pattern is formed in the outer casing of various electronic devices such as a recording medium recording / reproducing device, a sound recording / reproducing device, a mobile phone, an image recording / reproducing device, an imaging device, an information processing device, and a network communication device. Many circuit boards are arranged.

  Electronic components having various functions are mounted on such a circuit board, and the electronic components generate heat during driving. Since the heat generated in the electronic component may adversely affect the operation of the electronic device, the electronic device is provided with a heat dissipation structure for suppressing a temperature rise due to the generated heat (for example, Patent Document 1). And Patent Document 2).

  On the other hand, in an electronic device, as described above, a predetermined wiring pattern is formed on a circuit board and an electronic component is mounted, and electromagnetic waves are generated from these wiring patterns and the generated electromagnetic waves are regarded as electromagnetic noise. May adversely affect the operation of electronic devices. In particular, in order to ensure high heat dissipation, a metal member such as a heat sink or a heat radiating plate is disposed in the vicinity of the electromagnetic wave source, and if the area is large, the electromagnetic wave is easily coupled to the metal member. The effect of noise will increase.

JP 2003-234585 A JP-A-10-163581

  In the electronic devices described in Patent Document 1 and Patent Document 2, an electronic component or a circuit board on which the electronic component is mounted is provided with a heat conduction portion integrally provided in a chassis configured as a part of the outer casing. Heat is dissipated by contacting the component mounting part, and heat is dissipated from the outer casing.

  However, in the electronic devices described in Patent Document 1 and Patent Document 2, the heat dissipation structure is configured in consideration of ensuring high heat dissipation performance. However, the heat radiating structure is not configured in order to achieve both the improvement of heat dissipation and the reduction of the influence of electromagnetic noise.

  Accordingly, it is an object of the present invention to overcome the above-described problems and to improve heat dissipation related to heat generated in electronic components and reduce the influence of electromagnetic noise.

  In order to solve the above-described problems, the heat dissipating structure has a component mounting portion and a ground portion connected to a grounding circuit, and is disposed on one surface of the component mounting portion. A circuit board on which the electronic component to be mounted is mounted, a heat sink that is disposed on the surface side of the circuit board on which the electronic component is mounted, and that releases heat generated in the electronic component, and the electronic component across the circuit board Are disposed on the side opposite to the side on which the component is mounted, and has a flat plate-like base portion and a protruding portion that protrudes from the base portion to the circuit board side and that faces the other surface of the component mounting portion. And a heat sink that is in close contact with the other surface of the component mounting portion of the circuit board and the opposing surface of the protruding portion of the heat sink and transmits heat generated in the electronic component to the heat sink. 1's It is obtained by a transfer member.

  Accordingly, in the heat dissipation structure, the component mounting portion of the circuit board and the protrusion of the heat sink are brought into contact with each other via the first heat transfer body, and the base portion of the heat sink is positioned away from the circuit board. The

  In the heat dissipation structure described above, the heat dissipation surface portion is disposed between the circuit board and the heat sink and has a flat heat dissipation surface portion and a mounted protrusion protruding from the heat dissipation surface portion. A heat spreader in close contact with a heat sink; and a second heat transfer body that is in close contact with the other surface of the heat spreader and the electronic component and transmits heat generated in the electronic component to the heat spreader and the heat sink. It is desirable that the mounting protrusion of the heat spreader is attached to the ground portion of the circuit board.

  By attaching the attachment protrusion of the heat spreader to the ground portion of the circuit board, the attachment portion is connected to the ground circuit via the ground portion.

  In the heat dissipation structure described above, a part of the outer casing is configured by a chassis made of a metal material and having a coupling portion, the radiator plate is attached to the chassis, and the coupling portion of the chassis is coupled to the ground portion of the circuit board. It is desirable to do.

  By coupling the coupling portion of the chassis to the ground portion of the circuit board, the coupling portion is connected to the ground circuit through the ground portion.

  In the above heat dissipation structure, it is desirable that the distance between the facing surface of the protrusion of the heat dissipation plate and the circuit board is 1.2 mm or more.

  By setting the distance between the facing surface of the projecting portion of the heat sink and the circuit board to be 1.2 mm or more, the far field strength is reduced.

  In the heat dissipation structure described above, it is desirable to attach a resin sheet having a heat dissipation hole on a surface opposite to the surface facing the circuit board in the base portion of the heat dissipation plate.

  A resin sheet is disposed on the outer surface side of the base portion by attaching a resin sheet having a heat radiating hole to the surface of the base portion of the heat radiating plate opposite to the surface facing the circuit board.

  In the heat dissipation structure described above, an insertion hole may be formed in the chassis, a base portion of the heat dissipation plate may be attached to the outer surface of the chassis, and a protruding portion of the heat dissipation plate may be inserted into the insertion hole of the chassis. desirable.

  By forming the insertion hole in the chassis, attaching the base part of the heat sink to the outer surface of the chassis, and inserting and arranging the protrusion part of the heat sink in the insertion hole of the chassis, the base part of the heat sink is placed on the outer surface side of the chassis Be placed.

  In the heat dissipation structure described above, the placement recess is formed in the chassis, the insertion hole is formed at a position passing through a part of the placement recess, the base portion of the heat dissipation plate is placed in the placement recess, and the insertion hole It is desirable to insert and arrange the protrusion part of the said heat sink.

  A placement recess is formed in the chassis, an insertion hole is formed at a position penetrating a part of the placement recess, a base portion of the heat sink is placed in the placement recess, and a protrusion of the heat sink is inserted into the insertion hole. Thereby, it arrange | positions in the state which a base part does not protrude outward from the outer surface of a chassis.

  In the heat dissipation structure described above, it is preferable that a resin sheet having a heat dissipation hole is attached to a surface of the base portion of the heat dissipation plate opposite to the surface facing the circuit board, and the resin sheet is disposed in the arrangement recess.

  By attaching a resin sheet having a heat dissipation hole on the surface of the base of the heat sink opposite to the surface facing the circuit board, and placing the resin sheet in the placement recess, the resin sheet does not protrude outward from the outer surface of the chassis. Arranged in a state.

  In order to solve the above-described problems, an electronic device includes an outer casing in which predetermined parts are arranged, and a ground part that is arranged in the outer casing and is connected to a component mounting unit and a ground circuit. A circuit board on which an electronic component serving as a heat source during driving is mounted on one surface of the component mounting portion, and heat generated in the electronic component disposed on the surface side of the circuit board on which the electronic component is mounted A heat sink to be emitted, a flat base portion disposed on the side opposite to the side on which the electronic component is mounted across the circuit board, and the other of the component mounting portion projecting from the base portion to the circuit board side A heat sink having a projecting portion formed with a facing surface facing the surface, the other surface of the component mounting portion of the circuit board and the facing surface of the projecting portion of the heat sink and Electronic component smell It is obtained by a first heat transfer member for transmitting the generated heat to the heat radiating plate.

  Therefore, in the electronic device, the component mounting part of the circuit board and the protruding part of the heat sink are brought into contact with each other via the first heat transfer body, and the base part of the heat sink is positioned away from the circuit board. The

  Another heat dissipating structure has a component mounting portion and a ground portion connected to a ground circuit, and is driven on one surface of the component mounting portion in order to solve the above-described problems. A circuit board on which an electronic component that is sometimes a heat source is mounted; and a plate-like base portion that is disposed on the surface side of the circuit board on which the electronic component is mounted and projects from the base portion to the circuit board side. A first heat radiating plate having a protruding portion formed with an opposing surface facing one surface of the component mounting portion; the one surface of the component mounting portion of the circuit board; and a protruding portion of the first heat radiating plate. And a first heat transfer body for transferring heat generated in the electronic component to the first heat radiating plate.

  Therefore, in another heat dissipation structure, the component mounting portion of the circuit board and the protruding portion of the first heat dissipation plate are in contact with each other via the first heat transfer body, and the base portion of the first heat dissipation plate is Located away from the circuit board.

  In the heat dissipation structure described above, it is preferable that a mounting protrusion is provided on the first heat dissipation plate, and the mounting protrusion of the first heat dissipation plate is attached to the ground portion of the circuit board.

  By providing a mounting protrusion on the first heat radiating plate and mounting the mounting protrusion on the first heat radiating plate to the ground portion of the circuit board, the mounting portion is connected to the ground circuit via the ground portion.

  In the above heat dissipation structure, it is desirable that the distance between the facing surface of the protruding portion of the first heat dissipation plate and the circuit board is 1.2 mm or more.

  By setting the distance between the facing surface of the projecting portion of the first heat radiating plate and the circuit board to be 1.2 mm or more, the far field strength is reduced.

  In the above heat dissipation structure, the component mounting portion is disposed on the side opposite to the side on which the electronic component is mounted across the circuit board and protrudes from the base portion to the circuit board side. A second heat radiating plate having a projecting portion formed with a facing surface facing the other surface of the circuit board, and the facing of the other surface of the component mounting portion of the circuit board and the projecting portion of the second heat radiating plate. It is desirable to provide a second heat transfer body that is in close contact with a surface and transmits heat generated in the electronic component to the second heat radiating plate.

  The component mounting portion of the circuit board is provided via the first heat transfer body by providing a second heat radiating plate disposed on the opposite side to the side on which the electronic component is mounted across the circuit board and having a base portion and a protruding portion. And the projecting portion of the first heat radiating plate are brought into contact with each other, the component mounting portion of the circuit board and the projecting portion of the second heat radiating plate are brought into contact with each other through the second heat transfer body, and the first heat radiating plate and the first heat radiating plate Each base part of 2 heat sinks is located apart from the circuit board.

  In the above heat dissipation structure, a part of the outer casing is formed of a chassis made of a metal material and having a coupling portion, the second heat radiation plate is attached to the chassis, and the coupling portion of the chassis is connected to the ground of the circuit board. It is desirable to couple to the part.

  By coupling the coupling portion of the chassis to the ground portion of the circuit board, the coupling portion is connected to the ground circuit through the ground portion.

  In the above heat dissipation structure, it is desirable that the distance between the facing surface of the protruding portion of the second heat dissipation plate and the circuit board is 1.2 mm or more.

  When the distance between the facing surface of the projecting portion of the second heat radiating plate and the circuit board is set to 1.2 mm or more, the far field strength is reduced.

  In the heat dissipation structure described above, it is desirable to attach a resin sheet having a heat dissipation hole on the surface opposite to the surface facing the circuit board in the base portion of the second heat dissipation plate.

  The resin sheet is disposed on the outer surface side of the base portion by attaching the resin sheet having the heat radiation holes to the surface opposite to the surface facing the circuit board in the base portion of the second heat radiating plate.

  In the above heat dissipation structure, an insertion hole is formed in the chassis, a base portion of the second heat dissipation plate is attached to an outer surface of the chassis, and a protruding portion of the second heat dissipation plate is inserted into the insertion hole of the chassis. It is desirable to arrange them.

  An insertion hole is formed in the chassis, a base portion of the second heat sink is attached to the outer surface of the chassis, and a protruding portion of the second heat sink is inserted into the insertion hole of the chassis and arranged on the outer surface side of the chassis. A base portion of the second heat radiating plate is disposed.

  In the heat dissipation structure described above, an arrangement recess is formed in the chassis, the insertion hole is formed at a position penetrating a part of the arrangement recess, the base portion of the second heat dissipation plate is arranged in the arrangement recess, It is desirable that the protruding portion of the second heat radiating plate is inserted and disposed in the insertion hole.

  A placement recess is formed in the chassis, an insertion hole is formed at a position penetrating a part of the placement recess, a base portion of the second heat sink is placed in the placement recess, and a protrusion of the second heat sink is inserted into the insertion hole. By inserting and arranging, the base portion is arranged without protruding outward from the outer surface of the chassis.

  In the heat dissipation structure described above, a resin sheet having a heat dissipation hole is attached to a surface opposite to the surface facing the circuit board in the base portion of the second heat dissipation plate, and the resin sheet is disposed in the arrangement recess. Is desirable.

  A resin sheet having a heat radiation hole is attached to a surface of the base portion of the second heat radiating plate opposite to the surface facing the circuit board, and the resin sheet is disposed in the arrangement recess so that the resin sheet is outward from the outer surface of the chassis. It is arranged in a state that does not protrude.

  In order to solve the above-described problems, another electronic device includes an outer casing in which predetermined parts are arranged, and a ground unit that is arranged in the outer casing and connected to a component mounting unit and a ground circuit. A circuit board on which one of the component mounting portions is mounted with an electronic component that is a heat source during driving, and a flat base that is disposed on the surface of the circuit board on which the electronic component is mounted And a first heat radiating plate having a protruding portion formed from the base portion and projecting from the base portion to the circuit board side and opposed to one surface of the component mounting portion, and a component mounting portion of the circuit board And a first heat transfer body that is in close contact with the one surface and the facing surface of the protruding portion of the heat radiating plate and transmits heat generated in the electronic component to the heat radiating plate.

  Therefore, in another electronic device, the component mounting portion of the circuit board and the protruding portion of the first heat radiating plate are brought into contact with each other via the first heat transfer body, and the base portion of the first heat radiating plate is Located away from the circuit board.

  The heat dissipating structure of the present invention has a component mounting portion and a ground portion connected to a ground circuit, and an electronic component that is a heat source during driving is mounted on one surface of the component mounting portion. A circuit board, a heat sink that is disposed on the surface side of the circuit board on which the electronic component is mounted, and that releases heat generated in the electronic component, and is opposite to the side on which the electronic component is mounted across the circuit board A heat radiating plate having a flat base portion and a projecting portion formed from the base portion and projecting from the base portion to the circuit board side and facing the other surface of the component mounting portion; A first heat transfer body that is in close contact with the other surface of the component mounting portion of the circuit board and the opposing surface of the protruding portion of the heat dissipation plate and that transfers heat generated in the electronic component to the heat dissipation plate; I have.

  Therefore, the projecting part of the heat sink is connected to the circuit board through the heat transfer body and the base part is located away from the circuit board. Can be reduced.

  In the invention described in claim 2, the heat dissipating surface portion includes a flat heat dissipating surface portion and a mounting protrusion protruding from the heat dissipating surface portion and disposed between the circuit board and the heat sink. A heat spreader having one surface in close contact with the heat sink, and a second surface that is in close contact with the other surface of the heat spreader and the electronic component and transmits heat generated in the electronic component to the heat spreader and the heat sink. A heat transfer body, and the attached protrusion of the heat spreader is attached to the ground portion of the circuit board.

  Therefore, since the mounted protrusion of the heat spreader is connected to the ground circuit via the ground portion, the influence of electromagnetic noise can be reduced.

  According to a third aspect of the present invention, a part of the outer casing is constituted by a chassis made of a metal material and having a coupling portion, the heat radiating plate is attached to the chassis, and the coupling portion of the chassis is connected to the circuit board. It is connected to the ground part.

  Therefore, since the coupling portion of the chassis is connected to the ground circuit via the ground portion, the influence of electromagnetic noise can be reduced.

  In the invention described in claim 4, the distance between the facing surface of the projecting portion of the heat sink and the circuit board is set to 1.2 mm or more.

  Therefore, the influence of electromagnetic noise can be further reduced.

  In the invention described in claim 5, a resin sheet having a heat radiation hole is attached to a surface opposite to the surface facing the circuit board in the base portion of the heat radiation plate.

  Therefore, fingers do not come into contact with the heat dissipation plate during heat dissipation, and it is possible to improve safety such as prevention of burns after improving heat dissipation.

  In the invention described in claim 6, an insertion hole is formed in the chassis, a base portion of the heat radiating plate is attached to an outer surface of the chassis, and a protruding portion of the heat radiating plate is inserted into the insertion hole of the chassis. Arranged.

  Accordingly, since the base portion of the heat radiating plate is disposed on the outer surface side of the chassis, the heat generated in the electronic component can be efficiently released to the outside, and the heat dissipation can be further improved.

  In the invention described in claim 7, a placement recess is formed in the chassis, the insertion hole is formed at a position penetrating a part of the placement recess, and the base portion of the heat sink is placed in the placement recess. And the protrusion part of the said heat sink is inserted and arrange | positioned in the said insertion hole.

  Therefore, the heat radiating plate does not protrude outward from the outer surface of the chassis, and the heat radiating structure can be reduced in size while improving the heat radiating property and the safety.

  In the invention described in claim 8, a resin sheet having a heat radiating hole is attached to a surface of the base portion of the heat radiating plate opposite to the surface facing the circuit board, and the resin sheet is disposed in the arrangement recess. is doing.

  Therefore, the resin sheet does not protrude outward from the outer surface of the chassis, and the heat dissipation structure can be downsized while ensuring good heat dissipation.

  The electronic apparatus according to the present invention includes an outer casing in which predetermined parts are disposed, and a component mounting unit and a ground unit that is disposed in the outer casing and connected to a ground circuit. A circuit board on which an electronic component serving as a heat source during driving is mounted on one surface, a heat sink disposed on the surface side of the circuit board on which the electronic component is mounted, and releasing heat generated in the electronic component; and the circuit A plate-like base portion and a facing surface that protrudes from the base portion to the circuit board side and faces the other surface of the component mounting portion are disposed on the side opposite to the side on which the electronic component is mounted across the substrate. A heat sink having a protrusion formed thereon, and the heat generated in the electronic component while being in close contact with the other surface of the component mounting portion of the circuit board and the facing surface of the protrusion of the heat sink. Heat sink And a first heat transfer member for transferring.

  Therefore, the projecting part of the heat sink is connected to the circuit board through the heat transfer body and the base part is located away from the circuit board. Can be reduced.

  Another heat dissipating structure of the present invention has a component mounting portion and a ground portion connected to a ground circuit and disposed on the inside of the outer casing in order to solve the above-described problem. A circuit board on which an electronic component that is a heat source during driving is mounted, a surface of the circuit board on which the electronic component is mounted, and a flat base portion that protrudes from the base portion to the circuit board side A first heat radiating plate having a protruding portion formed with an opposing surface facing one surface of the component mounting portion, the one surface of the component mounting portion of the circuit board, and the first heat radiating plate. And a first heat transfer body that is in close contact with the facing surface of the projecting portion and transmits heat generated in the electronic component to the first heat radiating plate.

  Accordingly, since the protruding portion of the first heat radiating plate is connected to the circuit board via the first heat transfer body and the base portion is located away from the circuit board, the heat radiating property of the heat generated in the electronic component can be reduced. Improvement and reduction of the influence by electromagnetic noise can be aimed at.

  In the invention described in claim 11, a mounting protrusion is provided on the first heat radiating plate, and the mounting protrusion of the first heat radiating plate is mounted on the ground portion of the circuit board.

  Therefore, since the attachment protrusion of the first heat radiating plate is connected to the ground circuit via the ground portion, the influence of electromagnetic noise can be reduced.

  In a twelfth aspect of the invention, the distance between the facing surface of the projecting portion of the first heat radiating plate and the circuit board is set to 1.2 mm or more.

  Therefore, the influence of electromagnetic noise can be further reduced.

  In a thirteenth aspect of the present invention, the electronic circuit board is disposed on a side opposite to the side on which the electronic component is mounted with the circuit board interposed therebetween, and the flat base portion and the base portion protrude from the base portion. A second heat radiating plate having a protruding portion formed with a facing surface facing the other surface of the component mounting portion, the other surface of the component mounting portion of the circuit board, and the second heat radiating plate. A second heat transfer body is provided which is in close contact with the facing surface of the protrusion and transmits heat generated in the electronic component to the second heat radiating plate.

  Therefore, heat is released from both the first heat radiating plate and the second heat radiating plate when the electronic component generates heat, and high heat dissipation can be ensured.

  In the invention described in claim 14, a part of the outer casing is configured by a chassis made of a metal material and having a coupling portion, the second heat radiating plate is attached to the chassis, and the coupling portion of the chassis is formed. The circuit board is coupled to the ground portion.

  Therefore, since the coupling portion of the chassis is connected to the ground circuit via the ground portion, the influence of electromagnetic noise can be reduced.

  In the invention described in claim 15, the distance between the opposing surface of the projecting portion of the second heat radiating plate and the circuit board is set to 1.2 mm or more.

  Therefore, the influence of electromagnetic noise can be further reduced.

  In the invention described in Claim 16, the resin sheet which has a heat radiating hole is attached to the surface on the opposite side to the surface which opposes the said circuit board in the base part of a said 2nd heat sink.

  Therefore, the finger does not come into contact with the second heat radiating plate at the time of heat radiation, and it is possible to improve safety such as prevention of burns while improving heat radiation.

  In the invention described in claim 17, an insertion hole is formed in the chassis, a base portion of the second heat radiation plate is attached to an outer surface of the chassis, and the second heat radiation plate is inserted into the insertion hole of the chassis. The protruding part is inserted and arranged.

  Accordingly, since the base portion of the second heat radiating plate is disposed on the outer surface side of the chassis, heat generated in the electronic component can be efficiently released to the outside, and heat dissipation can be further improved. .

  In the invention described in claim 18, a placement recess is formed in the chassis, the insertion hole is formed at a position penetrating a part of the placement recess, and the base of the second heat sink is formed in the placement recess. And a protruding portion of the second heat radiating plate is inserted into the insertion hole.

  Therefore, the second heat radiating plate does not protrude outward from the outer surface of the chassis, and the heat radiating structure can be downsized while improving the heat radiating property and the safety.

  In the invention described in claim 19, a resin sheet having a heat radiating hole is attached to a surface of the base portion of the second heat radiating plate opposite to the surface facing the circuit board, and the resin is disposed in the arrangement recess. A sheet is placed.

  Therefore, the resin sheet does not protrude outward from the outer surface of the chassis, and the heat dissipation structure can be downsized while ensuring good heat dissipation.

  In order to solve the above-described problem, another electronic device according to the present invention has an outer casing in which predetermined parts are arranged, and is arranged in the outer casing and connected to a component mounting unit and a ground circuit. A circuit board having a ground part and an electronic component mounted on one surface of the component mounting part as a heat source at the time of driving; and a flat plate shape disposed on the surface side of the circuit board on which the electronic component is mounted A first heat dissipating plate having a base portion and a projecting portion that protrudes from the base portion toward the circuit board and is opposed to one surface of the component mounting portion, and component mounting on the circuit board A first heat transfer body that is in close contact with the one surface of the part and the opposing surface of the protruding portion of the heat sink and that transfers heat generated in the electronic component to the heat sink.

  Accordingly, since the protruding portion of the first heat radiating plate is connected to the circuit board via the first heat transfer body and the base portion is located away from the circuit board, the heat radiating property of the heat generated in the electronic component can be reduced. Improvement and reduction of the influence by electromagnetic noise can be aimed at.

  Embodiments of the heat dissipation structure and electronic device of the present invention will be described below with reference to the accompanying drawings.

[Measurement A for heat dissipation performance]
First, the measurement A which shows the influence which the relationship between the area of a heat sink and the area of an electronic component exerts on heat dissipation performance in a heat dissipation structure will be described (see FIGS. 1 and 2).

  The heat dissipating structure and the electronic device according to the present invention improve heat dissipation by using a heat dissipating plate disposed on the other surface side of the circuit board, with respect to heat generated from the electronic component mounted on one surface of the circuit board. One purpose.

  Therefore, in measurement A, as shown in FIG. 1, the influence of the relationship between the area of the heat sink and the area of the electronic component on the heat dissipation performance was measured using the heat dissipation structure 50. For example, a chip component for performing image processing is used as the electronic component.

  In the heat dissipation structure 50, an electronic component 52 is mounted on one surface 51 a of the circuit board 51, a heat dissipation plate 53 is disposed on the other surface 51 b side of the circuit board 51, and heat transfer is performed between the heat dissipation plate 53 and the circuit board 51. A heat transfer sheet 54 that functions as a body is disposed. Both surfaces of the heat transfer sheet 54 are in close contact with the other surface 51 b of the circuit board 51 and one surface 53 a of the heat radiating plate 53.

  Measurement A is performed at room temperature of 27 ° C., the thickness of the circuit board 51 is 0.6 mm (sample a1) or 1.2 mm (samples a1 to a3), the size of the circuit board 51 is 130 mm × 130 mm, The thickness of the component 52 was 2.0 mm, the size of the electronic component 52 was 20 mm × 20 mm, and the heat generation amount of the electronic component 52 was 3 W. Also, aluminum is used as the heat sink 53, the thickness of the heat sink 53 is 0.5 mm (sample a2) or 1.0 mm (samples a1, a3, a4), and the size of the heat sink 53 is 10 mm × 10 mm to 100 mm. Changed to 10 mm intervals up to × 100 mm, the thickness of the heat transfer sheet 54 changed to 1.2 mm, and the size of the heat transfer sheet 54 changed from 10 mm × 10 mm to 100 mm × 100 mm at 10 mm intervals according to the size of the heat sink 53 did.

  About the result measured on said conditions, a chart and a graph are shown in FIG. FIG. 2 is a measurement result showing the average temperature of the electronic component 52 when the size of the heat sink 53 is changed. The average temperature is the average temperature on the surface of the electronic device (hereinafter the same).

  From the result of measurement A shown in FIG. 2, it can be seen that when the size of the heat dissipation plate 53 is 80 mm × 80 mm, the average temperature of the electronic component 52 hardly decreases in any of the samples a1 to a4. Therefore, it is considered that a value of 16 times or less obtained by dividing the area of the heat dissipation plate 53 (80 mm × 80 mm) by the area of the electronic component 52 (20 mm × 20 mm) is effective for ensuring good heat dissipation performance.

  Further, in order to ensure good heat dissipation performance, the average temperature of the electronic component 52 needs to be lowered by a certain level or more, and the area of the heat dissipation plate 53 is 30 mm × 30 mm or more where the average temperature has suddenly decreased. It can be seen that the area is good for securing the property. Therefore, it is considered that a value of about twice or more obtained by dividing the area of the heat dissipation plate 53 (30 mm × 30 mm) by the area of the electronic component 52 (20 mm × 20 mm) is effective to ensure good heat dissipation performance. .

  As described above, in order to ensure good heat dissipation performance, the area of the heat dissipation plate 53 is desirably 2 to 16 times the area of the electronic component 52.

[Measurement B regarding the influence of electromagnetic noise]
Below, measurement B which shows the influence of the electromagnetic noise regarding the distance of the generation source of an electromagnetic noise and a heat sink in a thermal radiation structure is demonstrated (refer FIG.3 and FIG.5).

  One object of the heat dissipation structure and the electronic apparatus of the present invention is to reduce the influence of electromagnetic noise.

  Therefore, in measurement B, as shown in FIGS. 3 and 4, the influence of electromagnetic noise on the distance between the electromagnetic noise source and the heat sink was measured using a heat dissipation structure 60. In the heat dissipation structure 60, a microstrip line 61 c is formed on one surface 61 a of the circuit board 61 as a source of electromagnetic noise, and a heat dissipation plate 63 is disposed on the one surface 61 a side of the circuit board 61.

  In measurement B, the size of the circuit board 61 is 100 mm × 100 mm, the size of the heat sink 63 is 60 mm × 60 mm, and the distance d between the circuit board 61 (microstrip line 61c) and the heat sink 63 (see FIG. 4). Was appropriately changed from 0.3 mm to 10 mm.

  About the result measured on said conditions, a graph is shown in FIG. In the graph of FIG. 5, the vertical axis indicates the maximum value of the far field intensity at a position of 3 m, and the horizontal axis indicates the distance d between the circuit board 61 (microstrip line 61c) and the heat sink 63.

  From the result of measurement B shown in FIG. 5, it can be seen that the maximum value of the far field strength becomes maximum when the distance d is about 1 mm, and the maximum value of the far field strength decreases as the distance d increases from about 1 mm. Further, the maximum value of the far field intensity when the distance d is smaller than 1.2 mm is larger than the maximum value of the far field strength when the distance d is 1.2 mm. Therefore, in order to reduce the influence of electromagnetic noise, it is desirable that the distance d between the electromagnetic noise source and the heat radiating plate 63 be 1.2 mm or more.

[Measurement C regarding heat dissipation performance and electromagnetic noise effects]
In the following, measurement C (measurement C1 and measurement C2) showing the influence of electromagnetic noise on the distance between the source of electromagnetic noise and the distance of the heat sink whose shape has been changed in the heat dissipation structure and the heat dissipation performance will be described (see FIGS. 6 to 14). ).

  The heat dissipation structure and the electronic device of the present invention are intended to improve the heat dissipation and reduce the influence of electromagnetic noise.

  Therefore, first, in measurement C1, the influence of the electromagnetic noise on the distance between the electromagnetic noise source and the heat sink was measured using the heat dissipation structure 60 (see FIGS. 6 and 7) and the heat dissipation structure 70 (see FIG. 8). .

  In the heat dissipation structure 60, a microstrip line (not shown) is formed on one surface 61 a of the circuit board 61 as a noise generation source (same as the microstrip line 61 c), and a flat plate shape is formed on the one surface 61 a side of the circuit board 61. A heat radiating plate 63 is arranged.

  In the heat dissipation structure 70, a microstrip line (same as the microstrip line 61c) is formed on one surface 61a of the circuit board 61 as a noise generation source, and a heat dissipation plate 73 is disposed on the one surface 61a side of the circuit board 61. Has been. The heat radiating plate 73 includes a flat base portion 73a and a protruding portion 73b protruding from the base portion 73a to the circuit board 61 side.

  In the measurement C1, the size of the circuit board 61 was 100 mm × 100 mm, and the sizes of the heat sinks 63 and 73 were 60 mm × 60 mm. In the heat dissipation structure 60, the distance d between the circuit board 61 (microstrip line) and the heat dissipation plate 63 is 2 mm (see FIG. 6) or 12 mm (see FIG. 7). ) And the base 73a of the heat sink 73 is 12 mm, and the distance da between the circuit board 61 (microstrip line) and the protrusion 73b of the heat sink 73 is 2 mm.

  The results of measuring the magnetic field strength distribution under the above conditions are shown in FIGS. 9 shows the measurement results when the distance d is 2 mm in the heat dissipation structure 60, FIG. 10 shows the measurement results when the distance d is 12 mm in the heat dissipation structure 60, and FIG. The measurement results when the distance d is 12 mm and the distance da is 2 mm are shown.

  9 to 11, level 7 to level 1 indicate the strength of the magnetic field strength, and level 7 indicates the range where the magnetic field strength is the strongest.

  In the heat dissipating structure 60 (see FIG. 6) when the distance d is 2 mm, as shown in FIG. 9, the heat dissipating plate 63 is adjacent to the electromagnetic wave of level 7 and is greatly affected by electromagnetic noise, and the distance d is 12 mm. In the heat dissipation structure 60 (see FIG. 7) in this case, as shown in FIG. 10, the heat dissipation plate 63 is not adjacent to the electromagnetic waves from the level 7 to the level 1 and is less affected by electromagnetic noise. Further, in the heat dissipation structure 70 (see FIG. 8) when the distance d is 12 mm and the distance da is 2 mm, a part of the base portion 73a of the heat dissipation plate 73 is level 1 electromagnetic waves as shown in FIG. Although the front end surface of the protrusion 73b of the heat radiating plate 73 is adjacent to the electromagnetic wave of level 5, the influence of electromagnetic noise is greatly reduced as compared with the heat radiating structure 60 shown in FIG.

  Next, in measurement C2, as shown in FIGS. 12 to 14, the heat dissipation performance was measured using the heat dissipation structure 60A, the heat dissipation structure 60B, and the heat dissipation structure 70A. The heat dissipation structure 60A, the heat dissipation structure 60B, and the heat dissipation structure 70A correspond to the heat dissipation structures 60, 60, and 70 shown in FIGS.

  As shown in FIGS. 12 and 13, the heat dissipating structures 60 </ b> A and 60 </ b> B have the electronic component 62 mounted on one surface 61 a of the circuit board 61 and the heat dissipating plate 63 disposed on the one surface 61 a side of the circuit board 61. Yes. A heat transfer sheet 64 is disposed between the electronic component 62 and the heat radiating plate 63, and both surfaces of the heat transfer sheet 64 are in close contact with the electronic component 62 and the heat radiating plate 63, respectively.

  As shown in FIG. 14, in the heat dissipation structure 70 </ b> A, the electronic component 62 is mounted on one surface 61 a of the circuit board 61, and the heat dissipation plate 73 is disposed on the one surface 61 a side of the circuit board 61. The heat radiating plate 73 includes a flat base portion 73a and a protruding portion 73b protruding from the base portion 73a to the circuit board 61 side. A heat transfer sheet 64 is disposed between the electronic component 62 and the protrusion 73 b of the heat sink 73, and both surfaces of the heat transfer sheet 64 are in close contact with the electronic component 62 and the protrusion 73 b of the heat sink 73, respectively.

  In the measurement C2, the size of the circuit board 61 was 100 mm × 100 mm, and the sizes of the heat sinks 63 and 73 were 60 mm × 60 mm. In the heat dissipation structure 60A, the distance d between the circuit board 61 and the heat dissipation plate 63 is 2 mm, in the heat dissipation structure 60B, the distance d between the circuit board 61 and the heat dissipation plate 63 is 12 mm, and in the heat dissipation structure 70, the circuit board 61 and the heat dissipation plate 73 are provided. The distance d between the circuit board 61 and the protrusion 73b of the heat radiating plate 73 was set to 2 mm.

  In the heat dissipation structures 60A, 60B, and 70A, the average temperature of the electronic component 62 when the electronic component 62 was driven was measured.

  The average temperature of the electronic component 62 in the heat dissipation structure 60A is 51.39 ° C., the average temperature of the electronic component 62 in the heat dissipation structure 60B is 51.30 ° C., and the average temperature of the electronic component 62 in the heat dissipation structure 70A is 49. .85 ° C. Therefore, it can be seen that the heat dissipation structure 70A has higher heat dissipation performance than the heat dissipation structures 60A and 60B.

  As shown in the above measurement C1 and measurement C2, the heat dissipation structure 70 (70A) provided with the heat dissipation plate 73 having the protrusion 73b has a high heat dissipation performance and has a low electromagnetic noise effect. It was.

[Measurement D for heat dissipation performance due to structural differences]
Below, the measurement D which shows the thermal radiation performance by the difference in a structure in a thermal radiation structure is demonstrated.

  The heat dissipating structure and the electronic device according to the present invention improve heat dissipation by using a heat dissipating plate disposed on the other surface side of the circuit board, with respect to heat generated from the electronic component mounted on one surface of the circuit board. One purpose.

  Therefore, in measurement D, the heat dissipation performance was measured for each different structure (heat dissipation structure). The heat dissipation structure used for the measurement D is the heat dissipation structure 80A, the heat dissipation structure 80B, the heat dissipation structure 80C, the heat dissipation structure 80D, and the heat dissipation structure 80E.

  As shown in FIG. 15, the heat dissipation structure 80 </ b> A includes a circuit board 81, and an electronic component 82 is mounted on one surface 81 a of the circuit board 81.

  On the other surface 81b side of the circuit board 81, a chassis 83 formed of a resin material constituting a part of the outer casing is disposed. The chassis 83 is formed with a shallow placement recess 83a that opens downward, and an insertion hole 83b that is vertically penetrated is formed at the center of the placement recess 83a.

  A resin sheet 84 is arranged in the arrangement recess 83 a of the chassis 83. The resin sheet 84 is formed with a plurality of heat radiation holes 84a, 84a,.

  As shown in FIG. 16, the heat dissipation structure 80 </ b> B includes a circuit board 81 and a heat sink 85, and an electronic component 82 is mounted on one surface 81 a of the circuit board 81.

  On the other surface 81b side of the circuit board 81, a chassis 83 formed of a resin material constituting a part of the outer casing is disposed. The chassis 83 is formed with a shallow placement recess 83a that opens downward, and an insertion hole 83b that is vertically penetrated is formed at the center of the placement recess 83a.

  A resin sheet 84 is arranged in the arrangement recess 83 a of the chassis 83. The resin sheet 84 is formed with a plurality of heat radiation holes 84a, 84a,.

  The heat sink 85 is disposed on one surface 81a side of the circuit board 81, and includes a flat plate-like base portion 85a facing upward and downward, and heat radiation fins 85b, 85b,... Protruding upward from the base portion 85a.

  A heat transfer sheet 86 is disposed between the electronic component 82 and the heat sink 85, and both surfaces of the heat transfer sheet 86 are in close contact with the electronic component 82 and the base 85a of the heat sink 85, respectively.

  As shown in FIG. 17, the heat dissipation structure 80 </ b> C includes a circuit board 81, a heat sink 85, and a heat spreader 87, and an electronic component 82 is mounted on one surface 81 a of the circuit board 81.

  On the other surface 81b side of the circuit board 81, a chassis 83 formed of a resin material constituting a part of the outer casing is disposed. The chassis 83 is formed with a shallow placement recess 83a that opens downward, and an insertion hole 83b that is vertically penetrated is formed at the center of the placement recess 83a.

  A resin sheet 84 is arranged in the arrangement recess 83 a of the chassis 83. The resin sheet 84 is formed with a plurality of heat radiation holes 84a, 84a,.

  The heat sink 85 is disposed on one surface 81a side of the circuit board 81, and includes a flat plate-like base portion 85a facing upward and downward, and heat radiation fins 85b, 85b,... Protruding upward from the base portion 85a.

  The heat spreader 87 has a flat heat radiation surface portion 87a facing upward and downward, and a mounted projection 87b protruding sideways from the heat radiation surface portion 87a. The mounted projection 87b is attached to the circuit board 81 with a mounting screw 100. It has been. The heat dissipating surface portion 87 a of the heat spreader 87 is in close contact with the base portion 85 a of the heat sink 85.

  A heat transfer sheet 86 is disposed between the electronic component 82 and the heat spreader 87, and both surfaces of the heat transfer sheet 86 are in close contact with the electronic component 82 and the heat radiation surface portion 87a of the heat spreader 87, respectively.

  As shown in FIG. 18, the heat dissipation structure 80 </ b> D includes a circuit board 81, a heat sink 85, a heat spreader 87, and a heat dissipation plate 88, and an electronic component 82 is mounted on one surface 81 a of the circuit board 81.

  On the other surface 81b side of the circuit board 81, a chassis 83D formed of a resin material constituting a part of the outer casing is disposed. The chassis 83D is formed with a shallow placement recess 83a that opens downward, and an insertion hole 83b that is vertically penetrated is formed at the center of the placement recess 83a. The chassis 83D is provided with a coupling portion 83c.

  The heat radiating plate 88 includes a flat base portion 88a facing upward and downward, and a protruding portion 88b protruding upward from the central portion of the base portion 88a. The base portion 88a is disposed in the disposing recess 83a of the chassis 83D. 88b is inserted through the insertion hole 83b of the chassis 83D and disposed inside the outer casing.

  A heat transfer sheet 89 is disposed between the portion of the circuit board 81 where the electronic component 82 is mounted and the protrusion 88b of the heat sink 88, and both surfaces of the heat transfer sheet 89 protrude from the circuit board 81 and the heat sink 88, respectively. It is in close contact with the portion 88b.

  A resin sheet 84 is arranged in the arrangement recess 83a of the chassis 83D. The resin sheet 84 is disposed in close contact with the lower surface of the base portion 88 a of the heat sink 88. The resin sheet 84 is formed with a plurality of heat radiation holes 84a, 84a,.

  The heat sink 85 is disposed on one surface 81a side of the circuit board 81, and includes a flat plate-like base portion 85a facing upward and downward, and heat radiation fins 85b, 85b,... Protruding upward from the base portion 85a.

  The heat spreader 87 includes a flat plate-shaped heat radiation surface portion 87a facing in the vertical direction and a mounting projection portion 87b projecting sideways from the heat radiation surface portion 87a. The heat dissipating surface portion 87 a of the heat spreader 87 is in close contact with the base portion 85 a of the heat sink 85.

  A mounting projection 87b of the heat spreader 87 and a coupling portion 83c of the chassis 83D are attached to the circuit board 81 with mounting screws 100 with the circuit board 81 sandwiched from above and below.

  A heat transfer sheet 86 is disposed between the electronic component 82 and the heat spreader 87, and both surfaces of the heat transfer sheet 86 are in close contact with the electronic component 82 and the heat radiation surface portion 87a of the heat spreader 87, respectively.

  As shown in FIG. 19, the heat dissipation structure 80 </ b> E includes a circuit board 81, a heat sink 85, a heat spreader 87, and a heat dissipation plate 88, and an electronic component 82 is mounted on one surface 81 a of the circuit board 81.

  On the other surface 81b side of the circuit board 81, a chassis 83E formed of a metal material (iron material) constituting a part of the outer casing is disposed. The chassis 83E is formed with a shallow placement recess 83a that is opened downward, and an insertion hole 83b that is vertically penetrated is formed at the center of the placement recess 83a.

  The heat dissipation structure 80E has the same structure as the heat dissipation structure 80D (see FIG. 18) except that a chassis 83E formed of an iron material is provided instead of the chassis 83D formed of a resin material. Therefore, the description of the heat dissipation structure 80E other than the chassis 83E is omitted.

  The measurement D was performed at a room temperature of 45 ° C., and the average temperature of the electronic component 82 when the electronic component 82 was driven was measured in the heat dissipation structures 80A, 80B, 80C, 80D, and 80E. FIG. 20 is a graph showing the measurement results.

  The average temperature of the electronic component 82 in the heat dissipation structure 80A is 105 ° C, the average temperature of the electronic component 82 in the heat dissipation structure 80B is 93 ° C, and the average temperature of the electronic component 82 in the heat dissipation structure 80C is 86 ° C. The average temperature of the electronic component 82 in the heat dissipation structure 80D was 82 ° C., and the average temperature of the electronic component 82 in the heat dissipation structure 80E was 79 ° C. The temperature H at which the electronic component 82 used for measurement may break down due to heat is 90 ° C. Considering this temperature H, the heat dissipation structures 80C, 80D, and 80E are desirable structures when considering the heat dissipation performance. In view of temperature variation, it is more desirable to use the heat dissipation structure 80D or the heat dissipation structure 80E.

  In measurement D, when the heat dissipation structure 80A and the heat dissipation structure 80B are compared, it can be seen that the heat dissipation structure 80B has an average temperature drop of 12 ° C. relative to the heat dissipation structure 80A, and the effect of heat dissipation performance by the heat sink 85 is produced. . Comparing the heat dissipation structure 80B and the heat dissipation structure 80C, it can be seen that the average temperature of the heat dissipation structure 80C is 4 ° C lower than that of the heat dissipation structure 80B, and the effect of the heat dissipation performance by the heat spreader 87 occurs. Comparing the heat dissipation structure 80C and the heat dissipation structure 80D, it can be seen that the average temperature of the heat dissipation structure 80D is 7 ° C lower than that of the heat dissipation structure 80C, and the effect of the heat dissipation performance by the heat dissipation plate 88 is produced. Comparing the heat dissipation structure 80D and the heat dissipation structure 80E, the heat dissipation structure 80E has an average temperature that is 3 ° C lower than that of the heat dissipation structure 80D, and the effect of the heat dissipation performance is produced by the chassis 83E formed of a metal material. I understand.

[Specific configuration of electronic equipment and heat dissipation structure]
Next, specific embodiments of the heat dissipation structure of the present invention and an electronic apparatus provided with the heat dissipation structure will be described.

  In the following first and second embodiments, the electronic apparatus of the present invention is applied to a disk recording / reproducing apparatus, and the heat radiating structure of the present invention is applied to a heat radiating structure provided in the disk recording / reproducing apparatus. It is a thing.

  The applicable range of the electronic apparatus and the heat dissipation structure of the present invention is not limited to the disk recording / reproducing apparatus and the heat dissipation structure provided in the disk recording / reproducing apparatus. The electronic apparatus of the present invention is a recording / reproducing apparatus using a recording medium other than a disk recording / reproducing apparatus, an audio recording / reproducing apparatus, an imaging apparatus, a network communication apparatus, an information processing apparatus such as a personal computer or a PDA (Personal Digital Assistant), etc. It can be widely applied to various electronic devices. Further, the heat dissipation structure of the present invention can be widely applied to the heat dissipation structure provided in these various electronic devices.

<First Embodiment>
First, a first embodiment will be described (see FIGS. 21 to 27).

  The electronic device (disc recording / reproducing apparatus) 1 is configured by arranging required parts inside an outer casing 2, and the outer casing 2 is configured by combining a case body 3, a chassis 4, a front panel 5, and a rear panel 6. (See FIGS. 21 to 23). The outer casing 2 is formed in, for example, a flat, horizontally long, substantially rectangular parallelepiped shape.

  The case body 3 includes a top surface portion 3a facing in the vertical direction and side surface portions 3b and 3b projecting downward from left and right side portions of the top surface portion 3a.

  The chassis 4 is made of a metal material or a resin material, and includes a substantially flat bottom plate portion 7 facing upward and downward, and side plate portions 8 and 8 protruding upward from the left and right side portions of the bottom plate portion 7 respectively. The bottom plate portion 7 of the chassis 4 is formed with a shallow arrangement recess 7a that opens downward (see FIGS. 23 and 24), and an insertion hole 7b that is vertically penetrated is formed in the center of the arrangement recess 7a. . The bottom plate portion 7 of the chassis 4 is provided with a coupling portion 7c on the side of the placement recess 7a.

  The case body 3 is coupled to the chassis 4 such that the side surface portions 3b and 3b cover the side plate portions 8 and 8 from the outside.

  The front panel 5 is attached to the front end portion of the case body 3 and the front end portion of the chassis 4, and has a disk insertion / removal hole opened in the front-rear direction. The disc insertion / removal hole is opened and closed by the shutter 9. A plurality of operation buttons 10, 10,... Are arranged on the front panel 5. As the operation buttons 10, 10,..., For example, a power button, a disc playback button, a disc recording button, a function button for executing various functions, and the like are provided.

  A disk drive unit 11 is disposed inside the outer casing 2 behind the disk insertion / removal hole. A disc-shaped recording medium (not shown) inserted through a disc insertion / removal hole formed in the front panel 5 is mounted on the disc drive unit 11, and information signals are recorded on or reproduced from the disc-shaped recording medium. The disc-shaped recording medium on which the information signal is recorded or reproduced is ejected from the disc insertion / removal hole and taken out to the outside.

  A heat dissipation structure 12 is provided on the side of the disk drive unit 11 (see FIGS. 22 and 24). The heat dissipation structure 12 includes a circuit board 13, a heat sink 14, a heat spreader 15, and a heat dissipation plate 16 (see FIG. 24).

  The circuit board 13 is oriented in the vertical direction, and a substantially central portion is provided as a component mounting portion 17. An electronic component 18 is mounted on the component mounting portion 17 on one surface (upper surface) 13 a of the circuit board 13. The electronic component 18 is a chip component for performing image processing, for example, and is connected to a predetermined wiring pattern (not shown) formed on the circuit board 13. The electronic component 18 is a heat source that generates heat during driving, and the electronic component 18 and the wiring pattern are sources of electromagnetic noise.

  The heat sink 14 is arranged on one surface 13a side of the circuit board 13, and includes a flat plate-like base portion 14a facing in the vertical direction and heat radiation fins 14b, 14b,... Protruding upward from the base portion 14a.

  As shown in FIG. 25, the heat spreader 15 includes a flat plate-shaped heat radiation surface portion 19 that faces in the up-down direction, mounted projections 20, 20, 20 that protrude substantially horizontally from the heat radiation surface portion 19, and both front and rear sides of the heat radiation surface portion 19. .., Projecting downward from the edges, respectively, and projecting protrusions 22, 22,... Projecting upward from the front and rear side edges of the heat dissipating surface 19 respectively. The heat radiating surface portion 19 is formed to have substantially the same size as the base portion 14 a of the heat sink 14. Screw insertion holes 20a, 20a, and 20a penetrating vertically are formed at the tip ends of the attached projections 20, 20, and 20, respectively.

  The base 14a of the heat sink 14 is disposed on the heat dissipating surface 19 of the heat spreader 15, and the coupling protrusions 22, 22,... (See FIG. 26). In a state where the heat sink 14 is coupled to the heat spreader 15, the heat radiating surface portion 19 of the heat spreader 15 and the base portion 14 a of the heat sink 14 are in close contact with each other.

  A first heat transfer sheet 23 functioning as a first heat conductor is disposed between the electronic component 18 and the heat spreader 15, and both surfaces of the first heat transfer sheet 23 are the upper surface of the electronic component 18 and the heat spreader, respectively. 15 is closely attached to the lower surface of the heat radiating surface portion 19.

  The heat spreader 15 is connected to ground portions 13c, 13c,... Formed on the circuit board 13 by soldering, for example, by connecting protrusions 21, 21,. The ground portions 13c, 13c,... Are connected to a ground circuit (not shown), and the connection protrusions 21, 21,... Are connected to the ground portions 13c, 13c,. Earth).

  In the heat spreader 15, mounting screws 30, 30, 30 are respectively inserted through screw insertion holes 20 a, 20 a, 20 a into ground portions 13 d, 13 d, 13 d in which mounted protrusions 20, 20, 20 are formed on the circuit board 13. Attached. The ground portions 13d, 13d, and 13d are connected to the ground circuit in the same manner as the ground portions 13c, 13c,..., And the mounted protrusions 20, 20, and 20 are connected to the ground portions 13d, 13d, and 13d, respectively. In this way, grounding (earthing) is also achieved. Therefore, the connecting projections 21, 21,... Of the heat spreader 15 are connected to the ground portions 13c, 13c,..., Respectively, and the attached protruding portions 20, 20, 20 are respectively connected to the ground portions 13d, 13d, 13d. By being attached, the influence of electromagnetic noise is greatly reduced.

  The heat radiating plate 16 is made of a metal material such as aluminum or iron, and includes a flat plate-like base portion 16a facing in the vertical direction and a protruding portion 16b protruding upward from the central portion of the base portion 16a (see FIG. 24). The protruding portion 16b is formed by, for example, drawing, and the upper surface of the protruding portion 16b is formed as a facing surface 16c. The heat radiating plate 16 has a base portion 16 a arranged in the arrangement recess 7 a of the chassis 4, and a protruding portion 16 b inserted through the insertion hole 7 b of the chassis 4 and arranged inside the outer casing 2. The heat radiating plate 16 is fixed to the chassis 4 by appropriate means such as adhesion, screwing, and engagement, for example, in a state where the base portion 16a is arranged in the arrangement recess 7a.

  A second heat transfer sheet 24 that functions as a second heat transfer body is disposed between the component mounting portion 17 of the circuit board 13 and the protrusion 16 b of the heat sink 16, and both surfaces of the second heat transfer sheet 24 are arranged. Are in close contact with the component mounting portion 17 on the other surface 13b of the circuit board 13 and the opposing surface 16c of the protruding portion 16b of the heat sink 16.

  A resin sheet 25 is inserted into the arrangement recess 7 a of the chassis 4 from below the heat radiating plate 16. In a state where the resin sheet 25 is in close contact with the lower surface of the base portion 16a of the heat radiating plate 16, the resin sheet 25 is fixed by, for example, adhesion. In the resin sheet 25, a plurality of heat radiation holes 25a, 25a,.

  As described above, the heat spreader 15 is attached to the ground portion 13d formed on the circuit board 13 by the mounting screw 30 with the mounting projection 20 attached thereto, and at the same time, the coupling portion provided on the bottom plate portion 7 of the chassis 4 7 c is attached to the circuit board 13 by the attaching screw 30. Accordingly, the attached protrusion 20 and the coupling portion 7c are attached to the ground portion 13d by the attachment screw 30 with the circuit board 13 sandwiched from above and below.

  In the electronic device 1 configured as described above, the electronic component 18 generates heat when the electronic component 18 is driven. Heat generated in the electronic component 18 is transmitted to the heat spreader 15 via the first heat transfer sheet 23, transmitted from the heat spreader 15 to the heat sink 14, and released from the heat sink 14.

  Further, the heat generated in the electronic component 18 is also transmitted to the heat radiating plate 16 through the circuit board 13 and the second heat transfer sheet 24, and from the heat radiating plate 16 to the heat radiating holes 25a, 25a,. It is discharged to the outside through. At this time, when the chassis 4 is formed of a material having high thermal conductivity such as a metal material, the heat generated in the electronic component 18 is transmitted from the heat radiating plate 16 to the chassis 4 and is also released from the chassis 4. .

  On the other hand, in the electronic device 1, when the electronic component 18 is driven, the electronic component 18 generates heat and electromagnetic noise is generated from the electronic component 18 and the wiring pattern. At this time, the attached projections 20, 20, 20 and the connection projections 21, 21,... Of the heat spreader 15 are connected to the ground circuit through the ground portions 13d, 13d, 13d, 13c, 13c,. Therefore, the influence of electromagnetic noise is reduced.

  Further, since the coupling portion 7c of the chassis 4 is attached to the ground portion 13d of the circuit board 13 together with the attached projection 20, the further reduction due to electromagnetic noise can be achieved.

  Further, the heat radiating plate 16 includes a base portion 16 a and a protruding portion 16 b protruding from the base portion 16 a toward the circuit board 13, and only the protruding portion 16 b is connected to the circuit board 13 via the second heat transfer sheet 24. Since the base portion 16a is positioned away from the circuit board 13, the influence of electromagnetic noise is reduced as shown in the measurement C1 (see FIG. 11).

<Modification in the first embodiment>
Below, heat dissipation structure 12A which concerns on the modification in 1st Embodiment is demonstrated (refer FIG. 27).

  The heat radiating structure 12 </ b> A includes a circuit board 13, a heat sink 14, and a heat radiating plate 16.

  The circuit board 13 is oriented in the vertical direction, and a substantially central portion is provided as a component mounting portion 17. An electronic component 18 is mounted on the component mounting portion 17 on one surface (upper surface) 13 a of the circuit board 13. The electronic component 18 is connected to a predetermined wiring pattern (not shown) formed on the circuit board 13. The electronic component 18 is a heat source that generates heat during driving, and the electronic component 18 and the wiring pattern are sources of electromagnetic noise.

  The heat sink 14 is arranged on one surface 13a side of the circuit board 13, and includes a flat plate-like base portion 14a facing in the vertical direction and heat radiation fins 14b, 14b,... Protruding upward from the base portion 14a.

  A first heat transfer sheet 23 is disposed between the electronic component 18 and the heat sink 14, and both surfaces of the first heat transfer sheet 23 are in close contact with the upper surface of the electronic component 18 and the lower surface of the base portion 14 a of the heat sink 14. Yes.

  The heat radiating plate 16 is made of a metal material such as aluminum or iron, and includes a flat plate-like base portion 16a facing upward and downward and a protruding portion 16b protruding upward from the center portion of the base portion 16a. The protruding portion 16b is formed by, for example, drawing, and the upper surface of the protruding portion 16b is formed as a facing surface 16c. The base 16a of the heat sink 16 is disposed on the upper surface of the bottom plate 7A of the chassis 4A. The chassis 4A has a bottom plate portion 7A formed in a flat plate shape. Unlike the chassis 4, the chassis 4A is not formed with the arrangement recess 7a and the insertion hole 7b. The base 16a of the heat radiating plate 16 is fixed to the chassis 4A by appropriate means such as adhesion, screwing, and engagement.

  A second heat transfer sheet 24 is disposed between the component mounting portion 17 of the circuit board 13 and the protruding portion 16b of the heat radiating plate 16, and both surfaces of the second heat transfer sheet 24 are on the other side of the circuit board 13. The component mounting part 17 in 13b and the opposed surface 16c of the protruding part 16b in the heat sink 16 are in close contact with each other.

  Also in the heat dissipation structure 12 </ b> A described above, the heat generated in the electronic component 18 is released from the heat sink 14 and the heat dissipation plate 16, similarly to the heat dissipation structure 12. Further, the heat radiating plate 16 includes a base portion 16 a and a protruding portion 16 b protruding from the base portion 16 a toward the circuit board 13, and only the protruding portion 16 b is connected to the circuit board 13 via the second heat transfer sheet 24. Since the base portion 16a is positioned away from the circuit board 13, the influence of electromagnetic noise is reduced.

  Note that, similarly to the heat dissipation structure 12, the heat dissipation structure 12 </ b> A may be configured to dispose the heat spreader 15.

[Summary 1]
As described above, in the electronic device 1, the heat radiating plate 16 includes the base portion 16 a and the protruding portion 16 b protruding from the base portion 16 a toward the circuit board 13, and the protruding portion 16 b is the second heat transfer. The base portion 16 a is connected to the circuit board 13 via the sheet 24 and is positioned away from the circuit board 13.

  Therefore, it is possible to improve the heat dissipation of heat generated in the electronic component 18 and reduce the influence of electromagnetic noise.

  In particular, when a large-area metal plate is positioned in the vicinity of the electromagnetic noise generation source, the influence is great. However, the large base portion 16a of the heat radiating plate 16 is positioned away from the electromagnetic noise generation source. The influence of electromagnetic noise can be effectively reduced.

  Moreover, since high heat dissipation performance is ensured by making the protrusion part 16b of the heat sink 16 contact the circuit board 13 via the 2nd heat transfer sheet 24, it is necessary to arrange | position the fan motor for improving heat dissipation. Nor. Accordingly, it is possible to reduce the size of the electronic component 18 by reducing noise, manufacturing cost, and the number of components.

  Furthermore, by disposing the base portion 16a of the heat radiating plate 16 on the outer surface side of the chassis 4, the heat generated in the electronic component 18 can be efficiently released to the outside of the electronic device 1 and the heat dissipation is further improved. Can be achieved.

  Furthermore, by setting the distance between the facing surface 16c of the protrusion 16b of the heat sink 16 and the circuit board 13 to be 1.2 mm or more, the influence of electromagnetic noise can be further reduced from the result of the measurement B (see FIG. 5). Can do.

  Further, by attaching a resin sheet 25 having heat radiation holes 25a, 25a,... On the surface opposite to the circuit board 13 in the base portion 16a of the heat radiation plate 16, a finger is placed on the heat radiation plate 16 during heat radiation. It is possible to improve safety such as prevention of burns after improving heat dissipation without contact.

  Further, by forming the placement recess 7a and the insertion hole 7b in the chassis 4, the base portion 16a of the heat sink 16 is placed in the placement recess 7a, and the protrusion 16b of the heat sink 16 is inserted and placed in the insertion hole 7b. The heat radiating plate 16 does not protrude downward from the lower surface of the chassis 4, and the heat radiating structure 12 can be downsized while ensuring good heat radiating properties.

  In addition, by arranging the resin sheet 25 in the arrangement recess 7 a of the chassis 4, it is possible to reduce the size of the heat dissipation structure 12 while improving heat dissipation and safety.

  In addition, although the example using the heat transfer sheet as the heat transfer body has been described above, the heat transfer body is not limited to the heat transfer sheet, and the heat transfer body may be, for example, a heat transfer grease. It is also possible to use another heat transfer body having a high transfer rate.

<Second Embodiment>
Next, a second embodiment will be described (see FIGS. 28 to 30).

  Note that the heat dissipation structure according to the second embodiment described below is mainly dissipated on the surface side on which the electronic components of the circuit board are mounted, as compared with the heat dissipation structure according to the first embodiment described above. The difference is that a plate (first heat radiating plate) is arranged. Therefore, in the second embodiment, only the portions that are different from the heat dissipation structure according to the first embodiment will be described in detail, and the other portions will be described in detail according to the first embodiment. The same reference numerals as those used for the same parts in FIG.

  The heat dissipation structure 12B according to the second embodiment includes a circuit board 13 and a first heat dissipation plate 16B (see FIG. 24). Unlike the heat dissipation structure according to the first embodiment, the heat dissipation structure 12B is not provided with a heat sink and a heat spreader.

  A first heat radiating plate 16 </ b> B is disposed on one surface 13 a side of the circuit board 13.

  The first heat radiating plate 16B is made of a metal material such as aluminum or iron, and has a flat plate-like base portion 16d facing upward and downward, a protruding portion 16e protruding downward from the base portion 16d, and a lateral side of the base portion 16d. It has the connection part 16f protruded below from the one end part, and the to-be-attached protrusion part 16g protruded to the side from the lower end part of the connection part 16f.

  The protruding portion 16e is formed by, for example, drawing, and the lower surface of the protruding portion 16e is formed as a facing surface 16h.

  The first heat radiating plate 16 </ b> B is attached to a ground portion 13 d formed with a projection 16 g to be attached to the circuit board 13 with an attachment screw 30. By attaching the attached protrusion 16g of the first heat radiating plate 16B to the ground portion 13d, the influence of electromagnetic noise is greatly reduced.

  A first heat transfer sheet 26 functioning as a first heat transfer body is disposed between the electronic component 18 and the protruding portion 16e of the first heat radiating plate 16B, and both surfaces of the first heat transfer sheet 26 are respectively The electronic component 18 is in close contact with the upper surface of the electronic component 18 and the opposing surface 16h of the first heat radiating plate 16B.

  A chassis 4A is disposed on the other surface 13b side of the circuit board 13, and the chassis 4A has a bottom plate portion 7A formed in a flat plate shape.

  In the heat dissipation structure 12B configured as described above, the electronic component 18 generates heat when the electronic component 18 is driven. The heat generated in the electronic component 18 is transmitted to the first heat radiating plate 16B via the first heat transfer sheet 26 and is released from the first heat radiating plate 16B.

  On the other hand, when the electronic component 18 is driven, the electronic component 18 generates heat and electromagnetic noise is generated from the electronic component 18 and the wiring pattern. At this time, since the first heat radiating plate 16B is connected to the ground circuit via the ground portion 13d, the influence of electromagnetic noise is reduced.

  The first heat radiating plate 16B has a base portion 16d and a protruding portion 16e protruding from the base portion 16d to the circuit board 13 side, and the protruding portion 16e is interposed between the circuit board 13 and the first heat transfer sheet 26. Since the base portion 16d is positioned apart from the circuit board 13 as shown in FIG. 11, the influence of electromagnetic noise is reduced as shown in the measurement C1 (see FIG. 11).

  In the heat dissipation structure 12B, it is desirable that the distance between the facing surface 16h of the protrusion 16e of the first heat dissipation plate 16B and the circuit board 13 is 1.2 mm or more.

<Modification in Second Embodiment>
Below, heat dissipation structure 12C, 12D which concerns on the modification in 2nd Embodiment is demonstrated.

  First, a heat dissipation structure 12C according to a first modification of the second embodiment will be described (see FIG. 29).

  A heat dissipation structure 12C according to the first modification includes a circuit board 13, a first heat dissipation plate 16B, and a second heat dissipation plate 16C. Unlike the heat dissipation structure according to the first embodiment, the heat dissipation structure 12C is not provided with a heat sink and a heat spreader.

  A first heat radiating plate 16 </ b> B is disposed on one surface 13 a side of the circuit board 13.

  A first heat transfer sheet 26 is disposed between the electronic component 18 and the protruding portion 16e of the first heat radiating plate 16B, and both surfaces of the first heat transfer sheet 26 are the upper surface of the electronic component 18 and the first heat transfer sheet 26, respectively. The heat sink 16B is in close contact with the facing surface 16h.

  A second heat radiating plate 16 </ b> C is disposed on the other surface 13 b side of the circuit board 13.

  The second heat radiating plate 16C is made of a metal material such as aluminum or iron, and includes a flat plate-like base portion 16i facing in the vertical direction and a protruding portion 16j protruding upward from the central portion of the base portion 16i. The protruding portion 16j is formed by, for example, drawing, and the upper surface of the protruding portion 16j is formed as a facing surface 16k. The second heat radiating plate 16 </ b> C has a base portion 16 i disposed in the disposition recess 7 a of the chassis 4, and a protruding portion 16 j disposed through the insertion hole 7 b of the chassis 4 and disposed inside the outer casing 2. The second heat radiating plate 16C is fixed to the chassis 4 by appropriate means such as adhesion, screwing, and engagement in a state where the base portion 16i is arranged in the arrangement recess 7a.

  A second heat transfer sheet 27 functioning as a second heat transfer body is disposed between the component mounting portion 17 of the circuit board 13 and the protruding portion 16j of the second heat radiating plate 16C, and the second heat transfer sheet. 27 are in close contact with the component mounting portion 17 on the other surface 13b of the circuit board 13 and the opposing surface 16k of the protruding portion 16j of the second heat radiating plate 16C.

  A resin sheet 25 is inserted into the arrangement recess 7a of the chassis 4 from below the second heat radiating plate 16C. The resin sheet 25 is fixed by, for example, adhesion or the like in a state where the resin sheet 25 is in close contact with the lower surface of the base portion 16i of the second heat radiating plate 16C.

  As described above, the first heat radiating plate 16B is attached to the ground portion 13d formed on the circuit board 13 with the attachment protrusion 16g by the attachment screw 30. At the same time, the first heat radiating plate 16B is provided on the bottom plate portion 7 of the chassis 4. The coupled portion 7c is attached to the circuit board 13 by the attaching screw 30. Accordingly, the attached protrusion 16g and the coupling portion 7c are attached to the ground portion 13d by the attachment screw 30 with the circuit board 13 sandwiched from above and below.

  In the heat dissipation structure 12C configured as described above, the electronic component 18 generates heat when the electronic component 18 is driven. The heat generated in the electronic component 18 is transmitted to the first heat radiating plate 16B via the first heat transfer sheet 26 and is released from the first heat radiating plate 16B.

  Further, the heat generated in the electronic component 18 is also transmitted to the second heat radiating plate 16C via the circuit board 13 and the second heat transfer sheet 27, and the heat radiating holes 25a of the resin sheet 25 from the second heat radiating plate 16C, It is discharged to the outside through 25a,. At this time, when the chassis 4 is formed of a material having high thermal conductivity such as a metal material, the heat generated in the electronic component 18 is transmitted from the second heat radiating plate 16C to the chassis 4, and the chassis 4 also Released.

  On the other hand, when the electronic component 18 is driven, the electronic component 18 generates heat and electromagnetic noise is generated from the electronic component 18 and the wiring pattern. At this time, since the first heat radiating plate 16B is connected to the ground circuit via the ground portion 13d, the influence of electromagnetic noise is reduced.

  Further, since the coupling portion 7c of the chassis 4 is attached to the ground portion 13d of the circuit board 13 together with the attached projection 16g, further reduction due to electromagnetic noise can be achieved.

  Further, the second heat radiating plate 16C includes a base portion 16i and a protruding portion 16j protruding from the base portion 16i to the circuit board 13 side, and only the protruding portion 16j is interposed between the circuit board 13 and the second heat transfer sheet 27. Since the base portion 16i is located at a distance from the circuit board 13, the influence of electromagnetic noise is reduced as shown in the measurement C1 (see FIG. 11).

  In the heat radiating structure 12C, it is desirable that the distance between the facing surface 16h of the protruding portion 16e of the first heat radiating plate 16B and the circuit board 13 is 1.2 mm or more, and in the protruding portion 16j of the second heat radiating plate 16C. It is desirable that the distance between the facing surface 16k and the circuit board 13 is 1.2 mm or more.

  Next, a heat dissipation structure 12D according to a second modification example of the second embodiment will be described (see FIG. 30).

  A heat dissipation structure 12D according to the second modification includes a circuit board 13, a first heat dissipation plate 16B, and a second heat dissipation plate 16C. Unlike the heat dissipation structure according to the first embodiment, the heat dissipation structure 12D is not provided with a heat sink and a heat spreader.

  A first heat radiating plate 16 </ b> B is disposed on one surface 13 a side of the circuit board 13.

  A first heat transfer sheet 26 is disposed between the electronic component 18 and the projecting portion 16e of the first heat radiating plate 16B. The heat sink 16B is in close contact with the facing surface 16h.

  A second heat radiating plate 16 </ b> C is disposed on the other surface 13 b side of the circuit board 13.

  The second heat radiating plate 16C is made of a metal material such as aluminum or iron, and includes a flat plate-like base portion 16i facing in the vertical direction and a protruding portion 16j protruding upward from the central portion of the base portion 16i. The protruding portion 16j is formed by, for example, drawing, and the upper surface of the protruding portion 16j is formed as a facing surface 16k.

  The base 16i of the second heat radiating plate 16C is disposed on the upper surface of the bottom plate 7A of the chassis 4A. The base portion 16i of the second heat radiating plate 16C is fixed to the chassis 4A by appropriate means such as adhesion, screwing, and engagement.

  A second heat transfer sheet 27 functioning as a second heat transfer body is disposed between the component mounting portion 17 of the circuit board 13 and the protruding portion 16j of the second heat radiating plate 16C, and the second heat transfer sheet. 27 are in close contact with the component mounting portion 17 on the other surface 13b of the circuit board 13 and the opposing surface 16k of the protruding portion 16j of the second heat radiating plate 16C.

  As described above, the first heat radiating plate 16 </ b> B is attached to the ground portion 13 d where the attached protrusion 16 g is formed on the circuit board 13 by the attachment screw 30. By attaching the attached protrusion 16g of the first heat radiating plate 16B to the ground portion 13d, the influence of electromagnetic noise is greatly reduced.

  In the heat dissipation structure 12D configured as described above, the electronic component 18 generates heat when the electronic component 18 is driven. The heat generated in the electronic component 18 is transmitted to the first heat radiating plate 16B via the first heat transfer sheet 26 and is released from the first heat radiating plate 16B.

  The heat generated in the electronic component 18 is also transmitted to the second heat radiating plate 16C via the circuit board 13 and the second heat transfer sheet 27, and is also released to the outside from the second heat radiating plate 16C. At this time, when the chassis 4 is formed of a material having high thermal conductivity such as a metal material, the heat generated in the electronic component 18 is transmitted from the second heat radiating plate 16C to the chassis 4, and the chassis 4 also Released.

  On the other hand, when the electronic component 18 is driven, the electronic component 18 generates heat and electromagnetic noise is generated from the electronic component 18 and the wiring pattern. At this time, since the first heat radiating plate 16B is connected to the ground circuit via the ground portion 13d, the influence of electromagnetic noise is reduced.

  The second heat radiating plate 16 </ b> C includes a base portion 16 i and a protruding portion 16 j protruding from the base portion 16 i toward the circuit board 13, and only the protruding portion 16 j is interposed between the circuit board 13 and the second heat transfer sheet 27. Since the base portion 16i is located at a distance from the circuit board 13, the influence of electromagnetic noise is reduced as shown in the measurement C1 (see FIG. 11).

  In the heat dissipation structure 12D, the distance between the facing surface 16h of the protrusion 16e of the first heat dissipation plate 16B and the circuit board 13 is desirably 1.2 mm or more, and the distance of the protrusion 16j of the second heat dissipation plate 16C is It is desirable that the distance between the facing surface 16k and the circuit board 13 is 1.2 mm or more.

[Summary 2]
As described above, in the heat radiating structures 12B, 12C, and 12D, the first heat radiating plate 16B has the base portion 16d and the protruding portion 16e that protrudes from the base portion 16d to the circuit board 13 side. The part 16e is connected to the circuit board 13 via the first heat transfer sheet 26, and the base part 16d is positioned away from the circuit board 13.

  Therefore, it is possible to improve the heat dissipation of heat generated in the electronic component 18 and reduce the influence of electromagnetic noise.

  In particular, when a large area metal plate is positioned in the vicinity of the electromagnetic noise generation source, the influence is great, but the large base portion 16d of the first heat radiating plate 16B is positioned away from the electromagnetic noise generation source. Therefore, the influence of electromagnetic noise can be effectively reduced.

  Moreover, since the high heat dissipation performance is ensured by making the protrusion part 16e of the 1st heat sink 16B contact the circuit board 13 via the 1st heat transfer sheet 26, the fan motor for improving heat dissipation is installed. There is no need to place them. Accordingly, it is possible to reduce the size of the electronic component 18 by reducing noise, manufacturing cost, and the number of components.

  Further, as in the heat dissipation structures 12C and 12D, high heat dissipation performance is also ensured by bringing the protruding portion 16i of the second heat dissipation plate 16C into contact with the circuit board 13 via the second heat transfer sheet 27.

  Furthermore, since the first heat radiating plate 16B and the second heat radiating plate 16C are provided in the heat radiating structures 12C and 12D, the first heat radiating plate 16B and the second heat radiating plate 16C when the electronic component 18 generates heat. Heat is released from both of the plates 16C, and high heat dissipation can be ensured.

  Further, by disposing the base portion 16i of the second heat radiating plate 16C on the outer surface side of the chassis 4 as in the heat radiating structure 12C, the heat generated in the electronic component 18 is efficiently released to the outside of the electronic device 1. Therefore, the heat dissipation can be further improved.

  In addition, by setting the distance between the facing surface 16h of the projecting portion 16e of the first heat radiating plate 16B and the circuit board 13 to 1.2 mm or more, the influence of electromagnetic noise is further increased from the result of the measurement B (see FIG. 5). Can be reduced.

  Similarly, by setting the distance between the facing surface 16k of the projecting portion 16j of the second heat radiating plate 16C and the circuit board 13 to 1.2 mm or more, the influence of electromagnetic noise is further increased from the result of the measurement B (see FIG. 5). Can be reduced.

  Further, like the heat dissipation structure 12C, the resin sheet 25 having the heat dissipation holes 25a, 25a,... Is attached to the surface opposite to the side facing the circuit board 13 in the base portion 16i of the second heat dissipation plate 16C. Thus, the finger does not come into contact with the second heat radiating plate 16C at the time of heat radiation, and it is possible to improve safety such as prevention of burns while improving heat radiation.

  Further, like the heat dissipation structure 12C, the placement recess 7a and the insertion hole 7b are formed in the chassis 4, the base portion 16i of the second heat dissipation plate 16C is disposed in the arrangement recess 7a, and the second heat dissipation plate is inserted in the insertion hole 7b. By inserting and arranging the protruding portion 16j of 16C, the second heat radiating plate 16C does not protrude downward from the lower surface of the chassis 4, and the heat radiating structure 12C is reduced in size while ensuring good heat dissipation. Can do.

  In addition, by disposing the resin sheet 25 in the arrangement recess 7a of the chassis 4 as in the heat dissipation structure 12C, it is possible to reduce the size of the heat dissipation structure 12C while improving heat dissipation and safety. it can.

  In addition, although the example which used the heat transfer sheet as both the 1st heat transfer body and the 2nd heat transfer body was shown above, the 1st heat transfer body and the 2nd heat transfer body are heat transfer. It is not restricted to a sheet | seat, For example, it is also possible to use another heat transfer body with high heat transfer rates, such as heat transfer grease, as a 1st heat transfer body and a 2nd heat transfer body.

  The specific shapes and structures of the respective parts shown in the above-described best mode are merely examples of the implementation of the present invention, and the technical scope of the present invention is limited by these. It should not be interpreted in a general way.

FIG. 2 shows measurement A together with FIG. 2, which is a cross-sectional view of the heat dissipation structure used for measurement A. It is the chart and graph figure which show the result of measurement A. FIG. 4 and FIG. 5 show the measurement B, and this figure is a perspective view of the heat dissipation structure used for the measurement B. It is sectional drawing of the thermal radiation structure used for the measurement B. It is a graph which shows the result of the measurement B. FIG. 7 to FIG. 15 show the measurement C, and this figure is a cross-sectional view of the heat dissipation structure used for the measurement C1. It is sectional drawing of another heat dissipation structure used for the measurement C1. It is sectional drawing of another heat dissipation structure used for the measurement C1. It is a conceptual diagram which shows the result of the measurement C1 about the thermal radiation structure shown in FIG. It is a conceptual diagram which shows the result of the measurement C1 about the thermal radiation structure shown in FIG. It is a conceptual diagram which shows the result of the measurement C1 about the thermal radiation structure shown in FIG. It is sectional drawing of the thermal radiation structure used for the measurement C2. It is sectional drawing of another heat dissipation structure used for the measurement C2. It is sectional drawing of another heat dissipation structure used for the measurement C2. It is sectional drawing of the heat dissipation structure used for the measurement D which does not have a heat sink, a heat spreader, and a heat sink. It is sectional drawing of the thermal radiation structure used for the measurement D which has a heat sink. It is sectional drawing of the thermal radiation structure used for the measurement D which has a heat sink and a heat spreader. It is sectional drawing of the heat dissipation structure used for the measurement D which has a heat sink, a heat spreader, and a heat sink. It is sectional drawing of the thermal radiation structure used for the measurement D which has a heat sink, the heat spreader, and the heat sink, and the chassis was formed with the metal material. It is a graph which shows the result of the measurement D. 22 to 27 show specific embodiments of the electronic apparatus and the heat dissipation structure of the present invention, and this figure is a perspective view of the electronic apparatus. It is a perspective view of the electronic device shown with the case body removed. It is a perspective view of the electronic device which shows a bottom face side. It is an expanded sectional view of the heat dissipation structure concerning a 1st embodiment. It is an expansion perspective view of a heat spreader. It is an expansion perspective view which shows the state in which the heat sink with which the heat spreader was attached was attached to the circuit board. It is sectional drawing which shows the modification of the thermal radiation structure which concerns on 1st Embodiment. It is sectional drawing which shows the thermal radiation structure which concerns on 2nd Embodiment. It is sectional drawing which shows the 1st modification of the thermal radiation structure which concerns on 2nd Embodiment. It is sectional drawing which shows the 2nd modification of the thermal radiation structure which concerns on 2nd Embodiment.

  DESCRIPTION OF SYMBOLS 1 ... Electronic device, 2 ... Outer casing, 4 ... Chassis, 7a ... Arrangement concave part, 7b ... Insertion hole, 7c ... Connection part, 12 ... Heat dissipation structure, 13 ... Circuit board, 13a ... One side, 13b ... Other Surface, 13c ... Ground part, 13d ... Grand part, 14 ... Heat sink, 15 ... Heat spreader, 16 ... Heat sink, 16a ... Base part, 16b ... Protruding part, 16c ... Opposite surface, 17 ... Component mounting part, 18 ... Electronic Components: 19 ... Heat radiation surface portion, 20 ... Mounted protrusion, 23 ... First heat transfer sheet, 24 ... Second heat transfer sheet, 25 ... Resin sheet, 25a ... Heat radiation hole, 12A ... Heat radiation structure, 4A ... Chassis 50 ... heat dissipation structure, 51 ... circuit board, 51a ... one side, 51b ... the other side, 52 ... electronic component, 53 ... heat sink, 54 ... heat transfer sheet, 60 ... heat dissipation structure, 61 ... circuit board, 61a ... one side, 63 ... Plate, 70 ... Heat dissipation structure, 73 ... Heat dissipation plate, 73a ... Base part, 73b ... Projection, 60A ... Heat dissipation structure, 60B ... Heat dissipation structure, 62 ... Electronic component, 64 ... Heat transfer sheet, 70A ... Heat dissipation structure, 73 ... Heat dissipation plate, 80A ... heat dissipation structure, 81 ... circuit board, 81a ... one surface, 81b ... the other surface, 82 ... electronic component, 83 ... chassis, 83a ... placement recess, 83b ... insertion hole, 84 ... resin sheet, 84a ... Heat dissipation hole, 80B ... Heat dissipation structure, 85 ... Heat sink, 80C ... Heat dissipation structure, 86 ... Heat transfer sheet, 87 ... Heat spreader, 87a ... Heat dissipation surface part, 87b ... Mounted projection, 80D ... Heat dissipation structure, 83D ... Chassis, 83c ... coupling part, 88 ... heat sink, 88a ... base part, 88b ... projecting part, 89 ... heat transfer sheet, 80E ... heat dissipation structure, 83E ... chassis, 12B ... heat dissipation structure, 16B ... 1 heat radiating plate, 16d: base portion, 16e: projecting portion, 16g: mounted protrusion, 16h: facing surface, 26: first heat transfer sheet (heat transfer body), 12C: heat radiating structure, 16C: second 16i ... base portion, 16j ... projecting portion, 16k ... opposing surface, 27 ... second heat transfer sheet (heat transfer body), 12D ... heat dissipation structure

Claims (20)

A circuit board which is disposed inside the outer casing and has a component mounting portion and a ground portion connected to a ground circuit, and an electronic component which is a heat source when driven on one surface of the component mounting portion;
A heat sink that is disposed on a surface side of the circuit board on which the electronic component is mounted and that releases heat generated in the electronic component;
It is arranged on the opposite side to the side on which the electronic component is mounted across the circuit board, and protrudes from the base part and the base part to the circuit board side and faces the other surface of the component mounting part. A heat sink having a protrusion formed with an opposing surface;
A first heat transfer body that is in close contact with the other surface of the component mounting portion of the circuit board and the opposing surface of the protruding portion of the heat dissipation plate and transmits heat generated in the electronic component to the heat dissipation plate; With heat dissipation structure. A heat spreader which is disposed between the circuit board and the heat sink and has a flat plate-like heat radiating surface portion and a mounted protrusion protruding from the heat radiating surface portion, and one surface of the heat radiating surface portion is in close contact with the heat sink When,
A second heat transfer body that is in close contact with the other surface of the heat spreader and the electronic component and transmits heat generated in the electronic component to the heat spreader and the heat sink;
The heat dissipation structure according to claim 1, wherein the attachment protrusion of the heat spreader is attached to a ground portion of the circuit board. A part of the outer casing is constituted by a chassis made of a metal material and having a coupling portion,
Attach the heat sink to the chassis,
The heat dissipation structure according to claim 2, wherein a coupling portion of the chassis is coupled to a ground portion of the circuit board. The heat dissipation structure according to claim 1, wherein a distance between the facing surface of the protruding portion of the heat dissipation plate and the circuit board is 1.2 mm or more. The heat dissipation structure according to claim 1, wherein a resin sheet having a heat dissipation hole is attached to a surface opposite to the surface facing the circuit board in the base portion of the heat dissipation plate. Forming an insertion hole in the chassis;
Attach the base of the heat sink to the outer surface of the chassis,
The heat dissipation structure according to claim 3, wherein the protrusion of the heat dissipation plate is inserted into the insertion hole of the chassis. Forming a placement recess in the chassis;
The insertion hole is formed at a position penetrating a part of the arrangement recess,
Placing the base of the heat sink in the placement recess,
The heat dissipation structure according to claim 6, wherein the protrusion of the heat dissipation plate is inserted into the insertion hole. A resin sheet having a heat dissipation hole is attached to a surface opposite to the surface facing the circuit board in the base portion of the heat dissipation plate,
The heat dissipation structure according to claim 7, wherein the resin sheet is arranged in the arrangement recess. An outer casing in which predetermined parts are arranged, and
A circuit board which is disposed inside the outer casing and has a component mounting portion and a ground portion connected to a ground circuit, and an electronic component which is a heat source during driving is mounted on one surface of the component mounting portion;
A heat sink that is disposed on a surface side of the circuit board on which the electronic component is mounted and that releases heat generated in the electronic component;
It is arranged on the opposite side to the side on which the electronic component is mounted across the circuit board, and protrudes from the base part and the base part to the circuit board side and faces the other surface of the component mounting part. A heat sink having a protrusion formed with an opposing surface;
A first heat transfer body that is in close contact with the other surface of the component mounting portion of the circuit board and the opposing surface of the protruding portion of the heat dissipation plate and transmits heat generated in the electronic component to the heat dissipation plate; With electronic equipment. A circuit board which is disposed inside the outer casing and has a component mounting portion and a ground portion connected to a ground circuit, and an electronic component which is a heat source when driven on one surface of the component mounting portion;
The circuit board is disposed on the surface of the circuit board on which the electronic component is mounted, and a flat base portion and a facing surface that protrudes from the base portion to the circuit board side and faces one surface of the component mounting section are formed. A first heat radiating plate having a projected portion,
A first part that is in close contact with the one surface of the component mounting part of the circuit board and the opposing surface of the protruding part of the first heat radiating plate and transmits heat generated in the electronic component to the first heat radiating plate. A heat dissipating structure comprising one heat transfer body. A mounting protrusion is provided on the first heat radiating plate,
The heat dissipation structure according to claim 10, wherein an attachment protrusion of the first heat dissipation plate is attached to a ground portion of the circuit board. The heat dissipation structure according to claim 10, wherein a distance between the facing surface of the protruding portion of the first heat dissipation plate and the circuit board is 1.2 mm or more. It is arranged on the opposite side to the side on which the electronic component is mounted across the circuit board, and protrudes from the base part and the base part to the circuit board side and faces the other surface of the component mounting part. A second heat radiating plate having a protrusion formed with an opposing surface;
The second heat transfer plate is in close contact with the other surface of the component mounting portion of the circuit board and the facing surface of the protruding portion of the second heat dissipation plate and transmits heat generated in the electronic component to the second heat dissipation plate. The heat dissipation structure according to claim 10, wherein two heat transfer bodies are provided. A part of the outer casing is constituted by a chassis made of a metal material and having a coupling portion,
Attaching the second heat sink to the chassis,
The heat dissipation structure according to claim 13, wherein the coupling portion of the chassis is coupled to a ground portion of the circuit board. The heat dissipation structure according to claim 13, wherein a distance between the facing surface of the protruding portion of the second heat dissipation plate and the circuit board is 1.2 mm or more. The heat dissipation structure according to claim 13, wherein a resin sheet having a heat dissipation hole is attached to a surface opposite to the surface facing the circuit board in the base portion of the second heat dissipation plate. Forming an insertion hole in the chassis;
A base portion of the second heat sink is attached to the outer surface of the chassis,
The heat dissipation structure according to claim 14, wherein the protrusion of the second heat dissipation plate is inserted and disposed in the insertion hole of the chassis. Forming a placement recess in the chassis;
The insertion hole is formed at a position penetrating a part of the arrangement recess,
Disposing a base portion of the second heat sink in the disposing recess;
The heat dissipation structure according to claim 17, wherein the protrusion of the second heat dissipation plate is inserted into the insertion hole. A resin sheet having a heat radiation hole is attached to a surface opposite to the surface facing the circuit board in the base portion of the second heat radiation plate,
The heat dissipation structure according to claim 18, wherein the resin sheet is arranged in the arrangement recess. An outer casing in which predetermined parts are arranged, and
A circuit board which is disposed inside the outer casing and has a component mounting portion and a ground portion connected to a ground circuit, and an electronic component which is a heat source during driving is mounted on one surface of the component mounting portion;
The circuit board is disposed on the surface of the circuit board on which the electronic component is mounted, and a flat base portion and a facing surface that protrudes from the base portion to the circuit board side and faces one surface of the component mounting section are formed. A first heat radiating plate having a projected portion,
A first heat transfer body that is in close contact with the one surface of the component mounting portion of the circuit board and the opposing surface of the protruding portion of the heat dissipation plate and transmits heat generated in the electronic component to the heat dissipation plate; With electronic equipment.

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