JP2006294754A - Heat dissipation structure of electronic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide the heat dissipation structure of an electronic apparatus which can improve heat dissipation and can suppress the movement of a thermally conductive member having flexibility. <P>SOLUTION: The heat dissipation structure of the electronic apparatus 100 has a housing 40 which is composed of a case 41 and a cover 42, a circuit substrate 20 which is arranged in the housing 40 and in which an electronic part 10 for generating heat is carried, and the thermally conductive member 30 having the flexibility and in which the heat generated by the electronic part 10 is dissipated to the cover 42 by the side of the non-carrying surface 21b of the circuit substrate 20 through the thermally conductive member 30. A through-hole 23 is formed in the loading position of the electronic part 10 to the circuit substrate 20, and a projection 45 composed of a heat dissipation material and projecting at least at the part toward the through-hole 23 is formed. The projection 45 is brought into contact with the thermally conductive member 30 in a state that the thermally conductive member 30 is arranged in the through-hole 23 by making the bottom 15a of the body part 15 of the electronic part 10 into the bottom. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a heat dissipation structure of an electronic device on which an electronic component that generates heat is mounted.

  Conventionally, an electronic device mounted on a vehicle or the like is configured by housing a circuit board on which electronic components are mounted in a housing. This electronic component includes a component that generates a large amount of heat, such as a power transistor, and it is necessary to dissipate heat generated from the electronic component. For example, Patent Document 1 includes a casing made of a heat dissipation material, a circuit board that is disposed in the casing and on which an electronic component that generates heat is mounted, and a heat conduction member that has flexibility, and is generated by the electronic component. A heat dissipation structure for an electronic device is disclosed in which heat is radiated to a housing on a circuit board non-mounting surface side of a circuit board via a heat conducting member.

In Patent Document 1, a protruding portion that protrudes from the bottom of a housing (cover) toward a mounting position of an electronic component is provided, and a front end surface of the protruding portion and a circuit board (printed substrate) corresponding to the mounting position of the electronic component A heat conductive material having flexibility is disposed between the non-mounting surface. Therefore, the heat generated by the electronic component can be radiated to the housing via the circuit board and the heat conductive material.
JP 2003-289191 A

  However, in the above configuration, heat generated by the electronic component is transmitted to the heat conductive material via the circuit board. Therefore, heat generated by the electronic components diffuses in the circuit board. Therefore, in order to improve heat dissipation, it is necessary to increase the arrangement range of the heat conductive material in contact with the non-mounting surface of the circuit board.

  Moreover, in patent document 1, the structure which prevents that it flows out to circumference | surroundings and a heat dissipation falls by providing a convex-shaped movement prevention part (frame part) in the front end surface of a protrusion part is also shown. . However, when the fluidity of the heat conducting material is high, it is also conceivable that the heat conducting material flows out from the gap between the protruding tip of the movement preventing portion and the non-mounting surface of the circuit board.

  In view of the above problems, an object of the present invention is to provide a heat dissipation structure for an electronic device that can improve heat dissipation and can suppress movement of a heat conductive member having flexibility.

  In order to achieve the above object, the inventions according to claims 1 to 17 include a casing made of a heat dissipation material, a circuit board disposed in the casing and mounted with heat generating electronic components, and a flexible heat. The present invention relates to a heat dissipation structure for an electronic device that includes a conductive member and radiates heat generated by the electronic component to a housing on the surface of the circuit board on which the electronic component is not mounted via the heat conductive member.

  First, as described in claim 1, the circuit board is provided with at least one hole portion that opens to the non-mounting surface side at the electronic component mounting position, and the housing is made of a heat dissipation material, and at least a part of the hole is formed. Protruding portions projecting toward the portion are provided, a heat conducting member is disposed in the hole, and the projecting portion is in contact with the heat conducting member.

  As described above, according to the present invention, since the hole is provided in the circuit board and the heat conducting member is disposed in the hole at the position where the electronic component is mounted, the heat transfer path from the electronic component to the housing is made shorter than before. can do. That is, heat dissipation can be improved. In addition, since the heat conduction member having flexibility is surrounded by the hole wall surface of the circuit board, the movement can be suppressed even when the fluidity is high. Note that the protruding portion may be in contact with the heat conducting member inside the hole, or may be in contact with the heat conducting member at the opening surface of the hole.

  According to a second aspect of the present invention, it is preferable that a through-hole penetrating the circuit board in the thickness direction is provided as the hole, the electronic component is the bottom, and the heat conducting member is disposed in the hole. In this case, since the heat generated by the electronic component is directly transmitted to the heat conducting member, the heat dissipation can be further improved.

  According to a third aspect of the present invention, it is preferable to dispose an electronic component (for example, a heat sink) having an integrally molded heat dissipation component so as to radiate heat toward the circuit board side. In this case, heat dissipation can be further improved.

  According to a fourth aspect of the present invention, the heat conducting member may be provided so as to coincide with the heat radiating component in the thickness direction of the circuit board. With such a configuration, heat can be radiated efficiently. At this time, as described in claim 5, the hole is preferably provided so as to coincide with the heat radiating component in the thickness direction of the circuit board. The hole is not particularly limited as long as the heat conductive member can be disposed with the electronic component as a bottom surface. However, if it is set as the structure of Claim 5, since the movement of a heat conductive member is restrict | limited by the hole side surface in the plane direction of a circuit board, it can thermally radiate efficiently.

  As described in claim 6, the protrusion may be integrally formed using the same material as the housing, or may be configured as a separate member from the housing as described in claim 7. good.

  As described in claim 8, it is preferable that at least a part of the protrusion is disposed in the hole. Since the protrusion and the heat conducting member are in contact with each other in the hole, the heat transfer path from the electronic component to the housing can be further shortened.

  According to a ninth aspect of the present invention, it is preferable that the protruding portion is provided so as to have a predetermined interval between the circuit board or the circuit board and the electronic component in a state where the protruding portion is disposed in the hole. Thereby, even if an external force is applied to the housing, the protruding portion does not contact the circuit board, so that the connection reliability between the electronic component and the circuit board is improved. The predetermined interval does not cause a problem in the electrical characteristics of the electronic device even when a predetermined external force (required vibration resistance value) is applied, and the flexible heat conduction member is between the protrusion and the hole side surface. Is set in a range that does not flow out of the hole.

  Specifically, as described in claim 10, it is preferable that the protruding portion is provided with a stepped portion facing the hole side surface of the circuit board and the periphery of the hole portion of the non-mounting surface. In this case, the heat conduction member cannot flow out of the hole from between the protruding portion and the side surface of the hole unless two orthogonal directions are used. Thus, if the outflow path of the heat conducting member is complicated, it is effective for suppressing the outflow of the heat conducting member to the outside in the predetermined direction (movement restraint).

  According to the eleventh aspect, the movement suppressing means for suppressing the movement of the heat conducting member may be provided at a portion arranged in the hole of the protruding portion. Specifically, as described in claim 12, the movement suppressing means can be at least one of a protrusion having a predetermined height and a groove having a predetermined depth.

  When the movement suppressing means is provided at the contact portion with the heat conducting member, the contact area between the heat conducting member and the protrusion increases, and the movement of the heat conducting member is caused by the anchor effect. Can be suppressed. At that time, as described in claim 14, it is more effective to provide the movement suppressing means in a frame shape.

  Further, as described in claim 15, the protruding portion may be provided so that a part of the protruding portion is in contact with the circuit board and covers the entire opening surface of the hole portion on the non-mounting surface side. In this case, at least the outflow of the heat conducting member to the outside of the hole can be completely suppressed. In addition, when the heat conductive member or the heat conductive member and the protrusion are arranged in the hole without a gap, the movement of the heat conductive member can be completely prevented. In addition, a part of the protruding portion may be disposed in the hole portion, or may be disposed only on the opening surface without being disposed in the hole portion.

  At that time, as described in claim 16, the protruding portion is fitted into the hole portion. In this case, since the circuit board can be fixed to the protrusion provided in the case, a fixing means for fixing the circuit board to the housing can be made unnecessary. Specifically, as described in claim 17, for example, the protruding portion is provided with a stepped portion facing the hole side surface of the circuit board and the periphery of the non-mounting surface hole, and the stepped portion is formed in the hole of the circuit board. It is good to comprise so that it may fit.

  Next, the invention described in claims 18 to 23 includes a housing, a circuit board that is disposed in the housing and on which an electronic component that generates heat is mounted, and a heat conduction member having flexibility, and the electronic component. This invention relates to a heat dissipation structure of an electronic device in which heat generated by the heat dissipation is radiated to a non-mounting surface side of a circuit board via a heat conducting member.

  According to an eighteenth aspect of the present invention, the circuit board is provided with at least one hole opening at least on the non-mounting surface side at the mounting position of the electronic component, and the heat conduction member is disposed in the hole. One end of the heat radiating member is fixed to the circuit board so as to be in contact with the member, and heat is radiated from the other end of the heat radiating member to the internal space of the housing.

  For example, if the electronic device is placed in a high temperature environment and the internal temperature of the housing is lower than the external temperature of the housing, the heat generated by the electronic components is diffused into the internal space of the housing rather than dissipating to the housing Is more advantageous. In such a case, when the structure of the present invention is applied, heat can be efficiently radiated to the internal space of the housing by a heat radiating member (for example, a heat radiating fin: heat sink).

  The operational effects of the inventions according to claims 19 to 22 are the same as the operational effects of the inventions according to claims 2 to 5, so the description thereof is omitted.

  According to a twenty-third aspect, the heat dissipating member may be provided so that a part of the heat dissipating member contacts the circuit board and covers the entire opening surface of the hole on the non-mounting surface side. In this case, at least the outflow of the heat conducting member to the outside of the hole can be completely suppressed. Moreover, when a heat conductive member or a heat conductive member and a heat radiating member are arrange | positioned in a hole part without a clearance gap, the movement of a heat conductive member can be prevented completely. A part of the heat dissipating member may be disposed in the hole, or may be disposed only in the opening surface without being disposed in the hole.

  In addition, in the invention in any one of Claims 1-23, as a heat conductive member which has a softness | flexibility, as shown in Claim 24, a thermal radiation gel or thermal radiation grease can be applied.

  In addition, the invention according to any one of claims 1 to 24 can be applied to an electronic device mounted on a vehicle as described in claim 25. Electronic devices mounted on vehicles, especially electronic devices mounted on engine rooms, etc., have severe conditions of use such as temperature. Therefore, by applying the heat dissipation structure of the present invention, heat dissipation is improved and more suitable. It becomes.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
1A and 1B are diagrams for explaining a schematic configuration of an electronic device according to the present embodiment, where FIG. 1A is a cross-sectional view, and FIG. 1B is a cross-sectional view taken along line AA in FIG. (C) is a plan view of the AA cross section of (a) as viewed from above (seen in the cover direction). In FIG. 1B, for convenience, the bottom surface of the main body of the electronic device and the heat sink are shown by broken lines. The electronic device shown in the present embodiment is used as a vehicle engine ECU (Electric Control Unit).

  As shown in FIG. 1, the electronic device 100 includes a circuit board 20 on which an electronic component 10 that generates heat is mounted, a heat transfer member 30, and a housing 40 that houses the circuit board 20 and the heat transfer member 30. is doing.

  The electronic component 10 is a heat generating element that generates excessive heat by an operation such as a power transistor, for example, and is molded with a resin 14 together with a heat sink 11, a lead frame 12, a bonding wire 13, and the like as heat radiating components. The molded electronic component 10 is mounted so as to dissipate heat toward the circuit board 20 via the heat sink 11. Specifically, the heat sink 11 is disposed between the electronic component 10 and the circuit board 20 in a state where the lead frame 12 is connected to lands (described later) on the surface of the circuit board 20 via, for example, solder.

  As the heat sink 11, a material having a higher thermal conductivity than the resin 14 (for example, 20 to 400 W / m · K) can be used. In the present embodiment, the heat sink 11 has a substantially rectangular shape in the plane direction of the circuit board 10 as shown in FIG. Further, a surface 15a of the main body portion 15 of the molded electronic component 10 facing the circuit board 20 (hereinafter referred to as a bottom surface 15a of the main body portion 15) is also the same as the heat sink 11 and large as shown in FIG. It has a substantially rectangular shape with a different height. Note that the bottom surface 15a of the main body portion 15 of the molded electronic component 10 corresponds to the bottom surface of the electronic component on which the heat conducting member shown in the claims is arranged.

  The circuit board 20 has an electronic component such as a microcomputer, a power transistor, a resistor, a capacitor, etc. (in this embodiment, excessive heat generated by the operation) on a board 21 formed with wiring patterns (not shown) and via holes for connecting the wiring patterns. Only the electronic component 10 to be shown is mounted). And it is fixed to the housing 40. In the present embodiment, a substrate made of, for example, an epoxy resin is used as the substrate 21. The substrate 21 is not limited to the above configuration, and other resin substrates and ceramic substrates can be applied. Reference numeral 22 denotes a land as a connection electrode with the lead frame 12.

  The circuit board 20 is provided with a through-hole 23 that penetrates from the mounting surface 21a of the electronic component 10 to the non-mounting surface 21b that is the back surface thereof at the mounting position of the electronic component 10. The size of the through hole 23 in the planar direction of the circuit board 20 is determined based on the heat dissipation properties of the heat conducting member 30 (the heat conductivity of the heat conducting member 30 and the amount of arrangement with respect to the electronic component 10). In the present embodiment, the through hole 23 has a substantially rectangular shape that is the same as the heat sink 11 and has a different size, as shown in FIG. In the state in which the electronic device 100 is configured, the heat sink 11 is completely included in the formation range of the through hole 23 in the thickness direction of the circuit board 20 (the outer periphery (side wall surface) of the through hole 23 and the heat sink 11. The through hole 23 is completely included in the formation range of the bottom surface 15a of the main body part 15 (the outer periphery of the bottom surface 15a of the main body part 15 and the outer periphery of the through hole 23). (The side wall surface) has a certain distance over the entire circumference).

  Further, in the annular facing portion between the bottom surface 15 a of the main body portion 15 and the peripheral region (the mounting surface 21 a side) of the through hole 23 of the circuit board 20, heat conduction is performed from the gap between the main body portion 15 and the circuit board 20. An outflow prevention member 24 for preventing the member 30 from flowing out is disposed. In the present embodiment, an adhesive is applied as the outflow prevention member 24, and the adhesive is arranged in an annular shape with no gap between the opposing portions, and the main body portion 15 is bonded and fixed to the circuit board 20.

  The heat conducting member 30 serves not only to transmit the heat generated by the electronic component 10 to the housing 40, but also to reduce vibrations transmitted to the electronic component 10 when an external force is applied to the housing 40. Therefore, it is composed of a material having flexibility, that is, fluidity rather than a complete solid. When a material having flexibility (low viscoelasticity) is applied, the electronic component 10 and a protruding portion (described later) provided on the housing 40 can be reliably brought into close contact with each other via the heat conducting member 30. That is, heat dissipation can be improved. Moreover, since it has a softness | flexibility, even if the space | interval of the electronic component 10 and a protrusion part is not constant, stress can concentrate on the local part of the electronic component 10, and it can prevent that a failure | damage arises. Furthermore, since it does not harden like an adhesive, thermal stress is not applied to the electronic component 10.

In the present embodiment, the heat conducting member 30 is disposed in the through hole 23 of the circuit board 20 with the bottom surface 15a of the main body portion 15 of the electronic component 10 as the bottom. That is, the movement of the heat conducting member 30 is suppressed by the bottom surface 15 a of the main body portion 15 of the electronic component 10, the outflow prevention member 24, and the side wall surface of the through hole 23. However, in the present embodiment, the protruding portion of the casing 40 described later does not completely seal the through hole 23 and has a predetermined gap between the through hole 23 and the protruding portion. Therefore, regardless of the arrangement of the electronic device 100, it is preferable that the heat conducting member 30 be made of a material having a relatively high viscosity that is difficult to flow out of the through hole 23 from the gap. For example, a heat dissipating gel whose viscosity is adjusted to 800 to 1500 Pa · sec can be applied. This heat dissipation gel is based on silicon and has improved thermal conductivity by adding a metal oxide (for example, 60 to 90 wt% of zinc oxide). In this embodiment, an 800 Pa · sec heat dissipation gel was applied. In addition to the heat dissipation gel, for example, heat dissipation grease can be applied as the heat conducting member 30. The housing 40 is made of a metal material such as aluminum, for example. The cover 41 has a substantially rectangular plate shape that closes the open surface of the case 41. The case 41 and the cover 42 are integrated by a fixing means 43 to form an internal space 44 that accommodates the circuit board 20 and the heat conducting member 30. In the present embodiment, the case 41 and the cover 42 are integrated by a screw as a fixing means 43 that penetrates the substrate 21 in a state where the circuit board 20 is sandwiched between the case 41 and the cover 42.

  The cover 42 is provided with a protrusion 45 that protrudes from the bottom of the cover 42 toward the through hole 23 (the mounting position of the electronic component 10) of the circuit board 20. The protrusion 45 in the present embodiment is provided in a substantially trapezoidal shape by press molding with respect to the cover 42 so that a predetermined range from the tip surface 45a to the inclined portion 45b is disposed in the through hole 23 of the circuit board 20. ing. Therefore, since it is integrally molded with the cover 42, molding is easy. Further, the rectangular front end surface 45a is parallel to the surface of the circuit board 20, and the electronic device 100 is configured in the thickness direction of the circuit board 20 as shown in FIG. Further, the front end surface 45 a substantially coincides with the heat sink 11. A recess 46 corresponding to the shape of the protrusion 45 is provided on the back side of the protrusion 45.

  Further, the protruding portion 45 is disposed in the through hole 23 of the circuit board 20, has a predetermined interval with the bottom surface 15 a of the main body portion 15 of the electronic component 10, and is closest to the protruding portion 45. In the part which has it, it is comprised so that it may have a predetermined space | interval with the side wall surface of the through-hole 23. FIG. The distance between the bottom surface 15a (that is, the protruding height of the protruding portion 45) corresponds to the thickness of the heat conducting member 30 disposed between the front end surface 45a of the protruding portion 45 and the bottom surface 15a of the electronic component 10. . In other words, the distance from the bottom surface 15 a is such that the heat conducting member 30 can efficiently dissipate heat without being thermally saturated, and when an external force is applied to the housing 40 from the outside, It is set within a range in which the stress transmitted from the projecting portion 45 to the electronic component 10 can be reduced so that no abnormality occurs in the characteristics. Specifically, even if the electronic component 10 is at a predetermined temperature or lower (eg, 110 ° C. or lower) and an upper limit value of external force determined from the product specifications (product warranty) is applied, no abnormality occurs in the electrical characteristics. Set by range. In the present embodiment, the distance from the bottom surface 15a is set to 0.5 mm.

  In addition, the distance between the through hole 23 and the side wall surface is such that when an external force is applied to the housing 40 from the outside, the electrical property of the electronic device 100 is not changed from the protruding portion 45 to the electronic component 10. The transmitted stress can be reduced, and the heat conduction member 30 having flexibility is set within a range in which the heat conduction member 30 having flexibility does not flow out between the protrusion 45 and the side wall surface of the through hole 23. In the present embodiment, the distance from the side wall surface of the through hole 23 is also set to 0.5 mm.

  An example of the procedure for assembling the electronic device 100 described above is shown below. First, as an outflow prevention member 24, an adhesive is annularly disposed around the through hole 23 in the mounting surface 21a of the circuit board 20, and the main body portion 15 of the electronic component 10 is bonded and fixed to the circuit board 20 with the bottom surface 15a facing down. . Further, the lead frame 12 of the electronic component 10 and the land 22 of the circuit board 20 are connected by, for example, solder. As a result, the electronic component 10 is mounted on the circuit board 20.

  After this mounting, a heat radiating gel as the heat conducting member 30 is placed in the through hole 23 with the bottom surface 15a of the electronic component 10 as the bottom. At this time, the heat conducting member 30 is in a state where the cover 42 is assembled to the case 41 (a state in which the protruding portion 45 is disposed in the through hole 23), and at least the front end surface 45a of the protruding portion 45 and the bottom surface 15a of the electronic component 10. An amount that is arranged without a gap is arranged. The electronic device 100 is configured by assembling the cover 42 to the case 41 by fastening the screw 43 so as to accommodate the circuit board 20.

  In the present embodiment, the heat conduction member 30 has an amount larger than a predetermined interval between the front end surface 45a and the bottom surface 15a of the protrusion 45 and does not leak from the through hole 23 even if the protrusion 45 is disposed. Is disposed in the through hole 23. Accordingly, when a predetermined range from the front end surface 45a of the projecting portion 45 is disposed in the through hole 23 during assembly, the heat conducting member 30 contacts not only the front end surface 45a of the projecting portion 45 but also a part of the inclined portion 45b. It will be. With such a configuration, the contact area between the heat conducting member 30 and the protrusion 45 increases, and the movement of the heat conducting member 30 can be further suppressed.

  Thus, according to the heat dissipation structure of the electronic device 100 in this embodiment, the through hole 23 is provided in the circuit board 20, the bottom surface 15 a of the main body 15 of the electronic component 10 is the bottom, and the heat conducting member 30 is the through hole 23. The protrusion 45 provided on the cover 42 is in contact with the heat conducting member 30. That is, the heat generated by the electronic component 10 is directly transmitted to the heat conducting member 30 and released to the outside of the housing 40 through the protrusion 45. Therefore, in the configuration in which the heat generated by the electronic component 10 is radiated to the cover 42 which is the casing 40 on the non-mounting surface 21b side of the circuit board 20 through the heat conducting member 30, the heat dissipation is improved as compared with the conventional case. be able to.

  Moreover, since the heat conductive member 30 is surrounded by the side wall surface of the through-hole 23 provided in the circuit board 20, the movement of the heat conductive member 30 having flexibility can be suppressed.

  Further, a part of the tip surface 45 a and the inclined part 45 b of the protrusion 45 is arranged in the through hole 23, and the tip surface 45 a and a part of the inclined part 45 b are in contact with the heat conducting member 30 in the through hole 23. It is configured. Therefore, the heat transfer path from the electronic component 10 to the housing 40 can be further shortened, and the heat dissipation can be further improved.

  Further, the protruding portion 45 is disposed in the through hole 23 of the circuit board 20, has a predetermined interval with the bottom surface 15 a of the main body portion 15 of the electronic component 10, and is closest to the protruding portion 45. In the part which has it, it is comprised so that it may have a predetermined space | interval with the side wall surface of the through-hole 23. FIG. Therefore, heat can be efficiently radiated and the connection reliability between the electronic component 10 and the circuit board 20 is improved.

  Note that the heat generated by the electronic component 10 is directly radiated to the housing 40 via the heat conducting member 30, and the electronic component 10 is mounted on the circuit board 20 on the back side of the heat sink 11 arrangement. A configuration using a so-called reverse package in which the heat conducting member 30 is disposed between the surface on the heat sink 11 arrangement side and the housing 40 is also conceivable. However, when the reverse package is applied, the external force applied to the housing 40 is concentrated on the electronic component 10, and there is a possibility that the electrical characteristics of the electronic device 100 may be abnormal. On the other hand, in the present embodiment, when an external force is applied to the housing 40, the vibration transmitted from the protrusion 45 to the heat conducting member 30 is distributed to the electronic component 10 and the circuit board 20. Yes. Therefore, the configuration is stronger against external force than the above configuration. Further, the movement of the heat conducting member 30 can be suppressed by the side wall surface of the through hole 23. Therefore, the degree of freedom of arrangement is improved as compared with the above configuration.

  In the present embodiment, a configuration example in which a part of the protrusion 45 is disposed inside the through hole 23 and the protrusion 45 contacts the heat conducting member 30 inside the through hole 23 is shown. However, the distance between the front end surface 45a of the protrusion 45 and the bottom surface 15a of the electronic component 10 can efficiently radiate heat without causing the heat conducting member 30 to be thermally saturated, and an external force can be applied to the housing 40. In this case, it is only necessary that the stress transmitted from the protrusion 45 to the electronic component 10 can be reduced so that no abnormality occurs in the electrical characteristics of the electronic device 100.

  Therefore, for example, when the substrate 21 of the circuit board 20 is thin, as shown in FIG. 2, the heat conducting member 30 is disposed up to the full opening surface of the through hole 23 on the non-mounting surface side, and the non-mounting surface 21b. It is good also as a structure which makes the front-end | tip surface 45a of the protrusion part 45 and the heat conductive member 30 contact in the opening surface. FIG. 2 is a view showing a modification of the present embodiment, and is an enlarged cross-sectional view of only the characteristic part of the electronic device 100 after assembly.

  Further, in the present embodiment, the heat sink 11 is completely included in the thickness direction of the circuit board 20 (the interval between the outer periphery (side wall surface) of the through hole 23 and the side surface of the heat sink 11 is constant over the entire periphery). The example in which the heat conduction member 30 is disposed in contact with the side wall surface of the through hole 23 in a state where the through hole 23 is formed as shown in FIG. However, the heat conducting member 30 may be disposed so as to be in contact with at least the bottom surface 15 a of the main body portion 15 of the electronic component 10 and the protruding portion 45. More preferably, it may be disposed so as to contact at least a part of the bottom surface 15 a of the main body portion 15 corresponding to the heat sink 11 and the protruding portion 45. More preferably, the heat conductive member 30 is disposed so as to completely include the heat sink 11 in the thickness direction of the circuit board 20, and heat is efficiently transmitted to the heat conductive member 30 through the heat sink 11. . Therefore, as shown in FIG. 2, the heat conducting member 30 may be arranged so as to coincide with the heat sink 11. Even with such a configuration, heat can be radiated efficiently. In this case, as shown in FIG. 2, the through hole 23 may be configured to coincide with the heat sink 11. In this case, the movement of the heat conducting member 30 in the planar direction of the circuit board 20 can be suppressed on the side wall surface of the through hole 23.

  Further, the heat conducting member 30 may be disposed between the bottom surface 15 a corresponding to the heat sink 11 of the electronic component 10 and the tip surface 45 a of the protruding portion 45 so as not to contact the side wall surface of the through hole 23. In the example shown in FIGS. 3A and 3B, the heat sink 11, the heat conducting member 30, and the tip surface 45 a of the projecting portion 45 coincide with each other in the thickness direction of the circuit board 20. With such a configuration, heat can be radiated efficiently. Further, since the heat conducting member 30 is disposed in the through hole 23, the movement of the circuit board 20 in the planar direction can be suppressed. 3A and 3B are diagrams illustrating a modification of the present embodiment, in which FIG. 3A is a cross-sectional view in which only a characteristic portion of the electronic device 100 after assembly is enlarged, and FIG. 3B is a cross-sectional view taken along line BB in FIG. It is the top view which looked at from the bottom (viewed in the case direction). However, in the case of the above configuration, the heat conducting member 30 may move within the range of the through hole 23 in the planar direction of the circuit board 20. On the other hand, when the heat conducting member 30 shown in the present embodiment is arranged in contact with the side wall surface of the through hole 23, it is more effective for suppressing the movement of the heat conducting member 30 in the plane direction of the circuit board 20. In addition, the contact area between the heat conducting member 30 and the protruding portion 45 can be made substantially constant, and a structure without unevenness in heat dissipation can be achieved.

  Moreover, in this embodiment, the example which arrange | positions the adhesive agent as the flow prevention member 24 in the opposing area | region of the bottom face 15a of the electronic component 10 and the mounting surface 21a of the circuit board 20 was shown. However, since it is only necessary to prevent the heat conduction member 30 from leaking into the internal space 44 on the case 41 side, as shown in FIGS. 2 and 3, a part of the region facing the bottom surface 15 a and the mounting surface 21 a of the circuit board 20 is provided. There may be a gap. Furthermore, as shown in FIG. 4, the gap between the opposing regions of the bottom surface 15a of the electronic component 10 and the mounting surface 21a of the circuit board 20 is large enough to prevent the heat conducting member 30 having a predetermined viscosity from leaking out. If it exists, it can also be set as the structure which does not arrange | position the flow prevention member 24. FIG. In this case, for example, it can be applied to the sheet-like heat conducting member 30 having a high viscosity. FIG. 4 is a view showing a modification of the present embodiment, and is an enlarged cross-sectional view of only the characteristic portion of the electronic device 100 after assembly.

  Moreover, in this embodiment, the example in which the protrusion part 45 was integrally formed by the press molding in the cover 42 which comprises the housing | casing 40 was shown. However, as shown in FIG. 5, the protrusion 45 may be configured as a separate part. In this case, the protrusion 45 can be made of a material different from that of the cover 42 (for example, a material having higher thermal conductivity than the cover 42). The protrusion 45 is fixed to the cover 42 by a fixing means made of a conductive material (for example, a screw made of a conductive adhesive or a metal material). FIG. 5 is a view showing a modification of the present embodiment, and is an enlarged cross-sectional view of only the characteristic part of the electronic device 100 after assembly.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 6 is an enlarged cross-sectional view of only the characteristic portion of the electronic device 100 after assembly.

  Since the heat dissipation structure of the electronic device 100 according to the second embodiment is common in common with that according to the first embodiment, detailed description of the common parts will be omitted, and different parts will be described mainly.

  The second embodiment is different from the first embodiment in that the protruding portion 45 is provided with a stepped portion facing the side wall surface of the through hole 23 of the circuit board 20 and the periphery of the through hole of the non-mounting surface 21b. is there.

  As shown in FIG. 6, the projecting portion 45 is provided in a stepped shape that increases in diameter from the distal end surface 45 a toward the cover 42. Specifically, in the thickness direction of the circuit board 20, a constant interval is included in the through-hole 23 (between the outer periphery (side wall surface) of the through-hole 23 and the end portion of the tip surface 45 a over the entire periphery). A first step portion forming surface 45c that is connected to the tip surface 45a in a direction perpendicular to the tip surface 45a and faces the side wall surface of the through hole 23, and a first step portion forming surface 45c. And a second step portion constituting surface 45d facing the periphery of the through hole of the non-mounting surface 21b of the circuit board 20. It is connected to the cover 42 via a third step portion forming surface 45e which is connected in a vertical direction to the second step portion forming surface 45d and parallel to the first step portion forming surface 45c. In addition, the protrusion part 45 in this embodiment is integrally formed in the cover 42 by die-casting.

  Then, in a state where the electronic device 100 is configured, the first stepped portion forming surface 45c has a predetermined distance from the opposing side wall surface of the through hole 23, and the second stepped portion forming surface 45d is opposed. A predetermined interval is provided between the non-mounting surface 21b of the circuit board 20 and the periphery of the through hole. In addition, the space | interval between the 1st step part structure surface 45c and the side wall surface of the through-hole 23 which opposes, and the through-hole periphery of the non-mounting surface 21b of the circuit board 20 which opposes the 2nd step part structure surface 45d Is determined from the result of the vibration test shown in the first embodiment. In the present embodiment, the distance between the front end surface 45a and the bottom surface 15a of the electronic component 10 is 0.5 mm, and the distance between both is also set to 0.5 mm.

  Thus, in the present embodiment, the heat conducting member 30 cannot flow out of the through hole 23 unless two orthogonal directions are interposed. Thus, by complicating the outflow path of the heat conducting member 30, the outflow (movement) of the heat conducting member 30 to the vibration in a predetermined direction is more effectively suppressed than in the case where the protrusion 45 has a substantially trapezoidal shape. can do.

(Third embodiment)
Next, a third embodiment of the present invention will be described with reference to FIG. FIG. 7 is an enlarged cross-sectional view of only the characteristic portion of the electronic device 100 after assembly.

  Since the heat dissipation structure of the electronic device 100 according to the third embodiment is common in common with that according to the first embodiment, detailed description of the common parts will be omitted, and different parts will be described mainly.

  The third embodiment is different from the first embodiment in that a heat dissipating member for further improving heat dissipation is disposed on the back side of the protruding portion 45.

  For example, as shown in the first embodiment, when the protrusion 45 is integrally provided on the cover 42 by press molding, a recess 46 corresponding to the shape of the protrusion 45 is provided on the back side of the protrusion 45. It is done. Therefore, in the present embodiment, the heat dissipating fins 50 are arranged in the recessed portions 46. A part of the heat radiation fin 50 is fixed to the inner wall surface of the recess 46 by a fixing means made of a conductive material (for example, a screw made of a conductive adhesive or a metal material). With such a configuration, heat dissipation can be further improved. In particular, in the case of press molding, the recessed portion 46 is inevitably provided, so that the heat radiating fin 50 can be stably disposed on the cover 42 using the recessed portion 46.

  In addition, arrangement | positioning of the radiation fin 50 is not limited only to the recessed part 46 formed by press molding. Further, the shape of the recessed portion 46 does not have to correspond to the protruding portion 45. In other molding methods (for example, die casting), the recessed portion 46 can be intentionally provided on the back side of the protruding portion 45, and the radiation fin 50 can be disposed.

(Fourth embodiment)
Next, the 4th Embodiment of this invention is described based on FIGS. FIG. 8 is an enlarged cross-sectional view of only the characteristic part of the electronic device 100 after assembly. FIGS. 9A and 9B are plan views showing the distal end surface 45a of the protrusion 45. FIG. FIG. 10 is a diagram showing a modification of the present embodiment, and is an enlarged cross-sectional view of only the characteristic portion of the electronic device 100 after assembly.

  Since the heat dissipation structure of the electronic device 100 according to the fourth embodiment is common in common with that according to the first embodiment, detailed description of the common parts will be omitted, and different parts will be described mainly.

  The fourth embodiment is different from the first embodiment in that a movement suppressing portion that suppresses the movement of the heat conducting member 30 is provided in a portion arranged in the through hole 23 of the protruding portion 45. This movement prevention unit corresponds to the movement prevention means shown in the claims.

  As shown in FIG. 8, in the present embodiment, a protrusion 47 a having a predetermined height in the direction of the electronic component 10 is provided on the front end surface 45 a in contact with the heat conducting member 30 as a movement preventing unit. As shown in FIGS. 8 and 9A, the protrusion 47a is provided in a rectangular frame shape so as to surround the periphery of the front end surface 45a of the protrusion 45. In the present embodiment, the protrusion 47a is formed integrally with the protrusion 45. Further, the height of the protrusion 47a is determined from the results of the heat generation test and the vibration test shown in the first embodiment.

  With such a configuration, the contact area between the protrusion 45 and the heat conducting member 30 increases, and the movement of the heat conducting member 30 can be more efficiently suppressed by the so-called anchor effect. Moreover, since it is provided in a frame shape, it is possible to suppress the movement of the heat conducting member 30 evenly (no gaps) in the planar direction of the circuit board 20.

  The protrusion 47a is not limited to a frame shape. What is necessary is just to be provided in the site | part arrange | positioned at the through-hole 23 of the protrusion part 45, and to suppress the movement of the heat conductive member 30. FIG. For example, one protrusion 47a may be provided on the tip surface 45a, but a plurality of protrusions 47a may be provided as shown in FIG. Further, the formation position of the protrusion 47 a is not limited to the portion in contact with the heat conducting member 30. If it is a site | part arrange | positioned at the through-hole 23 of the protrusion part 45, it will become a wall at the time of the heat conductive member 30 moving (outflow), and the movement can be suppressed.

  Moreover, in this embodiment, the example of the projection part 47a was shown as a movement prevention part. However, it is not limited to the said structure. For example, as shown in FIG. 10, a groove 47b having a predetermined depth may be provided. In the present embodiment, the groove 47 b is provided in a rectangular frame shape so as to surround the periphery of the tip end surface 45 a of the protrusion 45, and is integrally formed with the protrusion 45. Further, the depth of the groove 47b is determined from the results of the heat generation test and the vibration test. Also in this case, since the contact area between the protrusion 45 and the heat conducting member 30 increases, the movement of the heat conducting member 30 can be more efficiently suppressed. Further, in the case of the groove portion 47b, the distance from the bottom surface 15a of the electronic component 10 is increased in the direction opposite to the protruding portion 47a, so that both heat dissipation and connection reliability between the electronic component and the circuit board are achieved. Above, it is more advantageous than the protrusion 47a. The groove 47b is not limited to a frame shape.

(Fifth embodiment)
Next, the 5th Embodiment of this invention is described based on FIGS. 11A is a cross-sectional view in which only the characteristic portion of the electronic device 100 after assembly is enlarged, and FIG. 11B is a cross-sectional view taken along the line CC of FIG. (C) is a plan view, (c) is a plan view of the CC cross section of (a) as viewed from above (as viewed in the cover direction). In FIG. 11B, for convenience, the bottom surface 15a of the electronic device 10 and the heat sink 11 are illustrated by broken lines. 12 and 13 are diagrams showing a modification of FIG.

  Since the heat dissipation structure of the electronic device 100 according to the fifth embodiment is common in common with that according to the first embodiment, the detailed description of the common parts will be omitted below, and different parts will be mainly described.

  The fifth embodiment is different from the first embodiment in that the entire opening surface of the through hole 23 on the non-mounting surface 21b side is blocked by the protrusion 45.

  As shown in FIG. 11, the protrusion 45 in the present embodiment is provided in a staircase shape whose diameter increases from the tip surface 45 a toward the cover 42 as shown in the second embodiment. Specifically, as shown in FIGS. 11A to 11C, in the thickness direction of the circuit board 20, the tip surface 45a is provided so as to substantially coincide with the cross-section of the through-hole 23. Connected to the first step portion constituting surface 45c facing the side wall surface of the through hole 23 and the first step portion constituting surface 45c perpendicularly to the non-mounting surface 21b of the circuit board 20. And a second step portion constituting surface 45d facing the periphery of the through hole. Moreover, it connects with the cover 42 through the 3rd step part structure surface 45e parallel to the 2nd step part structure surface 45d and parallel to the 1st step part structure surface 45c. In addition, the protrusion part 45 in this embodiment is integrally formed in the cover 42 by die-casting.

  At the time of assembly, the protruding portion 45 is press-fitted into the through hole 23, the first step portion constituting surface 45c is in contact with the side wall surface of the through hole 23, and the second step portion constituting surface 45d is a non-mounting surface of the circuit board 20. It is fitted and fixed in contact with the periphery of the through hole 21b. In this state, the heat conducting member 30 is sealed in an internal space constituted by the bottom surface 15 a of the electronic component 10, the side wall surface of the through hole 23, the outflow preventing member 24, and the tip end surface 45 a of the protruding portion 45. . Therefore, the heat conduction member 30 does not leak out of the through hole 23. Thus, according to the heat dissipation structure of the electronic device 100 shown in the present embodiment, not only can the heat dissipation be improved, but also the movement of the heat conducting member 20 can be completely suppressed.

  Further, the protrusion 45 is fitted and fixed to the through hole 23 of the circuit board 20. That is, the fixed substrate 20 is fixed to the cover 42. Therefore, the circuit board 20 can be fixed to the housing 40 without applying a separate fixing means.

  In addition, the structure of the protrusion part 45 which block | closes the whole opening surface by the side of the non-mounting surface 21b of the through-hole 23 is not limited to the said example. Any structure that can block the entire opening surface by partly contacting the circuit board 20 may be used. For example, as shown in FIG. 12, in the thickness direction of the circuit board 20, the through hole 23 is included (the space between the outer periphery (side wall surface) of the through hole 23 and the end portion of the tip surface 45a is constant over the entire periphery. The front end surface 45a may be provided so that the front end surface 45a is in annular contact with the periphery of the opening of the non-mounting surface 21b of the through hole 23. In this case, by disposing the heat conducting member 30 up to the opening surface of the non-mounting surface 21 b of the through hole 23, heat dissipation can be improved and the heat conducting member 30 is prevented from flowing out of the through hole 23. be able to.

  Further, in the configuration shown in FIG. 11, the projecting portions 45 are provided in a stepped manner, the first step portion constituting surface 45 c is in contact with the side wall surface of the through hole 23, and the second step portion constituting surface 45 d is not on the circuit board 20. An example in which the periphery of the through hole of the mounting surface 21b is in contact with and fixed to the through hole 23 is shown. However, the configuration in which the protrusion 45 is fixed to the through hole 23 is not limited to the above example. For example, as shown in FIG. 13, in the thickness direction of the circuit board 20, the protruding portion 45 provided with the tip surface 45 a is press-fitted into the through hole 23 so that the tip surface 45 a substantially coincides with the cross section of the through hole 23. It is good also as a structure fixed by.

(Sixth embodiment)
Next, a sixth embodiment of the present invention will be described with reference to FIG. 14A is a cross-sectional view in which only the characteristic part of the electronic device 100 after assembly is enlarged, and FIG. 14B is a cross-sectional view taken along the line DD in FIG. It is a plan view. In FIG. 14B, for convenience, the bottom surface 15a of the electronic device 10 and the heat sink 11 are illustrated by broken lines.

  Since the heat dissipation structure of the electronic device 100 in the sixth embodiment is in common with that in the first embodiment, the detailed description of the common parts will be omitted below, and different parts will be mainly described.

  The sixth embodiment is different from the first embodiment in that a heat dissipating member that is in contact with the heat conducting member 30 arranged at one end in the through hole 23 is fixed to the circuit board 20, and the internal space 44 in the housing 40 is fixed. It is the point which was set as the structure which thermally radiates.

  The heat radiating member 60 shown in FIGS. 14A and 14B is made of a material having a higher thermal conductivity than that of the heat conducting member 30, and in this embodiment, it is made as a heat radiating fin made of a metal material. . Specifically, a front end surface 60a that is parallel to the surface of the circuit board 20 and substantially coincides with the cross-section and size and shape of the through hole 23, a fin portion 60b composed of a plurality of fins, and a side wall surface of the through hole 23 It is comprised by the connection part 60c which opposes and connects the front end surface 60a and the fin part 60b. A predetermined range (at least a part of the connecting part 60c or a part of the connecting part 60c and the fin part 60b) is bonded and fixed to the side wall surface of the through hole 23 from the front end surface 60a.

  In this fixed state, the heat conducting member 30 disposed in the through hole 23 is in contact with the bottom surface 15 a of the electronic component 10 and the front end surface 60 a of the heat radiating member 60. Therefore, according to the heat dissipation structure of the electronic device 100 shown in the present embodiment, the heat generated by the electronic component 10 is not directly transmitted to the heat conducting member 30 but is also transmitted to the heat radiating member 60 through the heat conducting member 30. Is done. Then, the transmitted heat is diffused from the fin portion 60 b to the internal space 44 of the housing 40.

  For example, when the electronic device 100 is disposed in a high temperature environment and the internal space 44 of the housing 40 is lower than the external temperature of the housing 44, the housing is more radiated than the heat generated by the electronic component 10 is radiated to the housing 40. It is advantageous to diffuse into 40 internal spaces 44. In such a case, when the heat dissipation structure shown in this embodiment is applied, the heat dissipation member 60 can efficiently dissipate heat to the internal space 44 of the housing 40.

  Further, since the heat conducting member 30 is sealed by the bottom surface 15a of the electronic component 10, the side wall surface of the through hole 23 of the circuit board 20, the outflow preventing member 24, and the heat radiating member 60 (tip surface 60a), the through hole 23 is provided. Will not leak outside. Further, since the heat conducting member 30 is disposed in the space formed by the bottom surface 15 a of the electronic component 10, the side wall surface of the through hole 23 of the circuit board 20, the outflow prevention member 24, and the heat radiating member 60, the heat conducting member 30. Can be completely prevented.

  In the present embodiment, an example in which a part of the heat radiating member 60 (a predetermined range from the front end surface 60a) is disposed and fixed inside the through hole 23 is shown. However, in the thickness direction of the circuit board 20, the through hole 23 is included (the outer periphery (side wall surface) of the through hole 23 and the end of the front end surface 60 a have a constant interval over the entire periphery). It is good also as a structure which provides the front end surface 60a and seals the front end surface 60a by making an annular contact around the opening of the non-mounting surface 21b of the through hole 23. Further, the heat dissipation member 60 may be configured not to completely seal the opening surface of the non-mounting surface 21 b of the through hole 23.

  Although the preferred embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and can be implemented with various modifications.

  In the present embodiment, a configuration in which the through hole 23 is provided in the circuit board 20 and the heat generated by the electronic component 10 is directly transmitted to the heat conducting member 30 is shown. However, the hole in which the heat conducting member 30 is disposed is not limited to the through hole 23. Any configuration may be used as long as a hole opening at least on the non-mounting surface 21b of the circuit board 20 is provided at the mounting position of the electronic component 10 and the heat conducting member 30 is disposed in the hole. Therefore, it may be a non-through hole (groove). In this case, although the effect is inferior to that of the through hole 23, the heat dissipation can be improved as compared with the conventional configuration in which the heat conduction member 30 is transmitted via the circuit board 20. Furthermore, the movement suppression of the heat conductive member 30 having flexibility on the hole wall surface can be improved.

  Further, in the present embodiment, in the planar direction of the circuit board 20, the heat sink 11, the bottom surface 15 a of the main body portion 15 of the electronic component 10, the through hole 23, and the front end surface 45 a of the protruding portion 45 are arranged. An example of the same rectangular shape (different in size) is shown. However, the shape is not limited to the above example. Also, each may have a different shape. However, if the shape is the same, waste in each positional relationship can be eliminated, and the physique of the electronic device 100 can be reduced in size.

  Moreover, in this embodiment, the example which provides one through-hole 23 with respect to one electronic component 10 was shown. However, the number of through holes 23 as the hole is not limited to the above example. A plurality of through holes 23 may be provided for one electronic component 10, and heat may be transmitted to at least one protrusion 45 via the heat conducting member 30 disposed in each through hole 23.

It is a figure for demonstrating schematic structure of the electronic device in 1st Embodiment, (a) is sectional drawing, (b) looked at the AA cross section of (a) from the lower side (looking in the case direction). (C) is a plan view, (c) is a plan view of the AA cross section of (a) as viewed from above (as viewed in the cover direction). It is a figure which shows a modification, and is sectional drawing which expanded only the characteristic part among the electronic devices after an assembly | attachment. It is a figure which shows a modification, (a) is sectional drawing which expanded only the characteristic part among the electronic devices after an assembly | attachment, (b) looked at the BB cross section of (a) from the lower side (case direction) FIG. It is a figure which shows a modification, and is sectional drawing which expanded only the characteristic part among the electronic devices after an assembly | attachment. It is a figure which shows a modification, and is sectional drawing which expanded only the characteristic part among the electronic devices after an assembly | attachment. It is sectional drawing to which only the characteristic part was expanded among the electronic devices after an assembly | attachment, in order to demonstrate schematic structure of the electronic device in 2nd Embodiment. It is sectional drawing to which only the characteristic part was expanded among the electronic devices after an assembly | attachment, in order to demonstrate schematic structure of the electronic device in 3rd Embodiment. It is sectional drawing to which only the characteristic part was expanded among the electronic devices after an assembly | attachment, in order to demonstrate schematic structure of the electronic device in 4th Embodiment. (A), (b) is a top view which shows the front end surface of a protrusion part. It is a figure which shows a modification, and is sectional drawing which expanded only the characteristic part among the electronic devices after an assembly | attachment. It is a figure for demonstrating schematic structure of the electronic device in 5th Embodiment, (a) is sectional drawing which expanded only the characteristic part among the electronic devices after an assembly | attachment, (b) is B of (a). The -B section is a plan view seen from the bottom (viewed in the case direction), and (c) is a plan view of the section BB of (a) seen from the top (viewed in the cover direction). It is a figure which shows a modification, and is sectional drawing which expanded only the characteristic part among the electronic devices after an assembly | attachment. It is a figure which shows a modification, and is sectional drawing which expanded only the characteristic part among the electronic devices after an assembly | attachment. It is a figure for demonstrating schematic structure of the electronic device in 6th Embodiment, (a) is sectional drawing which expanded only the characteristic part among the electronic devices after an assembly | attachment, (b) is C of (a). It is the top view which looked at -C cross section from the lower side (viewed in the case direction).

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Electronic component 11 ... Heat sink 15 ... Main-body part 15a ... Bottom surface (of main-body part) 20 ... Circuit board 21 ... Substrate 21a ... Mounting surface 21b ... Non-mounting Surface 23 ... through hole (hole)
24 ... Outflow prevention member 30 ... Heat conduction member 40 ... Housing 41 ... Case 42 ... Cover 44 ... Internal space 45 ... Projection 45a ... Tip surface 100 ..Electronic devices

Claims (25)

A housing made of heat dissipation material;
A circuit board disposed in the housing and mounted with heat-generating electronic components;
A heat conduction member having flexibility,
In the heat dissipation structure of the electronic device, the heat generated by the electronic component is radiated to the housing on the non-mounting surface side of the electronic component of the circuit board via the heat conducting member.
The circuit board is provided with at least one hole that opens to the non-mounting surface side at the mounting position of the electronic component,
The housing is made of a heat dissipation material, and provided with a projecting portion at least a portion projecting toward the hole,
A heat dissipation structure for an electronic device, wherein the heat conductive member is disposed in the hole, and the protrusion is in contact with the heat conductive member. As the hole, a through hole that penetrates the circuit board in the thickness direction is provided,
The heat dissipation structure for an electronic device according to claim 1, wherein the heat conducting member is disposed in the hole portion with the electronic component as a bottom surface. The electronic component has an integrally molded heat dissipation component,
The heat dissipation structure for an electronic device according to claim 1, wherein the electronic component is disposed so as to dissipate heat toward the circuit board.   4. The heat dissipation structure for an electronic device according to claim 3, wherein the heat conducting member is arranged to coincide with the heat dissipation component in the thickness direction of the circuit board. 5.   The heat dissipation structure for an electronic device according to claim 4, wherein the hole portion is provided so as to coincide with the heat dissipation component in the thickness direction of the circuit board.   6. The heat dissipation structure for an electronic device according to claim 1, wherein the protruding portion is integrally formed using the same material as the housing.   The heat dissipation structure for an electronic device according to claim 1, wherein the protruding portion is configured as a separate member from the housing.   8. The heat dissipation structure for an electronic device according to claim 1, wherein at least a part of the protrusion is disposed in the hole.   9. The electronic device according to claim 8, wherein the protrusion is provided so as to have a predetermined interval between the circuit board or the circuit board and the electronic component in a state where the protruding part is disposed in the hole. The heat dissipation structure of the device.   10. The heat dissipation structure for an electronic device according to claim 9, wherein the protruding portion is provided with a step portion facing the hole side surface of the circuit board and the periphery of the hole portion of the non-mounting surface.   11. The heat dissipation of the electronic device according to claim 8, wherein a movement suppressing unit that suppresses movement of the heat conducting member is provided at a portion of the protruding portion that is disposed in the hole. Construction.   12. The heat dissipation structure for an electronic device according to claim 11, wherein the movement suppressing means is at least one of a protrusion having a predetermined height and a groove having a predetermined depth.   13. The heat dissipation structure for an electronic device according to claim 11, wherein the movement suppressing unit is provided at a contact portion with the heat conducting member.   14. The heat dissipation structure for an electronic device according to claim 13, wherein the movement suppressing means is provided in a frame shape.   9. The projecting portion according to claim 1, wherein a part of the projecting portion is in contact with the circuit board so as to block the entire opening surface of the hole portion on the non-mounting surface side. Heat dissipation structure for electronic devices.   16. The heat dissipation structure for an electronic device according to claim 15, wherein the protrusion is fitted into the hole.   The projecting portion is provided with a step portion facing the hole side surface of the circuit board and the periphery of the non-mounting surface hole portion, and the step portion is fitted into the hole portion of the circuit board. 16. A heat dissipation structure for an electronic device according to 16. A housing,
A circuit board disposed in the housing and mounted with heat-generating electronic components;
A heat conduction member having flexibility,
In the heat dissipation structure of the electronic device, the heat generated by the electronic component is radiated to the non-mounting surface side of the electronic component of the circuit board through the heat conducting member.
The circuit board is provided with at least one hole opening at least on the non-mounting surface side at the mounting position of the electronic component,
In a state where the heat conducting member is arranged in the hole, one end of the heat radiating member is fixed to the circuit board so as to contact the heat conducting member, and heat is radiated from the other end to the internal space of the housing. A heat dissipation structure for an electronic device. As the hole, a through hole that penetrates the circuit board in the thickness direction is provided,
19. The heat dissipation structure for an electronic device according to claim 18, wherein the heat conducting member is disposed in the hole portion with the electronic component as a bottom surface. The electronic component has an integrally molded heat dissipation component,
20. The heat dissipation structure for an electronic device according to claim 18, wherein the electronic component is arranged to dissipate heat toward the circuit board.   21. The heat dissipation structure for an electronic device according to claim 20, wherein the heat conducting member is arranged so as to coincide with the heat dissipation component in the thickness direction of the circuit board.   The heat dissipation structure for an electronic device according to claim 21, wherein the hole is provided so as to coincide with the heat dissipation component in the thickness direction of the circuit board.   23. The heat dissipation member according to any one of claims 18 to 22, wherein a part of the heat dissipation member is in contact with the circuit board so as to block the entire opening surface of the hole on the non-mounting surface side. Heat dissipation structure for electronic devices.   The heat dissipation structure for an electronic device according to any one of claims 1 to 23, wherein a heat dissipation gel or a heat dissipation grease is applied as the heat conducting member.   It is applied to the electronic device mounted in the vehicle, The heat dissipation structure of the electronic device of any one of Claims 1-24 characterized by the above-mentioned.

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