JP2006100803A - Electronic control unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electronic control unit capable of suppressing the deterioration of radiative property by securing a radiation path through a radiation member even if external force such as shock or vibration is applied. <P>SOLUTION: A circuit substrate 11 on which electronic parts including a heater element 12 is accommodated in a cubicle 1, and the heater element 12 and the cubicle 1 are thermally connected by interposing the radiation member 30 between the heater element 12 and the internal surface of the cubicle 1. As the radiation member 30, a polymer material having fluidity is used, and a film 40 that the radiation member 30 and the cubicle 1 are chemically or electrically bonded, which prevents the radiation member 30 from moving, is disposed between the radiation member 30 and the internal surface of the cubicle. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a heat dissipation structure in an electronic control unit (ECU).

  A circuit board (printed circuit board) 110 on which an electronic component 111 is mounted is arranged in the housing of the electronic control device as shown in FIG. 21, and is generated from a heating element 112 mounted on the circuit board 110 as shown in FIG. It is known to dissipate heat to the housing 100 via the heat dissipating member 101. Particularly in the vehicle ECU, the heat dissipating member 101 is often used as a means for cooling the heat generating element 112 that becomes high in temperature. The heat radiating member 101 is usually made of an elastic material such as rubber, or a resin adhesive or grease with improved heat radiating properties, and is sandwiched between the casing 100 and the heating element 112 as shown in FIG. Used in. Alternatively, as shown in FIG. 23, the heat dissipation member 101 is used by being sandwiched between the housing 100 and the circuit board 110.

The heating element 112 described here is an element that generates high heat by flowing a large current, and normally, a power MOS transistor, a power diode, or the like is used.
Recently, an SMD type element of a MOS transistor has been developed, and a small component capable of handling a large current is mounted on a circuit board, and it is important to develop a technology for cooling the small component with a small heat radiation area. It was. This part is an important part that controls other parts with a large current in terms of the function of the ECU, and is also a part that determines the quality in terms of product quality.

  On the other hand, when a material having fluidity such as gel is used as the heat radiating member 101, there is an advantage that cracks do not occur even when stress is applied. On the other hand, when external force such as impact or vibration is applied. The heat radiating member 101 or the housing 100 receives the external force, and the heat radiating member 101 moves from a predetermined position, so that the target heat radiating property cannot be exhibited.

As a method for preventing the heat radiating member 101 from moving, there is a method for increasing the surface roughness of the housing surface. However, if a material having fluidity is used as the heat radiating member 101, it is difficult to suppress the movement of the heat radiating member 101. Further, as disclosed in Example 3 of Patent Document 1, there is a method in which a protrusion (dam) is provided on the arrangement surface of the heat dissipation member 101 to make it difficult to move the heat dissipation member 101. However, in this method, since the arrangement of the heating elements 112 must be specified, a small amount of various types of casings 100 are used for the circuit board 110 having various types of arrangements of the heating elements 112, thereby reducing the cost of the casing 100. It will cause to raise.
JP 2003-289191 A

  The present invention has been made under such a background, and its purpose is to secure a heat radiation path through the heat radiation member even when an external force such as an impact or vibration is applied to suppress a decrease in heat radiation performance. An object of the present invention is to provide an electronic control device that can perform the above-described operation.

  The electronic control device according to claim 1 uses a polymer material having fluidity as the heat radiating member, and between the heat radiating member and the housing inner surface or the pedestal surface, Alternatively, a film that is electrically coupled to prevent movement of the heat radiating member is provided. Therefore, by using a flowable polymer material as the heat radiating member, cracks do not occur even when stress is applied, and in this case, when external force such as shock or vibration is applied to the heat radiating member or the case Further, the movement of the heat radiating member is blocked by the film that chemically or electrically couples with the heat radiating member and the housing or the pedestal to block the movement of the heat radiating member. As a result, even when an external force such as an impact or vibration is applied, a heat dissipation path through the heat dissipation member can be secured to prevent a decrease in heat dissipation.

  The electronic control device according to claim 2 uses a polymer material having fluidity as the heat radiating member, and chemically connects the heat radiating member and the heat generating element or the circuit board between the heat radiating member and the heat generating element or the circuit board. Alternatively, a film that is electrically coupled to prevent movement of the heat radiating member is provided. Therefore, by using a flowable polymer material as the heat radiating member, cracks do not occur even when stress is applied, and in this case, when external force such as shock or vibration is applied to the heat radiating member or the case Further, the movement of the heat radiating member is blocked by the film that is chemically or electrically coupled to the heat radiating member and the heat generating element or the circuit board to block the movement of the heat radiating member. As a result, even when an external force such as an impact or vibration is applied, a heat dissipation path through the heat dissipation member can be secured to prevent a decrease in heat dissipation.

  The electronic control device according to claim 3 uses a polymer material having fluidity as the heat radiating member, and between the heat radiating member and the housing inner surface or the pedestal surface, Alternatively, a film that is electrically coupled to prevent movement of the heat radiating member is disposed, and further, chemically or electrically coupled to the heat radiating member and the heat generating element or circuit board between the heat radiating member and the heat generating element or circuit board. Thus, a film for preventing the movement of the heat radiating member is provided. Therefore, by using a flowable polymer material as the heat radiating member, cracks do not occur even when stress is applied, and in this case, when external force such as shock or vibration is applied to the heat radiating member or the case Further, the movement of the heat radiating member is blocked by the film that chemically or electrically couples with the heat radiating member and the housing or the pedestal to block the movement of the heat radiating member. Further, when an external force such as impact or vibration is applied to the heat radiating member or the housing, the heat radiating member is formed by a film that chemically or electrically couples with the heat radiating member and the heating element or the circuit board to prevent the heat radiating member from moving. Movement is prevented. As a result, even when an external force such as an impact or vibration is applied, a heat dissipation path through the heat dissipation member can be secured to prevent a decrease in heat dissipation.

  According to a fourth aspect of the present invention, in the electronic control device according to the first or third aspect of the present invention, a film for preventing the movement of the heat radiating member is disposed on the entire surface of the housing inner surface or the pedestal surface where the heat generating element can be disposed. Then, since the film | membrane which prevents a movement is arrange | positioned at the various places of a housing | casing or a base, a common housing | casing can be used with respect to the circuit board from which arrangement | positioning of a heat generating element differs.

  As described in claim 5, in the electronic control device according to claim 1 or 3, do not place a film on the inner surface of the housing or the surface of the pedestal where heat dissipation is not necessary, on a film that prevents movement of the heat dissipation member. In this case, the cost can be reduced.

  As described in claim 6, in the electronic control device according to any one of claims 1 to 5, when a silicone-based resin material is used as a heat dissipation member, silicone is used in relation to a film that prevents movement. The functional group of the resin material can be involved in chemical bonding or electrical bonding.

  As described in claim 7, in the electronic control device according to any one of claims 1 to 5, when an epoxy resin material is used as the heat dissipating member, epoxy is used in relation to the film that prevents movement. The functional group of the resin material can be involved in chemical bonding or electrical bonding.

  As described in claim 8, in the electronic control device according to any one of claims 1, 3 to 7, when a metal material is used as a material of the housing or the pedestal, the film that prevents movement is used. In relation, the hydroxyl group on the metal material side can be involved in chemical bonding or electrical bonding. In particular, as described in claim 9, in the electronic control device according to claim 8, when aluminum is used as the metal material, the hydroxyl group on the aluminum material side is chemically changed in relation to the film that prevents movement. It can be involved in coupling or electrical coupling.

  As described in claim 10, in the electronic control device according to any one of claims 1, 3 to 7, when resin is used as a material on at least the surface of the housing or the pedestal, movement is prevented. In relation to the film to be bonded, the functional group of the resin can be involved in chemical bonding or electrical bonding.

  As described in claim 11, in the electronic control device according to any one of claims 1 to 10, when a material having a benzene ring or a hydrocarbon long chain is used as a film that prevents movement of the heat dissipation member. The high temperature material properties can be improved by the benzene ring, and the low temperature material properties can be improved by the hydrocarbon long chain. Thereby, for example, in a vehicle-mounted electronic control device, it is possible to form a film that prevents movement suitable for the mounting environment.

  In particular, as described in claim 12, in the electronic control device according to claim 11, as a material having a benzene ring or a hydrocarbon long chain, polymethyl polybenzene alcohol, polymethyl polybenzene amine, polymethyl polybenzene Any of epoxy, polymethylpolybenzenesulfonic acid, and polyethylpolybenzene alcohol may be used.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is an exploded view of the electronic control device according to this embodiment. FIG. 2 is a perspective view of the electronic control device in a state where the upper case 3 of FIG. 1 is not present. FIG. 3 shows a heat dissipation structure of an electronic component (heat generating element) mounted on a circuit board. The electronic control device in this embodiment is a vehicle-mounted electronic control device, and is a device for controlling a vehicle-mounted engine. That is, the engine control ECU.

  The housing (case) 1 includes a lower case 2 and an upper case 3. The casing 1 (the lower case 2 and the upper case 3) is made of iron or aluminum. Alternatively, a resin may be used as a material on at least the surface of the housing 1 (the lower case 2 and the upper case 3). Specifically, it is the case where the entire casing is made of resin, or the case where resin coating is applied to the metal surface. The lower case 2 has a rectangular flat plate shape. The upper case 3 has a square box shape with an open bottom surface. And it arrange | positions so that the opening part of the upper case 3 may be plugged up with the lower case 2, and the lower case 2 and the upper case 3 are screwed, for example.

  Inside the housing 1, a circuit board 11 on which the electronic component 10 is mounted is accommodated in a horizontal state (sideways). Electronic components 10 are mounted on the upper and lower surfaces of the circuit board 11 by soldering. The electronic component 10 includes a heating element 12, and the heating element 12 is disposed on the lower surface of the circuit board 11. With respect to the circuit board 11, as shown in FIG. 3, the circuit board 11 uses a multilayer substrate, and insulating layers and conductive layers are alternately laminated. In addition, via holes are formed in the circuit board 11 and the via holes are filled with a conductor 11a. A ceramic substrate or an epoxy substrate is used as a base material of the circuit board 11. 3, the heating element 12 is a package component, the chip 12a is molded with the resin 12b, the lead frame 12c protrudes from the resin 12b, and the lead frame 12c is the surface layer of the circuit board 11. Soldered to the conductive layer. A power transistor, a power diode, or the like is built in the chip 12a.

In this way, the circuit board 11 on which the electronic component 10 including the heating element 12 is mounted is accommodated in the housing 1.
A connector 20 is attached to the housing 1, and pins of the connector 20 are electrically connected to the circuit board 11. A battery, various sensors, and an engine control actuator are connected to the electronic control device (circuit board 11) through a wire through a connector 20 outside the housing 1. The electronic control unit detects the operating state of the engine based on the sensor signal, executes various calculations, and drives an actuator such as an injector or an igniter to operate the engine in an optimal state.

  Further, as shown in FIG. 3, the heat generating element 12 and the casing 1 are disposed with a heat radiating member 30 interposed between the heat generating element 12 and the inner surface of the casing 1 (the upper surface of the lower case 2). Are thermally coupled. Specifically, as the heat radiating member 30, a gel-like substance in which a metal oxide is added as a filler to a resin material as a base material is used, and as the heat radiating member 30, a fluid polymer material is used. Yes. Furthermore, the film | membrane 40 is arrange | positioned between the thermal radiation member 30 and the housing | casing inner surface. The film 40 is chemically or electrically coupled to the heat radiating member 30 and the housing 1 to prevent the heat radiating member 30 from moving in the lateral direction. 3, in the case of heat transfer from the element back surface of FIG. 3 to the lower case 2 via the heat dissipating member 30, the chip 12 a is placed on the back surface side (side facing the lower case 2) of the heat generating element 12. The heat radiating plate 12d for releasing the heat generated in the step is molded with the resin 12b so as to be in direct contact with the chip 12a, and one side (one side) is exposed to the outside so as to be in direct contact with the heat radiating member 30.

  Instead of the structure that radiates heat from the back surface of the element as shown in FIG. 3, it may be applied to a structure that radiates heat from the circuit board 11 as shown in FIG. Specifically, the heat generating element 12 and the housing 1 are thermally coupled by interposing a heat conductive heat dissipation member 30 between the circuit board 11 and the inner surface of the housing 1 (the upper surface of the lower case 2). ing. At this time, a large number of via holes are formed in the arrangement region of the heat generating elements 12 in the circuit board 11, and the heat generated in the heat generating elements 12 by the conductor 11a filled in the via holes is the back surface of the circuit board 11 (the lower surface in FIG. 4). Easy to communicate with. Moreover, in the circuit board 11, the conductor pattern 11b is formed in the contact part with the heat radiating member 30, and it is easy to transmit heat. The conductor pattern 11b may be omitted when heat transfer is sufficiently achieved.

  Further, the movement blocking film 40 of FIG. 3 is disposed by applying it to the upper surface of the lower case 2 and has a thickness of about several μm to several tens of μm. Therefore, the heat radiating member 30 can be fixed without extremely reducing the heat radiating efficiency. The reason why the thickness of the movement blocking film 40 is several μm to several tens of μm is that if the thickness is too thick, the heat dissipation efficiency decreases, and if it is too thin, it cannot be applied uniformly.

  As shown in FIG. 5, the movement prevention film 40 is disposed on the entire surface of the housing inner surface (specifically, the upper surface of the lower case 2) where the heat generating element 12 (heat radiating member 30) can be disposed. That is, it arrange | positions to all the inner surfaces (upper surface of the lower case 2) of the housing | casing 1 which the heat radiating member 30 contacts. As a result, the same fixing effect can be obtained regardless of the coordinates of the heating element 12 on the circuit board 11, and the common housing 1 can be used.

  Further, as shown in FIG. 6 instead of FIG. 5, the movement blocking film 40 may not be disposed at a location where heat radiation is unnecessary on the inner surface of the housing (the upper surface of the lower case 2). As shown in FIG. 5 and FIG. 6, since the movement blocking film 40 is applied to the housing 1, after the housing design is completed, the heat radiating member 30 is disposed only on the heat generating elements 12 that require heat dissipation. It can be changed as much as possible, the design change is easy, and the development cost of the design change is low. For example, after the evaluation of the thermal performance of the ECU, the heat radiating member 30 can be disposed only in the heat generating element 12 that requires heat dissipation, thereby reducing development costs. In addition, for example, the movement blocking film 40 can be arranged in a limited position as shown in FIG. 6 in consideration of the balance between material costs and process equipment depreciation costs. That is, in the comparison between FIG. 5 and FIG. 6, when the cost of the movement blocking film 40 is lower than the equipment amortization cost for partial coating, heat is generated on the inner surface of the casing (the upper surface of the lower case 2) as shown in FIG. The movement preventing film 40 is disposed over the entire portion where the element 12 (heat dissipation member 30) can be disposed. Further, when the cost of the movement blocking film 40 is higher than the equipment depreciation cost of the partial application, the arrangement of the heating element 12 (heat radiating member 30) on the inner surface of the casing (the upper surface of the lower case 2) as shown in FIG. The movement blocking film 40 is partially disposed only at the location.

  Further, instead of FIG. 3, as shown in FIG. 7, a heat radiating member having thermal conductivity between the heating element 12 (or the circuit board 11) and the surface of the pedestal 50 thermally coupled to the housing 1. 30 may be applied when the heating element 12 and the housing 1 are thermally coupled with each other. Specifically, in FIG. 7, a pedestal 50 is fixed in the housing 1 with screws 51. Here, the pedestal 50 may be separate from the casing 1 or may be integrated with the casing 1 as shown in FIG. 8 (the pedestal 55 may be integrally formed on the inner surface of the casing 1). .

Next, a chemical bond between the movement prevention film 40 and the heat dissipation member 30 when a silicone material (silicone resin material) is used for the heat dissipation member 30 of FIG. 3 will be described.
As shown in Chemical Formula 1, the silicone material has a hydroxyl group or a methyl group as a functional group, or has an ether bond. Therefore, as shown in FIG. 9A, the methyl group in the heat radiating member 30 and the epoxy group in the movement blocking film 40 are bonded by a covalent bond by a ring-opening reaction. Alternatively, as shown in FIG. 9B, the hydroxyl groups in the heat radiating member 30 and the hydroxyl groups in the movement blocking film 40 are bonded by a covalent bond due to a dehydration reaction. Alternatively, as shown in FIG. 9C, the hydroxyl groups in the heat dissipation member 30 and the methyl groups in the movement blocking film 40 are bonded by a covalent bond by a dehydration reaction. Alternatively, as shown in FIG. 9 (d), they are bonded by a covalent bond by a dehydration reaction between a methyl group in the heat dissipation member 30 and a hydroxyl group in the movement blocking film 40.

  Thus, by the functional group (methyl group, hydroxyl group) of the heat dissipation member 30 and the functional group of the movement blocking film 40, by a condensation reaction or a ring-opening reaction, by a hydrogen bond, an intermolecular force bond, an ionic bond, a covalent bond, etc. The heat radiating member (silicone material) and the film 40 are combined. That is, the functional group of the silicone-based resin material is involved in chemical bonding in relation to the movement blocking film 40 in the heat dissipation member 30.

次に、放熱部材３０にエポキシ系材料（エポキシ系樹脂材料）を使用する場合における、移動阻止膜４０と放熱部材３０の化学結合について説明する。

Next, a chemical bond between the movement prevention film 40 and the heat dissipation member 30 when using an epoxy material (epoxy resin material) for the heat dissipation member 30 will be described.

  As shown in Chemical Formula 2, the epoxy-based material has a hydroxyl group, a methyl group, and an epoxy group as functional groups. Therefore, as shown in FIG. 10A, the epoxy group in the heat radiating member 30 and the methyl group in the movement blocking film 40 are bonded by a covalent bond by a ring-opening reaction. Alternatively, as shown in FIG. 10 (b), the hydroxyl groups in the heat dissipation member 30 and the hydroxyl groups in the movement blocking film 40 are bonded by a covalent bond by a dehydration reaction. Alternatively, as shown in FIG. 10 (c), the hydroxyl group in the heat radiating member 30 and the methyl group in the movement blocking film 40 are bonded by a covalent bond due to a dehydration reaction. Alternatively, as shown in FIG. 10 (d), they are bonded by a covalent bond by a dehydration reaction between a methyl group in the heat dissipation member 30 and a hydroxyl group in the movement blocking film 40.

  As described above, hydrogen bonds, intermolecular force bonds, ionic bonds, and covalent bonds are formed by the condensation reaction or ring-opening reaction by the functional groups (methyl group, hydroxyl group, epoxy group) of the heat dissipation member 30 and the functional groups of the movement blocking film 40. The heat radiating member (epoxy-based material) and the film 40 are bonded by, for example. That is, the functional group of the epoxy resin material is involved in chemical bonding in relation to the movement blocking film 40 in the heat dissipation member 30.

次に、放熱部材３０にシリコーン系材料を使用する場合における、電気的結合により移動阻止膜４０と放熱部材３０を結合する場合について説明する。

Next, the case where the movement prevention film 40 and the heat radiating member 30 are coupled by electrical coupling in the case where a silicone material is used for the heat radiating member 30 will be described.

  As described above, the silicone material has a hydroxyl group or a methyl group as a functional group, or has an ether bond. Therefore, as shown in FIG. 11 (a), the bias of the charge between the methyl group in the heat dissipation member 30 and the epoxy group in the movement blocking film 40, that is, the methyl group having a positive charge δ + and the negative charge. It is linked by an epoxy group bearing a δ-. Alternatively, as shown in FIG. 11B, the charge bias between the hydroxyl group in the heat radiating member 30 and the hydrogen in the movement blocking film 40, that is, the hydrogen having a positive charge δ + and the negative charge δ− Bonded by a hydroxyl group. Alternatively, as shown in FIG. 11C, the charge bias between the hydroxyl group in the heat dissipating member 30 and the methyl group in the movement blocking film 40, that is, the methyl group carrying the positive charge δ + and the negative charge δ. It is bonded by a hydroxyl group having a minus sign. Alternatively, as shown in FIG. 11D, the charge bias between the methyl group in the heat dissipation member 30 and the hydroxyl group in the movement blocking film 40, that is, the methyl group having a positive charge δ + and the negative charge δ. It is bonded by a hydroxyl group having a minus sign.

  In this way, the charge bias between the functional group (methyl group, hydroxyl group) of the heat dissipation member 30 and the functional group of the movement blocking film 40, that is, a positive charge δ + and a negative charge δ−. Bonds due to the bias of the charge of things. That is, the functional group of the silicone-based resin material is involved in electrical coupling in relation to the movement blocking film 40 in the heat dissipation member 30.

Next, the case where the movement prevention film 40 and the heat radiating member 30 are coupled by electrical coupling when using an epoxy-based material for the heat radiating member 30 will be described.
As described above, the epoxy-based material has a hydroxyl group, a methyl group, and an epoxy group as functional groups. Therefore, as shown in FIG. 12A, the charge bias between the epoxy group in the heat dissipation member 30 and the methyl group in the movement blocking film 40, that is, the methyl group having a positive charge δ + and the negative charge. It is linked by an epoxy group bearing a δ-. Alternatively, as shown in FIG. 12B, the charge bias between the hydroxyl group in the heat dissipating member 30 and the hydrogen in the movement blocking film 40, that is, the hydrogen having a positive charge δ + and the negative charge δ− Bonded by a hydroxyl group. Alternatively, as shown in FIG. 12C, the charge bias between the hydroxyl group in the heat dissipating member 30 and the methyl group in the movement blocking film 40, that is, a methyl group bearing a positive charge δ + and a negative charge δ. It is bonded by a hydroxyl group having a minus sign. Alternatively, as shown in FIG. 12D, the charge bias between the methyl group in the heat dissipation member 30 and the hydroxyl group in the movement blocking film 40, that is, the methyl group having a positive charge δ + and the negative charge δ. It is bonded by a hydroxyl group having a minus sign.

  In this way, the charge bias in the functional group (methyl group, hydroxyl group, epoxy group) of the heat dissipation member 30 and the functional group of the movement blocking film 40, that is, the positive charge δ + and the negative charge δ− Bonds due to the bias of the charge of the objects. That is, the functional group of the epoxy resin material is involved in the electrical coupling in relation to the movement blocking film 40 in the heat dissipation member 30.

Next, the chemical or electrical coupling between the movement blocking film 40 and the housing 1 when a metal material (for example, aluminum) is used for the housing 1 will be described.
As shown in FIG. 13A, the metal surface on the housing 1 side usually has a hydroxyl group, and is bonded by a covalent bond by a dehydration reaction between a methyl group in the movement blocking film 40 and a hydroxyl group on the housing metal side. Alternatively, as shown in FIG. 13B, the hydroxyl group in the movement blocking film 40 and the hydroxyl group on the housing metal side are bonded by a covalent bond by a dehydration reaction. Alternatively, as shown in FIG. 13C, the hydrogen is bonded by a covalent bond by a dehydration reaction between hydrogen in the movement blocking film 40 and a hydroxyl group on the housing metal side.

  In this way, the hydroxyl group, methyl group, or hydrogen in the movement blocking film 40 is chemically bonded to the hydroxyl group present on the metal surface on the housing side. That is, the hydroxyl group on the metal material (for example, aluminum) side is involved in chemical bonding in relation to the movement blocking film 40 in the housing 1.

  Alternatively, as shown in FIG. 14A, the charge bias between the methyl group in the movement blocking film 40 and the hydroxyl group on the housing metal side, that is, the methyl group having a positive charge δ + and the negative charge. Bonding is performed by a hydroxyl group bearing δ-. Alternatively, as shown in FIG. 14 (b), a charge bias between hydrogen in the movement blocking film 40 and a hydroxyl group on the housing metal side, that is, hydrogen having a positive charge δ + and negative charge δ−. Bonded by a hydroxyl group bearing

  In this manner, the methyl group or hydrogen in the movement blocking film 40 is electrically coupled with the hydroxyl group present on the metal surface on the housing side. That is, the hydroxyl group on the metal material (for example, aluminum) side is involved in electrical coupling in relation to the movement blocking film 40 in the housing 1.

  In addition, when the entire casing is made of resin or resin coating is applied to the metal surface, a chemical bond or an electrical bond is made with the movement blocking film 40 using a functional group appearing on the surface of the resin material. Like that. In other words, when a resin is used as a material on at least the surface of the housing or the pedestal, the functional group of the resin is involved in chemical bonding or electrical bonding in relation to the movement blocking film 40.

  Here, the difference in characteristics between the heat dissipation member 30 and the movement blocking film 40 will be mentioned. The heat dissipating member 30 also includes functional groups such as a methyl group and a hydroxyl group. However, by giving priority to desired characteristics such as heat dissipating characteristics, for example, the bonding with the housing 1 is not sufficient for bonding with the housing 1. Therefore, in the present embodiment, a movement prevention film 40 that functions as a buffer (inclusion) for coupling between the heat dissipation member 30 and the housing 1 is disposed. The movement blocking film 40 is made of a hydrocarbon long chain as a base material, and the bias of the negative charge δ− or the positive charge δ + of the functional group is larger than that of the heat radiating member 30 so as to be electrically coupled. It is designed to increase the chemical bond and increase the chemical reactivity. Chemical reactivity is promoted by applying energy for exceeding the potential energy for reaction, and one factor is to increase the bias of charge. Therefore, the movement prevention film 40 is more electrically connected to the heat radiating member 30 and the metal or resin that is the housing than the electric coupling force or chemical reactivity between the heat radiating member 30 and the metal or resin that is the housing. It can be said that the chemical bond strength is high or the chemical reactivity is high and the chemical bond strength is high. Although it is considered that the electrical bond and the chemical bond occur at the same time, as described above, the movement blocking film 40 has a higher electrical bond force or chemical bond force than the heat dissipation member 30. Is important to.

  Furthermore, as shown in FIG. 15, the interface between the movement prevention film 40 and the heat dissipation member 30 may be cured. That is, the surface layer portion 40a of the movement blocking film 40 and the surface layer portion 30a of the heat dissipation member 30 are cured portions. For this curing, the movement blocking film 40 and the heat dissipation member 30 are brought into contact with each other and then left for a while or heated to be cured.

  At this time, it is not desirable to completely cure the heat dissipation member 30 in the thickness direction. This is because peeling occurs due to a difference in linear expansion between the heating element 12 (or the circuit board 11) and the heat dissipation member 30. However, this is not the case when there is no difference in the linear expansion difference.

When the electronic control device is mounted on a vehicle and the electronic control device is disposed in the engine room, the temperature environment is severe. In that case, do as follows.
The usage environment of the electronic control device is −40 to 150 ° C. In such specifications, for example, an aluminum alloy, iron, an iron plate resin-coated product, a polyamide resin material, or a polybutylene terephthalate resin material is used as the casing material. Note that an inexpensive material such as polypropylene may be used as long as the mounting location is not so severe. Moreover, as a base material in the heat radiating member 30, a silicone resin and an epoxy resin are used.

  Further, as the material of the migration prevention film 40 suitable for this, for example, a material having phenol, alcohol, carboxylic acid, carboxylate, thiocarboxylic acid, sulfonic acid, amide, hydroperoxide, polymethylamine, methyl group, etc. Use it.

  Here, in order to make the structure of the movement blocking film 40 that can withstand the severe environment of the mounting temperature (−40 to 150 ° C.) in the vehicle, a material having a structure as shown in FIG. 16 is selected. In FIG. 16, the functional group for binding to the heat radiating member 30 side and the functional group for binding to the housing metal side include a methyl group, an amino group, a sulfo group, a hydroxyl group, and a carboxyl group. Moreover, it has a benzene ring and a hydrocarbon chain between these both functional groups. Here, in the low temperature direction, the hydrocarbon chain is lengthened so as not to be cured at low temperature, and in the high temperature direction, the benzene ring is sandwiched between hydrocarbon chains (molecular long chains) to decompose at high temperature. Do not do it. Thus, when a material having a benzene ring or a hydrocarbon long chain is used as the movement blocking film 40, the high temperature material characteristics can be improved by the benzene ring, and the low temperature material characteristics can be improved by the hydrocarbon long chain. Can do. Thereby, in the vehicle-mounted electronic control device, it is possible to form a film that prevents movement suitable for the mounting environment.

  Examples of the material having the benzene ring or hydrocarbon long chain (structure of the movement blocking film 40) include, for example, polymethyl polybenzene alcohol, polymethyl polybenzene amine, polymethyl polybenzene epoxy, polymethyl polybenzene sulfonic acid, polyethyl. Examples thereof include polybenzene alcohol. The materials listed here are basically (i) alcohols or amines having a plurality of methyl groups, or (ii) alcohols or amines having a plurality of benzene rings, or (iii) having a plurality of hydroxyl groups. An alcohol, an amine, or the like, or (iv) an alcohol, an amine, or the like appropriately combined with a plurality of methyl groups, a plurality of benzene rings, and a plurality of hydroxyl groups.

  More specifically, as a material for forming a monomer, there are proline, phenylalanine, antipain, chymostatin, bestatin, kynurenine, tyrosine, methylquinolyl, nullfamethizol, tyramine and the like.

As described above, the present embodiment has the following features.
As shown in FIGS. 3 and 7, a polymer material having fluidity is used as the heat radiating member 30, and the heat radiating member 30 and the housing 1 or the pedestal 50 are provided between the heat radiating member 30 and the housing inner surface or the pedestal surface. And a film 40 that is chemically or electrically coupled to block the movement of the heat dissipation member 30. Therefore, by using a fluid polymer material as the heat radiating member 30, no cracks are generated even when stress is applied. In this case, the heat radiating member 30 or the casing 1 is subjected to shock, vibration load, temperature, and the like. When an external force such as a cycle or gravity is applied, the movement of the heat radiating member 30 is caused by the film 40 that is chemically or electrically coupled to the heat radiating member 30 and the housing 1 or the pedestal 50 to prevent the movement of the heat radiating member 30. Be blocked. As a result, even when an external force such as an impact or vibration is applied, a heat dissipation path via the heat dissipation member 30 can be secured to suppress a decrease in heat dissipation. Therefore, there is no need to provide the housing with a dam-like configuration that physically prevents the heat dissipation member 30 from flowing and moving, and the housing surface (inner surface of the housing) where the heat dissipation member 30 is disposed is not required. It can be in a substantially flat state without needing unevenness.

  In addition, as shown in FIG. 5, the housing 1 (or the surface of the housing 1 (or the pedestal surface) can be provided by disposing a film 40 that prevents movement of the heat dissipation member 30 at a location where the heating element 12 can be disposed. Since the movement prevention film 40 is disposed at various locations on the pedestal), the common housing 1 is provided for the circuit boards 11 having different arrangements of the heating elements 12 for various types of circuit boards (printed boards) 11. Can be used. Thereby, it can be set as the housing | casing 1 which has a structure with the highly efficient heat dissipation, aiming at a significant cost reduction.

  Further, as shown in FIG. 6, the cost is reduced by avoiding disposing the film 40 that prevents the movement of the heat radiating member 30 at a location where heat radiation is not required on the inner surface (or pedestal surface) of the housing. be able to.

The procedure (assembly order) for forming the electronic control device of this embodiment will be briefly described as follows.
First, in FIGS. 1 to 3, the movement preventing film 40 is applied to the inner surface of the housing 1 (the upper surface of the lower case 2). For the movement blocking film 40, it is preferable to use a method capable of controlling the film thickness. As the method, a brush coating method, a dip method, a spray coating method, a spin coating method, or the like is used to form a film on the lower housing side. This film thickness management may be determined by the required heat dissipation characteristic of the heat generated from the heating element, and the higher the required heat dissipation characteristic (amount), the thinner the film formation method may be changed in the above-mentioned order. A heat radiating member 30 is applied thereon. This coating is performed by a normal coating method that does not require film thickness management, such as the movement blocking film 40, because the film thickness of the heat dissipation member is determined by the gap tolerance due to the mounting tolerance on the lower case 2 of the circuit board 11. be able to. Further, the circuit board 11 integrated with the connector 20 is mounted and fixed so that the heat generating element 12 is placed on the heat radiating member 30, and the upper case 3 is put on and fixed to form the electronic control device (housing 1). To do.
(Second Embodiment)
Next, the second embodiment will be described focusing on the differences from the first embodiment.

FIG. 17 shows a heat dissipation structure in the present embodiment that replaces FIG.
In the first embodiment, as shown in FIGS. 3 and 7, the heat radiating member 30 and the housing 1 or the pedestal 50 are chemically or electrically connected between the heat radiating member 30 and the housing inner surface or the pedestal surface. A film 40 that is bonded to prevent the heat dissipation member 30 from moving is disposed. On the other hand, in the present embodiment shown in FIG. 17, the heat dissipation member 30 is prevented from moving by being chemically or electrically coupled to the heat dissipation member 30 and the heat generation element 12 between the heat dissipation member 30 and the heat generation element 12. A film 60 is arranged. This film 60 is the same as the movement blocking film 40 described in the first embodiment. In FIG. 17, the mold resin 12 b and the heat radiating plate 12 d (metal) in the heating element 12 are in contact with the movement blocking film 60.

  In the present embodiment, by using a polymer material having fluidity as the heat radiating member 30, cracks do not occur even when stress is applied. Further, in this case, the heat radiating member 30 or the housing 1 is subjected to shock or vibration. When an external force such as the above is applied, the movement of the heat dissipation member 30 is prevented by the film 60 that is chemically or electrically coupled to the heat dissipation member 30 and the heat generating element 21 to prevent the heat dissipation member 30 from moving. As a result, even when an external force such as an impact or vibration is applied, a heat dissipation path via the heat dissipation member 30 can be secured to suppress a decrease in heat dissipation.

  In FIG. 17, the movement prevention film 60 is disposed between the heat dissipation member 30 and the heat generating element 12. However, as illustrated in FIG. 18, the movement prevention film 60 may be disposed between the heat dissipation member 30 and the circuit board 11. Good. That is, as shown in FIG. 18 instead of FIG. 4, the movement of the heat radiating member 30 is prevented by chemically or electrically coupling the heat radiating member 30 and the circuit board 11 between the heat radiating member 30 and the circuit board 11. A film 60 is disposed. The effect in this case is the same as that of FIG. In FIG. 18, the conductor pattern 11b (metal) on the circuit board 11 and the movement prevention film 60 are in contact with each other. However, the insulating layer (resin) of the circuit board 11 and the movement prevention film 60 are not provided with the conductor pattern 11b. You may make it contact.

Also in this case (FIGS. 17 and 18), the movement blocking film 60 has a higher electrical or chemical bonding force with the heat generating element 12 (or the circuit board 11) than the heat radiating member 30, and Since the coupling force is also high, the movement of the heat radiating member 30 is prevented as in the first embodiment.
(Third embodiment)
Next, the third embodiment will be described focusing on the differences from the first and second embodiments.

FIG. 19 shows a heat dissipation structure in the present embodiment.
In the present embodiment, the configuration in FIG. 17 (configuration in which the movement blocking film 60 is disposed) and the configuration in FIG. 3 (configuration in which the movement blocking film 40 is disposed) are combined. That is, in FIG. 19, the movement prevention film 40 is disposed between the heat dissipation member 30 and the inner surface (or pedestal surface) of the housing, and the movement prevention film 60 is disposed between the heat dissipation member 30 and the heating element 12. Yes. By doing in this way, the operation effect by having arrange | positioned the movement prevention film | membrane 40 (operation effect demonstrated in 1st Embodiment), and the operation effect by having arrange | positioned the movement prevention film 60 (2nd implementation) As a result, the movement of the heat dissipation member 30 can be more reliably prevented.

  Specifically, by using a fluid polymer material as the heat radiating member 30, cracks do not occur even when stress is applied. In this case, an external force such as an impact or vibration is applied to the heat radiating member 30 or the housing 1. Is added, the movement blocking film 40 blocks the movement of the heat dissipation member 30 and the movement blocking film 60 blocks the movement of the heat dissipation member 30. As a result, even when an external force such as an impact or vibration is applied, a heat dissipation path via the heat dissipation member 30 can be secured to suppress a decrease in heat dissipation.

  18 may be combined with the configuration of FIG. 18 (configuration in which the movement blocking film 60 is disposed) and the configuration in FIG. 4 (configuration in which the movement blocking film 40 is disposed). In FIG. 20, a movement blocking film 40 is disposed between the heat radiation member 30 and the inner surface (or pedestal surface) of the housing, and a movement blocking film 60 is disposed between the heat radiation member 30 and the circuit board 11. Also by doing in this way, the operational effect (the operational effect described in the first embodiment) by arranging the movement blocking film 40 and the operational effect (the second implementation) by arranging the movement blocking film 60 are provided. As a result, the movement of the heat radiating member 30 can be more reliably prevented.

The exploded view of the electronic control unit in a 1st embodiment. The perspective view of an electronic controller. The heat dissipation structure figure of the heat generating element mounted in the circuit board. The heat dissipation structure figure of the heat generating element mounted in the circuit board. The top view of a lower case. The top view of a lower case. The heat dissipation structure figure of the heat generating element mounted in the circuit board. The heat dissipation structure figure of the heat generating element mounted in the circuit board. (A)-(d) is explanatory drawing for demonstrating the chemical bond between a thermal radiation member and a movement prevention film. (A)-(d) is explanatory drawing for demonstrating the chemical bond between a thermal radiation member and a movement prevention film. (A)-(d) is explanatory drawing for demonstrating the electrical coupling between a heat radiating member and a movement prevention film. (A)-(d) is explanatory drawing for demonstrating the electrical coupling between a heat radiating member and a movement prevention film. (A)-(c) is explanatory drawing for demonstrating the chemical bond between a movement prevention film | membrane and a housing | casing. (A), (b) is explanatory drawing for demonstrating the electrical coupling between a movement prevention film | membrane and a housing | casing. The heat dissipation structure figure of the heat generating element mounted in the circuit board. The figure for structure explanation of a movement prevention film. The heat dissipation structure figure of the heat generating element in 2nd Embodiment. The heat dissipation structure figure of a heat generating element. The heat dissipation structure figure of the heat generating element in 3rd Embodiment. The heat dissipation structure figure of a heat generating element. The exploded view of the electronic controller in background art. The heat dissipation structure figure of the heat generating element in background art. The heat dissipation structure figure of the heat generating element in background art.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Housing | casing 10 ... Electronic component, 11 ... Circuit board, 12 ... Heat generating element, 30 ... Heat-radiating member, 40 ... Movement prevention film, 50 ... Base, 60 ... Movement prevention film.

Claims (12)

In the housing (1), the circuit board (11) on which the electronic component (10) including the heating element (12) is mounted is accommodated, and the heating element (12) or the circuit board (11) and the housing A heat-radiating member (30) having thermal conductivity is interposed between the inner surface of (1) or the surface of the base (50) thermally coupled to the housing (1), and the heating element (12) and the housing. In an electronic control device thermally coupled to the body (1),
As the heat radiating member (30), a polymer material having fluidity is used, and the heat radiating member (30) and the housing (1) are disposed between the heat radiating member (30) and the housing inner surface or the pedestal surface. Alternatively, an electronic control device comprising a film (40) that is chemically or electrically coupled to the pedestal (50) and prevents movement of the heat radiating member (30). In the housing (1), the circuit board (11) on which the electronic component (10) including the heating element (12) is mounted is accommodated, and the heating element (12) or the circuit board (11) and the housing A heat-radiating member (30) having thermal conductivity is interposed between the inner surface of (1) or the surface of the base (50) thermally coupled to the housing (1), and the heating element (12) and the housing. In an electronic control device thermally coupled to the body (1),
As the heat radiating member (30), a fluid polymer material is used, and the heat radiating member (30) is interposed between the heat radiating member (30) and the heating element (12) or the circuit board (11). And an electronic control device comprising a film (60) that is chemically or electrically coupled to the heating element (12) or the circuit board (11) to prevent the heat radiating member (30) from moving. . In the housing (1), the circuit board (11) on which the electronic component (10) including the heating element (12) is mounted is accommodated, and the heating element (12) or the circuit board (11) and the housing A heat-radiating member (30) having thermal conductivity is interposed between the inner surface of (1) or the surface of the base (50) thermally coupled to the housing (1), and the heating element (12) and the housing. In an electronic control device thermally coupled to the body (1),
As the heat dissipation member (30), a polymer material having fluidity is used,
The heat radiating member (30) and the housing inner surface or pedestal surface are chemically or electrically coupled to the heat radiating member (30) and the housing (1) or the pedestal (50) to form the heat radiating member ( 30) disposing a membrane (40) that inhibits movement;
Between the heat radiating member (30) and the heat generating element (12) or the circuit board (11), the heat radiating member (30) and the heat generating element (12) or the circuit board (11) are chemically or electrically connected. An electronic control device characterized in that a film (60) is provided which is connected to prevent heat radiating member (30) from moving. The film (40) for preventing the movement of the heat radiating member (30) is disposed on the entire surface of the housing inner surface or pedestal surface where the heat generating element (12) can be disposed. The electronic control device described. 4. The electronic control device according to claim 1, wherein a portion of the inner surface of the housing or the surface of the base that does not require heat dissipation is not disposed on the film that prevents movement of the heat dissipation member. The electronic control device according to claim 1, wherein a silicone resin material is used as the heat radiating member. The electronic control apparatus according to any one of claims 1 to 5, wherein an epoxy resin material is used as the heat dissipation member (30). The electronic control device according to claim 1, wherein a metal material is used as a material of the casing (1) or the base (50). The electronic control device according to claim 8, wherein aluminum is used as the metal material. The electronic control device according to claim 1, wherein a resin is used as a material on at least a surface of the casing (1) or the pedestal (50). 11. The material according to claim 1, wherein a material having a benzene ring or a long hydrocarbon chain is used as the film (40, 60) for preventing movement of the heat radiating member (30). Electronic control device. As the material having the benzene ring or hydrocarbon long chain, any of polymethyl polybenzene alcohol, polymethyl polybenzene amine, polymethyl polybenzene epoxy, polymethyl polybenzene sulfonic acid, and polyethyl polybenzene alcohol is used. The electronic control device according to claim 11.

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