JP2012199355A - Electronic controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance heat dissipation performance of a heat generating electronic component mounted on a circuit board.SOLUTION: A heat generating electronic component 2a is mounted on the outer peripheral edge of a circuit board 3 in the close vicinity of the sidewall 10 (second wall part) of a case 5. A heat dissipation material 7 fills between a part of the bottom wall 9 (first wall part) of the case 5 in the close vicinity of the electronic component 2a and the electronic component 2a, and between a part of the sidewall 10 (second wall part) of the case 5 in the close vicinity of the electronic component 2a and the electronic component 2a. Since the heat generated from the electronic component 2a is conducted to the bottom wall 9 (first wall part) of the case 5 and the sidewall 10 (second wall part) of the case 5 through the heat dissipation material 7, heat dissipation performance of the heat generating electronic component 2a can be enhanced when compared with a case where the heat generated from the heat generating electronic component 2a is conducted only to the bottom wall 9 (first wall part) of the case 5.

Description

  The present invention relates to an electronic control device mounted on, for example, an automobile.

  For example, Patent Document 1 discloses a pedestal that comes into close contact with the electronic component from the back side of the wiring substrate to a case where a wiring substrate having electronic components mounted on the surface thereof is attached, and heat dissipation that continues to the pedestal. There is disclosed a technique in which a protrusion is provided and heat generated in the electronic component is diffused from the pedestal to the wide range of the case through the heat dissipation protrusion.

JP 2009-158796 A

  However, in Patent Document 1, since the heat generated in the electronic component is transmitted only to the bottom surface which is the board mounting surface of the case, the heat generation amount of the electronic component is large. In addition, there is a risk that the heat generated in the electronic component cannot be sufficiently dissipated from the electronic component.

  Therefore, in the electronic control device according to the present invention, a housing that houses the circuit board on which the electronic component is mounted includes a pair of upper and lower first wall portions facing the electronic component mounting surface of the circuit board, and the pair of first A circuit board that protrudes from one wall portion of the pair of first wall portions and a second wall portion that is erected on the outer peripheral edge of the wall portion and connects the pair of first wall portions, and the upper end surface of the circuit board. A circuit board support part that supports the heat generating electronic component mounted on the circuit board so as to be close to the second wall part or the circuit board support part of the housing; and A portion of one wall portion close to the heat generating electronic component, and a portion of the second wall portion adjacent to the heat generating electronic component or the circuit board close to the heat generating electronic component. Conducting heat generated by the heat-generating electronic component to the support portion Is characterized by having cormorants and heat dissipating member disposed, the.

  According to the present invention, the heat generated in the heat-generating electronic component is radiated to at least two wall surfaces of the housing, as compared to the case where heat is radiated to one wall surface of the housing. The heat dissipation performance of the heat-generating electronic component can be improved.

The disassembled perspective view which showed typically the schematic structure of the electronic controller which concerns on this invention. The disassembled perspective view which showed typically the schematic structure of the electronic controller which concerns on this invention. 1 is a perspective view of an electronic control device according to the present invention. Sectional drawing along the AA line of FIG. Sectional drawing which shows only the principal part of the cross section along the BB line of FIG. Sectional drawing of the electronic control apparatus of a comparative example. Sectional drawing which shows the principal part of the electronic control apparatus in 2nd Embodiment of this invention. Sectional drawing which shows the principal part of the electronic control apparatus in 2nd Embodiment of this invention.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. 1 to 3 are explanatory views schematically showing a schematic configuration of an electronic control device 1 according to the present invention, FIGS. 1 and 2 are exploded perspective views of the electronic control device 1, and FIG. 2 is a perspective view of the control device 1. FIG.

  The electronic control device 1 is, for example, mounted on an automobile and used for controlling an engine, a brake, etc., and an electronic component 2 such as an exothermic electronic component 2a or various electronic components 2b to 2d is mounted on the electronic component. A plurality of rectangular circuit boards 3 mounted on the front surface 3a and the back surface 3b, and a connector that is attached to the circuit board 3 and electrically connects an electric circuit formed on the circuit board 3 and an external device. 4, a case 5 in which the circuit board 3 is accommodated and fixed, an upper cover 6 that covers the circuit board 3 accommodated in the case 5, and the outer periphery of the back surface 3 b of the circuit board 3 in the electronic component 2. The heat dissipating material 7 that fills the space between the electronic component 2a and the case 5 is generally configured.

  The heat-generating electronic component 2 a is mounted on the outer peripheral edge of the circuit board 3 so as to be close to a side wall 10 (described later) of the case 5. Examples of the electronic component 2 mounted on the circuit board 3 include an IC, an FET (field effect transistor), a MOSFET (oxide film semiconductor field effect transistor), a transistor, a capacitor, a diode, and a resistor.

  The circuit board 3 is made of, for example, glass epoxy resin, and a connector 4 having two connection ports 4a and 4b connected to external connectors (not shown) is attached to the surface 3a of the circuit board 3, respectively. . In the present embodiment, the back surface 3 b side of the circuit board 3 is an attachment surface for the case 5.

  The circuit board 3 has four corners on the outer peripheral edge thereof fixed to a circuit board support portion 11 (described later) of the case 5 by screws 18.

  The case 5 and the cover 6 constitute the housing 8 of the electronic control device 1, and the case 5 has a substantially rectangular dish shape, and the cover 6 has a substantially rectangular dish shape deeper than the case 5. Presents.

  The case 5 is formed of a metal material having excellent heat dissipation such as aluminum or iron, and has a substantially rectangular plate-like bottom wall 9 corresponding to the first wall portion of the housing 8 and a bottom wall 9 (first wall). A side wall 10 corresponding to the second wall portion of the housing 8 erected on the outer peripheral edge of the casing 8, and a circuit board support portion 11 that supports the circuit board 3 with its upper end surface 12.

  A groove 14 that is continuous over the entire circumference of the side wall 10 (second wall portion) is formed at the tip of the side wall 10 (second wall portion). The groove 14 is filled with an adhesive material 15 (see FIG. 4 to be described later), and protrusions 25 (described later) provided on the cover 6 and the tips of engaging protrusions 4 c and 4 c provided on the connector 4. By inserting the side, the case 5 and the cover 6 are bonded and fixed, and are sealed fluid-tight so that foreign matter such as moisture and dust does not enter the housing 8 from the groove 14. An adhesive (not shown) is also applied to a portion where a notch 23 (described later) provided in the cover 6 and a connector 4 abut, and moisture or moisture is applied from the abutting portion into the housing 8. It is sealed fluid-tight so that foreign matter such as dust does not enter.

  The circuit board support portion 11 is a columnar pedestal that protrudes from the four corners of the bottom wall 9 (first wall portion) along the side wall 10 (second wall portion), and the side wall 10 (second wall) over the entire length. Part). In other words, the circuit board support portion 11 is a columnar pedestal that protrudes (protrudes) toward the inside of the case 5 from the side wall 10 (second wall portion).

  The circuit board support portion 11 is positioned in the vertical direction (vertical direction in FIG. 4 described later) of the circuit board 3 in the case 5 by placing the circuit board 3 on the upper end surface 12 thereof.

  The upper end surface 12 of the circuit board support 11 is formed with a screw hole 16 into which a screw 18 for fixing the circuit board 3 to the case 5 is screwed. Then, the upper end surface 12 of the two circuit board support portions 11 of the four circuit board support portions 11 is engaged with a notch hole 3 c formed in the outer peripheral edge of the circuit board 3, and the circuit in the case 5 is Positioning protrusions 17 for positioning the substrate 3 in the horizontal direction are formed.

  The case 5 is integrally provided with a pair of brackets 19 and 19 for mounting the electronic control device 1 to a vehicle body (not shown). In the present embodiment, the electronic control device 1 is attached to the vehicle body by through holes 19a and 19a penetrating vertically in the brackets 19 and 19, respectively.

  The cover 6 is made of a predetermined resin material that is lighter than a metal material, and stands on the substantially rectangular plate-like upper wall 20 corresponding to the first wall portion of the housing 8 and the outer peripheral edge of the upper wall 20. Side wall 21 corresponding to the second wall portion of casing 8 provided, connector housing portion 22 protruding from upper wall 20 in accordance with the outer shape of connector 4, and side wall for facing one end of connector 4 to the outside 21, a notched portion 23 formed by cutting out a part of the wall 21, a flange-like flange portion 24 provided on the distal end side of the side wall 21, and a flange portion 24. 2 wall portion) and a protrusion 25 that engages with the groove 14 at the tip. When the cover 6 is assembled to the case 5 by the cutout portion 23, an opening is formed on one side surface of the housing 8, and one end of the connector 4 can protrude to the outside from this opening. Note that the cover 6 can be formed of a metal material such as aluminum or iron.

  The heat dissipating material 7 converts the heat generated by the plurality of heat-generating electronic components 2 a mounted in series on the back surface 3 b of the circuit board 3 along the outer peripheral edge of the circuit board 3 to the bottom wall 9 of the case 5. It is provided so as to conduct to the (first wall) and the side wall 10 (second wall) of the case 5. The heat dissipating material 7 is a heat dissipating grease based on, for example, silicon, and has an insulating property.

  Specifically, as shown in FIGS. 4 and 5, the heat dissipating material 7 covers the heat-generating electronic component 2 a and is a portion of the bottom wall 9 (first wall portion) of the case 5 that is close to the electronic component 2 a. And the electronic component 2a, and a portion of the side wall 10 (second wall portion) of the case 5 that is close to the electronic component 2a and the electronic component 2a are filled.

  In other words, the heat dissipating material 7 is formed between the electronic component 2a and a portion of the bottom wall 9 (first wall portion) of the case 5 at a distance where heat can be received from the electronic component 2 via the heat dissipating material 7. And the space between the electronic component 2a and the portion of the side wall 10 (second wall portion) of the case 5 that is at a distance where heat can be received from the electronic component 2 via the heat dissipating material 7. Filled. Furthermore, the heat radiating material 7 can be filled with the heat radiating material 7 between the bottom wall 9 (first wall portion) of the case 5 and the electronic component 2, and the heat radiating material 7 can radiate heat from the electronic component 2. The heat dissipation material 7 can be filled between the electronic component 2a and the portion of the electronic component 2a that is at a distance capable of receiving heat via the electronic component 2 and between the side wall 10 (second wall portion) of the case 5 and the electronic component 2. And it is filled so that the part and the said electronic component 2a which are in the distance which can receive the heat radiation from the electronic component 2 via the heat radiating material 7 are filled.

  In addition, when the circuit board 3 is assembled to the case 5, the heat radiating material 7 is preferably liquid or pasty and solidified after assembly.

  In such an electronic control device 1 of the present embodiment, the heat generated in the plurality of heat-generating electronic components 2a is transferred to the two wall surfaces 9, 10 (first wall portion) of the housing 8 via the heat dissipation material 7. Radiated (conducted) to the bottom wall 9 and the second side wall 10), and finally radiated to the outside of the electronic control device 1. Therefore, like the electronic control device 30 of the comparative example shown in FIG. 6, the heat generated in the electronic component 31 a mounted on the back surface 30 b of the circuit board 30 is applied to the bottom wall 34 of the case 33 constituting the housing 32. Compared to the case where heat is radiated only through the heat radiating material 35, the heat dissipation performance of the heat-generating electronic component 2a can be improved in the electronic control device 1 of the present embodiment.

  In other words, in the electronic control device 1 of the present embodiment, even when the heat generation amount of each electronic component 2a is large, the heat generated in the plurality of heat-generating electronic components 2a passes through the heat radiating material 7 to the housing 8. Since the heat is radiated (conducted) to the two wall surfaces 9 and 10 and radiated to the outside of the electronic control device 1, the heat generated in each electronic component 2a is effective without setting a heat sink or the like separately. Heat can be radiated, and it is not necessary to set the configuration of a heat sink or the like separately, so that the entire apparatus can be reduced in size.

  In FIG. 6, reference numerals 31b to 31e denote various electronic components mounted on the surface 30a of the circuit board 30. Further, reference numeral 36 in FIG. 6 denotes a cover that constitutes the casing 32 together with the case 33.

  And in this 1st Embodiment, the thermal radiation material is filled so that the space between the part which adjoins to the exothermic electronic component 2a among the side walls 10 (2nd wall part) of the case 5 and the said electronic component 2a may be filled. 7 is filled, the heat generated in each electronic component 2 a can be efficiently radiated to the side wall 10 (second wall portion) of the case 5.

  In the first embodiment, the heat generated in each electronic component 2a is dissipated to the bottom wall 9 (first wall portion) of the case 5 and the side wall 10 (second wall portion) of the case 5. The heat generated in each electronic component 2a is applied to the circuit board support 11 protruding from the bottom wall 9 (first wall) of the case 5 and the side wall 10 (second wall) of the case 5 to the inside of the case 5. It is also possible to dissipate heat. That is, the heat-generating electronic component 2 a is mounted on the back surface 3 b of the circuit board 3 so as to be close to the circuit board support portion 11, and the electronic component 2 a of the bottom wall 9 (first wall portion) of the case 5 is mounted. You may make it fill with the heat radiating material 7 so that between the adjacent part and the said electronic component 2a and between the circuit board support part 11 of the case 5 and the electronic component 2a may be filled.

  As described above, even if the heat generated in the electronic component 2a is radiated to the bottom wall 9 (first wall portion) of the case 5 and the circuit board support portion 11 via the heat dissipation material 7, the electronic component 2a Compared with the case where the generated heat is radiated only to the bottom wall 9 (first wall portion) of the case 5, the heat radiation performance of the electronic component 2a can be improved.

  In the first embodiment, all circuit board support portions 11 are formed so as to be continuous with the side wall 10 (second wall portion) of the case 5 (integrated with the side wall 10 (second wall portion)). However, it is also possible to set the circuit board support part 11 apart from the side wall 10 (second wall part). Therefore, for example, it is close to the columnar circuit board support portion formed so as to protrude from the approximate center of the bottom wall 9 (first wall portion) of the case 5 so as to support the center portion of the circuit board 3. In addition, an exothermic electronic component 2 a is mounted on the back surface 3 b of the circuit board 3, and a columnar circuit board support portion that is not continuous with the side wall 10 (second wall portion) of the case 5 and the bottom wall 9 of the case 5. Even if the heat dissipating material 7 is arranged so as to conduct heat generated in the electronic component 2a close to the circuit board support portion with respect to the (first wall portion), the heat generated in the electronic component 2a As compared with the case where the heat is conducted only to the bottom wall 9 (first wall portion) of the case 5, the heat dissipation performance of the electronic component 2a can be improved.

  Among the plurality of circuit board support portions 11, there is one in which the upper end surface 12 is set to be a case ground for electrically connecting the case 5 and the circuit board 3. In the case ground, for example, the resist on the back surface 3b of the circuit board 3 is removed from the portion where the upper end surface 12 of the circuit board support portion 11 contacts, and the circuit board 3 and the metal case are removed from the removed resist. 5 is configured by setting a copper conductor pattern (not shown) that electrically connects to 5.

  Therefore, if the heat-generating electronic component 2a is brought close to the circuit board support part 11 where the case ground is set, the electronic component 2a is closer to the circuit board support part 11 where the case ground is not set. The heat radiation performance from the electronic component 2a to the circuit board support portion 11 can be improved by the amount of the copper conductor pattern exposed at the portion where the upper end surface 12 of the circuit board support portion 11 contacts.

  In the first embodiment, a plurality of heat-generating electronic components 2a are mounted in series along the outer peripheral edge of the circuit board 3, and the heat generated by the plurality of heat-generating electronic components 2a is transferred to the case. The bottom wall 9 (first wall) and the side wall 10 (second wall) of the case 5 are conducted to the bottom wall 9 (first wall) of the case 5 and the case 5. The side wall 10 (second wall portion) may be configured to conduct heat generated by one heat-generating electronic component 2a on the circuit board 3.

  If the bottom wall 9 (first wall portion), the side wall 10 (second wall portion), or the circuit board support portion 11 of the case 5 is formed so as to protrude toward the heat-generating electronic component 2a, the electronic Since the component 2a is relatively closer to the inner wall surface of the case 5, it is possible to further improve the heat dissipation performance of the electronic component 2a.

  Hereinafter, although other embodiment of this invention is described, the same code | symbol is attached | subjected about the component same as 1st Embodiment mentioned above, and the overlapping description is abbreviate | omitted.

  FIG. 7 shows a second embodiment of the present invention. The electronic control device 41 in the second embodiment has substantially the same configuration as the electronic control device 1 in the first embodiment described above, but an insulating adhesive is used as the heat dissipating material 7. Therefore, since the circuit board 3 is bonded and fixed to the case 5 by the heat radiating material 7, the screw 18 used for fixing the circuit board 3 to the case 5 in the first embodiment described above is omitted. It has become.

  In such a second embodiment, in addition to the operational effects of the first embodiment described above, the number of parts can be reduced by reducing the number of parts by fixing the screw for fixing the circuit board 3 to the case 5, thereby reducing weight and manufacturing. Cost reduction can be realized.

  FIG. 8 shows a third embodiment of the present invention. The electronic control device 51 according to the third embodiment has substantially the same configuration as the electronic control device 1 according to the first embodiment described above, but is in close contact with both the case 5 and the electronic component 2a instead of the heat dissipation material 7. A heat dissipation sheet 52 is used. The heat radiating sheet 52 is set so as to extend from the bottom wall 9 (first wall portion) of the case 5 to the side wall 10 (second wall portion) of the case 5, and heat generated in the electronic component 2 a is transferred to the case 5. It is possible to conduct to the bottom wall 9 (first wall portion) and the side wall 10 (second wall portion) of the case 5.

  Also in the third embodiment, it is possible to obtain substantially the same operational effects as those of the first embodiment described above.

  The technical ideas of the invention other than the claims that can be understood from the above-described embodiments are listed below.

[Claim a]
A circuit board on which electronic components are mounted;
An electronic control device having a housing for accommodating the circuit board,
An electronic control device, wherein the housing includes a first wall portion of the housing facing an electronic component mounting surface of the circuit board, and a second wall portion erected on an outer peripheral edge of the first wall portion. In
An exothermic electronic component mounted on the outer periphery of the circuit board so as to be close to the second wall of the housing;
An electronic component having heat generation with respect to a portion of the first wall portion adjacent to the heat generating electronic component and a portion of the second wall portion adjacent to the heat generating electronic component. And a heat dissipating material provided to conduct the generated heat.

[Claim b]
The heat dissipating material includes a portion of the first wall portion adjacent to the heat generating electronic component and the heat generating electronic component, and a heat generating electronic component of the second wall portion. The electronic control device according to claim a, wherein the electronic control device is filled so as to fill a space between a portion adjacent to the heat-generating component and the heat-generating electronic component.

[Claim c]
The electronic component according to claim 1, wherein a plurality of heat-generating electronic components are mounted on the circuit board so as to be close to the second wall portion of the housing. Control device.

[Claim d]
The portion of the first wall portion adjacent to the heat-generating electronic component is formed so as to protrude toward the heat-generating electronic component. The electronic control apparatus as described in.

[Claim e]
The portion of the second wall portion adjacent to the heat-generating electronic component is formed so as to protrude toward the heat-generating electronic component. The electronic control apparatus as described in.

[Claim f]
A circuit board on which electronic components are mounted;
An electronic control device having a housing for accommodating the circuit board,
The casing is erected on a pair of upper and lower first wall portions facing an electronic component mounting surface of the circuit board and an outer peripheral edge of the pair of first wall portions, and connects the pair of first wall portions. In an electronic control device comprising: a second wall portion; and a circuit board support portion that protrudes from one wall portion of the pair of first wall portions and supports the circuit board at an upper end surface thereof.
An exothermic electronic component mounted on the circuit board so as to be close to the circuit board support of the housing;
The first wall portion is generated in the heat generating electronic component with respect to the portion close to the heat generating electronic component and the circuit board support portion close to the heat generating electronic component. An electronic control device comprising: a heat dissipating material provided to conduct heat.

[Claim g]
The electronic control device according to claim f, wherein an upper end surface of the circuit board support portion is a case ground that electrically connects the housing and the circuit board.

DESCRIPTION OF SYMBOLS 1 ... Electronic control apparatus 2a ... Electronic component 3 ... Circuit board 3a ... Front surface 3b ... Back surface 5 ... Case 6 ... Cover 7 ... Radiating material 8 ... Housing 9 ... Bottom wall 10 ... Side wall 20 ... Top wall 21 ... Side wall

Claims (4)

A circuit board on which electronic components are mounted;
An electronic control device having a housing for accommodating the circuit board,
The casing is erected on a pair of upper and lower first wall portions facing an electronic component mounting surface of the circuit board and an outer peripheral edge of the pair of first wall portions, and connects the pair of first wall portions. In an electronic control device comprising: a second wall portion; and a circuit board support portion that protrudes from one wall portion of the pair of first wall portions and supports the circuit board at an upper end surface thereof.
An exothermic electronic component mounted on the circuit board so as to be close to the second wall of the casing or the circuit board support;
A portion of the first wall portion adjacent to the heat generating electronic component, and a portion of the second wall portion adjacent to the heat generating electronic component or the heat generating electronic component adjacent to the heat generating electronic component. An electronic control device comprising: a circuit board support portion; and a heat dissipating material provided to conduct heat generated by the heat-generating electronic component.   The heat dissipating material includes a portion of the first wall portion adjacent to the heat generating electronic component and the heat generating electronic component, and a heat generating electronic component of the second wall portion. Between the portion adjacent to the heat-generating electronic component or between the circuit board support portion adjacent to the heat-generating electronic component and the heat-generating electronic component. The electronic control device according to claim 1.   The electronic control device according to claim 2, wherein the heat dissipation material is an adhesive, and the circuit board is fixed to the casing by the heat dissipation material.   The electronic control device according to claim 1, wherein a heat dissipation sheet is used as the heat dissipation material.

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