JP7163022B2 - electronic controller - Google Patents

Description

TECHNICAL FIELD The present invention relates to an improved technique for an electronic control device having heat-generating electronic components.

Some electronic control devices include exothermic electronic components that generate heat. Such electronic control devices are often mounted on vehicles such as automobiles, and are required to have good heat dissipation. In response to this, a technique for an electronic control device that considers heat dissipation has been proposed (for example, Patent Document 1).

In the electronic control device known from Patent Literature 1, a substrate on which heat-generating electronic components are mounted is housed in a housing. This housing consists of a case made of a metal material and a cover that closes the opening of the case. A large number of radiating fins and a plurality of fixing mounting bosses are integrally formed on the outer surface of the case.

However, the plurality of fixing mounting bosses protrude laterally from the side surfaces of the case. Accordingly, the electronic control unit has to be relatively large. In order to miniaturize the electronic control device, it is conceivable to change the position and size of the fixing mounting boss with respect to the case. However, changing the heat dissipation structure of the electronic control unit for that purpose is not a good idea because it affects the heat dissipation performance.

JP 2009-246170 A

SUMMARY OF THE INVENTION It is an object of the present invention to provide a technology capable of reducing the size of an electronic control device without changing the heat dissipation structure of the electronic control device for fixing mounting bosses.

An electronic control device according to the first aspect of the invention comprises a housing comprising a case and a cover for closing an opening of the case, a printed circuit board housed in the housing, and exothermic electronic components mounted on the printed circuit board. including. Either one of the case and the cover is a metal component and has a plurality of fixing mounting bosses. A region in which the heat-generating electronic component is arranged in the printed circuit board is referred to as a heat-generating electronic component arrangement region. The surface of the metal part opposite to the printed circuit board is referred to as the opposite surface. A projected area of the opposite surface is a projected area of the heat-generating electronic component arrangement area. In order to shorten the distance from the heat-generating electronic component to the mounting surface of the plurality of fixing mounting bosses, the plurality of fixing mounting bosses are positioned at the end of the opposite surface and in the vicinity of the projected area. and has heat radiation fins formed on the opposite surface of the metal part, the heat radiation fins being positioned in the projection area and at least a portion of the plurality of fixing mounting bosses. and integrally formed . A plurality of recesses are formed at the end of the opposite surface of the metal part. The plurality of recesses are formed by a first bottom plate located in the center of the metal part, and second and third bottom plates continuously located on both edges of the first bottom plate and having steps. It is The plurality of fixing mounting bosses are positioned in the plurality of recesses and extend from the edge of the first bottom plate to the edge of the second bottom plate, or from the edge of the first bottom plate to the edge of the third bottom plate. and each of which is formed with a lateral screw hole .

In the invention according to claim 1, a plurality of Collecting mounting bosses for fixing. In other words, a plurality of fixing mounting bosses are brought to the inside of the metal part. Therefore, when the housing is viewed from the board surface of the printed circuit board, the plurality of fixing mounting bosses do not protrude outward from the side surfaces of the metal parts. Therefore, it is possible to reduce the size of the electronic control device. Moreover, the fixing mounting boss does not affect the heat dissipation structure of the heat-generating electronic component. Therefore, the size of the electronic control device can be reduced without changing the heat dissipation structure of the electronic control device for the fixing mounting boss.

Furthermore, the plurality of fixing attachment bosses are attached to a mating member such as a vehicle body. Since the plurality of fixing mounting bosses are gathered in the vicinity of the projection area, the distance from the heat-generating electronic component to the mounting surface of the plurality of fixing mounting bosses can be shortened. As a result, thermal resistance between the heat-generating electronic component and the mounting surfaces of the plurality of fixing mounting bosses can be reduced. Therefore, the heat dissipation of the housing can be enhanced.

Furthermore, the plurality of fixing mounting bosses do not protrude outward from the side surfaces of the metal component. It is not necessary to reduce the size of the metal parts themselves in order to reduce the size of the electronic control unit. Therefore, it is not necessary to reduce the size of the printed circuit board housed in the housing. A sufficient mounting area of the printed circuit board can be secured.

Furthermore, by gathering a plurality of fixing mounting bosses in the vicinity of the projection area, the distance between each fixing mounting boss can be reduced to a more appropriate size in consideration of vibration resistance.
Furthermore, in the invention according to claim 1, the heat radiation fins formed on the opposite surface of the metal part are located in the projection area. The heat generated by the heat-generating electronic component can be dissipated from the projection area by the heat-dissipating fins. Since the fixing mounting boss is located in the vicinity of the projection area, it does not affect the heat dissipation from the heat dissipation fins.
Furthermore, in the invention according to claim 1, the strength of the heat radiation fins can be increased by integrating the heat radiation fins with the fixing mounting boss.

Furthermore, in the invention according to claim 1 , the portions where the plurality of fixing mounting bosses are arranged are the plurality of recesses formed at the end of the opposite surface of the metal part. Therefore, when viewed from both the board surface direction and the plate thickness direction of the printed circuit board, the plurality of fixing mounting bosses do not protrude outward from the metal component. Therefore, it is possible to further reduce the size of the electronic control device.

1 is a configuration diagram of an electronic control device according to Embodiment 1 of the present invention, where (a) is a perspective view of an exploded configuration, and (b) is a plan view of a configuration where a cover is removed from a case in which a printed circuit board is assembled; . FIG. 2 is a configuration diagram of the case shown in FIG. 1, (a) is a plan view of the case as seen from the opening side, (b) is a perspective view of the case as seen from below, and (c) is the c part of (b). An enlarged view, and (d) is a bottom view of the case. FIG. 2 is a cross-sectional view of a configuration in which a cover is assembled to the case of the electronic control device shown in FIG. 1, and (a) is a cross section along line 3a-3a in FIG. FIG. (b) is a cross-sectional view taken along line 3b-3b of FIG. FIG. 4 is a configuration diagram of an electronic control device according to Examples 2 and 3 of the present invention, where (a) is a bottom view of the case of Example 2, and (b) is a bottom view of the case of Example 3;

A mode for carrying out the present invention will be described below based on the accompanying drawings.

<Example 1>
An electronic control unit 10 according to a first embodiment will be described with reference to FIGS. 1 to 3. FIG. This electronic control device 10 includes a housing 11 , a printed circuit board 61 housed in this housing 11 , and at least one exothermic electronic component 62 mounted on this printed circuit board 61 . Examples of the heat-generating electronic component 62 include power devices, electrolytic capacitors, and resistors.

The housing 11 has a substantially rectangular shape (including a square shape) in plan view, and is composed of a case 20 and a cover 40 that closes an opening 21 of the case 20 . The cover 40 is a generally flat member that can be superimposed on the edge of the opening 21 of the case 20 and detachably attached with a plurality of screws 41 .

At least one of the case 20 and the cover 40 (for example, the case 20) is a metal component, preferably made of a material having high thermal conductivity such as an aluminum alloy. Here, an example in which the case 20 is a metal part will be described, but it is not limited to this. Hereinafter, the case 20 will be referred to as the "metal part 20" as appropriate.

The case 20 is composed of a bottom plate 22 that is substantially rectangular in plan view, and side plates 23 that rise from the periphery of the bottom plate 22 and surround the periphery. The bottom plate 22 is composed of a first bottom plate 24 located in the center of the case 20 and second and third bottom plates 25 and 26 continuously located on both edges of the first bottom plate 24 . In order to improve the heat dissipation of the case 20, it is preferable that all the bottom plates 24 to 26 have the same plate thickness and are small.

The bottom surface 22a of the bottom plate 22 (the surface 22a facing the opening 21) is composed of the bottom surface 24a of the first bottom plate 24, the bottom surface 25a of the second bottom plate 25, and the bottom surface 26a of the third bottom plate . A bottom surface 24 a of the first bottom plate 24 is a flat surface located at the lowest position of the case 20 from the opening 21 . The bottom surface 25 a of the second bottom plate 25 and the bottom surface 26 a of the third bottom plate 26 are flat surfaces positioned higher than the bottom surface 24 a of the first bottom plate 24 . That is, the bottom surface 25a of the second bottom plate 25 and the bottom surface 26a of the third bottom plate 26 are formed in a stepped shape that is higher than the bottom surface 24a of the first bottom plate 24 by one step. Further, the bottom surface 25a of the second bottom plate 25 and the bottom surface 26a of the third bottom plate 26 are set to the same height and parallel to the bottom surface 24a of the first bottom plate 24. As shown in FIG. The edge of the first bottom plate 24 and the edge of the second bottom plate 25 and the edge of the first bottom plate 24 and the edge of the third bottom plate 26 are integrally connected by vertical plates 27 , 27 .

Pedestals 28 and 29 projecting toward the opening 21 are integrally formed on the bottom surface 25a of the second bottom plate 25 and the bottom surface 26a of the third bottom plate 26, respectively. End surfaces 28a and 29a (surfaces 28a and 29a facing the opening 21) of these pedestals 28 and 29 are flat surfaces parallel to the bottom surfaces 24a to 26a of the bottom plates 24 to 26, respectively.

As described above, there are steps between the first bottom plate 24 and the second bottom plate 25 and between the first bottom plate 24 and the third bottom plate 26 . Empty spaces Sp, Sp are formed below the second bottom plate 25 and below the third bottom plate 26 by this step. The empty spaces Sp, Sp are recesses formed at the end of the lower surface 22b of the bottom plate 22 of the case 20 (the surface 22b of the case 20 opposite to the opening 21). Hereinafter, the empty spaces Sp, Sp are referred to as "recesses Sp, Sp" as appropriate. One recess Sp is formed by the lower surface 25 b of the second bottom plate 25 and one vertical plate 27 . The other recess Sp is formed by the lower surface 26 b of the third bottom plate 26 and the other vertical plate 27 .

As shown in FIGS. 2 and 3 , the case 20 has a plurality of fixing mounting bosses 31 and a plurality of heat radiation fins 32 . The plurality of fixing mounting bosses 31 and the plurality of heat radiating fins 32 are positioned in the plurality of recesses Sp, Sp and are formed integrally with the case 20 . As a result, the plurality of fixing mounting bosses 31 and the plurality of heat radiation fins 32 are positioned closer to the inside of the case 20 . The plurality of fixing mounting bosses 31 and the plurality of heat radiation fins 32 do not protrude outward from the case 20 .

Below, the plurality of fixing mounting bosses 31 will be described first, and then the plurality of heat radiation fins 32 will be described.

As shown in FIGS. 2 and 3, the lower surface 22b of the bottom plate 22 of the case 20 consists of the lower surface 24b of the first bottom plate 24, the lower surface 25b of the second bottom plate 25, and the lower surface 26b of the third bottom plate 26. A plurality of fixing mounting bosses 31 are located on the lower surface 22 b of the bottom plate 22 of the case 20 and at the end of the case 20 . More specifically, each of four corners (see FIG. 2) of the lower surface 22b of the bottom plate 22 of the case 20 is integrally formed with one mounting boss 31 for fixing. Specifically, the plurality of fixing mounting bosses 31 are formed integrally with the bottom surface 25b of the second bottom plate 25 and the bottom surface 26b of the third bottom plate 26. As shown in FIG.

A horizontal screw hole 31 a is formed in each of the plurality of fixing mounting bosses 31 . A plurality of fixing mounting bosses 31 can be laterally bolted to a bracket 51 of a mating member 50 (see FIG. 3B) for mounting the electronic control unit 10 .

The plurality of heat radiation fins 32 are located on the lower surface 22b of the bottom plate 22 of the case 20, similar to the fixing mounting bosses 31. As shown in FIG. More specifically, the plurality of heat radiation fins 32 extend downward (opposite to the opening 21 of the case 20) from the lower surface 25b of the second bottom plate 25 and the lower surface 26b of the third bottom plate 26. As shown in FIG. The lower end surfaces (tip surfaces) of all the heat radiation fins 32 are located on the same side or closer to the lower surfaces 25b and 26b of the second and third bottom plates 25 and 26 than the lower surface 24b of the first bottom plate 24. is preferred. This is because the entire case 20 becomes small.

As shown in FIG. 2, a plurality of heat-dissipating fins 32 located on the bottom surface 25b of the second bottom plate 25 are aligned with two fixing mounting bosses 31 located on the bottom surface 25b of the second bottom plate 25. extending in the direction Also, the plurality of heat radiation fins 32 located on the lower surface 26b of the third bottom plate 26 extend in the arrangement direction of the two fixing mounting bosses 31 located on the lower surface 26b of the third bottom plate 26 as well.

Furthermore, it is more preferable that the plurality of heat radiation fins 32 are formed integrally with at least a portion of the plurality of fixing mounting bosses 31 . By integrating the heat radiation fins 32 with the fixing mounting bosses 31, the strength of the heat radiation fins 32 can be increased.

As shown in FIGS. 1 and 2, the printed circuit board 61 has a shape and size that allows it to be fitted into the inner peripheral surface of the side plate 23 forming the peripheral wall of the case 20 with a slight gap. It has a rectangular shape. The printed circuit board 61 is positioned parallel to the bottom plate 22 and arranged inside the case 20 . As a result, the printed circuit board 61 is housed in the housing 11 .

In addition to heat-generating electronic components 62 , various electronic components 65 that generate less heat (hereinafter referred to as “other electronic components 65 ”) are also mounted on the printed circuit board 61 . One board surface 61a of the printed circuit board 61 facing the cover 40 is hereinafter referred to as a "first board surface 61a", and a surface 61b on the opposite side to the first board surface 61a, that is, The other substrate surface 61b facing the bottom plate 22 is referred to as "second substrate surface 61b".

Specifically, a plurality of heat-generating electronic components 62 and a plurality of other electronic components 65 are mounted on the first substrate surface 61a. Other electronic components 65 are mounted in the central arrangement area A1 in the first substrate surface 61a. The plurality of heat-generating electronic components 62 are mounted in areas A2 and A2 (end area A2 and A2) arranged on both sides of the central arrangement area A1 in the first substrate surface 61a. there is Hereinafter, the areas A2, A2 where the heat-generating electronic components 62 are arranged in the printed circuit board 61 are referred to as "heat-generating electronic-component placement areas A2, A2".

As shown in FIG. 3, when the heat-generating electronic component placement areas A2, A2 of the printed circuit board 61 are projected onto the bottom plate 22 of the case 20, the heat-generating electronic component placement areas A2, A2 are projected onto the end faces of the pedestals 28, 29. 28a, 29a. That is, when viewed from the opening 21 side of the case 20, the heat-generating electronic component placement areas A2, A2 overlap within the ranges of the end surfaces 28a, 29a of the pedestals 28, 29, respectively. In the state where the printed board 61 is attached to the case 20 (the state where it is screwed to the plurality of bosses 63), the second board surface 61b is positioned through layers 66, 66 of heat dissipation grease (heat dissipation grease layers 66, 66). It is in contact with the end faces 28a, 29a of the pedestals 28, 29.

The heat generated by each heat-generating electronic component 62 is transmitted to the second bottom plate 25 and the third bottom plate 26 via the printed circuit board 61 and the heat dissipation grease layers 66, 66, and is radiated from the case 20 to the outside. In particular, the efficiency of heat dissipation to the outside from the plurality of heat dissipation fins 32 of the case 20 is high.

As shown in FIG. 1, a connector 67 is mounted on the second board surface 61b of the printed board 61. As shown in FIG. The insertion port of this connector 67 faces outward from the side surface of the case 20 . Various electronic components (not shown) (excluding heat-generating electronic components) can be mounted on the second substrate surface 61b.

Next, referring to FIG. 2(d) and FIGS. 3(a) and 3(b), the positional relationship between the plurality of fixing mounting bosses 31 and heat-generating electronic component placement areas A2, A2 will be described.

In the state where the printed circuit board 61 is accommodated in the housing 11, the lower surface 22b of the bottom plate 22 of the case 20 can be said to be "the surface 22b of the case 20 opposite to the printed circuit board 61". . Hereinafter, the surface 22b on the opposite side will be referred to as the "opposite surface 22b" as appropriate.

The regions on the opposite surface 22b of the case 20 where the heat-generating electronic component placement regions A2, A2 are projected are referred to as "projection regions Pra, Pra". A plurality of fixing mounting bosses 31 are located at the end of the opposite surface 22b and in the vicinity of the projection areas Pra, Pra (including coincident with the projection areas Pra, Pra).

The above description can be summarized as follows.

As shown in FIG. 2(d) and FIGS. 3(a) and (b), the end of the surface 22b (opposite surface 22b) opposite to the printed circuit board 61 in the metal part 20 (case 20) A plurality of fixing mounting bosses 31 are gathered in the vicinity of the projection areas Pra, which are projection areas A2, A2 of the heat-generating electronic component placement areas A2, A2. In other words, the plurality of fixing mounting bosses 31 are brought closer to the inside of the metal component 20 . Therefore, when viewing the housing 11 from the board surface 61 a of the printed circuit board 61 , the plurality of fixing mounting bosses 31 do not protrude outward from the side surfaces of the metal component 20 . Therefore, the size of the electronic control unit 10 can be reduced. Moreover, the fixing mounting bosses 31 do not affect the heat dissipation structure of the heat-generating electronic component 62 . Therefore, the size of the electronic control device 10 can be reduced without changing the heat dissipation structure of the electronic control device 10 for the plurality of fixing mounting bosses 31 .

Furthermore, the plurality of fixing attachment bosses 31 are attached to a mating member 50 such as a vehicle body (see FIG. 3(b)). Since the plurality of fixing mounting bosses 31 are gathered near the projection areas Pra, the distance from the heat-generating electronic component 62 to the mounting surface of the plurality of fixing mounting bosses 31 can be shortened. As a result, thermal resistance between the heat-generating electronic component 62 and the mounting surfaces of the plurality of fixing mounting bosses 31 can be reduced. Therefore, the heat dissipation of the housing 11 can be enhanced.

Furthermore, the plurality of fixing mounting bosses 31 do not protrude outward from the side surfaces of the metal component 20 . In order to reduce the size of the electronic control unit 10, it is not necessary to reduce the size of the metal part 20 itself. Therefore, it is not necessary to reduce the size of the printed circuit board 61 housed in the housing 11 . A sufficient mounting area for the printed circuit board 61 can be secured.

Furthermore, by gathering a plurality of fixing mounting bosses 31 in the vicinity of the projection areas Pra, the distance between the fixing mounting bosses 31 can be reduced to a more appropriate size in consideration of vibration resistance. can do.

The portions where the plurality of fixing mounting bosses 31 are arranged are the plurality of recesses Sp, Sp formed at the end of the opposite surface 22b of the metal component 20. As shown in FIG. Therefore, the plurality of fixing mounting bosses 31 do not protrude outward from the metal component 20 when viewed from both the direction of the substrate surface 61a of the printed circuit board 61 and the plate thickness direction. Therefore, the size of the electronic control unit 10 can be further reduced.

Further, heat radiation fins 32 formed on the opposite surface 22b of the metal part 20 are located in the projection areas Pra, Pra. The heat generated by the heat-generating electronic component 62 can be dissipated from the projection areas Pra, Pra by the plurality of heat-dissipating fins 32 . Since the plurality of fixing mounting bosses 31 are positioned near the projection areas Pra, there is no influence on the heat dissipation from the plurality of heat dissipation fins 32 .

Furthermore, by integrating the plurality of heat radiation fins 32 with the plurality of fixing mounting bosses 31, the strength of the plurality of heat radiation fins 32 can be increased.

<Example 2>
The electronic control unit 10A of the second embodiment will be described with reference to FIG. 4(a). FIG. 4(a) corresponds to FIG. 2(d). The electronic control unit 10A of the second embodiment replaces the plurality of fixing mounting bosses 31 of the case 20 (metal part 20) of the first embodiment shown in FIGS. 1 to 3 with the case shown in FIG. 20A (metal part 20A) is changed to a plurality of fixing mounting bosses 31A, and the rest of the configuration is the same as that of the first embodiment, so description thereof will be omitted.

A plurality of fixing mounting bosses 31A extend from the edge of the first bottom plate 24 to the edge of the second bottom plate 25 or from the edge of the first bottom plate 24 to the edge of the third bottom plate 26 . The plurality of heat radiation fins 32A are formed integrally with the plurality of fixing mounting bosses 31A. Therefore, the strength of the fixing mounting bosses 31A and the heat radiation fins 32A can be further increased. The screw hole 31Aa provided in the fixing mounting boss 31A may be oriented horizontally or vertically. Other actions and effects are the same as those of the first embodiment, and description thereof is omitted.

<Example 3>
An electronic control unit 10B according to the third embodiment will be described with reference to FIG. 4(b). FIG. 4(b) corresponds to FIG. 4(a). The electronic control unit 10B of Example 3 includes the case 20A (metal part 20A) of Example 2 shown in FIG. 20B), and the rest of the configuration is the same as that of the second embodiment, so description thereof will be omitted.

Specifically, the case 20B of the third embodiment encloses the first bottom plate 24 with the second bottom plate 25 and the third bottom plate 26, and the plurality of fixing mounting bosses 31B are attached to the first bottom plate 24. It is characterized by extending obliquely from the four corners. The multiple heat radiation fins 32B extend between the multiple fixing mounting bosses 31B. It is formed integrally with a plurality of fixing mounting bosses 31B. Therefore, the strength of the case 20B can be further increased. The screw hole 31Ba provided in the fixing mounting boss 31B may be oriented horizontally or vertically. Other actions and effects are the same as those of Examples 1 and 2, and description thereof is omitted.

The presence or absence of the pedestals 28 and 29 provided on the second bottom plate 25 and the third bottom plate 26 is optional. When the pedestals 28 and 29 are eliminated, the heat dissipation grease layer 66 may be directly provided on the second bottom plate 25 and the third bottom plate 26 .
Further, the shape of the plurality of recesses Sp, Sp is arbitrary.

The electronic control units 10, 10A, and 10B of the present invention are suitable for being mounted on vehicles such as automobiles.

DESCRIPTION OF SYMBOLS 10, 10A, 10B... Electronic control unit 11... Housing 20, 20A, 20B... Metal parts (case) 21... Opening, 22... Bottom plate, 22a... Bottom surface, 22b... Opposite surface, 31, 31A, 31B Fixing mounting bosses 32, 32A, 32B Heat radiation fins 40 Cover 61 Printed board 61a First board surface 61b Second board surface 62 Exothermic electronic component A2 Exothermic electronic component placement area, Pra... projection area, Sp... concave portion.

Claims (1)

A housing consisting of a case and a cover that closes an opening of the case, a printed board housed in the housing, and a heat-generating electronic component mounted on the printed board,
In an electronic control device in which one of the case and the cover is a metal part and has a plurality of fixing mounting bosses,
a region in which the heat-generating electronic component is arranged in the printed circuit board is defined as a heat-generating electronic component arrangement region;
The surface of the metal part opposite to the printed circuit board is defined as the opposite surface,
A projection area is the area on the opposite surface where the heat-generating electronic component arrangement area is projected,
In order to shorten the distance from the heat-generating electronic component to the mounting surface of the plurality of fixing mounting bosses, the plurality of fixing mounting bosses are positioned at the end of the opposite surface and in the vicinity of the projected area. and
Having heat radiation fins formed on the opposite surface of the metal part,
The heat radiation fins are positioned in the projection area and formed integrally with at least a portion of the plurality of fixing mounting bosses ,
A plurality of recesses are formed at the end of the opposite surface of the metal part,
The plurality of recesses are formed by a first bottom plate located in the center of the metal part, and second and third bottom plates continuously located on both edges of the first bottom plate and having steps. has been
The plurality of fixing mounting bosses are positioned in the plurality of recesses and extend from the edge of the first bottom plate to the edge of the second bottom plate, or from the edge of the first bottom plate to the edge of the third bottom plate. , each with a laterally oriented screw hole,
An electronic control device characterized by:

Images