JP2002271002A - Protection structure for component mounting board - Google Patents

Abstract

(57) [Problem] To provide a protection structure for a component mounting board capable of reducing the cost and improving the moisture-proof reliability by minimizing a potting area to a necessary minimum. SOLUTION: A plurality of electronic components 27, 28, 51, 52 are provided.
Are mounted on the substrates 21 and 50, and the plurality of electronic components 2 are mounted.
In a protection structure of a component mounting board in which 7, 28, 51, and 52 are covered with predetermined resins M and N to protect them, a plurality of electronic components 27, 28, 51, and 52 are potted with epoxy resin M or the like. Are divided into component groups 51 and 52 to be coated and component groups 27 and 28 coated with an acrylic resin N or the like, and mounted on the substrates 21 and 51, respectively. Further, the substrates 21 and 50 are divided into a coating substrate 21 for coating and a potting substrate 50 for potting.
And was configured separately.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to, for example, laminating a control board on which control parts used in an electronic control unit (ECU) are mounted and a printed board on which electronic parts such as relays are mounted. The present invention relates to a protection structure for a component mounting board which is protected by a resin.

[0002]

2. Description of the Related Art As a protection structure for a component mounting board of this kind, there is one disclosed in Japanese Patent Application Laid-Open No. 10-303230 shown in FIG. As shown in FIG. 21, a resin-coated mounting board 1 having this kind of protection structure includes at least a printed board 2 and a relay block 3 of a board unit Q in which a relay block 3 as an electronic component is mounted on the printed board 2. The printed circuit conductor and the terminal 4 are embedded in a sealing resin material 6 cured in a bag-like body 5 made of a thin resin film set in an injection mold 7 and cured. 6 is removed from the injection mold 7 together with the bag 5 and formed.

[0003]

However, in the above-mentioned conventional resin-coated mounting board 1, since the entire printed board 2 is potted with the sealing resin material 6, the entire cost is high. Further, since separate parts of the bag-like body 5 and the injection mold 7 made of a thin resin film are required for potting, the cost is further increased.

Accordingly, the present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to protect a component mounting board capable of reducing the cost and improving the moisture-proof reliability by minimizing a potting area. The purpose is to provide a structure.

[0005]

According to the first aspect of the present invention, a plurality of electronic components are mounted on a substrate, and the plurality of electronic components are covered with a predetermined resin for protection. The structure is characterized in that the plurality of electronic components are mounted on the board separately in a component group for potting a predetermined resin and a component group for coating a predetermined resin.

In this structure for protecting a component mounting board, a group of components for potting a plurality of electronic components with a predetermined resin is provided.
Since the components are separated from each other and are mounted on the substrate, the area to be potted is minimized, thereby reducing costs and improving moisture-proof reliability.

According to a second aspect of the present invention, there is provided the protection structure for a component mounting board according to the first aspect, wherein the substrate is divided into a coating substrate for performing the coating and a potting substrate for performing the potting. It is characterized by having done.

In this component mounting board protection structure, the board is divided into a coating board for coating and a potting board for potting, so that the area to be coated and the area to be potted are easily distinguished. Only the parts that need to be potted are concentrated on the potting substrate, and the amount of expensive potting material used can be minimized.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is an exploded front view showing an electric junction box integrated with an electronic control unit according to an embodiment of the present invention, FIG. 2 is a front view of the electric junction box, and FIG. 3 is a plan view of the electric junction box. 4 is a plan view of an electronic control unit built in the electric junction box,
FIG. 5 is a front view of the electronic control unit, and FIG.
7 is a cross-sectional view taken along line AA in FIG. 4, FIG. 8 is an enlarged plan view of a portion E in FIG. 6, and FIG.
10 is a sectional view taken along line BB in FIG. 4, FIG. 11 is an enlarged plan view of a portion F in FIG. 6, and FIG. 12 is a sectional view taken along line JJ in FIG. FIG. 13 shows KK in FIG.
14 is an explanatory view of a land portion used in the electronic control unit, FIG. 15 is a perspective view showing a relationship between the land portion and terminals, FIG. 16 is an enlarged plan view of a portion G in FIG. 6,
17 is a sectional view taken along the line PP in FIG. 16, and FIG.
19 is a right side view of the electronic control unit, and FIG. 20 is a perspective view showing a potting and coating state of the electronic control unit.

As shown in FIGS. 1 to 3, the electronic control unit-integrated electric connection box 10 is made of a synthetic resin and has a box-shaped upper case 11 and is fitted to the upper case 11 so as to be able to be locked and detached. Box-shaped main cover 12 made of synthetic resin
A busbar layer 13 disposed on the upper surface side of the main cover 12 and an electronic control unit (ECU) 20 built in between the upper case 11 and the main cover 12 below the busbar layer 13. It is roughly configured. The electric connection box 10 is mainly used for, for example, power distribution of an automobile, and the electronic control unit 20 controls on / off of, for example, an engine, a light, a wiper, and the like of the automobile.

As shown in FIG. 1, the bus bar layer 13 has a plurality of bus bars 15 arranged on an insulating substrate 14, and one end of each bus bar layer 13 is bent upward to form a slit-shaped press-contact portion 15a or the like. ing. Each busbar 15
The pressure contact portions 15a extend to the relay mounting portion 12a and the fuse mounting portion 12b which are integrally formed on the upper surface side of the main cover 12 shown in FIG. The relay mounting portion 12a has a plug-in relay 16 as an electronic component.
However, a fuse 17 as an electronic component is mounted on the fuse mounting portion 12b.

As shown in FIGS. 1, 4, 5, 10, and 19, the electronic control unit 20 includes straight and crank-shaped terminals 25 and 26 and a resistor 27 as an electronic component.
And a main board (substrate) 21 made of a synthetic resin and mounted with a relay 28 and the like, respectively, and screws 39 so as to face the main board 21 via a plurality of cylindrical bosses 31 with a predetermined clearance therebetween. A substantially plate-shaped terminal plate (heat insulation plate) 30 made of synthetic resin and fixed to the lower surface side of the terminal plate 30 with a plurality of projections 41 such as a plurality of hooks fitted into the plurality of recesses 32 of the terminal plate 30. A plate-shaped plate cover 40 made of synthetic resin and disposed above and opposed to a part of the terminal plate 30 (excluding the area of the frame-shaped holding plate 33) with a predetermined clearance therebetween. Are stacked and held at a predetermined distance from the main board 21 via the holding plate 33 of the terminal plate 30;
And a plurality of control components 51 and 5 such as a microcomputer (CPU).
2 and the jumper wire 5
3 and a rectangular control board 50 connected via terminals (not shown).

As shown in FIG. 6 to FIG.
At the time of assembling with the terminal plate 30, the soldering portion 25 a at the lower end of the straight rod-shaped terminal 25 is guided by the terminal plate 30 into the connection hole 21 a of the main board 21. That is, when assembling the main board 21 and the terminal plate 30, the connection of the main board 21 hole 21
a and a terminal plate 3 holding the intermediate portion 25b of the terminal 25
0, the positions of the positioning holes 34a coincide with each other.
Of the terminal 25 in the connection hole 21a of the main board 21 at a position facing the main board 21 with a predetermined clearance therebetween.
5a is guided and inserted.

The soldering portion 25a of the terminal 25 inserted into the connection hole 21a of the main board 21 is
5 is soldered to a land 22 formed on the lower surface of the main board 21 in a state where the main board 5 is vertically erected.
1 is maintained. This soldered portion (solder fillet) is indicated by the symbol H.

Further, a projecting portion (locking portion) 25c locked in the positioning hole 34a of the terminal plate 30 is formed integrally with the intermediate portion 25b of the terminal 25 so as to protrude annularly. Further, the positioning holes 34 of the terminal plate 30
A is provided in two rows at the center of the terminal press-fitting portion 34 projecting in a block shape on the upper surface side of the terminal plate 30. The terminal press-fit portion 34 protrudes upward from the opening 42 of the plate cover 40, and the terminal press-fit portion 34
The upper end 25d of the more exposed terminal 25 is the main cover 12
Of the connector mounting portion 12c. This terminal 2
5 has an external connector 18 as an electric component
Are fitted.

The projection 25c of the terminal 25 is locked at a predetermined position in the positioning hole 34a of the terminal plate 30 by press-fitting, and this locking state is not sufficiently separated even by mechanical stress due to attachment and detachment of the external connector 18. It has become.

As shown in FIGS. 4 and 10 to 13, an L-shaped crank, a wide, large-current terminal 26 is provided at its upper end (one end) side as a slit blade-shaped pressure contact portion 26a. Heating components such as a plug-in relay 16 and a fuse 17 and an external connector 18 are freely connectable. A pair of forked soldering portions 26b, 26b on the lower end (the other end) side of the terminal 26 are vertically inserted into the connection holes 21b of the main board 21 so as to be inserted into the lower surface of the main board 21. The main board 21 is held by soldering to the formed land portion 23. This soldered portion (solder fillet) is indicated by the symbol H.

As shown in FIG. 11, a wide flat portion 26d is formed in the middle portion 26c of the terminal 26 so as to be parallel to the main substrate 21. The flat portion 26d is The terminal plate 30 can be freely contacted with the terminal pressing portion 35 of the terminal plate 30 disposed at a position facing the terminal plate 21 with a predetermined clearance therebetween. Terminal 2
The wide flat portion 26d of 6 is capable of abutting on a terminal pressing portion 43 provided on a resin plate cover 40 covering the terminal plate 30 with a predetermined clearance from the terminal plate 30. That is, the terminal holding portions 35 of the terminal plate 30 and the terminal holding portions 4 of the plate cover 40 are provided.
3, the wide flat portion 26d of the terminal 26 is clamped.

The terminal plate 30 and the plate cover 4
In the vicinity of the terminal holding portions 35 and 43, the terminal insertion holes 3 are provided.
6, 44 are formed respectively. The press contact portion 26a of the terminal 26 exposed from the terminal insertion hole 44 of the plate cover 40 projects to the relay mounting portion 12a, the fuse mounting portion 12b, the connector mounting portion 12c and the like of the main cover 12. Further, as shown by oblique lines in FIG. 11, the terminal pressing portion 43 of the plate cover 40 is formed to have a width substantially the same as that of the wide flat portion 26d of the terminal 26. FIG.
As shown in FIG. 5, the terminal holding portion 35 of the terminal plate 30 is also formed wide similarly.

Further, as shown in FIGS. 13 and 15, the soldered portions 26b, 26b at the lower end of the terminal 26 which is cranked in an L-shape are divided into two and subdivided. Further, a pair of soldering portions 26 of the terminals 26 of the main board 21 are provided.
b, 26b, a pair of connection holes 21b, 2
1b are formed. Further, FIGS.
As shown in FIG. 5, a pair of round terminal insertion holes 23a, 23a are formed at positions of the terminals 26 of the land portion 23 facing the pair of soldering portions 26b, 26b, respectively. A pair of constrictions 23b, 2 around the land 23 between the pair of terminal insertion holes 23a, 23a of the land 23.
3b is formed.

As shown in FIGS. 6, 10, 16, and 17, at a predetermined position of the terminal plate 30, a component accommodating portion 37 for accommodating and holding the resistor (heating component) 27 is formed in a concave shape. . The concave component housing portion 37 and the main board 2
1 has a pair of insertion holes 37 for inserting a pair of lead portions 27b, 27b protruding from the component body 27a of the resistor 27.
a, 37a and 21c, 21c are formed respectively.

The lead 27b of the resistor 27 is inserted into each of the concave component housing 37 and each of the insertion holes 37a and 21c of the main board 21 so that the resistance 27 is inserted into the bottom 37b of the concave component housing 37. Each of the lead portions 27b and the land portion 24 formed on the lower surface side of the main board 21 are held by soldering in a state where the component main body 27a is separated. This soldered portion (solder fillet) is indicated by the symbol H. In addition, the component housing 37 of the plate cover 40
An opening 45 having the same shape as the size of the component accommodating portion 37 is formed at a position opposed to.

As shown in FIG. 5 to FIG. 7, FIG. 18, and FIG. 19, heat generating components such as a resistor 27 and a relay 28 are mounted via a frame-shaped holding plate 33 integrally formed on the right side of the terminal plate 30. The main board 21 and the control board 50 on which the control components 51 and 52 such as a microcomputer (CPU) are mounted are held and laminated at a predetermined distance. That is, on the ceiling side of the holding plate 33, a heat blocking plate 38 is provided with a pair of side wall portions 33 of the holding plate 33.
a, 33a are integrally formed at the upper end. This heat shield plate 3
An air layer S is formed between the heat shield plate 38 and the control board 50 via a plurality of convex portions 38a integrally formed on the upper surface of the substrate 8.

The control board 50 is formed integrally with each of the pair of side walls 33a, 33a of the holding plate 33 and the heat shield plate 38, and has a hook-like shape which is engaged with the plurality of recesses 54 of the control board 50. It is positioned via each hook 33b. The air layer S between the heat insulating plate 38 and the control board 50 is always maintained at a constant value via the convex portion 38a of the heat insulating plate 38.

Further, as shown in FIGS. 18 and 20, the main substrate 21 is a coating substrate for coating, and a resistor 27 mounted on the main substrate 21 is provided.
And the relay 28 are made of a coating material N such as an acrylic resin.
Is a group of components that apply That is, the main board 21
Lead 27b of at least resistor 27 soldered to
The coating material N such as an acrylic resin is coated on both the front and back surfaces of the main board 21 so as to cover the terminals 28b of the relay 28, respectively.

As shown in FIGS. 18 and 20, the control board 50 is a potting board for performing potting.
Reference numeral 52 denotes a component group for potting a potting material M such as a silicone resin, a urethane resin, or an epoxy resin. That is, a frame-like surrounding plate 55 made of synthetic resin is attached to the holding plate 33 or the like so as to surround the control board 50 and the control components 51 and 52 soldered to the control board 50, respectively. The potting material M such as epoxy resin or the like melted therein is injected and cured so that the potting material M is potted on the control board 50 and the control components 51 and 52.

According to the electronic control unit-integrated electric junction box 10 of the above embodiment, as shown in FIG. 18, the main board 21 for coating and the control board 50 for potting are divided into two parts. Since only the control components 51 and 52 to be potted are collected and soldered, and the other electronic components such as the resistor 27 and the relay 28 are soldered to the main board 21, the region to be coated and the region to be potted can be easily distinguished. In addition, it is possible to reduce the cost and improve the moisture-proof reliability by minimizing the area to be potted.

In particular, the expensive potting material M is applied only to the control substrate 50 and the main substrate 21 is coated, so that only the control components 51 and 52 that require potting are selectively applied to the control substrate 50. The amount of potting material M that is aggregated and costly can be reduced to a necessary minimum as compared with the related art. As a result, electric leakage due to dew condensation, water droplets and the like can be reliably prevented, and sufficient moisture-proof reliability and cost reduction can be further achieved.

According to the above embodiment, two substrates, a coating substrate and a potting substrate, are used.
It is a matter of course that the above-described embodiment can be applied even if one side of one substrate is divided for coating and the other is divided for potting.

[0031]

As described above, according to the first aspect of the present invention, a plurality of electronic components are divided into a component group for potting a predetermined resin and a component group for coating a predetermined resin on a substrate. , The area to be potted can be minimized to reduce costs and improve moisture-proof reliability.

According to the second aspect of the present invention, since the substrate is divided into the coating substrate for coating and the potting substrate for potting, the region to be coated and the region to be potted can be easily distinguished. It is possible to consolidate only a group of components requiring potting on a potting substrate, thereby minimizing the amount of expensive potting material used.

[Brief description of the drawings]

FIG. 1 is an exploded front view showing an electric control box integrated with an electronic control unit according to an embodiment of the present invention.

FIG. 2 is a front view of the electric junction box.

FIG. 3 is a plan view of the electric junction box.

FIG. 4 is a plan view of an electronic control unit built in the electric connection box.

FIG. 5 is a front view of the electronic control unit.

FIG. 6 is a sectional view taken along line DD in FIG. 5;

FIG. 7 is a sectional view taken along line AA in FIG.

FIG. 8 is an enlarged plan view of a portion E in FIG. 6;

FIG. 9 is a sectional view taken along line HH in FIG. 8;

FIG. 10 is a sectional view taken along the line BB in FIG. 4;

FIG. 11 is an enlarged plan view of a portion F in FIG. 6;

FIG. 12 is a sectional view taken along the line JJ in FIG. 11;

13 is a sectional view taken along the line KK in FIG.

FIG. 14 is an explanatory diagram of a land used in the electronic control unit.

FIG. 15 is a perspective view showing a relationship between the land and the terminal.

FIG. 16 is an enlarged plan view of a portion G in FIG. 6;

FIG. 17 is a sectional view taken along the line PP in FIG. 16;

FIG. 18 is a sectional view taken along line CC in FIG. 4;

19 is a right side view of the electronic control unit.

FIG. 20 is a perspective view showing a potting and coating state of the electronic control unit.

FIG. 21 is a cross-sectional view showing a conventional resin-coated mounting board.

[Explanation of symbols]

 Reference Signs List 21 main board (coating board) 27 resistor (electronic component) 28 relay (electronic component) 27, 28 component group to be coated 50 control board (potting substrate) 51, 52 control component (potting component group) M potting material N Coating material

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Yayoi Maki 206-1 Nunobikihara, Haibara-cho, Haibara-gun, Shizuoka Prefecture F-term (reference) in Yazaki Parts Co., Ltd. 5E314 AA24 AA32 AA33 BB02 BB11 BB13 CC01 CC20 DD06 FF01 FF21 GG01 GG26

Claims (2)

[Claims] 1. A component mounting board protection structure in which a plurality of electronic components are mounted on a board, and the plurality of electronic components are covered with a predetermined resin to protect the plurality of electronic components. A component group for potting the resin and a component group for coating a predetermined resin, and mounted on the substrate, respectively. 2. The protection structure for a component mounting board according to claim 1, wherein the board is divided into a coating board for performing the coating and a potting board for performing the potting. Protection structure for component mounting boards.