WO2018074115A1

WO2018074115A1 - Electronic control device

Info

Publication number: WO2018074115A1
Application number: PCT/JP2017/033224
Authority: WO
Inventors: 阿部　純; 孝龍顧
Original assignee: 株式会社ケーヒン
Priority date: 2016-10-17
Filing date: 2017-09-14
Publication date: 2018-04-26
Also published as: JP2018067580A

Abstract

An electronic control device (10) provided with: a storage case (20) for storing a circuit board in a state with a portion of connectors (11L, 11R) protruding; and an encapsulating material (30) encapsulated inside the storage case (20), wherein the storage case (20) is a resin molded part, the inner surface is a flat surface, and on the outer surface, a plurality of depressed recesses (32) are arranged regularly facing the inner surface.

Description

Electronic control unit

The present invention relates to an electronic control device that is mounted on a vehicle, particularly a two-wheeled vehicle, and controls an engine.

Storing the circuit board in the storage case makes it possible to protect the circuit board from water and dust, and keep the circuit board in a healthy state. Electronic control devices including a storage case have been put into practical use in various forms (for example, see Patent Document 1).

The electronic control device according to Patent Document 1 includes a circuit board, an envelope-like storage case for storing the circuit board, and an encapsulating material sealed in the storage case.

The circuit board is inserted from the open part of the storage case.
The encapsulating material is a resin having high fluidity. After the circuit board is inserted into the storage case, the encapsulating material is filled into the storage case from the opening and cured. The hardened encapsulant protects the circuit board from water and dust.

The technique of automatically stopping the engine when the vehicle is stopped and automatically starting the engine when the vehicle starts is called idling stop.
In recent years, circuits have become complicated by adopting an idling stop or by using an LED (light emitting diode) as a lamp. Along with this, the electronic components to be mounted have become larger. As a result, the electronic control device becomes large.
The storage case is heated by the encapsulating material in a fluid state, and the temperature rises. When the encapsulating material is cooled, the temperature of the storage case decreases. When receiving such a temperature change, the storage case may be deformed.
This deformation becomes more prominent as the storage case becomes larger. In particular, the opening-like opening portion is significantly deformed.

Improved rigidity of the storage case is required. As one of the measures for improving rigidity, it has been conventionally known to provide a reinforcing rib (see, for example, Patent Document 2).
The upper case according to Patent Document 2 includes lattice-shaped reinforcing ribs on the inner surface thereof. This reinforcing rib increases the bending rigidity and bending rigidity of the upper case.

However, if there is a reinforcing rib, it becomes difficult to fill the encapsulating material. That is, when there is no reinforcing rib, the encapsulating material in a fluid state smoothly flows along the inner surface of the upper case. On the other hand, when there is a reinforcing rib, the flow of the encapsulated material in a fluid state is disturbed by the reinforcing rib, and filling failure is likely to occur. In particular, it becomes difficult for the encapsulating material to enter the reinforcing ribs (wrinkles), and cavities are easily formed in the portions. As a result, molding defects such as defective filling occur.

While a large electronic control device is required, a storage case capable of improving rigidity while improving the flow of the encapsulating material is required.

JP 2015-47931 A JP 2012-64874 A

An object of the present invention is to provide an electronic control device including a storage case capable of improving rigidity while improving the flow of the encapsulating material.

According to a first aspect of the present invention, there is provided a circuit board on which a connector is mounted and an electronic component is mounted, a storage case that stores the circuit board in a state in which a part of the connector protrudes, and the circuit board is stored. An electronic control device comprising an encapsulating material encapsulated in the storage case in a state of being
The storage case is a resin molded product, the inner surface is a flat surface, and a plurality of recesses that are recessed toward the inner surface are regularly arranged on the outer surface.

In the invention according to claim 2, preferably, the storage case is an injection-molded product, and the concave portion has a pierced portion formed by dividing the resin material injected from the gate.

In the invention according to claim 3, preferably, the storage case includes a front surface from which the connector protrudes, a back surface facing the front surface, left and right side surfaces connecting the back surface and the front surface, and front, back and left and right side surfaces. It has 6 surfaces consisting of a top surface and a bottom surface that are enclosed,
The recess is provided on at least one of the top surface and the bottom surface.

In the invention according to claim 4, it is preferable that the resin material is a glass short fiber mixed with resin.

In the invention according to claim 1, the storage case is a resin molded product, the inner surface is a flat surface, and a plurality of recesses that are recessed toward the inner surface are regularly arranged on the outer surface.
The concave portion is formed by a convex portion provided in the molding die. The flow of the resin material is controlled by convex portions provided on the molding die and regularly arranged. By this control, the resin material can be filled to every corner. In the present invention, since the resin material can be uniformly filled, the rigidity can be increased as compared with the conventional technique in which the flow of the resin material is not controlled.

In addition, since the inner surface of the storage case is a flat surface in the enclosing process performed in a subsequent process, the encapsulating material flows smoothly.
As a result, according to the present invention, there is provided a technique capable of improving the rigidity of the storage case while improving the flow of the encapsulating material.

In the invention according to claim 2, the storage case is an injection-molded product, and the concave portion has a pierced portion formed by dividing the resin material injected from the gate.
The pierced part formed in the concave part is formed by a pierced part provided in the convex part on the molding die side. The flow of the resin material can be more preferably controlled by smoothly dividing the resin material at the edge portion on the convex portion side.

In the invention which concerns on Claim 3, the recessed part is provided in at least one of the upper surface and bottom face of a storage case.
The convex portion may be provided in any of three cases: provided on both the top and bottom surfaces of the storage case, provided only on the top surface of the storage case, and provided only on the bottom surface of the storage case.

When provided on both the top and bottom surfaces, the overall rigidity of the storage case can be increased.
When provided only on the upper surface, the rigidity of the upper surface can be increased, so that deformation of the upper surface can be reduced.
When it is provided only on the bottom surface, the upper surface of the top surface becomes flat and the appearance is enhanced.

In the invention according to claim 4, in the resin material, glass short fibers are mixed with the resin.
Glass short fiber is a reinforcing material. The short fibers extend along the flow of the resin material. Since the orientation of the short fibers is controlled, the rigidity can be further increased.

It is a disassembled perspective view of the electronic controller which concerns on this invention. FIG. 2A is an external view of the electronic control device, FIG. 2A is a view of the top surface, and FIG. 2B is a view of the bottom surface. It is a schematic diagram of the metal mold | die for shaping | molding. It is a perspective view explaining the orientation of the short fiber of glass.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

As shown in FIG. 1, the electronic control device 10 has

connectors

11L and 11R (L is a subscript indicating the left, R is a subscript indicating the right, and so on) and the

electronic component

12, 13 is mounted in the storage case 20, the storage case 20 for storing the circuit board 14 in a state in which a part of the

connectors

11L and 11R protrudes, and the circuit board 14 in the stored state. And an encapsulating material 30. The encapsulating material 30 is drawn as an oval shape for convenience, but is not limited to this shape because it is an indeterminate material. Further, the circuit configured on the circuit board 14 is omitted. The numbers and shapes of the

connectors

11L and 11R and the

electronic components

12 and 13 are not limited to the embodiments.

The circuit board 14 includes, for example, a glass epoxy resin plate 15 with copper foil,

electronic components

12 and 13 mounted on the upper surface of the resin plate 15, and

connectors

11L and 11R attached to one end of the resin plate 15. .

The storage case 20 has an envelope shape and has six surfaces.
The six surfaces include an open front surface 21 through which the

connectors

11L and 11R penetrate, a rear surface 22 facing the front surface 21, left and right side surfaces 23L and 23R connecting the rear surface 22 and the front surface 21, and a front surface 21 and a rear surface 22 The upper surface 24 and the bottom surface 25 are surrounded by the left and right side surfaces 23L and 23R.

Stays

26L and 26R are provided on the left and right side surfaces 23L and 23R, respectively. The electronic control device 10 can be fastened to the vehicle body via the

stays

26L and 26R.

Gate marks 27 and 27 remain on the back surface 22.

Grooves

23a and 23a through which the glass epoxy resin plate 15 can be taken in and out are provided on the inner surfaces of the left and right side surfaces 23L and 23R.

The circuit board 14 is stored in the storage case 20 by inserting the glass epoxy resin plate 15 into the

grooves

23a and 23a.
Next, an encapsulating material 30 called potting resin is encapsulated from the opening-shaped front surface 21. Since the circuit board 14 is surrounded by the encapsulating material 30 after the encapsulation, there is no concern that surrounding water or dust will reach the

electronic components

12 and 13 or the circuit.

FIG. 2 shows the external appearance of the electronic control device 10.
In FIG. 2A, the upper surface 24 of the storage case 20 is mainly shown. The upper surface 24 has a flat upper surface.
In FIG. 2B, the bottom surface 25 of the storage case 20 is mainly shown. The bottom surface 25 has a plurality of (in this example, seven) concave portions 32 regularly arranged on the upper surface.

FIG. 3 is a view showing an example of a molding die.
As shown in FIG. 3A, the molding die 40 includes, for example, a slide die 41, and an upper die 42 and a lower die 43 that are arranged vertically so as to sandwich the slide die 41.
The slide mold 41 corresponds to a core and moves as indicated by an arrow (1).

The slide mold 41, the upper mold 42, and the lower mold 43 constitute a back surface cavity 44, a top surface cavity 45, and a bottom surface cavity 46.
The upper mold 42 moves relative to the lower mold 43 as indicated by an arrow (2).

The lower mold 43 includes a plurality of convex portions 50. The convex portion 50 projects toward the upper mold 42 to about half the thickness of the bottom surface cavity 46. These convex portions 50 are projections for forming the concave portions 32 described with reference to FIG.
In this example, the lower mold 43 has a gate 47. The gate 47 is open to the back cavity 44. The structure of the molding die 40 can be changed as appropriate. For example, the gate 47 can be provided on the upper die 42.

FIG. 3B is a view taken along the line bb in FIG.
As shown in FIG. 3B, the convex portions 50 are regularly arranged. An axis parallel to the back surface 22 is an x axis, and an axis orthogonal to the x axis is a y axis.
In this example, the convex portion 50 is basically a square (square prism) that can draw two diagonal lines. Of the two diagonal lines, squares (quadrangle prisms) are arranged so that one is parallel to the x-axis and the other is parallel to the y-axis.

As viewed from the left and

right gates

47, 47, substantially triangular prism-shaped convex portions 51 L, 51 R are disposed symmetrically, a quadrangular prism-shaped convex portion 52 is disposed at the center in the back, and a substantially triangular prism-shaped convex portion 52 is disposed at the center left and right. Convex portions 53L and 53R are disposed, and substantially triangular prism-shaped convex portions 54L and 54R are disposed in the back (near the front surface 21). Such an arrangement is called a staggered arrangement (a style in which an adjacent convex part is arranged between a convex part and a convex part of a certain row). As described above, the plurality of convex portions 50 are regularly arranged symmetrically as viewed from the gate 47.

Then, at least one of the four corners of the quadrangular prism-shaped convex portion 52 becomes a tip portion (tip portion) 55 that separates the resin material. The substantially triangular prism-shaped convex portions 51L, 51R, 53L, 53R, 54L, and 54R also serve as edge portions (tip portions) 55 at which at least one of the corners divides the resin material.

The resin material injected from the

gates

47 and 47 flows substantially obliquely (obliquely with respect to the x-axis and y-axis) as indicated by the arrow (3), and then the arrows (4), (5), and (6). Divide as follows. These arrows (4), (5), and (6) form an oblique flow. Among them, the flow of the arrows (4) and (5) goes around the convex portion 54L and becomes the flow of the arrows (7) and (7). As a result, an edge on the front 21 side is formed.

When the convex portion 50 is not provided, the resin material injected from the

gates

47 and 47 flows irregularly in a direction in which it easily flows. The irregular flow may cause the packing density of the resin material to vary depending on the part. The portion having a small packing density has a low strength.
On the other hand, in this invention which provided the convex part 50, the flow of the resin material is controlled. Since the flow becomes regular, the packing density of the resin material becomes uniform. By being uniform, the quality of the molded product is improved and the strength is maintained.

After the resin material injected from the gate 47 is cured, excess material is cut off by the gate cutter. In the vicinity of the gate 47, gate marks (FIG. 1, reference numerals 27 and 27) remain on the resin molded product (storage case 20).

Since it is formed by the convex portion 50 and the edge portion 55 in FIG. 3B, the concave portion 32 shown in FIG. 2B has a wedge-shaped portion 33 formed by dividing the resin material. It is formed.
Even if the convex portion 50 in FIG. 3B has another shape, for example, a hexagonal column shape, at least one of the corners of the hexagonal column becomes the piercing portion 55, and the piercing portion 33 is formed in the concave portion 32. Therefore, regardless of the shape of the recess 32, the recess 32 has at least one spatula 33.

In addition to the resin, the resin material may be mixed with glass fiber. Glass fiber exhibits a reinforcing action. Glass fibers include short fibers and long fibers, but short fibers are used.
Since the short glass fiber has a diameter of several μm and a length of several hundred μm and is sufficiently small, it is kneaded with a resin by an injection machine and injected from the nozzle in a state of being mixed with the resin.

FIG. 4 is a diagram for explaining the orientation of the short glass fibers 57 on the bottom surface 25 of the storage case 20.
Although the glass short fiber 57 does not appear on the outer surface, it is shown in an emphasized manner for the sake of simplicity. Further, the glass short fibers 57 are easily entangled and easily beaded, but in FIG. 4, they are shown as straight lines for the sake of simplicity.

As shown in FIG. 4, since the flow of the resin material is not controlled in the bottom portion of the recess 32, the direction of the glass short fibers 57 is irregular. On the other hand, between the adjacent recesses 32, the glass short fibers 57 are oriented obliquely by the flow of arrows (3) to (6) shown in FIG. When oriented obliquely, a sufficiently large rigidity is exhibited against a force along either the x-axis or the y-axis. As a result, the strength of the bottom surface 25 is increased.

In the vicinity of the front surface 21 of the storage case 20, the glass short fibers 57 are oriented along the x-axis by the arrows (7) and (7) shown in FIG. This orientation reinforces the opening of the front face 21. When the opening is reinforced, the opening is not easily deformed even if the encapsulating material (FIG. 1, reference numeral 30) is filled from the opening in a later step. That is, even when the temperature change until the encapsulating material in a fluid state is cured, the opening is not easily deformed.

In this embodiment, as described with reference to FIGS. 2A and 2B, the recess 32 is not provided on the upper surface 24 of the storage case 20, and the recess 32 is provided on the bottom surface 25 of the storage case 20.
The recess 32 is hidden by the vehicle body mounting surface. Since the upper surface 24 is flat, the appearance is good.

When the electronic control device 10 is stored in the vehicle body cover regardless of whether it is a two-wheeled vehicle or a four-wheeled vehicle, the upper surface of the storage case 20 does not become an external appearance surface.
Therefore, the concave portion 32 may be provided on both the bottom surface 25 and the top surface 24. By providing both, the overall rigidity of the storage case 20 can be increased.
Further, the concave portion 32 may be provided only on the upper surface 24.

In addition, although the flat upper surface 24 is shown in FIG. 2A, the upper surface 24 may have a stepped shape as a whole.
Although the flat bottom surface 25 is shown in FIG. 2B, the bottom surface 25 only needs to have a recess 32, and may have a stepped shape.

Further, the storage case 20 of the present invention may be a container in which the front surface 21 has a wall in addition to the envelope type, and the

connectors

11L and 11R penetrate or protrude from the wall. The storage case 20 may be integrated at the time of injection molding, or the upper half and the lower half may be molded separately, and the upper half may be fastened and integrated with the lower half by heat fusion or screws.

The present invention is suitable for an electronic control device mounted on a vehicle.

DESCRIPTION OF SYMBOLS 10 ... Electronic control apparatus, 11L, 11R ... Connector, 12, 13 ... Electronic component, 14 ... Circuit board, 20 ... Storage case, 21 ... Front, 22 ... Back, 23L, 23R ... Side, 24 ... Top, 25 ... Bottom , 27 ... gate marks, 30 ... encapsulating material, 32 ... concave portions, 33 ... pierced portions, 47 ... gates, 57 ... short glass fibers.

Claims

A circuit board on which an electronic component is mounted while a connector is mounted, a storage case for storing the circuit board in a state where a part of the connector protrudes, and a storage case in which the circuit board is stored in the storage case An electronic control device comprising an encapsulating material to be encapsulated,
The storage case is a resin molded product, and has an inner surface that is a flat surface, and a plurality of recesses that are recessed toward the inner surface are regularly arranged on the outer surface.
The electronic control device according to claim 1, wherein the storage case is an injection-molded product, and the concave portion has a crest-like portion formed by dividing a resin material injected from a gate.
The storage case includes a front surface from which the connector protrudes, a back surface facing the front surface, left and right side surfaces connecting the back surface and the front surface, and a top surface and a bottom surface surrounded by the front surface, the back surface, and the left and right side surfaces. It has six sides
The electronic control device according to claim 1, wherein the concave portion is provided on at least one of the top surface and the bottom surface.
3. The electronic control device according to claim 2, wherein the resin material is a glass short fiber mixed with resin.