JP5500681B2 - Electronic control unit - Google Patents

Description

  The present invention relates to an electronic control device.

  The electronic control device is configured to house a wiring board on which electronic components are mounted in a case, and to protect the wiring board from liquid and dust. This type of case has a case main body having an opening for accommodating the wiring board and a cover attached so as to cover the opening of the case main body, and liquid or the like is placed inside the case between the case main body and the cover. A waterproof structure is formed so as not to enter.

  Here, as a conventional example of the waterproof structure formed in the case, a groove is formed in the case body, a tongue-like protrusion that can be inserted into the groove is provided on the outer edge of the cover, and the tongue-like protrusion is formed by a seal member injected into the groove. (For example, refer patent document 1). The tongue-shaped protrusion is formed by bending the outer edge of the cover outward. When attaching the cover to the case body, the tongue-shaped protrusion is inserted into the groove and engaged, and then the sealing member is inserted into the groove. Inject so that the protrusions are filled and harden.

  Further, as another conventional example of a waterproof structure, a structure in which a cover is attached to a case body after filling a groove in the case body with a liquid sealing material is known (see, for example, Patent Document 2). Near the periphery of the cover, a substantially U-shaped protrusion that protrudes downward is formed. The protrusion is inserted into the liquid seal. Thereby, the outer side of the side part of the protrusion is bonded to the liquid sealing material. In this waterproof structure, the filling amount of the liquid sealing material can be reduced by an amount corresponding to the cross-sectional area of the protrusion portion of the cover.

JP-T-2001-504993 JP 2001-85866 A

However, in the structure in which the groove is filled with the sealing material after the tongue-like protrusion is inserted, the sealing material is exposed to the outside. For this reason, the sealing material is exposed to an external liquid and is easily corroded.
Moreover, in the structure using the substantially U-shaped protrusion, the adhesive strength is ensured by the outer surface of the side part of the protrusion and the sealing material. Here, the outer surface of the side portion of the protrusion is substantially parallel to the side surface of the groove. Therefore, conventionally, the waterproof structure is held by the shear strength. However, in general, since the shear strength is smaller than the tensile strength, in order to obtain sufficient strength, it is necessary to enlarge the contact area between the protrusion and the seal material, or to increase the amount of the seal material. There were problems in terms of cost and cost.
The present invention has been made in view of such circumstances, and an object of the present invention is to provide an electronic control device that is small and has sufficient adhesive strength without being affected by an external liquid or the like.

According to one aspect of the present application, a board on which an electronic component is mounted, a case body that accommodates the board and has an opening, a cover that covers the opening of the case body, and an end of the case body The cover has a flat surface portion that is bonded to the adhesive in the groove portion, and the case main body is located on the inner side of the groove portion. have a projecting portion projecting said above the groove, the outside of the groove has a step portion, it is brought into contact with the flat portion to the step portion, for engaging the flat portion to the step portion An electronic control device characterized in that a protrusion is provided is provided.

According to another aspect of the present invention, the groove is partitioned into a plurality of grooves by a wall, the wall to claim 1, characterized in that it has a height of not more than the lower end of the stepped portion An electronic control device as described is provided.

According to another aspect of the present invention, there is provided the electronic control device according to claim 1 or 2 , wherein the adhesive is an adhesive having fluidity.

  According to the present invention, since the flat portion that contacts the adhesive is provided on the cover, the adhesive strength between the case main body and the cover can be maintained at the tensile strength. Thereby, sufficient adhesive strength can be obtained without increasing the size of the bonded portion.

1 is an exploded perspective view of an electronic control device according to a first embodiment of the present invention. It is sectional drawing along II-II of FIG. 1, Comprising: It is sectional drawing which shows a part of structure of the case main body and cover of an electronic control apparatus. It is sectional drawing which shows the modification which inclined the plane part of the outer edge of a cover to the outward rise. It is sectional drawing which shows a part of structure of the electronic controller which concerns on the 2nd Embodiment of this invention. It is a disassembled perspective view which shows a part of structure of the electronic controller which concerns on the 3rd Embodiment of this invention. It is sectional drawing which shows the state attached to the case main body of FIG. 5 with the cover.

The form for implementing this invention is demonstrated in detail below. In each embodiment, the same constituent elements are denoted by the same reference numerals. In addition, overlapping explanation is omitted.
(First embodiment)
FIG. 1 is an exploded perspective view of the electronic control device according to the present embodiment. The electronic control device 1 has a housing case 2, and a wiring board 3 is arranged in the housing case 2. The storage case 2 has a case main body 4 and a cover 5 attached to the case main body 4 from above. On the wiring board 3, an electronic component 7, a connector 8, and the like are mounted.

  The case main body 4 is manufactured from a metal having high thermal conductivity such as aluminum, and has a concave shape as a whole by forming the side wall portion 11 on the outer peripheral portion. At the bottom of the case body 4, a hole 4 </ b> A through which the connector 8 mounted on the wiring substrate 3 is passed is formed. In addition, a mounting portion 12 for mounting the wiring board 3 is provided inside the side wall portion 11 of the case body 4. The mounting portion 12 is formed with screw holes so that the wiring board 3 can be fixed to the case body 4 with screws 14.

A plurality of screw holes 15 for fixing the cover 5 are formed at the end of the case body 4. For example, one screw hole 15 is formed at each corner of the case body 4.
Further, as shown in FIG. 1 and FIG. 2 which is a side sectional view of the case body 4 and the cover 5, a flange portion 16 protruding outward is provided on the entire periphery of the end portion of the case body 4. The flange portion 16 is formed with a groove portion 21. The groove portion 21 is provided on the entire circumference of the flange portion 16. The groove portion 21 is filled with an adhesive 22.

  The adhesive 22 has fluidity. Examples of such an adhesive 22 include a silicone resin adhesive.

  Further, in the flange portion 16, a projection portion 25 is formed along the groove portion 21 at a position closer to the circuit board 3 than the position where the groove portion 21 is formed, and projects upward from the height of the upper end of the groove portion 21. Further, in the flange portion 16, a step portion 26 is provided along the groove portion 21 on the outer side of the groove portion 21. The height of the upper surface 26 </ b> A of the stepped portion 26 is lower than the height of the upper surface of the protruding portion 25.

  The step portion 26 has a lower surface 26B adjacent to the groove portion 21, an inner side surface 26C rising from the lower surface 26B, and an upper surface 26A continuous with the upper end of the inner side surface 26C.

As shown in FIG. 2, the cover 5 has a side surface portion 32 that is inclined so that the lower side is opened from the central upper surface portion 31, and a flat surface portion 33 is provided on the outer edge of the side surface portion 32. The lower surface 33 </ b> A of the flat surface portion 33 is formed to be parallel to the lower surface 26 </ b> B of the step portion 26 of the case body 4.
Further, the flat surface portion 33 is formed at a position and a size such that the lower surface 33 </ b> A can contact the lower surface 26 </ b> B of the stepped portion 26 of the case body 4 and the adhesive 22 in the groove portion 21. More specifically, the flat surface portion 33 covers the lower surface 26 </ b> B of the step portion 26 and makes contact with more than half of the upper surface of the adhesive 22 when the outer surface of the flat portion 33 abuts against the inner surface 26 </ b> C of the step portion 26. It is formed in length.
The side surface portion 32 of the cover 5 has an inclination angle that does not contact the protruding portion 25 of the case body 4 when the flat surface portion 33 is brought into contact with the step portion 26.

  The flat surface portion 33 may be long enough to form a gap with the inner surface 26C of the step portion 26. Further, the flat portion 33 may have a length that contacts with less than half of the upper surface of the adhesive 22. Furthermore, the side surface portion 32 may have an inclination angle that contacts the protrusion 25 of the case body 4.

Next, a manufacturing process of the electronic control device 1 will be described.
First, the case body 4 is formed by casting or the like. In this casting process, the flange portion 16 and the groove portion 21 of the flange portion 16 are also molded. Moreover, when the cover 5 is manufactured from a metal material, the cover 5 is formed by pressing. In this pressing, the side surface portion 32 and the flat surface portion 33 are also molded at the same time. Furthermore, electronic components are mounted on the circuit board 3.
Thereafter, the circuit board 3 is fixed to the case body 4 with screws 14. Thereby, a part of the connector 8 mounted on the wiring board 3 protrudes outward from the hole 4 </ b> A of the case body 4. Further, the adhesive 22 is filled in the groove 21. The adhesive 22 is filled up to a height that fills the gap of the groove 21 and the upper surface of the adhesive 22 is substantially flush with the lower surface 26B of the stepped portion 26.

  Next, the cover 5 is fixed to the case body 4 with screws 35. The cover 5 is attached to the case body 4 from above the case body 4 so as to close the opening of the case body 4. Thereby, as shown in FIG. 2, the flat portion 33 provided on the outer periphery of the cover 5 is disposed so as to cover at least a part of the groove portion 21 and the lower surface 26 </ b> B of the stepped portion 26 from above. Positioning the case body 4 with respect to the case body 4 is facilitated by bringing the flat surface portion 33 into contact with the stepped portion 26.

The flat surface portion 33 of the cover 5 extends over the adhesive 22 to the step portion 26. For this reason, the adhesive 22 in the groove part 21 is not exposed to the outside, and waterproofness is improved.
Further, a narrow gap 37 is formed between the inclined side surface portion 32 of the cover 5 and the protruding portion 25 of the case body 4. Since the groove portion 21 is filled with the fluid adhesive 22, a part of the adhesive 22 in the groove portion 21 is sucked up by the capillary phenomenon generated by the narrow gap 37. As a result, at least a part of the gap 37 is filled with the adhesive 22. At this time, the side surface portion 32 and the protruding portion 25 are not in direct contact with each other.

  Thereafter, when the adhesive 22 is cured, a waterproof structure is formed between the cover 5 and the case body 4. In this waterproof structure, adhesion by the adhesive 22 between the flat portion 33 of the cover 5 and the groove portion 21 of the case body 4 and adhesion by the adhesive 22 between the side surface portion 32 of the cover 5 and the protrusion 25 of the case body 4 are performed. It is formed by. Thereby, the manufacture of the electronic control device 1 is completed.

  Here, the lower surface 33 </ b> A of the flat portion 33 contacts the adhesive 22 in a planar shape. Therefore, when a force is exerted between the flat portion 33 and the adhesive 22 in the direction of the symbol A in FIG. 2, the adhesion between the cover 5 and the adhesive 22 can be held by the tensile strength. In general, the tensile strength is higher than the shear strength.

  Thus, in this electronic control device 1, it becomes possible to form the waterproof structure between the case main body 4 and the cover 5 with a larger adhesive strength due to the tensile strength than in the conventional case. For this reason, sufficient intensity | strength can be ensured for a waterproof structure, without enlarging the plane part 33 of the cover 5 required in order to form a waterproof structure, or increasing the quantity of the adhesive agent 22. FIG.

Further, by providing the protrusion 25 inside the groove 21, the adhesive 22 is drawn between the protrusion 25 and the side surface 32 of the cover 5 due to surface tension. Since the adhesive area between the case body 4 and the cover 5 is increased by curing the adhesive 22 in this state, the adhesive strength between the case body 4 and the cover 5 can be improved.
Furthermore, since the fluid adhesive 22 is used, the discharge pressure when filling the groove 21 with the adhesive 22 can be lowered, and the management of the adhesive is easy.

Here, FIG. 3 shows a modification of the cover.
The cover 5 </ b> A has a side surface portion 32 that is inclined from the upper surface portion 31, and a flat surface portion 41 is integrally provided on the periphery of the side surface portion 32. The flat surface portion 41 is inclined outwardly with respect to the upper surface portion 31 and the lower surface 26B of the step portion 26.

  Since the adhesive 22 filled in the groove portion 21 of the case body 4 has fluidity, the surface thereof may be wavy. In this case, since the flat portion 41 is inclined with respect to the lower surface 26B on the case body 4 side, a narrow gap is formed between the waved surface of the adhesive 26 and the lower surface 41A of the flat portion 41. By the capillary phenomenon generated by the narrow gap, the adhesive 26 is sucked up so as to fill the narrow gap. Thereby, even when there is a gap between the adhesive 26 and the flat portion 41, the gap is filled with the adhesive 22. As a result, the adhesion between the lower surface 41A of the flat portion 41 and the adhesive 22 can be improved.

(Second Embodiment)
A second embodiment of the present invention will be described with reference to the drawings.
As shown in FIG. 4, the electronic control device 1 has a configuration in which a circuit board 3 is accommodated in an accommodation case 2 including a case body 4 and a cover 5. The cover 5 has a flat portion 33 on the outer peripheral portion thereof. The flat portion 33 is formed in parallel with the upper surface portion 31 of the cover 5. A groove portion 21 is formed in the flange portion 16 on the outer periphery of the case body 4, and a protrusion portion 25 is provided inside the groove portion 21, and a step portion 26 is provided outside the groove portion 21.

As shown in FIG. 4, the stepped portion 26 is formed of a lower surface 26B adjacent to the groove portion 21, an inner side surface 26C rising from the lower surface 26B, and an upper surface 26A continuous to the upper end of the lower surface 26B. Further, the step portion 26 has a protrusion 51 formed on the inner side surface 26C. The protrusion 51 is provided inwardly on at least a part of the upper portion of the inner peripheral surface 26 </ b> C of the step portion 26. The height from the lower surface 26 </ b> B to the protrusion 51 is substantially equal to the height of the flat portion 33 of the cover 5.

  When the electronic control device 1 is manufactured, the circuit board 3 is fixed to the case body 4 and the adhesive 22 is injected into the groove portion 21. Thereafter, the cover 5 is attached to the case body 4 from above. At this time, the flat portion 33 of the cover 5 is brought into contact with the adhesive 22 in the groove portion 21 and the lower surface 26 </ b> B of the step portion 26. The front end of the flat surface portion 33 is inserted between the lower surface 26 </ b> B of the stepped portion 26 and the protruding portion 51, engaged with the protruding portion 51, and brought into contact with the inner side surface 26 </ b> C of the stepped portion 26.

  Thereby, the plane part 33 is positioned and attached to the case body 4. When the adhesive 22 is cured in this state, a waterproof structure is formed between the cover 5 and the case body 4. The waterproof structure is realized by adhesion between the flat surface portion 33 of the cover 5 and the groove portion 21 of the case body 4 and adhesion between the side surface portion 32 of the cover 5 and the protruding portion 25 of the case body 4. Thereby, the manufacture of the electronic control device 1 is completed.

The lower surface 33A of the flat portion 33 is in contact with the adhesive 22 in a flat shape. Therefore, when a force is exerted between the flat portion 33 and the adhesive 22 in the direction of the symbol A in FIG. 2, the adhesion between the cover 5 and the adhesive 22 can be held by the tensile strength. In general, the tensile strength is higher than the shear strength.
Further, the adhesive 22 embedded by capillarity between the protruding portion 25 on the case body 4 side and the inclined side surface portion 32 on the cover 5 side also contributes to an increase in the adhesive strength between the case body 4 and the cover 5.

  In the electronic control device 1, the projection 51 is provided on the stepped portion 26, so that the flat portion 33 of the cover 5 is reliably positioned. Since the flat portion 33 and the adhesive 22 can be reliably brought into contact with each other, a waterproof structure by the case body 4 and the cover 5 can be reliably formed. Further, by engaging the flat portion 33 of the cover 5 with the protrusion 51, the flat portion 33 does not float from the lower surface 26 </ b> B of the step portion 26. Thereby, it is possible to prevent external liquid from entering between the flat portion 33 and the step portion 26 to the adhesive 22. Other effects are the same as those of the first embodiment.

(Third embodiment)
A third embodiment of the present invention will be described with reference to the drawings.
As shown in FIG. 5, the electronic control device 1 has a configuration in which a circuit board 3 is housed in a housing case 2 including a case body 4 and a cover 5. The cover 5 has a flat portion 33 on the outer peripheral portion thereof. The flat portion 33 is formed in parallel with the upper surface portion 31 of the cover 5. A groove portion 21 is formed in the flange portion 16 of the case body 4, and a protruding portion 25 is provided inside the groove portion 21, and a step portion 26 is provided outside the groove portion 21.

  Here, the groove part 21 is divided into a first groove part 61 and a second groove part 62 by providing a partition wall part 60. The first groove 61 is a region where the fluid adhesive 22 is filled, and is disposed inside the case body 4. The second groove portion 62 is disposed outside the case body 4, that is, near the step portion 26, and has a smaller volume than the first groove portion 61. More specifically, the second groove 62 has the same depth as the first groove 61 and is narrower than the first groove 61.

  The partition wall portion 60 has the same height as the lower surface 26 </ b> B of the step portion 26. The height of the partition wall 60 may be lower than the lower surface 26B of the stepped portion 26.

When the electronic control device 1 is manufactured, the circuit board 3 is fixed to the case body 4 and the first groove 61 of the groove 21 is filled with a fluid adhesive 22. At this time, the adhesive 22 may be filled in a large amount so as to rise from the first groove 61. On the other hand, the adhesive 22 is not injected into the second groove 62.
The cover 5 is attached to the case body 4 from above, and the lower surface 33A of the flat portion 33 of the cover 5 is brought into contact with the adhesive 22 in the groove portion 21 and the lower surface 26B of the step portion 26. At this time, the front end surface of the flat portion 33 abuts on the inner side surface 26 </ b> C of the step portion 26.

At this time, as shown in FIG. 6, by pressing the flat portion 33 against the groove portion 21, a part of the adhesive 22 flows into the second groove portion 62 beyond the partition wall portion 60. When the adhesive 22 is cured in this state, a waterproof structure is formed between the case body 4 and the cover 5. The waterproof structure is realized by adhesion between the flat surface portion 33 of the cover 5 and the groove portion 21 of the case body 4 and adhesion between the side surface portion 32 of the cover 5 and the protruding portion 25 of the case body 4. Thereby, the manufacture of the electronic control device 1 is completed.
Here, the lower surface 33A of the flat portion 33 is in contact with the adhesive in a flat shape. Therefore, when a force is exerted between the flat portion 33 and the adhesive 22 in the direction of the symbol A in FIG. 2, the adhesion between the cover 5 and the adhesive 22 can be held by the tensile strength. In general, the tensile strength is higher than the shear strength.

  In the electronic control device 1, when the partition wall 60 is provided and the second groove 62 is not filled with the adhesive 22, the amount of the adhesive 22 supplied to the first groove 61 is large. However, the adhesive 22 was prevented from protruding outside between the cover 5 and the flange portion 16. Therefore, in the filling process of the adhesive 22, the protruding of the adhesive 22 can be prevented without strictly controlling the filling amount of the adhesive 22. Thereby, the filling operation | work of the adhesive agent 22 becomes easy. Other effects are the same as those of the first embodiment.

Here, two or more wall portions 60 for partitioning the groove portion 21 may be formed. The volume of the grooves formed outside the first groove 61 by the partition wall 60 is smaller than that of the first groove 61. Further, the depth of the groove formed on the outside may be shallower than that of the first groove 61.
Furthermore, the protrusion 51 shown in FIG. 4 may be provided on the step portion 26 at the step portion 26.

The present invention can be widely applied without being limited to the above-described embodiments.
For example, the case body 4 may be configured without the protrusions 25. In this case, the side surface portion 32 of the cover 5 may be inclined or may not be inclined.
Further, the case body 4 may be provided with the protrusion 25 and may be disposed substantially at right angles to the flat surface portion 33 without inclining the side surface portion 32 of the cover 5. When a narrow gap is formed without causing the protrusion 25 and the side face 32 to contact each other, the adhesive area can be increased by drawing the adhesive 22 into the gap due to a capillary phenomenon.
Further, the cover 5 may be formed of a resin material.

DESCRIPTION OF SYMBOLS 1 Electronic controller 3 Circuit board 4 Case main body 5 Cover 11 Side wall part 21 Groove part 22 Adhesive 25 Protrusion part 26 Step part 26B Lower surface 26C Inner side surface 32 Side surface part 33 Plane part 33A Lower surface 51 Projection part 60 Partition wall part 61 Groove part 62 second groove part

Claims (3)

A board on which electronic components are mounted;
A case body containing the substrate and having an opening;
A cover covering the opening of the case body;
A groove formed at an end of the case body;
An adhesive filled in the groove,
Including
The cover has a flat portion which is adhered to the adhesive in said groove, said case body is inward from the groove, have a protruding portion protruding the above the groove,
An electronic control device comprising a stepped portion on the outside of the groove portion, and a projecting portion that engages the planar portion on the stepped portion while the planar portion is brought into contact with the stepped portion. . The groove is partitioned into a plurality of grooves by a wall, the wall is an electronic control device according to claim 1, characterized in that it has a lower end below the height of the step portion. The adhesive, the electronic control device according to claim 1 or claim 2, characterized in that an adhesive having fluidity.

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