JPH06243919A - Electronic circuit device filled with resin - Google Patents

Abstract

PURPOSE:To prevent resin, with which the inside of a case is filled, from leaking from a fitting part between the case and a connector recessed part without increasing work labor hours by providing a protrusion in a recessed part of the case where a connector is fitted. CONSTITUTION:Protrusions 7 are band-shaped protrusions provided in an edge external surf ace of a recessed part 3 of a case 1, with a section of the protrusion in a semicircular shape, and the protrusion is provided in a band shape so as to surround the periphery of the recessed part 3 of the case 1. Height of the protrusion 7 is set a little higher than width (thickness direction of case side wall) of an insertion groove 5 of a connector 4 and molded simultaneously with the time of plastic molding the case 1. In the case of fitting the connector 14, integrally formed with an electronic circuit board 2, into the recessed part 3 of the case 1, since the protrusion 7 is formed in a semicircular shape with the point end thinned, the protrusion 7 can be relatively easily fitted to the insertion groove 5 while biting in it of the connector 4. Thus by closely mounting the connector 4 to the case 1 without a clearance in a closely mounting part 8, filled resin cm be prevented from leaking.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic circuit device having a structure in which an electronic circuit is housed and a resin is filled and cured.

[0002]

2. Description of the Related Art FIG. 7 is a top view showing a conventional resin-filled electronic circuit device, and FIG. 8 is a front view of FIG. In the figure,
Reference numeral 1 is a case having an upper surface opening, 2 is an electronic circuit board on which electronic components (not shown) are mounted, 3 is a substantially U-shaped recess provided in a side wall of the case 1, 4 is an insertion groove 5 in the recess 3. The connector 6 is fitted into the connector 6, and the terminal 6 connects the connector 4 and the electronic circuit board 2. Although not shown, Case 1
The inside of the is filled with resin and cured. The case 1 and the connector 4 are made of a plastic molded product in terms of weight reduction, insulation, rust prevention, and productivity.

In the conventional structure, in order to facilitate the assembling workability, the electronic parts and the terminals 5 of the connector 4 are inserted into the electronic circuit board 2 and then immersed in a solder bath to complete soldering at once. Then, the connector 4 integrated with the electronic circuit board 2 is fitted into the recess 3 of the case 1, and then the inside of the case 1 is filled with resin and cured to waterproof the electronic circuit. The resin to be filled needs to sufficiently penetrate even a small space between small electronic components. Because
This is because if the space remains, the air in the space expands and contracts due to temperature changes, and there is a risk of sucking in water. Especially in an electronic circuit device used for an automobile or the like, the temperature change is large and water may adhere, and the remaining space reduces the reliability. Therefore, a material having low viscosity and high permeability is selected for the resin. Further, if the clearance between the connector 4 and the recess 3 of the case 1 is zero, fitting is not possible, so a slight clearance a is provided.

[0004]

Since the conventional resin-filled type electronic circuit device is constructed as described above, there is a problem that the resin easily leaks from the gap a between the connector 4 and the recess 3 of the case 1. Therefore, it was necessary to remove the leaked resin. Also, it has been conventionally practiced to apply an adhesive to the gap a so that the resin does not leak, but an extra application operation of the adhesive is required, and the resin cannot be filled until the adhesive is dried. There was a problem such as lengthening.

The present invention has been made to solve the above problems, and an object thereof is to obtain a resin-filled type electronic circuit device capable of preventing resin leakage without increasing the number of working steps.

[0006]

In the resin-filled electronic circuit device according to the present invention, a projection is provided in a recess of a case into which the connector is fitted, and the projection and the case are closely attached to each other. In addition, a wide gap is provided in the fitting portion between the case and the connector.

[0007]

According to the present invention, the protrusion provided on the case allows the connector and the case to be in close contact with each other, thereby preventing resin leakage. Further, the wide gap provided in the fitting portion between the case and the connector can prevent resin leakage due to the capillary phenomenon that propagates along the fitting boundary line between the case and the connector.

[0008]

【Example】

Example 1. An embodiment of the present invention will be described below with reference to FIGS. In the figure, the same or corresponding parts as those of the conventional one are designated by the same reference numerals and the description thereof will be omitted. In the figure,
Reference numeral 7 denotes a strip-shaped projection provided on the outer surface of the edge of the recess 3 of the case 1, and the projection has a semicircular cross section, and is provided in a strip shape so as to surround the periphery of the recess 3 of the case 1. The height of the protrusion 7 is set to be slightly higher than the width of the insertion groove 5 of the connector 4 (the thickness direction of the side wall of the case). This protrusion 7 is the case 1
It is molded at the same time as the plastic molding.

Connector 4 integrated with electronic circuit board 2
When it is fitted into the recess 3 of the case 1, the tip of the projection 7 bites into the insertion groove 5 of the connector 4. As mentioned above, Case 1,
The connector 4 is a plastic molded product, and the projection 7 has a semicircular shape and the tip is thin, so that the projection 7 can be fitted into the insertion groove 5 of the connector 4 relatively easily. As a result, the case 1 and the connector 4 are in close contact with each other at the contact portion 8 without any gap, so that leakage can be prevented even if a low-viscosity resin is filled.

Embodiment 2. Another embodiment of the present invention is shown in FIG.
FIG. 4 will be described. In the figure, the same or corresponding parts as those of the first embodiment are designated by the same reference numerals and the description thereof will be omitted. In the figure, 9 is a point-like protrusion provided on the outer surface of the edge of the recess 3 of the case 1 and has a hemispherical shape. The height of the projection 9 is set to be slightly higher than the width of the insertion groove 5 of the connector 4 as in the first embodiment. Four protrusions 9 are provided. According to this embodiment, there is an effect that the fitting of the connector 4 is easier than that of the first embodiment, the effect of creating the contact portion 8 is the same, and it is possible to prevent the leakage of the resin.

Embodiment 3. A different embodiment of the present invention will be described with reference to FIGS. In the figure, the same or corresponding parts as those in the second embodiment are designated by the same reference numerals and the description thereof will be omitted. In the above-described first and second embodiments, when the amount of resin filled in the case 1 is small, it is an effective method for preventing resin leakage, but the height of the electronic components inside is high and the filling resin is filled in the case 1.
When it is filled up to the full open end, new resin leakage occurs.

That is, the contact portion 8 between the case 1 and the connector 4
Does not leak, but leaks along the tight boundary. It leaks due to the so-called capillary phenomenon. For example, if a concrete wall of a building has a small crack, it is a phenomenon similar to water leaking. In order to prevent such leakage, in the third embodiment, a notch 10 is provided on the upper edge of the recess 3 of the case 1 and a wide gap 11 is formed between the notch 10 and the connector 4. The wide gap portion 11 prevents the capillary phenomenon. That is, when the gap becomes wide, the capillary phenomenon does not occur. In the experiment, the capillary phenomenon could be prevented by providing a gap of about 1 mm.

[0013]

As described above, according to the present invention, by providing the projection on the case, it is possible to prevent the filling resin from leaking without deteriorating the workability and the assembling property.

[Brief description of drawings]

FIG. 1 is a top view showing a first embodiment of the present invention.

FIG. 2 is a front view of FIG.

FIG. 3 is a top view showing a second embodiment of the present invention.

FIG. 4 is a front view of FIG.

FIG. 5 is a top view showing a third embodiment of the present invention.

FIG. 6 is a front view of FIG.

FIG. 7 is a top view showing a conventional example.

8 is a front view of FIG. 7. FIG.

[Explanation of symbols]

 1 Case 2 Electronic Circuit Board 3 Recess 4 Connector 5 Insertion Groove 7 Protrusion 8 Adhesion Part 10 Notch

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[Procedure amendment]

[Submission date] August 5, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0003

[Correction method] Change

[Correction content]

In the conventional structure, in order to facilitate the assembling workability, the electronic components and the terminals 6 of the connector 4 are inserted into the electronic circuit board 2 and then immersed in a solder bath to complete soldering at once. Then, the connector 4 integrated with the electronic circuit board 2 is fitted into the recess 3 of the case 1, and then the inside of the case 1 is filled with resin and cured to waterproof the electronic circuit. The resin to be filled needs to sufficiently penetrate even a small space between small electronic components. Because
This is because if the space remains, the air in the space expands and contracts due to temperature changes, and there is a risk of sucking in water. Especially in an electronic circuit device used for an automobile or the like, the temperature change is large and water may adhere, and the remaining space reduces the reliability. Therefore, a material having low viscosity and high permeability is selected for the resin. Further, if the clearance between the connector 4 and the recess 3 of the case 1 is zero, fitting is not possible, so a slight clearance a is provided.

Claims (3)

[Claims] 1. An electronic circuit board on which electronic parts are mounted, a connector attached to the electronic circuit board, a case having an upper surface opening for accommodating the electronic circuit board, and a connector provided on a side wall of the case for mounting the connector. In a resin-filled type electronic circuit device comprising a recess fitted from above and a resin filled in the case, in a resin-filled type electronic circuit device, which is formed around the connector and fits on an edge of the recess and is thinner than a thickness of the edge. A resin-filled electronic circuit device comprising: an insertion groove having a large width; and a protrusion provided on an outer peripheral surface of the recess so as to abut the insertion groove. 2. The resin-filled electronic circuit device according to claim 1, wherein the protrusions are strip-shaped or dot-shaped protrusions. 3. The resin-filled electronic circuit device according to claim 1, wherein a notch is provided in the recess of the case so that an upper edge of the recess is widened with respect to the insertion groove. .