JP2012134225A - Substrate attaching structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a substrate attaching structure which can suppress an occurrence of a stress failure such as a break of a lead and solder cracking in an electronic component of a slave substrate when fully potting a resin.SOLUTION: The substrate attaching structure which attach a slave substrate 21 to a master substrate 11 comprises: attaching holes 12 which are provided in the master substrate 11 and attach the slave substrate 21; and attachment parts 22 which are provided on the slave substrate 21 and are attached on the attaching holes 12 in the master substrate 11. The attaching hole 12 of the master substrate 11 has a through-hole plating 14 applied thereon and a land 15 having both sides provided thereon. Strength of connecting the attaching hole 12 of the master substrate 11 with the attachment part 22 of the slave substrate 21 by soldering increases, and accordingly the occurrence of the stress failure such as the break of the lead and the solder cracking can be suppressed during resin full-potting.

Description

  The present invention relates to a board mounting structure.

  Conventionally, as a board mounting structure for attaching a small board to a mother board, clinch is provided on the lead of the electronic component on the child board, and through hole plating is applied to the inner surface of the lead hole of the parent board, and the lead of the electronic component is broken or soldered A module mounting structure has been proposed in which stress in the vertical direction that causes cracking is released by lead clinching, and even if solder cracking occurs, electrical conduction is ensured by through-hole plating (for example, Patent Documents) 1).

JP-A-9-289052 (Claim 1, FIG. 1, FIG. 3, paragraphs 0033 to 0036)

  However, the conventional board mounting structure is still in operation and non-operation when the electronic component is completely covered with resin by resin full potting with urethane resin etc. for the purpose of waterproofing the product, etc. Stress occurs in the resin due to the temperature difference with time and the ambient temperature difference, and this stress is applied to the electronic component, causing stress defects such as lead breakage of the electronic component and solder cracking in the soldered part of the lead There was a risk of occurrence.

  It is an object of the present invention to provide a board mounting structure that can suppress the occurrence of stress defects such as lead breakage of electronic components and solder cracks in a child board during resin full potting.

  The present invention is a board attachment structure for attaching a child board to a mother board, provided in the mother board, for attaching the child board, provided in the child board, and attached to the attachment hole in the mother board. And a through-hole plating and a double-sided land are provided in the mounting hole of the parent substrate.

  In the present invention, a double-sided land is provided on the mounting portion of the subsidiary board.

  In the present invention, the sub board is provided with an electronic component, the electronic component is provided with a lead that is electrically connected to the parent board, and the lead is provided with a clinch.

  According to the present invention, it is possible to increase the connection strength of the mounting portion of the sub-board to the main board, thereby suppressing the occurrence of stress defects such as lead breakage and solder cracking in the electronic components of the sub-board during resin full potting. it can.

The partial cross section front view which shows the board | substrate attachment structure of 1st Embodiment which concerns on this invention FIG. 1 is a view of the parent substrate of FIG. Front view showing a sub-board of the first embodiment The top view which shows the mother board of a 2nd embodiment concerning the present invention B arrow view of FIG. Front view showing a sub board of a second embodiment C arrow view of FIG.

Hereinafter, a substrate mounting structure according to an embodiment of the present invention will be described with reference to the drawings.
(First embodiment)
FIG. 1 shows a board mounting structure 10 of the first embodiment. The board mounting structure 10 is provided in the parent board 11 and is provided in the rectangular board mounting hole 12 for mounting the sub board 21 and the sub board 21 and is inserted into the mounting hole 12 in the parent board 11 and soldered. And a mounting portion 22 to be mounted.

  As shown in FIG. 2, a plurality of mounting holes 12 of the parent substrate 11 are provided, two in this example. These mounting holes 12, 12 are arranged at a predetermined interval from each other. A plurality of circular lead holes 13 are provided between the two mounting holes 12 and 12 in a plan view.

  A through-hole plating 14 is provided on the inner peripheral surface of each mounting hole 12. In addition, lands 15 extending on both the front and back surfaces of the parent substrate 11 are provided in a portion around the opening in each mounting hole 12 so as to be connected to the through-hole plating 14.

  The lead holes 13 are also provided with through-hole plating 16 and lands 17 extending on the front and back surfaces of the parent substrate 11. The land 17 is connected to the through-hole plating 16.

  As shown in FIG. 3, a plurality of, in this case, two, mounting portions 22 of the subsidiary board 21 protrude from the one side edge to the side. A land 23 is provided on the entire surface of at least a portion of each mounting portion 22 inserted into the mounting hole 12 of the parent substrate 11.

  A plurality of electronic components (not shown) are provided between the two attachment portions 22, 22, and the leads 24 project from the sub board 21 in the same direction as the attachment portion 22. Each lead 24 is provided with a clinch 25 positioned in the middle. The clinch 25 can be formed in an arc shape, for example.

  Next, the operation of the board mounting structure 10 will be described. As shown in FIG. 1, when attaching the sub board 21 to the main board 11, the attachment portion 22 of the sub board 21 and the lead 24 are inserted into the attachment hole 12 and the lead hole 13 of the main board 11. Then, the mounting portion 22 is soldered to the through hole plating 14 and the land 15 in the mounting hole 12, and the lead 24 is soldered to the through hole plating 16 and the land 17 in the lead hole 13.

  According to the first embodiment, since the through-hole plating 14 and the lands 15 on both sides are provided in the attachment hole 12 of the parent substrate 11, when the attachment portion 22 of the child substrate 21 is soldered to the parent substrate 11, The connection strength of the soldered part is greatly increased.

  As a result, the stress applied to the child board 21 is concentrated on the attachment portion 22 that has higher connection strength than the lead 24 and does not escape. As a result, the lead 24 is hardly stressed.

For this reason, it is possible to suppress the occurrence of stress defects such as lead breakage of electronic components and solder cracks in the sub-board 21 at the time of resin full potting using urethane resin or the like for the purpose of improving waterproof performance.
In addition, since the attachment part 22 of the sub board | substrate 21 does not require the electrical continuity with respect to the parent board | substrate 11, even if a solder crack generate | occur | produces in the soldering part of the attachment part 22, there is no problem.

  In addition, since the land 23 is provided on the entire surface of the attachment portion 22 of the child substrate 21, the connection strength of the soldering portion of the attachment portion 22 to the parent substrate 11 is further increased. Therefore, it is possible to further suppress the occurrence of stress defects such as lead breakage and solder cracks in the lead 24 and its soldered portion.

  Moreover, since the clinch 25 is provided on the lead 24 of the electronic component on the sub board 21, only the stress exceeding the strength of the mounting portion 22 and the soldering portion of the sub board 21 is released by the clinch 25. As a result, the stress applied to the lead 24 and its soldered portion is very small. Therefore, it is possible to more reliably suppress the occurrence of stress defects such as lead breakage and solder cracking.

(Second Embodiment)
4 and 5 show the parent substrate 31 of the second embodiment.
In addition, the same code | symbol is attached | subjected to the part similar to 1st Embodiment, and detailed description is abbreviate | omitted.
Three mounting holes 32 of the parent substrate 31 are provided at equal intervals. These mounting holes 32 are recessed from one side edge of the parent substrate 31 and opened on one side surface. A through-hole plating 34 is provided on the inner surface of the attachment hole 32, and lands 35 that extend on both the front and back surfaces of the parent substrate 31 are provided in the upper and lower openings of the attachment hole 32.
The lead hole 13 is provided in the vicinity of the mounting hole 32.

  FIG. 6 shows the sub board 41 of the second embodiment. The sub-board 41 is provided with three attachment portions 42 protruding sideways from one side edge at equal intervals. Each attachment portion 42 is formed in a substantially T shape in a side view, and lands 43 are provided over the entire circumference at the lower end portion of the vertical side portion and the horizontal side portion of the T shape.

  The sub-board 41 is provided with a plurality of electronic components (not shown). As shown in FIG. 7, the inverted U-shaped lead 44 in these electronic components is similar to the mounting portion 42. Protrudes sideways. Each lead 44 is provided with a clinch 45.

  According to 2nd Embodiment, there exists an effect | action and effect similar to 1st Embodiment.

DESCRIPTION OF SYMBOLS 10 Board | substrate mounting structure 11 Parent board 12 Mounting hole 13 Lead hole 14 Through-hole plating 15 Land 16 Through-hole plating 17 Land 21 Sub-board 22 Mounting part 23 Land 24 Lead 25 Clinch 31 Parent board 32 Mounting hole 34 Through-hole plating 35 Land 41 Sub board 42 Mounting part 43 Land 44 Lead 45 Clinch

Claims (3)

A board mounting structure for attaching a child board to a parent board,
A mounting hole provided in the parent substrate and for attaching the child substrate;
Provided in the child board, and provided with an attachment portion attached to the attachment hole in the parent board,
A board mounting structure in which through hole plating and double-sided lands are provided in the mounting hole of the parent board. The board mounting structure according to claim 1,
A board mounting structure in which a land is provided in the mounting portion of the subsidiary board. In the board mounting structure according to claim 1 or 2,
A board mounting structure in which an electronic component is provided on the child board, a lead that is electrically connected to the parent board is provided on the electronic component, and a clinch is provided on the lead.

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