JP2011096886A - Soldering structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem, wherein when solder piled up on a land is less in flow soldering, there is a possibility of solder cracks being generated thereafter, and when an external force is applied to a lead wire soldered to a land, there is the possibility of peel off the land from a substrate. <P>SOLUTION: In an attitude with an electrode on an end portion of a chip component located on a land, the chip component is directly stuck to a substrate without the interference of the land, so that an amount larger than that of other portions is piled up on a space between the electrode of the chip component and the conductor by flow soldering. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a soldering structure for soldering a conductor to a land attached to a substrate.

  A conductive metal stay such as copper foil is deposited on the surface of the board to form a land, and a through hole is provided in the center of the land, and a conductor such as a lead wire is inserted into the through hole. Soldering the body is done.

  For this soldering, flow type soldering is performed in which solder is placed on the land by moving the land so that the surface on the land side contacts the surface of the molten solder bath. When the solder comes into contact with the land, it adheres to the land and rises due to surface tension. However, if the amount of solder transferred from the solder bath to the land is small, the amount of solder connecting the land and the conductor is small. Then, when a mechanical external force is applied to the conductor or a temperature change is repeatedly applied, the solder breaks and causes a failure.

  Therefore, conventionally, after flow-type soldering has been performed, an operation of adding and adding solder manually has been performed (for example, see Patent Document 1).

JP-A-9-32417 (paragraph 0008)

  In the above-mentioned conventional ones, the lands to be soldered are marked. However, since the work of soldering is performed manually, it takes a lot of work and the solder can be reliably deposited on all desired lands. There is no guarantee that can be done.

  Also, if an external force acts on the conductor connected to the land by solder, there is a risk that the land will peel off from the board in addition to cracking the solder, but if the solder is only deposited on the land, the land will be peeled off. It cannot be resolved.

  Therefore, in view of the above problems, the present invention provides a soldering structure capable of attaching a necessary amount of solder to a land without manually depositing solder, and at the same time preventing peeling of the land. This is the issue.

  In order to solve the above-mentioned problems, the soldering structure according to the present invention is such that a land made of a conductive metal foil is attached to the surface of a substrate, and a conductor inserted through a through-hole formed in the central portion of the land is a land. In the soldering structure for soldering to the chip component, the chip component electrode is bonded directly to the substrate without passing through the land in a posture in which the electrode at the end of the chip component is positioned on the land, and the chip component electrode and It is characterized in that more solder is deposited between the conductor and the other parts.

  Since there is an electrode at the end of the chip component, the solder in the solder bath moves between the land and this electrode. On the other hand, since solder also moves between the land and the conductor, a larger amount of solder is deposited between the electrode of the chip component and the conductor than in other parts where no electrode is provided. It will be. Further, since the chip component is bonded to the substrate, even if an external force is applied to the essential point where the land is peeled off, it is possible to prevent the chip component from pressing the land and peeling off the land.

  Specifically, a plurality of windows are formed on the land so as to surround the through hole so that the substrate is exposed, and an adhesive is injected into the windows to bond the chip components. desirable.

  As is apparent from the above description, the present invention eliminates the need to manually add solder after flow soldering by mounting chip components before flow soldering. Further, the land is prevented from peeling off the substrate.

The figure which shows the structure of one embodiment of this invention Sectional view showing shape of solder on land The figure which shows other embodiment.

  1 and 2, reference numeral 1 denotes an insulating substrate, and a land 2 made of copper foil is formed on at least one side. In the illustrated example, the land 2 is independent, but is appropriately connected to another land.

  The land 2 has a through-hole 22 at the center, and a solder resist is applied outside the circular area indicated by the wavy line 21 so that the solder does not adhere. Further, four window portions 3 were formed so as to be in contact with the wavy line 21 and located outside the wavy line 21. An adhesive is applied to the window portion 3 to bond the chip resistor 4. The window 3 passes through the land 2, and the surface of the substrate 1 is exposed in the window 3. Therefore, the chip resistor 4 is bonded to the substrate 1 by the adhesive 6.

  Electrodes 41 and 42 are formed at both ends of the chip resistor 4, and one electrode 41 is bonded so as to be inside the wavy line 21. A lead wire 5 as a conductor is inserted through the through-hole 22 from the back side.

  In this state, flow soldering is performed by flowing the substrate 1 over the solder bath so that the molten solder contacts the surface to which the lands 2 are attached. Then, the melted solder adheres to the electrode 41 of the chip resistor 4, the area inside the wavy line 21 of the land 2 and the lead wire 5, and soldering is performed.

  As shown in FIG. 2, the soldered state is a state in which the solder 7 is thickly stacked between the electrode 41 and the lead wire 5. Thus, solder cracking is prevented by thickly depositing the solder 7. Further, even if an external force acts on the lead wire 5 and the land 2 tends to peel from the substrate 1, the chip resistor 4 is adhered to the substrate 1, so that the land 2 is separated from the substrate 1 by the adhesive force of the adhesive 6. It is prevented from peeling off.

  In the above embodiment, only one electrode 41 of the chip resistor 4 is used. However, as shown in FIG. 3, a U-shaped notch 23 is formed in the land 2, and an adhesive is formed in the notch 23. The electrodes 41 and 42 on both sides of the chip resistor 4 may be soldered to the land 2 together.

  In the above embodiment, the chip resistor 4 is used. However, other chip parts for chip capacitors may be used, or dummy chip parts having only electrodes at both ends may be separately manufactured and used.

  In addition, this invention is not limited to an above-described form, You may add a various change in the range which does not deviate from the summary of this invention.

DESCRIPTION OF SYMBOLS 1 Board | substrate 2 Land 3 Window part 4 Chip resistance 5 Lead wire 6 Adhesive 7 Solder 22 Through-hole

Claims (2)

  In a soldering structure in which a land made of a conductive metal foil is attached to the surface of a substrate and a conductor inserted through a through hole formed in the center portion of the land is soldered to the land, With the electrode positioned on the land, the chip component is directly bonded to the substrate without going through the land, and by soldering, the solder between the electrode of the chip component and the conductor is more soldered than the other parts. Soldering structure characterized by the fact that it is made to meet the requirements.   2. The chip according to claim 1, wherein a plurality of window portions are formed on the land so as to surround a through-hole so that the substrate is exposed, and an adhesive is injected into the window portions to bond the chip parts. The described soldering structure.

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