JPH0374894A - Soldering of circuit part - Google Patents

Abstract

PURPOSE:To realize easy operation and highly reliable soldering by restricting a soldering range arbitrarily using a thermal contracting tube during soldering package of a circuit part to a printed substrate and by preventing unnecessary rise, etc., of solder. CONSTITUTION:A substrate 1 is inverted upside down with a rod 11 of a connector 10 inserted to a through-hole 2 of the substrate 1. A ring solder 3' is fit to an upper part of the rod 11 and a thermal contracting tube 7 is fit between the rod 11 and a pin part 12 and between the rod 11 and a contact part 13. Then, the ring solder 3' is heated and fused in a vapor tank under the condition, and poured into a clearance between the through-hole 2 and the rod 11; at this time, the tube 7 contracts due to heating and fits closely to both ends of the rod 11. Thereby, a fillet 3a of fused solder 3 is formed only between the through-hole 2 and the tube 7 and solder rise to the pin part 12 is restricted forcibly by the tube 7.

Description

[Detailed Description of the Invention] [Summary] Soldering is a method for mounting circuit components such as packages and connector leads in through-holes of a printed circuit board by soldering them. When soldering components, the purpose of soldering is to limit the soldering range easily and reliably. For circuit components to be soldered to through-holes or pads on the board, heat must be applied in advance between the soldering points and the points where soldering is not required. Attach the shrinkable tube and melt the solder to attach the tube.

[Industrial application field]

The present invention relates to a soldering method when circuit components such as packages and connector leads are soldered and mounted in through holes of a printed circuit board.

In recent years, as printed circuit boards have become denser and faster, connector leads have been soldered to through-holes to shorten wire length and space when mounting connectors on circuit boards. In addition, when it comes to connectors, there are not only male and female connectors.
A system in which both male and female parts are provided at both ends and three parts are directly connected is also being adopted.

[Conventional technology]

Conventionally, when soldering circuit component leads to through holes on a printed circuit board, there is a flow method in which the through holes and the lower ends of the leads are immersed in molten solder, and the solder rises between the two by capillary action. In addition, when a connector with male and female ends at the top and bottom ends is soldered to a through hole in the middle, ring solder is heated in a vapor tank and molten solder is filled between the through hole and the connector. There is also a haflo one type with preliminary soldering on the outside.

[Problem to be solved by the invention]

Incidentally, in all of the above conventional examples, soldering is performed within a predetermined range due to the relationship between the surface tension of the solder and the wetting force of the flux, and no means for restricting the soldering range is used. For this reason, the solder may rise or fall more than necessary from the through-hole portion, which may lead to various problems.

In particular, when soldering the middle part of a female and male connector to a through hole, if the solder reaches the upper contact part, the elasticity of the connector part may be impaired or a short circuit may occur at the contact part. Furthermore, if the solder drips down to the lower bottle part, the bottle diameter increases and it becomes impossible to insert it into the mating connector. Furthermore, since the printed circuit board on which this type of connector is used has a large heat capacity, it is impossible to replace the connector, and if such a failure occurs, not only the connector but also the entire printed circuit board must be discarded.

The present invention has been made in view of the above, and an object of the present invention is to easily and reliably limit the soldering range of circuit components when soldering circuit components to through-holes, etc. of a board. Soldering is all about providing a method.

[Means for Solving the Problems] In order to achieve the above object, the method for soldering circuit components of the present invention is such that, for example, when a circuit component of a male and female connector is soldered to a through hole of a board, an intermediate soldering method is provided. For soldering, a heat-shrinkable tube is fitted in advance between the rond and the pin and contact parts at both ends that do not require soldering.

Then, with this tube attached, solder is melted and filled between the through hole and the iron, and soldering is performed.

[Effect]

The above soldering method involves applying solder between the middle rond of the connector and the through hole using a heat-shrinkable tube.
The rising or falling of pins and contacts is reliably restricted, and areas where soldering is not required are appropriately protected.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

In FIG. 1, a case will be described in which the present invention is applied to a male and female connector. First, in (a), to describe the component mounting structure on a printed board, reference numeral 1 is a motherboard board, and this board 1 is provided with a plurality of through holes 2 for connectors, and male and female connectors are installed in the through holes 2. 10 will be implemented. This connector 10 has a male pin part 12 on one side of a rod 11 and a female bifurcated contact part 13 on the other side, and the contact part 13 is assembled to a guide block 14, and the intermediate rod 11 is inserted into the through hole 2 and attached with solder 3 to be mounted. In this way, the motherboard base I
A guide zinc 14 is provided above I along with the contact portion 13.
is installed, and the daughter board 4 is directly inserted and connected to this contact portion 13 using an edge connector 5. Furthermore, the pin portion 12 protruding downward from the board is connected to the I10 connector 6.
The connector 10 connects the motherboard board 1, daughter board 4 and I
10 connectors 6 are directly connected.

Therefore, to describe the soldering of the connector 10, first, the rod 11 of the connector 10 is inserted into the through hole 2 of the board 1, and then the connector 10 is turned upside down as shown in (b).

Then, a ring solder 3' is fitted into the upper part of the rod 11, and a heat-shrinkable tube 7 is fitted between the rod 11, the pin part 12, and the contact part 13. In this state, the ring solder 3' is heated and melted in the vapor tank to form the through hole 2.
In this case, the tube 7 shrinks due to heating and is tightly fitted to both ends of the rod 11. Therefore, as shown in (C), a fillet 3a of melted solder 3 is formed only between the through hole 2 and the tube 7, and as the solder rises to the pin part 12, the solder rises to the contact part 13 by the tube 7. limited to.

In this way, in the connector 10, only the intermediate rod 11 excluding the pin portions 12 and contact portions 13 at both ends after the tube 7 is soldered to the through hole 2, and the pin portions 12 and contact portions 13 are prevented from being attached with the solder 3. It will be protected by.

Referring to FIG. 2, another embodiment of the present invention is described in which a PGA package 20 and a glue board 21 are connected to a substrate 1.
The tube 7 is attached to the package 20 side of each lead 21 in a reflow soldering method.

As a result, when the solder 3 of the pad 22 melts and rises along the lead 21, it is similarly restricted by the tube 7, thereby preventing the lead 21 from becoming rough due to the solder. Therefore, damage to the wire 23 when the modified wire 23 is wired below the package 20 is avoided.

Note that heat-shrinkable tubes may also be used when soldering the leads of ordinary packages and connectors to through-holes in the board.

〔Effect of the invention〕

As described above, according to the present invention, when mounting circuit components on a printed circuit board, the soldering range is arbitrarily limited using a heat shrink tube, so that there is no excessive solder build-up or This is particularly effective in preventing the connectors from falling down and protecting the pin portions and contact portions at both ends of the male and female connectors. Also, damage to the modified wire can be prevented.

Soldering is easy because the tube is simply attached to the front, and it is highly reliable because it does not affect thermal expansion.

The tube can be attached at any location and its length can be determined freely, making it easy to handle.

[Brief explanation of drawings]

1(a) is a sectional view showing the mounting state when the present invention is applied to soldering male and female connectors; FIG. 1(b) and (C) are sectional views showing an embodiment of the soldering method; The figure is a side view showing another embodiment of the present invention. is a heat-shrinkable tube, O is a female and male connector, 1 is a rod, 2 is a pin part, and 3 is a contact part.

Claims (1)

[Claims] A heat-shrinkable tube is placed in advance between the soldering location and the non-soldering location of the circuit component (10 or 20) to be soldered to the through hole (2) or pad (22) of the board (1). (7)
A method for soldering circuit components, characterized in that: the tube (7) is attached, and the solder is melted while the tube (7) is attached.