Hitachi, Ltd.

Tomoyuki Ohmura

Tetsuya Nakatsuka

Masahide Okamoto

Asao Nakano

This invention relates to a packaging method using lead-free solder, characterized by including a reflow-soldering step in which a surface mount device is soldered to a circuit board with a lead-free solder paste; an inserting step in which the lead or terminal of a insertion mount device is inserted into the circuit board; a step in which a warp preventing jig is attached to the circuit board; a flux applying step in which flux is applied to the foregoing circuit board; a preheating step in which, after applying flux, the lower surface of the circuit board is preheated; a flow-soldering step in which the upper surface of the circuit board the lower surface of which was preheated in the preheating step is heated, and by applying lead-free solder paste to the lower surface of the circuit board, the lead or terminal of the insertion mount device is flow-soldered to the circuit board; and a temperature controlling step where temperatures of both surfaces of a circuit board are adjusted, the upper surface of the circuit board is cooled or heated and the lower surface of the said circuit board is cooled, immediately after soldering in the flow-soldering step.

Packaging method using lead-free solder

The present invention relates to a wave soldering method and a wave soldering apparatus using lead-free solder comprising a wave soldering step in which the lower side of a substrate with leads of component parts inserted in through-holes formed in the substrate from the upper side is wave soldered by contact with a molten lead-free solder blowout at a wave soldering portion provided in a chamber, and a cooling step in which an inert gas in the chamber is recirculated and cooled and is blown to the lower side of the substrate wave soldered with the lead-free solder in the wave soldering step and being conveyed, to cool the lower side of the substrate, at a blowing portion provided adjacently to the wave soldering portion in the chamber, and an apparatus therefor.

Wave soldering method using lead-free solder, apparatus therefor, and wave-soldered assembly

A packaging method using lead-free solder, characterized by including a reflow-soldering step in which a surface mount device is soldered to a circuit board with a lead-free solder paste; an inserting step in which the lead or terminal of a insertion mount device is inserted into the circuit board; a step in which a warp preventing jig is attached to the circuit board; a flux applying step in which flux is applied to the foregoing circuit board; a preheating step in which, after applying flux, the lower surface of the circuit board is preheated; a flow-soldering step in which the upper surface of the circuit board the lower surface of which was preheated in the preheating step is heated, and by applying lead-free solder paste to the lower surface of the circuit board, the lead or terminal of the insertion mount device is flow-soldered to the circuit board; and a temperature controlling step where temperatures of both surfaces of a circuit board are adjusted, the upper surface of the circuit board is cooled or heated and the lower surface of the circuit board is cooled, immediately after soldering in the flow-soldering step.

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Tokyo, Japan

Tomoyuki Ohmura