| 摘要 |
PURPOSE:To make thick a solder-plated film on lead pins and to contrive the improvement of the aging resistance of the lead pins by a method wherein the lead pins are dipped in a molten solder bath in a state that the lead pins are inserted in the through holes of a jig plate and thereafter, a board for mounting electronic components is raised in the almost vertical direction as the jig plate is left on the molten solder bath. CONSTITUTION:In case the periphery of an electronic component mounting part 3 and lead pins 4 are bonded together in solder joint and at the same time, a solder- plated layer is formed on the pins 4, a jig plate 6 having through holes 61, in which the pins 4 are inserted, is used and after the pins 4 and board 1 for mounting electronic components are dipped in a molten solder bath 7, the board 1 only is raised in the almost vertical direction as the plate 6 is left on the bath 7. Accordingly, as a heating of the substrate due to a fused solder is interrupted by the jig plate, heat dissipation from the surfaces of the pins 4 and so on is comparatively quickened after the board 1 is raised from the bath 7 and the film thickness of the solder-plated layer on the pins 4 becomes thick. Thereby, the film thickness of the solder-plated layer on the surfaces of the lead pins is uniform and thick and the aging resistance of the lead pins is improved. |
