SOLDERING METHOD

摘要

PURPOSE:To prevent the generation of soldering defects such as icicles and solder bridges by passing molten solder in the direction opposite from an object to be soldered so as to contact with said body and specifying the flow rate of the molten solder. CONSTITUTION:The molten solder is ejected from a nozzle 13 by operating an impeller 14. The molten solder is ejected through an aperture in which an aperture control plate 13b is determined by a flow passage 13c. The molten solder further flows through the passage 13c and falls from the top end thereof into a solder tank 12. A printed circuit board (a) which is preliminarily coated with a flux and is preheated is carried into the soldering device in the state of raising forward and is brought into contact with the flowing molten solder, then the circuit board is warped by the effect of heat and the parts required to be soldered are wetted with the solder. The printed circuit board is detached from the flow of the molten solder as the circuit board is conveyed. The flow rate of the molten solder in the detaching position is adjusted to >=15cm/sec. The tailing end of the molten solder sticking to the soldered part is oriented in the flow direction of the molten solder and the tail end thereof is torn off by the molten solder and is carried away together with the molten solder.