Soldering apparatus of a reflow type

A soldering apparatus (4) of a reflow type contains a preheating chamber (8, 9) and a reflow chamber (10) which are provided with a plurality of heaters (11) for heating printed circuit boards (1) with chips (2) temporarily mounted thereon with solder pastes (3) during conveyance by a conveyor (5). The heaters (11) are provided with a screening member (26) and/or a partition member (12) so as to prevent direct radiation of radiant heat from the heaters (11) into the chambers and onto the printed circuit boards (1) and to provide a unform air flow so as to be blown uniformly onto the printed circuit boards (1). The heaters (11) are arranged so as to heat them in such a manner as to ascend temperatures in the order from an inlet (6) to an outlet (7) so as to become higher with a predetermined temperature differential from the previous heater, thus removing bubbles generated upon fusion of the solder pastes (3) and minimizing a heat shock exerted on the chips (2) when they are heated. The soldering apparatus is further provided with a combustion unit (20) with a catalyst (23) for removing fume and odoring gases generated in the chamber and for circulating the heated air after removal of such fume and gases. These arrangement can provide printed circuit boards of higher quality and with high productivity.