| 摘要 |
PURPOSE:To improve the quality of a product and to reduce the cost by forming the heating air circulation passage having a heater and fan at the upper and lower parts of a conveyor in parallel and circulating the discharging air at the lower side by sucking it to the upper side. CONSTITUTION:A heater 69 and fan 66 are respectively arranged in plural pieces at the upper and lower sides of a conveyor 52 transporting an electronic part 55 and the descent and ascent circulation passages 68D, 68U of a heating air are formed. The electronic part 55 carried in by the conveyor 52 is preheated in a preheating zone 54, then subjected to soldering by being heated at the specified temp. in a soldering zone 54. In this case, due to the heating of the part 55 being done with an ideal temp. curve via the circulating heating air on the whole the terminal shock on the part 55 is surely prevented. Consequently the quality of a product is improved and the product cost is reduced because of the thermal efficiency being improved. |
