Method and apparatus for placing and electrically connecting components on a printed circuit board

摘要

A system for placing, soldering and inspecting component parts, such as soldered joints and electronic components, on a printed circuit board utilizes a transfer device for selecting and transferring specific electronic component parts to predetermined positions on a printed circuit board and holding each component part in the desired position by use of the transfer device during a reflow soldering operation to mechanically and electrically connect the component part to the printed circuit board. The reflow solderiung utilizes a laser beam for injecting thermal energy into each soldered joint to melt the soldered material. An infrared detector senses thermal radiation and/or reflected radiation from the heated solder material to discontinue the application of the laser beam to the solder material upon liquifaction of the solder material. The infrared detector also continues to sense the thermal radiation from the heated solder material during cool down to provide a signal which will be compared with a standard signal to determine the quality of the solder joint.