| 摘要 |
PURPOSE:To remove molten solder in a carrying hole positively by stopping the operation of pull-up of a frame once and pulling up it when an external leading- out lead unified with a lead frame with the carrying hole is dipped in molten solder in a solder tank, pulling up the lead frame and plating it by solder dipping. CONSTITUTION:A frame in which external leading-out leads 2 and a lead frame 1 with a carrying hole 5 are unified is dipped in molten solder 12 filled into a solder tank 11, and the lad frame 1 is plated by solder dipping. When the carrying hole 5 is filled with solder 12 at that time, the following operation is executed because the next tie bar cutting process gets trouble. That is, when the frame 1 and the leads 2 are dipped in molten solder 12 and these frame and leads are pulled up, the operation of pull-up is stopped once, these frame and leads are held form several sec and molten solder 12b in the hole 5 is flowed out and dropped when one part of the hole 5 is separated from the surface 12a of a solder liquid, and pull-up is continued when there is no solder 12 in the hole 5. |
