United States Patent
US Patent 7703197: Process for depopulating a circuit board
US 7703197 ยท granted 2010-04-27
Abstract
Apparatus and methods for removing components from a circuit board. A conveyor transports circuit boards having components attached with solder through a heating section. When the solder has been melted by application of electromagnetic radiation, the circuit board is subjected to mechanical forces that dislodge the components to be removed from the circuit board. In one embodiment, the electromagnetic radiation is supplied by heaters operating at color temperatures in the vicinity of 973 Kelvin. The components are recovered in a form that allows their reuse.
| Patent Number | 7703197 |
|---|---|
| Title | Process for depopulating a circuit board |
| Filed | 2005-07-01 |
| Granted | 2010-04-27 |
| Inventor(s) | Moltion; James R. |
| CPC Classification | B23P 19/00 |
| Number of Claims | 30 |
Abstract
Apparatus and methods for removing components from a circuit board. A conveyor transports circuit boards having components attached with solder through a heating section. When the solder has been melted by application of electromagnetic radiation, the circuit board is subjected to mechanical forces that dislodge the components to be removed from the circuit board. In one embodiment, the electromagnetic radiation is supplied by heaters operating at color temperatures in the vicinity of 973 Kelvin. The components are recovered in a form that allows their reuse.
Claim 1
A method of producing a removed item originally soldered to a printed circuit board, the printed circuit board readily absorbing infrared energy at a certain set ofwavelengths, said method comprising the steps of: transporting said printed circuit board containing the soldered item to be removed from a printed circuit board entry port to a printed circuit board exit port of an apparatus configured to remove saiditem; controlling a travel speed of said printed circuit board; heating a solder of the item to be removed, by applying to the printed circuit board containing the soldered item to be removed, infrared radiation at one or more selected wavelengthsdifferent from the certain wavelengths that are readily absorbed by said printed circuit board, the one or more selected wavelengths applied being readily absorbed by the solder and having sufficient energy to melt the solder of the item to be removed,the one or more selected wavelengths applied being not readily absorbed by the printed circuit board, such that the printed circuit board exits the exit port of the apparatus at a temperature that can be grasped with a bare hand; applying mechanicalforces to the printed circuit board h
Claims
30 totalA method of producing a removed item originally soldered to a printed circuit board, the printed circuit board readily absorbing infrared energy at a certain set ofwavelengths, said method comprising the steps of: transporting said printed circuit board containing the soldered item to be removed from a printed circuit board entry port to a printed circuit board exit port of an apparatus configured to remove saiditem; controlling a travel speed of said printed circuit board; heating a solder of the item to be removed, by applying to the printed circuit board containing the soldered item to be removed, infrared radiation at one or more selected wavelengthsdifferent from the certain wavelengths that are readily absorbed by said printed circuit board, the one or more selected wavelengths applied being readily absorbed by the solder and having sufficient energy to melt the solder of the item to be removed,the one or more selected wavelengths applied being not readily absorbed by the printed circuit board, such that the printed circuit board exits the exit port of the apparatus at a temperature that can be grasped with a bare hand; applying mechanicalforces to the printed circuit board h