Solder leveling method and apparatus
US4869418A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 9, 1988 |
| Grant date | Sep 26, 1989 |
| Priority date | — |
| Expiry date | Nov 9, 2008 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K3/3468
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A method and apparatus for producing flush solder fill over recessed pins and over passage holes in circuitized substrates. A substrate carrying rack is immersed in a vessel of molten solder after it has been similarly immersed in a flux bath. While in the molten solder, the rack is vigorously agitated. The rack is then withdrawn from the molten solder and is pivoted upwardly while positioned over the molten solder. Simultaneously, an anvil is rotated from a home position to an impact position at precisely the correct moment. With the solder still molten on the substrate surfaces, the rack is then permitted to descend and is positively biased to strike the anvil thereby dislodging any excess molten solder. A unique supporting arrangement for the rack insures that only a minimum of mass acutally impacts against the anvil while insuring the effectiveness of the operation. Each cantilevered arm from which a rack is suspended is temporarily supported during the impacting operation after which the support member is withdrawn. Also, a solder pot of unique design and operation is provided to assure rapid, complete heating of substrates while eliminating contamination thereof by dross and …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.