Apparatus for irradiation of printed wiring boards and the like
US5040236A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 18, 1990 |
| Grant date | Aug 13, 1991 |
| Priority date | — |
| Expiry date | Jul 18, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K2203/1572
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An open-weave conveyor moves a printed wiring board through a region of radiant energy. The conveyor has a plurality of supporting projections extending from the major surface of the conveyor to minimize engagement between the conveyor and the board, providing at least three projections supporting each board above the open-weave conveyor to eliminate a shadow effect caused by radiation blocked by conveyor strands. Guides move the conveyor along an arcuate path away from the printed wiring board in the radiation region, assuring irradiation of the entire printed wiring board surface. This technique is advantageous for simultaneously irradiating both sides of a board during a dry film solder masking technique. The solder mask is radiated to promote cross-linking of the film polymer. To reduce thermal shock and abrupt temperature rise in the workpiece, the ultraviolet source includes a water envelope to absorb infrared radiation. A series of irradiation devices, one with and one without the aforementioned water envelope, may be utilized. A liquid component utilized in the dry film solder masking tecnique to fill voids and irregularities in the printed wiring board surface irradiated i…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.