Keyboard switch assembly having printed circuit board with plural layer exposed contacts and undersurface jumper connections
US4045636A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 28, 1976 |
| Grant date | Aug 30, 1977 |
| Priority date | — |
| Expiry date | Jan 28, 1996 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S428/901
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A printed wiring board for a keyboard switch assembly for electronic apparatus, such as electronic calculators, comprising a self-supporting insulative board having a plurality of elongated connectors on one surface thereof, at least some of the conductors having terminal portions for cooperating with switch elements. A layer of insulating material covers the one surface of the board and the conductors excluding the terminal portions. Each of the terminal portions has a coating of conductive ink thereon and a jumper element also formed of conductive ink is coated on the insulating layer crossing at least one of the conductors embedded therein and joining at least two of the terminal portion coatings. The conductive ink is preferably a noble-metal filled resin compound, such as silver epoxy, screen printed onto the insulating layer and terminal portions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.