Keyswitch
US4342892A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 8, 1980 |
| Grant date | Aug 3, 1982 |
| Priority date | — |
| Expiry date | Aug 8, 2000 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01H2011/062
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A keyswitch includes a tubular plunger with a body slidable vertically in an open-top housing that has a bottom wall supporting the lower end of a coil spring extending up around a pair of opposed upright spring contact strips, the lower ends of which extend through the bottom wall. The inside of the plunger is provided with a cross member that normally separates the upper ends of the contact strips, but permits them to engage each other when the plunger is pushed down. The contact strips are substantially identical. Each has at least two parallel slits extending downwardly from its upper end to form a plurality of narrow contact fingers beside a wider contact finger that is wide enough to be engaged by the narrow contact fingers of the opposing contact strip.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.