Keyboard assembly and components therefor
US4367380A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 27, 1980 |
| Grant date | Jan 4, 1983 |
| Priority date | — |
| Expiry date | Aug 27, 2000 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01H2013/566
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A keyboard switch assembly includes a membrane switch matrix formed on a baseplate. There are a plurality of individual pressure applicators or keys which are mounted on the baseplate in a keyboard array. The keys are supported adjacent the membrane switch panel with each key being used to effect contact closure at a particular area of the membrane switch. Each key includes a movable plunger, a housing to support the plunger, a first coil spring biasing the plunger away from the membrane switch and a keytop affixed to the plunger. A second coil spring is seated upon the membrane switch matrix and provides the means for application of electrical contact closure pressure. Each key housing includes an enclosure which is accessible from the top of the housing. The closure is adapted to receive and retain a cam follower which controls movement of the plunger. The key housings further include a hook which can support a torsion rod. A torsion rod may be attached to an elongated keytop in an adjacent row to prevent binding of the plunger carrying the elongated keytop.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.