Keyboard assembly
US4476355A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 3, 1983 |
| Grant date | Oct 9, 1984 |
| Priority date | — |
| Expiry date | Nov 3, 2003 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01H2227/026
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A keyboard assembly including a printed circuit board having a plurality of dual channel switch sites thereon including a plurality of contacts defining keypads and dome-shaped conductive resilient elements generally called domes, coacting with the keypads which in their relaxed state maintain the switch open and in their depressed and tripped state close the switch. The domes are provided with a centrally disposed upwardly extending projection or dimple to be engaged by an actuator or button and a peripheral portion defining a contact surface for continually engaging one of the contacts on the switch site. The other contacts are engaged by a central portion of the dome when it is depressed and tripped. Each switch site includes a ring-shaped contact in continuous engagement with the peripheral portion of the dome and a pair of triangular or delta-shaped contacts disposed within the ring-shaped contact and engageable with the central portion of the dome when it is depressed and tripped. Alternately, the switch site may contain a single contact within the ring-shaped contact.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.