Computer keyboard circuitry
US3932866A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 24, 1974 |
| Grant date | Jan 13, 1976 |
| Priority date | — |
| Expiry date | Jul 24, 1994 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03M11/20
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A computer keyboard circuit for preventing development of fallacious signals by bouncing or chattering of the keyboard switch contacts, which circuit includes means for delivering a proper output signal to one of several output lines in response to actuation of one of the keyboard switches from a first normal condition to a predetermined actuated condition, and operable to then prevent delivery of an additional output signal to any of the output lines until complete return of the switch to its normal position. To achieve this result, each keyboard switch has two contacts responsive to actuation of the switch to its two different conditions respectively, and the circuitry requires that the switch return the entire distance from one contact to the other in order to condition the apparatus for production of a second output signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.