Computer keyboard with electrostatic discharge feature
US5335137A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 29, 1992 |
| Grant date | Aug 2, 1994 |
| Priority date | — |
| Expiry date | Jul 29, 2012 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01H2239/008
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A computer keyboard according to a preferred construction has multiple non-conductive keys and at least one conductive key mounted in a keyboard housing. The conductive key includes a molded plastic key body having conductive material embedded therein. Conductive plugs are electrically coupled and mounted to the conductive key body. An electrostatic discharge pad is provided on a switch assembly positioned beneath the keys of the keyboard. The discharge pad is coupled to ground through a path resistor. When the conductive key body is depressed to an activated position, the plugs engage the electrostatic discharge pads so that electrostatic charges of the user progressively dissipate to ground through the key body, plug, discharge pad, and path resistor. At least one of the path resistor or the plug has a resistance greater than the resistance of the conductive key body. In this manner, electrostatic charge is routinely dissipated from a computer user while insuring that the user is not shocked when he/she initially touches and operates the conductive key.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.