Patent · US Expired

Keypad device

US6912280B2 · kind B2 · utility

29Cited by
7References
4Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJul 22, 2002
Grant dateJun 28, 2005
Priority date
Expiry dateMay 28, 2023

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01H2225/012
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A keypad device for a mobile telephone or other device utilizing a keypad or keyboard is comprised of a flexible substrate and a keypad cover. The flexible substrate includes a plurality of keys affixed to the surface as well as a plurality first conductive strips associated with each key. The keypad cover is attached to the flexible substrate. The keypad cover typically includes holes that permit the plurality of keys to protrude through the keypad cover. In addition, the keypad cover further includes a plurality of second conductive strips that selectively contact a corresponding first conductive strip on the flexible substrate. The plurality of first conductive strips is coupled to ground and the plurality of second conductive strips is coupled to logic circuitry. Or, in another embodiment, both sets of conductive strips are coupled with the logic circuitry. The default position of the keypad device has each of the first conductive strips in contact with each of the corresponding second conductive strips. This creates a short circuit condition that prevents key signals from being received by the logic circuitry. When a particular key is depressed to the point where the first con…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.