Keypad
US5936557A · kind A · utility
4Cited by
4References
10Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jun 25, 1997 |
| Grant date | Aug 10, 1999 |
| Priority date | — |
| Expiry date | Jun 25, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01H2239/032
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
In a keypad for an ATM or the like, in addition to mechanical keys (14) which when operated press areas (24) on a pressure sensitive layer (22) against a backing plate (32), and thereby close a corresponding normally-open switch (S), additional areas (26) are arranged as normally-closed switches A, with pressure applied by protrusions (36) on the backing plate (32). If the backing plate is removed, the switches A open, and the change is sensed by a monitoring circuit (48).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.