Electronic security device
US4396914A · kind A · utility
34Cited by
15References
11Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jun 30, 1981 |
| Grant date | Aug 2, 1983 |
| Priority date | — |
| Expiry date | Jun 30, 2001 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG07C9/215
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
An electronic security device includes a memory and a card reader which reads a combination code and calculation data from a key card. An electronic circuit compares the content of the memory with the combination code and enables the lock device if a match is found. If the key card is a new one the circuit calculates a new combination code by applying the calculation data to the memory content and, if this new combination code matches that on the key card the memory is loaded with the new combination code.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.