Access control system for controlling the access to at least one space, and product including an access control system
US6147621A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 20, 1998 |
| Grant date | Nov 14, 2000 |
| Priority date | — |
| Expiry date | Jan 20, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG07C2009/00793
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
In an access control system (8)--which comprises a transponder communication device (9) and at least two transmission coils (11, 12) connected to the transponder communication device (9), for receiving transponder signals, of which a first transmission coil (11) is associated with a first door (2), and which comprises a first activation device (18 associated with the first transmission coil (11) and the first door (12), and which comprises a first door opener (23) for the first door (2) and a logic device (45) for activating the first door opener (23)--the two transmission coils (11, 12) have arbitrarily large receiving ranges and the first transmission coil (11) and at least one further transmission coil (12) are followed by amplitude detector (34, 36) by which the amplitudes of the transponder signals supplied by the two transmission coils (11, 12) can be detected and the logic device is arranged after the amplitude detector (34, 36) and adapted to detect a condition in which the amplitude of the transponder signal supplied by the first transmission coil (11) is greater than the amplitude supplied by the second transmission coil (12), which first door opener (23) for the first do…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.