Electromagnetic lock having distance-sensing monitoring system
USRE46832E1 · kind E1 · reissue
Assignee
Inventors
Key dates
| Filing date | Sep 1, 2016 |
| Grant date | May 8, 2018 |
| Priority date | — |
| Expiry date | Sep 1, 2036 |
Classification
- Technology area (CPC —)General
Abstract
An emergency exit door lock system configured to cooperate with a door hinged in a door frame for sensing when a person attempts to open the door, and for allowing the door to open after a subsequent delay. The system comprises an electromagnet affixable to a door frame for electromagnetically attracting an armature resiliently affixed at a variable armature separation distance to an armature mounting device, the device being affixable to the door. A proximity sensor including an analog Hall Effect device is mountable to the frame for detecting movement of the door away from a closed position. A controller, such as a micro-controller, receives a signal from the sensor and causes an alarm as a function of the signal. The signal is indicative of the armature separation distance, the controller being calibrate-able to provide a door alarm signal and door opening signal at any desired value of the armature separation distance.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.