Redundant sensing edge for a door for detecting an object in proximity to the door edge
US5027552A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 16, 1990 |
| Grant date | Jul 2, 1991 |
| Priority date | — |
| Expiry date | Aug 16, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K2217/96078
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A redundant sensing edge for a door to protect persons, equipment and the door from impact damage by actuating a device upon detecting an object in proximity to the door edge. The sensing edge includes an elongate outer sheath compressible upon application of external pressure. A force sensing switch is positioned within the elongate outer sheath for sensing the application of force to the sheath. Upon force being applied to the sheath, the force sensing switch actuates the device for controlling the door. The sensing edge also includes a proximity sensing switch for detecting the presence of an animate object in proximity to the door edge. The proximity sensing switch includes an electrical circuit positioned near the elongate sheath and a control circuit for detecting changes in the capacitance of the electrical circuit. An animate object in proximity to the elongate sheath changes the capacitance of the electrical circuit. The control circuit detects the change in capacitance and in response to the change in capacitance actuates the device. Thus, the device is actuated either upon the detected presence of an animate object in proximity to the sheath or upon the application of fo…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.