Capacitive squeeze protecting device
US7504787B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 12, 2003 |
| Grant date | Mar 17, 2009 |
| Priority date | — |
| Expiry date | Jan 28, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K2017/9602
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A capacitive squeeze protecting device having a high degree of security and flexibility for automatic doors. The squeeze protecting device is arranged to detect the presence of an object in a protection field comprising a housing and an antenna unit connected to a detecting circuit, which circuit is arranged to, via said antenna unit, detect capacitive variations in an electric or electromagnetic field at said antenna unit. The detecting circuit comprises means connected to said antenna unit arranged to detect a variation of the pressure at said antenna unit caused by a compressive force applied at said housing, wherein the presence of conductive as well as non-conductive object can be detected. Furthermore, the invention includes a system and methods for detecting for detecting the presence of an object in a protection field at a door.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.