Fence sensor
US6456198B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 27, 2001 |
| Grant date | Sep 24, 2002 |
| Priority date | — |
| Expiry date | Mar 27, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08B13/122
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
It is an object of this invention to provide a fence sensor which can achieve an excellent detection stability without using a current for generating an electric field nor infrared rays. The fence sensor comprises a detection electrode (8); a reference electrode (9) insulated from the detection electrode (8); a chargeable member (4) insulated from both of the detection electrode (8) and the reference electrode (9); and a detection circuit (20) for detecting a change in the electrostatic capacitance between the detection electrode and the reference electrode that is generated by the presence of an object to be detected within a detection region of the detection electrode. In this fence sensor, the chargeable member is arranged such that at least a part of the chargeable member is situated within the detection region of the detection electrode. Further, the chargeable member is formed from a conductor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.