System and method of detecting the proximity of an alternating magnetic field
US4362992A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 30, 1978 |
| Grant date | Dec 7, 1982 |
| Priority date | — |
| Expiry date | Jan 30, 1998 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V3/08
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A system for, and a method of, detecting the proximity of a source of an alternating magnetic field, such as that emanating from power transmission cables, comprising a sensor coil sensitive to the magnetic field under detection, processing means to derive from the signal induced in the coil a warning signal indicative of the proximity of the magnetic field under detection, and cancelling means operable to cancel the earth's field in the region of the sensor coil. The sensor coil may be one of a pair operable to provide a signal representative of the directional heading of the magnetic field under detection, with respect to the system, which embodiment is particularly useful in helicopters for detecting the proximity of power cables.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.