Electronic compass
US5850624A · kind A · utility
173Cited by
41References
74Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Oct 18, 1995 |
| Grant date | Dec 15, 1998 |
| Priority date | — |
| Expiry date | Oct 18, 2015 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B47/022
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An electronic compass (10) for use in a boring tool (12) which will provide an orientation of the boring tool relative to the earth's magnetic field. In addition, a more straightforward left or right deviation from an initial bearing can be determined. The invention can correct for pitch angle and roll angle variation as well. The magnetic field is sensed by an axial magnetic field (12), a radial magnetic field sensor (18) and a plane-normal magnetic sensor (24) which are preferably magnetoresistive sensors.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.