Geophone
US4285054A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 27, 1979 |
| Grant date | Aug 18, 1981 |
| Priority date | — |
| Expiry date | Jul 27, 1999 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V1/181
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A geophone comprising an annular coil-mass and a permanent magnet assembly positioned inside the annular coil-mass with their longitudinal axes generally coinciding to place the coil-mass in the magnetic field of the permanent magnet assembly. Spring spiders support the coil-mass on the permanent magnet assembly for axial and rotational movement relative to the permanent magnet assembly along and around the longitudinal axis thereof. Contacts extend outside the housing of the geophone to connect the geophone into an electrical circuit. Two axially spaced, parallel, spring spiders or diaphragm springs electrically connect the outside contacts to the terminals of the coils of the coil-mass.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.