Borehole survey instrument
US4485563A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 3, 1982 |
| Grant date | Dec 4, 1984 |
| Priority date | — |
| Expiry date | Dec 3, 2002 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B47/022
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A borehole survey instrument is provided having a meniscus type floating compass member with indicia thereon for indicating azimuth and inclination. A light source is disposed below the indicia for illuminating the indicia upward through the liquid through which the meniscus type floating compass member floats. A lens system is provided for focusing the image of the illuminated compass member upon a film disposed below the compass member. This arrangement permits the centering post for the compass member to be of minimum diameter consistent with rigidity requirements and permits a high angle compass member to indicate angles of inclination approaching ninety degrees. A multiple light bulb light source is utilized and each light bulb is mounted in a manner which permits a single light bulb to illuminate the entire compass member. A hand-held programming and diagnostic unit is provided which may be momentarily electrically mated with the borehole survey tool to input a programmed timed delay and diagnostically test both the condition of the light bulbs utilized as the illumination source and the state of the batteries within the instrument. This hand-held programmable unit eliminates…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.