Patent US3876471A successfully refreshed from Google Patents.
US3876471A
Expired / Lapsed
US
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Borehole electrolytic power supply
Assignee: Sperry Sun Inc
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Filing: 1973-09-12
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Granted: 1975-04-08
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Expires: 1993-09-12
Abstract
Abstract Power supply apparatus for generating electrical energy for a sustained period of time within the environment of an earth borehole filled with drilling mud. The power supply is used in a downhole well logging system for supplying electrical energy to circuitry located down within the borehole and includes an elongate magnesium electrode having a plurality of circumferentially spaced, longitudinally extending slots formed therein. The electrode is located in a special sub within the drill pipe and a potential difference is produced between the magnesium electrode and the walls of the steel drill pipe due to electrolytic decay of the metals, when a conductive drilling mud is located therebetween.
Inventors
- 👤 Jack W Jones
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:31
CPC Classifications
H; H01; H01M; H01M6/00; H01M6/30; H01M6/32; E; E21; E21B; E21B17/00; E21B41/00; E21B41/0085; E21B47/00; E21B47/12
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
110 words
A downhole power source for generating electrical energy within an earth borehole, comprising: a hollow cylindrical drilling pipe; a cylindrical electrode positioned coaxially within said pipe to define an annular space therebetween and having a plurality of circumferentially spaced, longitudinally extending slots formed therein, said electrode being formed from a material having a different electrochemical potential than said drilling pipe; a plurality of radially extending, circumferentially-spaced struts between said pipe and said electrode to hold said electrode in position; means for insulating said electrode from said drilling pipe; and a conductive drilling mud located in the annular space between said electrode and said drilling pipe to produce an electrical potential
Claim 2
Dependent Claim
110 words
A downhole power source for generating electrical energy within an earth borehole, comprising: a hollow cylindrical drilling pipe; a cylindrical electrode positioned coaxially within said pipe to define an annular space therebetween and having a plurality of circumferentially spaced, longitudinally extending slots formed therein, said electrode being formed from a material having a different electrochemical potential than said drilling pipe; a plurality of radially extending, circumferentially-spaced struts between said pipe and said electrode to hold said electrode in position; means for insulating said electrode from said drilling pipe; and a conductive drilling mud located in the annular space between said electrode and said drilling pipe to produce an electrical potential
Claim 3
Dependent Claim
25 words
A downhole power source for generating electrical energy within an earth borehole as set forth in claim 1 wherein said drilling pipe is made of
Claim 4
Dependent Claim
33 words
A downhole power source for generating electrical energy within an earth borehole, as set forth in claim 1, which also includes: means for moving said conductive drilling mud through said annular space to
Claim 5
Dependent Claim
44 words
A downhole power source for generating electrical energy within an earth borehole, as set forth in claim 1, which also includes: a d. c. to d. c. converter having its input terminals connected between said electrode and said drilling pipe to amplify the potential
Claim 6
Dependent Claim
30 words
A downhole power source for generating electrical energy within an earth borehole, as set forth in claim 1, wherein, the resistivity of said conductive drilling mud is less than 15
Claim 7
Dependent Claim
125 words
A special telemetry sub for inclusion in the drill pipe string of an earth borehole drilling apparatus, said sub comprising: a section of hollow steel drill pipe having threads at either end for engagement with drill pipes within a string; an elongate cylindrical telemetry instrument package positioned coaxially within said pipe to define an annular space therebetween, said package being held in position by a plurality of radially extending, circumferentially spaced struts; a cylindrical electrode attached to and insulated from the end of said coaxial instrument package, said electrode being formed from a material having a different electrochemical potential than said drill pipe; means for connecting to said instrument package the potential generated between said electrode and said drill pipe when a conductive drilling mud
Claim 8
Dependent Claim
125 words
A special telemetry sub for inclusion in the drill pipe string of an earth borehole drilling apparatus, said sub comprising: a section of hollow steel drill pipe having threads at either end for engagement with drill pipes within a string; an elongate cylindrical telemetry instrument package positioned coaxially within said pipe to define an annular space therebetween, said package being held in position by a plurality of radially extending, circumferentially spaced struts; a cylindrical electrode attached to and insulated from the end of said coaxial instrument package, said electrode being formed from a material having a different electrochemical potential than said drill pipe; means for connecting to said instrument package the potential generated between said electrode and said drill pipe when a conductive drilling mud
Claim 9
Dependent Claim
43 words
A special telemetry sub as set forth in claim 6 wherein: said telemetry instrument package includes a d. c. to d. c. converter having the input thereof connected across said drill pipe and said electrode to power said package from the potential difference
Claim 10
Dependent Claim
11 words
A special telemetry sub as set forth in claim 6 wherein:
Claim 11
Dependent Claim
32 words
A special telemetry sub as set forth in claim 8 wherein: said cylindrical electrode includes a plurality of circumferentially spaced, longitudinally extending slots formed therein to increase the effective surface area thereof.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-04-07 | 1978-10-07 | 1979-04-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-07 | 1982-10-07 | 1983-04-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-07 | 1986-10-07 | 1987-04-08 | $7700.00 | Window Closed / Lapsed |