US3715655A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Induction logging apparatus having a common series element for nulling
Assignee: Texaco Inc
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Filing: 1970-12-30
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Granted: 1973-02-06
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Expires: 1990-12-30
Abstract
Abstract Induction logging apparatus employing a transmitter coil with a receiver coil spaced therefrom along a common axis. It has an excitation circuit for the transmitter coil and an output circuit for signals induced in the receiver coil, thus a common circuit for nulling the direct coupled receiver signals. All three of the circuits are located on a logging sonde that may be run down a well.
Inventors
- 👤 D Dowling
- 👤 G Atwood
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 07:54
CPC Classifications
G; G01; G01V; G01V3/00; G01V3/18; G01V3/26; G01V3/28
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
145 words
An induction logging tool comprising in combination an elongated sonde having a cable attached thereto for running said sonde in a well, a transmitter coil carried by said sonde and having an axis, a receiver coil carried by said sonde and being located spaced from said transmitter coil longitudinally along said axis, said receiver coil having an axis located in common with said transmitter coil axis, an excitation circuit for energizing said transmitter coil including a capacitive reactance element in series with said transmitter coil, and an output signal circuit for carrying signals from said receiver coil dependent upon formation conditions surrounding said well, and including said capacitive reactance element in series with said receiver coil, said capacitive reactance element being common to both said excitation and output signal circuits for causing a bucking signal to eliminate undesired direct coupled signals from said output circuit.
Claim 2
Dependent Claim
145 words
An induction logging tool comprising in combination an elongated sonde having a cable attached thereto for running said sonde in a well, a transmitter coil carried by said sonde and having an axis, a receiver coil carried by said sonde and being located spaced from said transmitter coil longitudinally along said axis, said receiver coil having an axis located in common with said transmitter coil axis, an excitation circuit for energizing said transmitter coil including a capacitive reactance element in series with said transmitter coil, and an output signal circuit for carrying signals from said receiver coil dependent upon formation conditions surrounding said well, and including said capacitive reactance element in series with said receiver coil, said capacitive reactance element being common to both said excitation and output signal circuits for causing a bucking signal to eliminate undesired direct coupled signals from said output circuit.
Claim 3
Dependent Claim
145 words
An induction logging tool comprising in combination an elongated sonde having a cable attached thereto for running said sonde in a well, a transmitter coil carried by said sonde and having an axis, a receiver coil carried by said sonde and being located spaced from said transmitter coil longitudinally along said axis, said receiver coil having an axis located in common with said transmitter coil axis, an excitation circuit for energizing said transmitter coil including a capacitive reactance element in series with said transmitter coil, and an output signal circuit for carrying signals from said receiver coil dependent upon formation conditions surrounding said well, and including said capacitive reactance element in series with said receiver coil, said capacitive reactance element being common to both said excitation and output signal circuits for causing a bucking signal to eliminate undesired direct coupled signals from said output circuit.
Claim 4
Dependent Claim
145 words
An induction logging tool comprising in combination an elongated sonde having a cable attached thereto for running said sonde in a well, a transmitter coil carried by said sonde and having an axis, a receiver coil carried by said sonde and being located spaced from said transmitter coil longitudinally along said axis, said receiver coil having an axis located in common with said transmitter coil axis, an excitation circuit for energizing said transmitter coil including a capacitive reactance element in series with said transmitter coil, and an output signal circuit for carrying signals from said receiver coil dependent upon formation conditions surrounding said well, and including said capacitive reactance element in series with said receiver coil, said capacitive reactance element being common to both said excitation and output signal circuits for causing a bucking signal to eliminate undesired direct coupled signals from said output circuit.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-02-06 | 1976-08-07 | 1977-02-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-02-06 | 1980-08-07 | 1981-02-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-02-06 | 1984-08-07 | 1985-02-06 | $7700.00 | Window Closed / Lapsed |