US5293121A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Isolated current monitoring circuit for measuring direct and high duty factor currents
Assignee: Raytheon Co
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Filing: 1992-10-08
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Granted: 1994-03-08
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Expires: 2012-10-08
Abstract
Abstract A method and circuit for measuring direct and high duty factor current in a conductor (1) with minimal interference with the operation of a monitored circuit. Current flow in the conductor is magnetically sensed with a transformer T1 having a primary winding connected electrically in series with the conductor (1). The transformer T1 is driven into saturation during a first time interval and brought out of saturation during a second time interval. After the transformer T1 is brought out of saturation, an output signal is provided which is proportional to the flow of current in the conductor (1).
Inventors
- 👤 Earl M. Estes, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 18:23
CPC Classifications
G; G01; G01R; G01R15/00; G01R15/14; G01R15/18; G01R15/183
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
130 words
An isolated current monitoring circuit for measuring direct and high duty factor current in a conductor comprising: transformer means for magnetically sensing current flow in said conductor, said transformer means including a transformer having a primary winding connected electrically in series with said conductor and a secondary winding; means, including an operational amplifier connected to said secondary winding, for driving said transformer into saturation during a first time interval; biasing means for preventing the introduction of an error signal into said operational amplifier; means for bringing said transformer out of saturation and operating said transformer as a current transformer during a second time interval; and means for providing an output signal, after the initiation of the second time interval, which is proportional to the flow of current in said conductor.
Claim 2
Dependent Claim
130 words
An isolated current monitoring circuit for measuring direct and high duty factor current in a conductor comprising: transformer means for magnetically sensing current flow in said conductor, said transformer means including a transformer having a primary winding connected electrically in series with said conductor and a secondary winding; means, including an operational amplifier connected to said secondary winding, for driving said transformer into saturation during a first time interval; biasing means for preventing the introduction of an error signal into said operational amplifier; means for bringing said transformer out of saturation and operating said transformer as a current transformer during a second time interval; and means for providing an output signal, after the initiation of the second time interval, which is proportional to the flow of current in said conductor.
Claim 3
Dependent Claim
134 words
A circuit for monitoring the current applied to a control mechanism for a fin of a missile from a conductor including: transformer means for magnetically sensing current flow in said conductor, said transformer means including a transformer having a primary winding connected electrically in series with said conductor and a secondary winding; means, including an operational amplifier connected to said secondary winding, for driving said transformer into saturation during a first time interval; biasing means for preventing the introduction of an error signal into said operational amplifier; means for bringing said transformer out of saturation and operating said transformer as a current transformer during a second time interval; and means for providing an output signal, after the initiation of the second time interval, which is proportional to the flow of current in said conductor.
Claim 4
Dependent Claim
134 words
A circuit for monitoring the current applied to a control mechanism for a fin of a missile from a conductor including: transformer means for magnetically sensing current flow in said conductor, said transformer means including a transformer having a primary winding connected electrically in series with said conductor and a secondary winding; means, including an operational amplifier connected to said secondary winding, for driving said transformer into saturation during a first time interval; biasing means for preventing the introduction of an error signal into said operational amplifier; means for bringing said transformer out of saturation and operating said transformer as a current transformer during a second time interval; and means for providing an output signal, after the initiation of the second time interval, which is proportional to the flow of current in said conductor.
Claim 5
Independent Claim
111 words
A method for measuring direct and high duty factor current in a conductor including the steps of: a) magnetically sensing current flow in said conductor with a transformer having a primary winding connected electrically in series with said conductor; b) driving said transformer into saturation during a first time interval with an operational amplifier; c) preventing the introduction of an error signal into said operational amplifier; d) bringing said transformer out of saturating and operating said transformer as a current transformer during a second time interval; and e) providing an output signal, after the initiation of the second time interval, which is proportional to the flow of current in said conductor.
Claim 6
Independent Claim
111 words
A method for measuring direct and high duty factor current in a conductor including the steps of: a) magnetically sensing current flow in said conductor with a transformer having a primary winding connected electrically in series with said conductor; b) driving said transformer into saturation during a first time interval with an operational amplifier; c) preventing the introduction of an error signal into said operational amplifier; d) bringing said transformer out of saturating and operating said transformer as a current transformer during a second time interval; and e) providing an output signal, after the initiation of the second time interval, which is proportional to the flow of current in said conductor.
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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) | 1997-03-07 | 1997-09-06 | 1998-03-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-03-07 | 2001-09-06 | 2002-03-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-03-07 | 2005-09-06 | 2006-03-08 | $7700.00 | Window Closed / Lapsed |