Patent US4500838A successfully refreshed from Google Patents.
US4500838A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Current sensor
Assignee: General Electric Co
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Filing: 1983-01-24
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Granted: 1985-02-19
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Expires: 2003-01-24
Abstract
Abstract A current sensor, responsive to the first power of a current to be measured, utilizes a piezoelectric element located between a current-carrying conductor and a permanent magnet having its north-south poles aligned normal to the direction of current flow through the conductor. The substantially constant magnetic field provides a sensor output, taken from electrodes upon opposite surfaces of the piezoelectric member, which is proportional to the first power of current flowing in the single conductor.
Inventors
- 👤 Milton D. Bloomer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 12:56
CPC Classifications
G; G01; G01R; G01R33/00; G01R33/02; G01R33/038; G01R15/00; G01R15/14; G01R15/146; G01R15/148
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
97 words
A sensor.having an output responsive to the first power of a sensed current, comprising: a piezoelectric element having first and second opposed surfaces; first and second electrodes fabricated upon said piezoelectric element first and second surfaces, said sensor output being provided between said first and second electrodes; conductor means positioned adjacent to one piezoelectric element surface for carrying a current to be measured therepast; and a permanent magnet member positioned adjacent to the remaining surface of the piezoelectric element and having the north-south poles thereof aligned normal to the direction of current flow in said conductor means.
Claim 2
Dependent Claim
97 words
A sensor.having an output responsive to the first power of a sensed current, comprising: a piezoelectric element having first and second opposed surfaces; first and second electrodes fabricated upon said piezoelectric element first and second surfaces, said sensor output being provided between said first and second electrodes; conductor means positioned adjacent to one piezoelectric element surface for carrying a current to be measured therepast; and a permanent magnet member positioned adjacent to the remaining surface of the piezoelectric element and having the north-south poles thereof aligned normal to the direction of current flow in said conductor means.
Claim 3
Dependent Claim
24 words
The sensor of claim 1, further comprising a layer of insulative material interposed between said conductor and the electrode-bearing piezoelectric element surface closest thereto.
Claim 4
Dependent Claim
14 words
The sensor of claim 2, wherein said insulative layer is a substantially rigid substrate.
Claim 5
Dependent Claim
21 words
The sensor of claim 2, further comprising a substrate supporting said conductor upon the opposite side thereof from said piezoelectric element.
Claim 6
Dependent Claim
17 words
The sensor of claim 4, wherein said substrate is positioned between said insulative layer and said conductor.
Claim 7
Dependent Claim
22 words
The sensor of claim 1, further comprising an insulative substrate interposed between said conductor and the electrode-bearing piezoelectric element surface closest thereto.
Claim 8
Dependent Claim
11 words
The sensor of claim 6, wherein said substrate is substantially rigid.
Claim 9
Dependent Claim
26 words
The sensor of claim 1, further comprising cover means at least adjacent to said magnet member for protectively enclosing at least a portion of said sensor.
Claim 10
Dependent Claim
17 words
The sensor of claim 1, wherein said electrodes are substantially planar and substantially parallel to one another.
Claim 11
Dependent Claim
27 words
The sensor of claim 9, wherein said conductor means is a conductive member having a substantially planar surface substantially parallel to the plane of the adjacent electrode.
Claim 12
Dependent Claim
20 words
The sensor of claim 10, wherein said magnet member provides a substantially constant magnetic field substantially parallel to said electrodes.
Claim 13
Dependent Claim
18 words
The sensor of claim 1, further comprising lead means connected to said electrodes for providing the sensor output.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-02-19 | 1988-08-20 | 1989-02-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-02-19 | 1992-08-20 | 1993-02-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-02-19 | 1996-08-20 | 1997-02-19 | $7700.00 | Window Closed / Lapsed |