US3686563A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus utilizing an air core transformer for determining magnetic material content of a substance
Assignee: Kennecott Corp
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Filing: 1970-12-31
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Granted: 1972-08-22
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Expires: 1990-12-31
Abstract
Abstract An air-core transformer is adapted to receive a sample of the substance to be tested for content of magnetic material, e.g., the mineral magnetite. It is supplied, usually through loadisolating means, with constant voltage, high frequency, A.C. power from a square wave generator or the like, preferably a multi-vibrator receiving voltage-regulated D.C. power from a suitable power supply. The resulting high frequency A.C. signal is detected by passage through rectifying and filtering means to yield a corresponding D.C. signal, which is fed to amplifying means that includes means for compensating for non-linearity of the signal. The compensated and amplified D.C. signal is zero controlled and fed to read-out means, such as a meter, through suitable range control means.
Inventors
- 👤 Kenneth E Walter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 03:39
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/72
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
117 words
Apparatus for determining the magnetic material content of a substance, comprising: an air-core transformer adapted to receive, in its core, a sample of the said substance; a constant voltage D.C. power supply for the apparatus; square wave generator means and means for differentiating the generated square wave interconnected between said power supply and said transformer for converting D.C. power to high frequency A.C. power for the transformer; detector means for rectifying and filtering A.C. signals from the transformer to produce corresponding D.C. signal output; means for amplifying said D.C. signal output, including means for compensating for nonlinearity of the signal; zero control means for the amplified signal; and readout means controlled by the amplified and zero-controlled signal.
Claim 2
Dependent Claim
117 words
Apparatus for determining the magnetic material content of a substance, comprising: an air-core transformer adapted to receive, in its core, a sample of the said substance; a constant voltage D.C. power supply for the apparatus; square wave generator means and means for differentiating the generated square wave interconnected between said power supply and said transformer for converting D.C. power to high frequency A.C. power for the transformer; detector means for rectifying and filtering A.C. signals from the transformer to produce corresponding D.C. signal output; means for amplifying said D.C. signal output, including means for compensating for nonlinearity of the signal; zero control means for the amplified signal; and readout means controlled by the amplified and zero-controlled signal.
Claim 3
Dependent Claim
15 words
Apparatus in accordance with claim 1, additionally including range control means for said readout means.
Claim 4
Dependent Claim
35 words
Apparatus in accordance with claim 2, wherein the readout means is a sensitive microammeter and the range control means comprises a plurality of sets of resistors and switches, said sets being interconnected in electrical parallel.
Claim 5
Dependent Claim
41 words
Apparatus in accordance with claim 1, additionally including means for isolating the transformer load from the oscillator, resulting in a constant voltage A.C. signal output independent of the magnetic content of the sample in all instances of use of the apparatus.
Claim 6
Dependent Claim
27 words
Apparatus in accordance with claim 4, wherein the load isolation means comprises solid state circuitry including a transistor and resistors connected to function as an emitter follower.
References Cited (Backward Citations)
US3432747A
Cited
US3535619A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-08-22 | 1976-02-21 | 1976-08-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-22 | 1980-02-21 | 1980-08-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-22 | 1984-02-21 | 1984-08-22 | $7700.00 | Window Closed / Lapsed |