US3401332A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic leakage field and eddy current flaw detection system
Assignee: Magnaflux Corp
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Filing: 1963-11-12
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Granted: 1968-09-10
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Expires: 1983-11-12
Abstract
No abstract record available.
Inventors
- 👤 Glenn O Mcclurg
- 👤 Henry N Nerwin
- 👤 Puidak Heino
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 20:09
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/72; G01N27/82; G01N27/90; G01N27/9006
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
176 words
IN A SYSTEM FOR DETECTING FLAWS IN A WORKPIECE HAVING A UNIDIRECTIONAL MAGNETIC FIELD THEREIN, EDDY CURRENT TESTING MEANS ARRANGED TO INDUCE AN AC FIELD IN THE WORKPIECE AND INCLUDING A FIRST SENSING PROBE ADJACENT A PORTION OF THE WORKPIECE TO DETECT THE EFFECTS OF EDDY CURRENTS IN SAID PORTION OF THE WORKPIECE, SAID EDDY CURRENT TESTING MEANS BEING ARRANGED TO PRODUCE A FIRST ELECTRICAL SIGNAL IN RESPONSE TO FLAWS IN SAID PORTION OF THE WORKPIECE, LEAKAGE FIELD TESTING MEANS INCLUDING A SECOND SENSING PROBE DISPOSED CLOSELY ADJACENT SAID PORTION OF THE WORKPIECE TO SIMULTANEOUSLY DETECT CHANGES IN SAID UNIDIRECTIONAL MAGNETIC FIELD ADJACENT SAID PORTION OF THE WORKPIECE AND TO PRODUCE A SECOND ELECTRICAL SIGNAL IN RESPONSE TO FLAW INDUCED LEAKAGE FIELD CHANGES, AND MEANS FOR SIMULTANEOUSLY INDICATING AND COMPARING SAID FIRST AND SECOND ELECTRICAL SIGNALS TO DETERMINE THE LOCATION AND CHARACTERISTICS OF FLAWS IN SAID PORTION OF THE WORKPIECE, SAID FIRST AND SECOND SENSING PROBES COMPRISING FIRST AND SECOND COILS RESPECTIVELY ON A COMMON AXIS GENERALLY TRANSVERSE TO THE ADJACENT SURFACE PORTION OF THE WORKPIECE.
Claim 2
Dependent Claim
176 words
IN A SYSTEM FOR DETECTING FLAWS IN A WORKPIECE HAVING A UNIDIRECTIONAL MAGNETIC FIELD THEREIN, EDDY CURRENT TESTING MEANS ARRANGED TO INDUCE AN AC FIELD IN THE WORKPIECE AND INCLUDING A FIRST SENSING PROBE ADJACENT A PORTION OF THE WORKPIECE TO DETECT THE EFFECTS OF EDDY CURRENTS IN SAID PORTION OF THE WORKPIECE, SAID EDDY CURRENT TESTING MEANS BEING ARRANGED TO PRODUCE A FIRST ELECTRICAL SIGNAL IN RESPONSE TO FLAWS IN SAID PORTION OF THE WORKPIECE, LEAKAGE FIELD TESTING MEANS INCLUDING A SECOND SENSING PROBE DISPOSED CLOSELY ADJACENT SAID PORTION OF THE WORKPIECE TO SIMULTANEOUSLY DETECT CHANGES IN SAID UNIDIRECTIONAL MAGNETIC FIELD ADJACENT SAID PORTION OF THE WORKPIECE AND TO PRODUCE A SECOND ELECTRICAL SIGNAL IN RESPONSE TO FLAW INDUCED LEAKAGE FIELD CHANGES, AND MEANS FOR SIMULTANEOUSLY INDICATING AND COMPARING SAID FIRST AND SECOND ELECTRICAL SIGNALS TO DETERMINE THE LOCATION AND CHARACTERISTICS OF FLAWS IN SAID PORTION OF THE WORKPIECE, SAID FIRST AND SECOND SENSING PROBES COMPRISING FIRST AND SECOND COILS RESPECTIVELY ON A COMMON AXIS GENERALLY TRANSVERSE TO THE ADJACENT SURFACE PORTION OF THE WORKPIECE.
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) | 1971-09-10 | 1972-03-11 | 1972-09-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-09-10 | 1976-03-11 | 1976-09-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-09-10 | 1980-03-11 | 1980-09-10 | $7700.00 | Window Closed / Lapsed |