US3855530A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic metal defect-detecting apparatus
Assignee: JFE Engineering Corp
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Filing: 1973-09-17
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Granted: 1974-12-17
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Expires: 1993-09-17
Abstract
Abstract A magnetic metal defect-detecting apparatus comprising a crossshaped magnetic core assembly prepared from two pairs of magnetic pole members providing two pairs of magnetic poles intersecting each other at right angles and each fitted with a caster at the end; a first and a second coil wound about the two pairs of magnetic pole members; and a power supply device for supplying the first coil with single phase alternating current of positive half wave and the second coil with single phase alternating current of negative half wave, thereby alternately applying each of two magnetic fluxes in perpendicularly intersecting directions.
Inventors
- 👤 T Fuji
- 👤 Y Otsuka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 15:55
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/72; G01N27/82; G01N27/83; G01N27/84
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
168 words
A magnetic metal defect-detecting apparatus comprising: a cross-shaped magnetic core assembly including two pairs of magnetic pole members providing two pairs of magnetic poles intersecting each other; a first and a second coil wound about the two pairs of magnetic pole members; a power supply device including a source of single phase alternating current; at least one first rectifier connected in series between the source of single phase alternating current and the first coil in the forward direction with respect to the positive half wave of the single phase alternating current for supplying the first coil with single phase alternating current of positive half wave; and at least one second rectifier connected in series between the source of single phase alternating current and the second coil in the forward direction with respect to the negative half wave of the single phase alternating current for supplying the second coil with single phase alternating current of negative half wave; thereby alternately applying each of two magnetic fluxes in intersecting directions.
Claim 2
Dependent Claim
168 words
A magnetic metal defect-detecting apparatus comprising: a cross-shaped magnetic core assembly including two pairs of magnetic pole members providing two pairs of magnetic poles intersecting each other; a first and a second coil wound about the two pairs of magnetic pole members; a power supply device including a source of single phase alternating current; at least one first rectifier connected in series between the source of single phase alternating current and the first coil in the forward direction with respect to the positive half wave of the single phase alternating current for supplying the first coil with single phase alternating current of positive half wave; and at least one second rectifier connected in series between the source of single phase alternating current and the second coil in the forward direction with respect to the negative half wave of the single phase alternating current for supplying the second coil with single phase alternating current of negative half wave; thereby alternately applying each of two magnetic fluxes in intersecting directions.
Claim 3
Dependent Claim
32 words
A detecting apparatus accOrding to claim 1 wherein the cross-shaped magnetic core assembly comprises two pairs of magnetic pole members, each of which is fitted with a caster at the end thereof.
Claim 4
Dependent Claim
102 words
A detecting apparatus according to claim 2 wherein the cross-shaped magnetic core assembly comprises a first laminated core section bent substantially at right angles; a second laminated core section bent substantially at right angles and so positioned relative to the first laminated core section as to cause the outside of the bent portion to abut against that of the bent portion of the first laminated core section; a joining means for assembling the mutually abutting bent portions of the first and second laminated core sections into a cross-shaped magnetic core; and a handle attached to the magnetic core by the joining means.
Claim 5
Dependent Claim
35 words
A detecting apparatus according to claim 1 wherein the respective ends of the two pairs of magnetic pole members are located so as to substantially contact the surface of a test piece of metal material.
Claim 6
Dependent Claim
42 words
A detecting apparatus according to claim 1 wherein the respective ends of the two pairs of magnetic pole members are located so as to contact the inner surfaces of two test pieces of metal material joined on the edge at right angles.
Claim 7
Dependent Claim
110 words
A detecting apparatus according to claim 1 wherein the first and second coils are connected together at one end, and including: a first rectifier and a second rectifier, the first and second rectifiers having cathodes which are connected to respective corresponding terminals of said single phase alternating current source and anodes which are connected together; and a variable resistor which is connected between the junction of the anodes of the first and second rectifiers and the junction of the connected together ends of the first and second coils; the other ends of the first and second coils being connected to said corresponding terminals of said single phase alternating current source.
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) | 1977-12-16 | 1978-06-17 | 1978-12-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-16 | 1982-06-17 | 1982-12-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-16 | 1986-06-17 | 1986-12-17 | $7700.00 | Window Closed / Lapsed |