US3629741A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Transformer with controlled low coupling
Assignee: AT&T Inc
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Filing: 1969-05-29
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Granted: 1971-12-21
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Expires: 1989-05-29
Abstract
Abstract A transformer having controlled low coupling between its windings. The transformer comprises a unitary core of ferromagnetic material, such as ferrite or carbonyl iron, fabricated in one piece with first and second pairs of apertures formed therein. A primary winding is threaded through the first pair of apertures and a secondary winding is threaded through the second pair of apertures. The coupling between these windings is controlled by means including a portion of the unitary core which is located between the two pairs of apertures. This provides completely closed magnetic paths in the core material for all the magnetic flux produced by driving either the primary or secondary windings.
Inventors
- 👤 William L Brune
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 12:52
CPC Classifications
H; H01; H01F; H01F38/00; H01F38/08; H01F29/00; H01F29/14; H01F29/143
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
278 words
An inductive device comprising a transformer having primary and secondary windings with controlled low coupling between said windings and adapted for functioning in the equivalent manner of a transmission network having a pi configuration of two shunt inductances bridged by a series inductance, said device comprising a flat unitary core of magnetically soft material having means defining a plurality of holes therein, a primary winding of electrically conductive wire threaded through a first pair of said holes, a secondary winding of electrically conductive wire threaded through a second pair of said holes, said primary and secondary windings being adapted for producing the effect of said two shunt inductances of said pi configuration, means for electrically energizing said primary winding for creating a magnetic flux in said core, a first portion of said magnetic flux being adapted to flow in said core in the immediate area therein around said first pair of holes, coupling means for providing at least one closed path between said primary and secondary windings for the flow therein of a second portion of said magnetic flux from said primary winding to said secondary winding, said coupling means includinG an integral portion of said unitary core that is positioned between said first and second pairs of holes, said integral core portion being so constructed and fabricated as to provide said controlled low coupling between said primary and secondary windings, and said integral core portion being adapted for producing the effect of said series inductance of said pi configuration. said coupling means including a portion of said core that is positioned between said first and second pairs of holes, and said core portion constituting said series inductance.
Claim 2
Dependent Claim
278 words
An inductive device comprising a transformer having primary and secondary windings with controlled low coupling between said windings and adapted for functioning in the equivalent manner of a transmission network having a pi configuration of two shunt inductances bridged by a series inductance, said device comprising a flat unitary core of magnetically soft material having means defining a plurality of holes therein, a primary winding of electrically conductive wire threaded through a first pair of said holes, a secondary winding of electrically conductive wire threaded through a second pair of said holes, said primary and secondary windings being adapted for producing the effect of said two shunt inductances of said pi configuration, means for electrically energizing said primary winding for creating a magnetic flux in said core, a first portion of said magnetic flux being adapted to flow in said core in the immediate area therein around said first pair of holes, coupling means for providing at least one closed path between said primary and secondary windings for the flow therein of a second portion of said magnetic flux from said primary winding to said secondary winding, said coupling means includinG an integral portion of said unitary core that is positioned between said first and second pairs of holes, said integral core portion being so constructed and fabricated as to provide said controlled low coupling between said primary and secondary windings, and said integral core portion being adapted for producing the effect of said series inductance of said pi configuration. said coupling means including a portion of said core that is positioned between said first and second pairs of holes, and said core portion constituting said series inductance.
Claim 3
Dependent Claim
196 words
An inductive device having a substantial degree of frequency selectivity, said device comprising a disk of magnetically soft material having means defining a plurality of holes therein, a first winding of electrically conductive wire threaded through a first hole and a second hole, a second winding of electrically conductive wire threaded through a third hole and a fourth hole, means for tuning said first and second windings to a first frequency, means for electrically energizing said first winding for creating a magnetic flux in said disk, coupling means for electrically coupling said first winding to said second winding, said coupling means comprising means for providing a closed path for the flow of said flux from said first winding to said second winding, said last-mentioned means including a portion of said disk that is located between said four holes, and instrumentalities for increasing the degree of said coupling, said instrumentalities including a third winding of electrically conductive wire threaded through said first hole and said third hole, a fourth winding of electrically conductive wire threaded through said second hole and said fourth hole, and means for turning both said third and fourth windings to a second frequency.
Claim 4
Dependent Claim
196 words
An inductive device having a substantial degree of frequency selectivity, said device comprising a disk of magnetically soft material having means defining a plurality of holes therein, a first winding of electrically conductive wire threaded through a first hole and a second hole, a second winding of electrically conductive wire threaded through a third hole and a fourth hole, means for tuning said first and second windings to a first frequency, means for electrically energizing said first winding for creating a magnetic flux in said disk, coupling means for electrically coupling said first winding to said second winding, said coupling means comprising means for providing a closed path for the flow of said flux from said first winding to said second winding, said last-mentioned means including a portion of said disk that is located between said four holes, and instrumentalities for increasing the degree of said coupling, said instrumentalities including a third winding of electrically conductive wire threaded through said first hole and said third hole, a fourth winding of electrically conductive wire threaded through said second hole and said fourth hole, and means for turning both said third and fourth windings to a second frequency.
Claim 5
Dependent Claim
211 words
An inductive device for functioning in the manner of a narrow band-pass filter, said device comprising a flat core of magnetically soft material having means defining first and second pairs of holes therein, a first winding of electrically conductive wire threaded through said first pair of holes, a second winding of electrically conductive wire threaded through said second pair of holes, means for electrically energizing said first winding for creating a magnetic flux in said core, coupling means for electrically coupling said first winding to said second winding, said coupling means comprising means for providing a closed path for the flow of said flux from said first winding to said second winding, said last-mentioned means including a portion of said core that is located between said first and second pairs of holes, and instrumentalities for blocking the flow of flux in said portion of said core for energy of a particular frequency, said instrumentalities comprising means defining a third pair of holes in said core, said third pair of holes being located in said portion of said core between said first and second pairs of holes, a third winding of electrically conductive wire threaded through said third pair of holes, and means for tuning said third winding to said particular frequency.
Claim 6
Dependent Claim
211 words
An inductive device for functioning in the manner of a narrow band-pass filter, said device comprising a flat core of magnetically soft material having means defining first and second pairs of holes therein, a first winding of electrically conductive wire threaded through said first pair of holes, a second winding of electrically conductive wire threaded through said second pair of holes, means for electrically energizing said first winding for creating a magnetic flux in said core, coupling means for electrically coupling said first winding to said second winding, said coupling means comprising means for providing a closed path for the flow of said flux from said first winding to said second winding, said last-mentioned means including a portion of said core that is located between said first and second pairs of holes, and instrumentalities for blocking the flow of flux in said portion of said core for energy of a particular frequency, said instrumentalities comprising means defining a third pair of holes in said core, said third pair of holes being located in said portion of said core between said first and second pairs of holes, a third winding of electrically conductive wire threaded through said third pair of holes, and means for tuning said third winding to said particular frequency.
Claim 7
Dependent Claim
237 words
An inductive device for functioning in the manner of a separation filter, said device comprising a disk of magnetically soft material having means defining three pairs of holes therein, a first winding of electrically conductive wire threaded through a first pair of said holes, a second winding of electrically conductive wire threaded through a second pair of said holes, a third winding of electrically conductive wire threaded through a third pair of said holes, means for electrically energizing said first winding for creating a magnetic flux in said disk, first coupling means for providing a closed path for the flow of said flux from said first winding to said second winding, said first coupling means including a fiRst portion of said disk that is located between said first and second pairs of holes, second coupling means for providing a closed path for the flow of said flux from said first winding to said third winding, said second coupling means including a second portion of said disk that is located between said first and third pairs of holes, means for tuning said second winding to a first frequency, means for tuning said third winding to a second frequency, and means for preventing the flow of said flux between said second and third windings, said last-mentioned means including means defining a wedge-shaped opening formed in said disk between said second pair of holes and said third pair of holes.
Claim 8
Dependent Claim
237 words
An inductive device for functioning in the manner of a separation filter, said device comprising a disk of magnetically soft material having means defining three pairs of holes therein, a first winding of electrically conductive wire threaded through a first pair of said holes, a second winding of electrically conductive wire threaded through a second pair of said holes, a third winding of electrically conductive wire threaded through a third pair of said holes, means for electrically energizing said first winding for creating a magnetic flux in said disk, first coupling means for providing a closed path for the flow of said flux from said first winding to said second winding, said first coupling means including a fiRst portion of said disk that is located between said first and second pairs of holes, second coupling means for providing a closed path for the flow of said flux from said first winding to said third winding, said second coupling means including a second portion of said disk that is located between said first and third pairs of holes, means for tuning said second winding to a first frequency, means for tuning said third winding to a second frequency, and means for preventing the flow of said flux between said second and third windings, said last-mentioned means including means defining a wedge-shaped opening formed in said disk between said second pair of holes and said third pair of holes.
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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) | 1974-12-20 | 1975-06-21 | 1975-12-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-12-20 | 1979-06-21 | 1979-12-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-12-20 | 1983-06-21 | 1983-12-21 | $7700.00 | Window Closed / Lapsed |