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Patent US3143690A successfully refreshed from Google Patents.
US3143690A
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Electromagnetic pinch roller actuator
Assignee: Ampex Corp
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Filing: 1962-01-25
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Granted: 1964-08-04
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Expires: 1982-01-25
Abstract
No abstract record available.
Inventors
- 👤 Arthur E Young
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 10:38
CPC Classifications
H; H01; H01F; H01F7/00; H01F7/02; H01F7/04; G; G11; G11B; G11B15/00; G11B15/02; G11B15/10; G11B15/18; G11B15/22; G11B15/26; G11B15/28; G11B15/29; H01F7/06; H01F7/08; H01F7/14
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
131 words
AN ELECTROMAGNETIC ACTUATOR SUITABLE FOR HIGH SPEED MOVEMENT OF A PINCH ROLLER IN A MAGNETIC TAPE TRANSPORT, COMPRISING: A SYMMETRICAL MAGNETIC CORE STRUCTURE INCLUDING TWO HALVES EACH HAVING A NUMBER OF LEGS, THE LEGS OF THE TWO HALVES BEING IN OPPOSED FACING RELATION; PERMANENT MAGNET MEANS POSITIONED BETWEEN A PAIR OF THE OPPOSED LEGS AND ESTABLISHING A PARTICULAR MAGNETIC FLUX PATTERN IN THE CORE STRUCTURE; ARMATURE MEANS ROTATABLE ABOUT A SELECTED AXIS BETWEEN TWO OTHER OPPOSED PAIRS OF LEGS OF THE TWO HALVES, THE ARMATURE MEANS NORMALLY BEING EQUIDISTANT FROM EACH OF THE OPPOSED LEGS; AND MEANS ADJACENT TO BUT ONE SELECTED LEG OF SAID TWO OTHER PAIRS FOR INCREASING THE FLUX DENSITY IN SAID SELECTED LEG, THEREBY MODIFYING THE FLUX PATTERN IN THE CORE STRUCTURE, THEREBY TO ROTATE THE ARMATURE.
Claim 2
Dependent Claim
131 words
AN ELECTROMAGNETIC ACTUATOR SUITABLE FOR HIGH SPEED MOVEMENT OF A PINCH ROLLER IN A MAGNETIC TAPE TRANSPORT, COMPRISING: A SYMMETRICAL MAGNETIC CORE STRUCTURE INCLUDING TWO HALVES EACH HAVING A NUMBER OF LEGS, THE LEGS OF THE TWO HALVES BEING IN OPPOSED FACING RELATION; PERMANENT MAGNET MEANS POSITIONED BETWEEN A PAIR OF THE OPPOSED LEGS AND ESTABLISHING A PARTICULAR MAGNETIC FLUX PATTERN IN THE CORE STRUCTURE; ARMATURE MEANS ROTATABLE ABOUT A SELECTED AXIS BETWEEN TWO OTHER OPPOSED PAIRS OF LEGS OF THE TWO HALVES, THE ARMATURE MEANS NORMALLY BEING EQUIDISTANT FROM EACH OF THE OPPOSED LEGS; AND MEANS ADJACENT TO BUT ONE SELECTED LEG OF SAID TWO OTHER PAIRS FOR INCREASING THE FLUX DENSITY IN SAID SELECTED LEG, THEREBY MODIFYING THE FLUX PATTERN IN THE CORE STRUCTURE, THEREBY TO ROTATE THE ARMATURE.
References Cited (Backward Citations)
US2930945A
Cited
US3071714A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1967-08-04 | 1968-02-03 | 1968-08-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-08-04 | 1972-02-03 | 1972-08-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-08-04 | 1976-02-03 | 1976-08-04 | $7700.00 | Window Closed / Lapsed |