Patent US3582571A successfully refreshed from Google Patents.
US3582571A
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US
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Multigap magnetic head having gaps disposed at an angle to each other
Assignee: International Business Machines Corp
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Filing: 1968-10-16
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Granted: 1971-06-01
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Expires: 1988-10-16
Abstract
Abstract A single magnetic head has the longitudinal axes of a recordplayback gap and an erase gap disposed at an angle to each other to reduce erase gap pickup interference during playback. The angle is preferably 45*.
Inventors
- 👤 Charles N Sprott
- 👤 Joe A Young
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 08:51
CPC Classifications
G; G11; G11B; G11B23/00; G11B23/0007; G11B5/00; G11B5/127; G11B5/265; G11B5/2651
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
158 words
A single magnetic head having: a first gap for both recording signals on a magnetic recording medium passing said first gap and reproducing signals recorded on the magnetic recording medium for playback; first and second pole pieces cooperating to form said first gap; a second gap for erasing recorded signals from a magnetic recording medium passing said second gap; said second pole piece and a third pole piece cooperating to form said second gap; a record winding; a Playback winding; an erase winding; said first pole piece having said record winding thereon; each of said first and second pole pieces having a portion of said playback winding thereon; said third pole piece having said erase winding thereon; and means to prevent intelligible signals from being picked up from the recording medium through said second gap during playback by disposing said first and second gaps with their longitudinal axes at an angle of at least 5* to each other.
Claim 2
Dependent Claim
158 words
A single magnetic head having: a first gap for both recording signals on a magnetic recording medium passing said first gap and reproducing signals recorded on the magnetic recording medium for playback; first and second pole pieces cooperating to form said first gap; a second gap for erasing recorded signals from a magnetic recording medium passing said second gap; said second pole piece and a third pole piece cooperating to form said second gap; a record winding; a Playback winding; an erase winding; said first pole piece having said record winding thereon; each of said first and second pole pieces having a portion of said playback winding thereon; said third pole piece having said erase winding thereon; and means to prevent intelligible signals from being picked up from the recording medium through said second gap during playback by disposing said first and second gaps with their longitudinal axes at an angle of at least 5* to each other.
Claim 3
Dependent Claim
47 words
The magnetic head according to claim 1 in which: said second gap has a width substantially greater than the width of said first gap; and said first gap has a width smaller than the wave length of the highest frequency signal that it is desired to receive.
Claim 4
Dependent Claim
33 words
The magnetic head according to claim 1 in which one of said first and second gaps has its longitudinal axis disposed substantially perpendicular to the direction of movement of the magnetic recording medium.
Claim 5
Dependent Claim
34 words
The magnetic head according to claim 3 in which the other of said first and second gaps has its longitudinal axis at an angle of 45* to the longitudinal axis of said one gap.
Claim 6
Dependent Claim
28 words
The magnetic head according to claim 1 in which said first gap has its longitudinal axis disposed substantially perpendicular to the direction of movement of the magnetic medium.
Claim 7
Dependent Claim
29 words
The magnetic head according to claim 5 in which said second gap has its longitudinal axis at an angle of 45* to the longitudinal axis of said first gap.
Claim 8
Dependent Claim
47 words
The magnetic head according to claim 6 in which: said second gap has a width substantially greater than the width of said first gap; and said first gap has a width smaller than the wave length of the highest frequency signal that it is desired to receive.
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) | 1974-05-31 | 1974-11-30 | 1975-06-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-05-31 | 1978-11-30 | 1979-06-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-05-31 | 1982-11-30 | 1983-06-01 | $7700.00 | Window Closed / Lapsed |