US3984874A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High density magnetic recording and reproducing system
Assignee: TDK ELECTRONIC Co
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Filing: 1974-11-18
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Granted: 1976-10-05
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Expires: 1994-11-18
Abstract
Abstract A magnetic recording and reproducing system having a magnetic head wherein a thickness of an edge of a head gap of a head core is smaller than a width of the head gap, and means for recording and reproducing a magnetic recording medium by the magnetic head in a direction of magnetization which is a perpendicular or slant direction to the direction of movement of the magnetic recording medium.
Inventors
- 👤 Yujiro Mano
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 23:32
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/187; G11B5/23; G11B5/02; G11B5/48; G11B5/488; G11B2005/0002
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
158 words
A magnetic recording and reproducing system comprising: a magnetic tape, a magnetic head disposed adjacent to the magnetic tape and being separated from the magnetic tape by a distance l', the magnetic head comprising: a magnetic core having a gap g' therein, the gap being disposed adjacent to the magnetic tape, a coil wrapped about the magnetic core, the magnetic core having two edges which define the gap, each edge having a thickness w', the magnetic head being disposed with respect to the magnetic tape so that a line joining the two edges of the magnetic core which define the gap intersects at a substantial angle a line defining the direction of movement of the magnetic tape, w' being equal to 0.5-5 μm, g' being equal to 0.1 - 10 μm, w' divided by g' being equal to 0.05 - 0.5, l' being less than 0.3 μm and w' divided by l' being equal to 1.7 - 17.
Claim 2
Dependent Claim
158 words
A magnetic recording and reproducing system comprising: a magnetic tape, a magnetic head disposed adjacent to the magnetic tape and being separated from the magnetic tape by a distance l', the magnetic head comprising: a magnetic core having a gap g' therein, the gap being disposed adjacent to the magnetic tape, a coil wrapped about the magnetic core, the magnetic core having two edges which define the gap, each edge having a thickness w', the magnetic head being disposed with respect to the magnetic tape so that a line joining the two edges of the magnetic core which define the gap intersects at a substantial angle a line defining the direction of movement of the magnetic tape, w' being equal to 0.5-5 μm, g' being equal to 0.1 - 10 μm, w' divided by g' being equal to 0.05 - 0.5, l' being less than 0.3 μm and w' divided by l' being equal to 1.7 - 17.
Claim 3
Dependent Claim
55 words
A magnetic recording and reproducing system in accordance with claim 1, wherein the magnetic head is disposed with respect to the magnetic tape so that a line joining the two edges of the magnetic core which define the gap intersects at a 90° angle a line defining the direction of movement of the magnetic tape.
Claim 4
Dependent Claim
55 words
A magnetic recording and reproducing system in accordance with claim 1, wherein the magnetic head is disposed with respect to the magnetic tape so that a line joining the two edges of the magnetic core which define the gap intersects at a 45° angle a line defining the direction of movement of the magnetic tape.
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) | 1979-10-05 | 1980-04-05 | 1980-10-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-10-05 | 1984-04-05 | 1984-10-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-10-05 | 1988-04-05 | 1988-10-05 | $7700.00 | Window Closed / Lapsed |