US4748525A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Probe head for vertical recording
Assignee: Seagate Technology LLC
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Filing: 1987-09-14
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Granted: 1988-05-31
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Expires: 2007-09-14
Abstract
Abstract A probe head for vertical recording includes a U-shaped member partially surrounding the probe and a coil supported by the U-shaped member. When the coil is energized, flux from the probe is focused to the region between the legs of the U-shaped member to greatly increase flux gradient during a write operation.
Inventors
- 👤 Craig M. Perlov
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 23:58
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/1278
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
311 words
A magnetic recording head for vertically recording digital information onto a moving magnetic medium comprising a probe comprising a ferromagnetic metal bar having a lower end; a read/write coil means wrapped around said probe for inducing magnetic flux in said probe to establish a magnetic pole in the lower end of said probe; a substantially U-shaped member having a pair of legs and an upper body portion constructed of metal at least partially surrounding and spaced from said probe, said legs each having a lower end distal said upper body portion, the lower ends of said legs and the lower end of said probe being so disposed and arranged proximate to said moving magnetic medium that the lower end of one of said legs is leading the lower end of said probe and the lower end of the other of said legs is trailing the lower end of said probe in relation to the relative movement of said probe with respect to said medium and at least one of said legs provides an easy magnetic circuit for magnetic flux induced in said probe by said read/write coil means; and a focus coil means wrapped around said upper body portion of said U-shaped member for focusing the magnetic flux induced in said probe by said read/write coil means to a region of the magnetic medium between the lower ends of the legs of said U-shaped member by establishing a magnetic pole in the lowe end of the leg leading said probe which is the same polarity as the magnetic pole established in said probe, said focus coil means establishing a magnetic pole in the lower end of the leg trailing said probe which is the opposite polarity as the magnetic pole established in said probe to thereby provide a magnetic flux return path from the magnetic medium to said probe during recording.
Claim 2
Dependent Claim
311 words
A magnetic recording head for vertically recording digital information onto a moving magnetic medium comprising a probe comprising a ferromagnetic metal bar having a lower end; a read/write coil means wrapped around said probe for inducing magnetic flux in said probe to establish a magnetic pole in the lower end of said probe; a substantially U-shaped member having a pair of legs and an upper body portion constructed of metal at least partially surrounding and spaced from said probe, said legs each having a lower end distal said upper body portion, the lower ends of said legs and the lower end of said probe being so disposed and arranged proximate to said moving magnetic medium that the lower end of one of said legs is leading the lower end of said probe and the lower end of the other of said legs is trailing the lower end of said probe in relation to the relative movement of said probe with respect to said medium and at least one of said legs provides an easy magnetic circuit for magnetic flux induced in said probe by said read/write coil means; and a focus coil means wrapped around said upper body portion of said U-shaped member for focusing the magnetic flux induced in said probe by said read/write coil means to a region of the magnetic medium between the lower ends of the legs of said U-shaped member by establishing a magnetic pole in the lowe end of the leg leading said probe which is the same polarity as the magnetic pole established in said probe, said focus coil means establishing a magnetic pole in the lower end of the leg trailing said probe which is the opposite polarity as the magnetic pole established in said probe to thereby provide a magnetic flux return path from the magnetic medium to said probe during recording.
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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) | 1991-05-31 | 1991-11-30 | 1992-05-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-05-31 | 1995-11-30 | 1996-05-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-05-31 | 1999-11-30 | 2000-05-31 | $7700.00 | Window Closed / Lapsed |