Patent US4935832A successfully refreshed from Google Patents.
US4935832A
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Recording heads with side shields
Assignee: PHC Corp
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Filing: 1988-03-16
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Granted: 1990-06-19
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Expires: 2008-03-16
Abstract
Abstract Side shields are provided adjacent to the magnetic poles of recording heads. The side shields are used for read and write operations for both longitudinal and vertical recording. During read, the side shields intercept flux from adjacent tracks and shunts it around the sensor to magnetic ground. During write, side shields contain the write field of the head so that it does not corrupt the data on adjacent tracks. Embodiments are disclosed for both longitudinal and perpendicular or vertical recording.
Inventors
- 👤 Shyam C. Das
- 👤 Michael L. Mallary
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 10:34
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/31; G11B5/3109; G11B5/313; G11B5/3143; G11B5/3146; G11B5/315; G11B5/10; G11B5/11; G11B5/1278; G11B5/187; G11B5/3116; G11B5/33; G11B5/39; G11B5/3903; G11B5/3906; G11B5/3916; G11B5/3919; G11B5/3922; G11B5/3925; G11B5/3945; G11B5/3948; G11B5/3951; G11B5/3954; G11B5/398; G11B2005/0002; G11B2005/0005; G11B2005/0008; G11B5/02; G11B5/09
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
101 words
A recording head comprising: a center magnetic pole and two outer magnetic poles which are coupled in a yoke region in one end of the head and are respectively separated by longitudinally extending gaps as the poles extend longitudinally from the yoke region, the poles terminating at a tip region of the head, this tip region configured to operate generally parallel to the surface of a recording medium; and at least one magnetic side shield for shielding the center pole disposed adjacent to the center pole, the side shield extending from one of the outer poles generally perpendicularly to the gaps.
Claim 2
Dependent Claim
101 words
A recording head comprising: a center magnetic pole and two outer magnetic poles which are coupled in a yoke region in one end of the head and are respectively separated by longitudinally extending gaps as the poles extend longitudinally from the yoke region, the poles terminating at a tip region of the head, this tip region configured to operate generally parallel to the surface of a recording medium; and at least one magnetic side shield for shielding the center pole disposed adjacent to the center pole, the side shield extending from one of the outer poles generally perpendicularly to the gaps.
Claim 3
Dependent Claim
17 words
The recording head of claim 1 wherein the magnetic side shield is made of magnetically soft material.
Claim 4
Dependent Claim
23 words
The recording head of claim 1 wherein the side shield is substantially non-saturable with respect to the pole tips in the read mode.
Claim 5
Dependent Claim
33 words
The recording head of claim 1 wherein said region defines an air bearing surface of the head and the poles appear asymmetrical when looking through the air bearing surface from the medium location.
Claim 6
Dependent Claim
15 words
The recording head of claim 1 wherein the magnetic side shield is made of NiFe.
Claim 7
Dependent Claim
30 words
The recording head of claim 1 wherein the side shield is an intimate component of one of the outer poles such that the shield is inherently grounded to that pole.
Claim 8
Dependent Claim
19 words
The recording head of claim 6 wherein the inherently grounded side shield does not extend over the entire pole.
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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) | 1993-06-18 | 1993-12-18 | 1994-06-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-06-18 | 1997-12-18 | 1998-06-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-06-18 | 2001-12-18 | 2002-06-19 | $7700.00 | Window Closed / Lapsed |