US4897747A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Write/read head including monocrystalline magnetic thin films protected by a coating having hardened and lubricating zones
Assignee: Thales SA
•
Filing: 1988-03-04
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Granted: 1990-01-30
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Expires: 2008-03-04
Abstract
Abstract In a method for making a thin-film magnetic head, there are stages for depositing hardening material in the plane of the magnetic films and in the neighbourhood of the active surface of the magnetic head. The invention also relates to a magnetic head made according to this method. The invention can be applied to thin-film magnetic heads for magnetic tape read/write devices.
Inventors
- 👤 Paul-Louis Meunier
- 👤 Manijeh Razeghi
- 👤 Jean-Luc Rolland
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 14:14
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/31; G11B5/187; G11B5/23; G11B5/235; G11B5/3103; G11B5/3106; G11B5/3109; G11B5/313; G11B5/3133; G11B5/3163; G11B5/3176; G11B5/3179; G11B5/3183
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
114 words
A read/write thin-film magnetic head comprising the following, deposited successively on a substrate: a first monocrystalline film of a magnetic material, a film of a non-magnetic material, a second monocrystalline film of a magnetic material, said magnetic head having a side with which the various films are flush, said side forming an active write surface against which moves a magnetic writing medium, wherein the active write surface is coated with at least one film of a material having hardened zones and lubricating zones stacked in two dimensions or three dimensions, wherein said lubricating zones have a lower coefficient of friction than said hardened zones and said hardened zones increase the head's resistance to wear.
Claim 2
Dependent Claim
114 words
A read/write thin-film magnetic head comprising the following, deposited successively on a substrate: a first monocrystalline film of a magnetic material, a film of a non-magnetic material, a second monocrystalline film of a magnetic material, said magnetic head having a side with which the various films are flush, said side forming an active write surface against which moves a magnetic writing medium, wherein the active write surface is coated with at least one film of a material having hardened zones and lubricating zones stacked in two dimensions or three dimensions, wherein said lubricating zones have a lower coefficient of friction than said hardened zones and said hardened zones increase the head's resistance to wear.
Claim 3
Dependent Claim
33 words
A read/write thin-film magnetic head according to claim 1, wherein the at least one film coated on the active writing surface is made up of alternative stacks of hardened zones and lubricating zones.
References Cited (Backward Citations)
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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) | 1993-01-29 | 1993-07-31 | 1994-01-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-01-29 | 1997-07-31 | 1998-01-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-01-29 | 2001-07-31 | 2002-01-30 | $7700.00 | Window Closed / Lapsed |