US4698708A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Device for magnetically reading and writing on a flying support
Assignee: Commissariat à l'Énergie Atomique et Aux Énergies Alternatives
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Filing: 1985-01-30
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Granted: 1987-10-06
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Expires: 2005-01-30
Abstract
Abstract Device for reading and writing on a magnetic recording support. The device comprises magnetic read and write heads located on the upper faces of reliefs forming a catamaran, each head having a coil in a plane parallel to said face and having at least one read and write pole piece flush with the upper face of the reliefs. Application to magnetic disks in computers.
Inventors
- 👤 Jean-Pierre Lazzari
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 02:52
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/187; G11B5/1871; G11B5/31; G11B5/3103; G11B5/3163; G11B5/48; G11B5/58; G11B5/60; G11B5/6005
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
192 words
A device for reading and writing on a magnetic recording support, comprising: a monocrystalline silicon wafer having 100 and 111 crystal planes, said wafer having a bottom face parallel to 100 crystal planes and an upper face parallel to said bottom face, said wafer having its bottom face etched to comprise two sliders forming a catamaran-type profile, each slider having a bottom surface corresponding to said 100 crystal planes and two sides inclined in accordance with said 111 crystal planes, a magnetic read and write head being arranged on said bottom surface of each slider at one end thereof, each head having a coil in a plane parallel to said bottom surface and having at least one read and write pole, pyramidal holes having walls parallel to 111 crystal planes, said holes completely traversing said silicon wafer from said upper face down to said bottom face, said walls being covered with a first metal coating, a second metal coating being deposited on said bottom face in contact with said first metal coating and with said coil to provide for electrical connections along said metal coatings between said coils and an external circuit.
Claim 2
Independent Claim
192 words
A device for reading and writing on a magnetic recording support, comprising: a monocrystalline silicon wafer having 100 and 111 crystal planes, said wafer having a bottom face parallel to 100 crystal planes and an upper face parallel to said bottom face, said wafer having its bottom face etched to comprise two sliders forming a catamaran-type profile, each slider having a bottom surface corresponding to said 100 crystal planes and two sides inclined in accordance with said 111 crystal planes, a magnetic read and write head being arranged on said bottom surface of each slider at one end thereof, each head having a coil in a plane parallel to said bottom surface and having at least one read and write pole, pyramidal holes having walls parallel to 111 crystal planes, said holes completely traversing said silicon wafer from said upper face down to said bottom face, said walls being covered with a first metal coating, a second metal coating being deposited on said bottom face in contact with said first metal coating and with said coil to provide for electrical connections along said metal coatings between said coils and an external circuit.
Claim 3
Dependent Claim
39 words
A device according to claim 1, wherein it also comprises on said upper face of the silicon wafer, a blind pyramidal hole with inclined walls in accordance with 111 crystal planes, a holding pivot being fixed within said hole.
Claim 4
Dependent Claim
21 words
A device according to claim 1, wherein the read and write head comprises two pole pieces separated by a non-magnetic wall.
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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) | 1990-10-05 | 1991-04-06 | 1991-10-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-10-05 | 1995-04-06 | 1995-10-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-10-05 | 1999-04-06 | 1999-10-06 | $7700.00 | Window Closed / Lapsed |