Patent US3737583A successfully refreshed from Google Patents.
US3737583A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic head with wear-resistant surface, and methods of producing the same
Assignee: Sony Corp
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Filing: 1971-03-16
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Granted: 1973-06-05
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Expires: 1991-03-16
Abstract
Abstract A magnetic head core element, for example, of ferrite, is provided, at least at a surface thereof subject to wear, with an electrodeposited magnetic metal layer containing a dispersed powder that is harder than the metal. The powder-containing metal layer is electrodeposited by immersing the core, preferably after deoxidizing the surface thereof to receive the layer, in an electrolyte containing a salt of the magnetic metal and a dispersion of the relatively hard powder, and passing a current between the core, acting as a cathode, and an anode also immersed in the electrolyte.
Inventors
- 👤 N Tsuchiya
- 👤 K Amari
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 19:59
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/187; G11B5/21; G11B5/255
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
27 words
A magnetic head according to claim 1, in which an electrodeposited magnetic metal layer of high permeability underlies said layer constituting the wear-resistant surface of the core.
Claim 2
Dependent Claim
30 words
A magnetic head according to claim 2, in which said layer of high permeability is of the same iron-nickel alloy as is included in said layer constituting the wear-resistant surface.
Claim 3
Dependent Claim
13 words
A magnetic head according to claim 1, in which said powder is magnetic.
Claim 4
Dependent Claim
14 words
A magnetic head according to claim 4, in which said magnetic powder is ferrite.
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) | 1976-06-04 | 1976-12-04 | 1977-06-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-06-04 | 1980-12-04 | 1981-06-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-06-04 | 1984-12-04 | 1985-06-05 | $7700.00 | Window Closed / Lapsed |