US3864753A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Transducer head with spacer material made of stainless steel
Assignee: GRESHAM INFOMAG Ltd
•
Filing: 1973-05-09
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Granted: 1975-02-04
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Expires: 1993-05-09
Abstract
Abstract An electromagnetic transducer head comprises a plurality of magnetic tracking circuits with screening means between the individual circuits and in order to overcome the adverse effects of differential wear as between the magnetic circuit pole pieces and the intermediate spacer material used is made of stainless steel in place of the conventional non-magnetic materials such as brass, aluminium and plastics materials. The tracking circuits may be fitted into slots in a stainless steel blank or a blank of conventional non-magnetic material may be used with stainless steel spacers fitted in between the tracking circuits.
Inventors
- 👤 Robert Sidney Becker
- 👤 Eric Frank Painter
- 👤 Gerrard Charles Rickard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 06:35
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/187; G11B5/255; G11B5/29; G11B5/295
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
93 words
A multi-track tape electromagnetic transducer head comprising a body having a surface over which a tape is adapted to pass, a plurality of respective magnetic tracking circuits supported in said body and each having a pole piece having a face flush with and forming part of said surface, each said face contacting a respective longitudinally extending area of said tape for the transfer of information between the associateD magnetic and the associated area of the tape, characterised in that said surface is at least partially of stainless steel between said magnetic tracking circuits.
Claim 2
Dependent Claim
93 words
A multi-track tape electromagnetic transducer head comprising a body having a surface over which a tape is adapted to pass, a plurality of respective magnetic tracking circuits supported in said body and each having a pole piece having a face flush with and forming part of said surface, each said face contacting a respective longitudinally extending area of said tape for the transfer of information between the associateD magnetic and the associated area of the tape, characterised in that said surface is at least partially of stainless steel between said magnetic tracking circuits.
Claim 3
Dependent Claim
114 words
In a multi-track electromagnetic transducer head comprising a body blank having a surface over which a tape is adapted to pass in contact with said surface, a plurality of respective magnetic tracking circuits supported in said blank and each having a pole piece having a face flush with and forming part of said surface, each said face contacting a respective longitudinally extending area of said tape for the transfer of information between the associated magnetic circuit and the associated area of the tape, screening means between the respective tracking circuits, and land areas between the tracking circuits and forming parts of said surface, the improvement comprising said land areas being formed of stainless steel.
Claim 4
Dependent Claim
114 words
In a multi-track electromagnetic transducer head comprising a body blank having a surface over which a tape is adapted to pass in contact with said surface, a plurality of respective magnetic tracking circuits supported in said blank and each having a pole piece having a face flush with and forming part of said surface, each said face contacting a respective longitudinally extending area of said tape for the transfer of information between the associated magnetic circuit and the associated area of the tape, screening means between the respective tracking circuits, and land areas between the tracking circuits and forming parts of said surface, the improvement comprising said land areas being formed of stainless steel.
Claim 5
Dependent Claim
37 words
A transducer head as claimed in claim 2, in which the body blank is of stainless steel and is grooved to receive said tracking circuits and screening means, said land areas comprising parts of said body blank.
Claim 6
Dependent Claim
37 words
A transducer head as claimed in claim 2, in which the body blank is of non-magnetic material and has inserts at least partially of stainless steel fitted therein between the tracking circuits and forming said land areas.
Claim 7
Dependent Claim
39 words
A transducer head as claimed in claim 2, in which the land area between each pair of adjacent tracking circuits is of stainless steel adjacent to each tracking circuit with said screening means substantially midway between the tracking circuits.
Claim 8
Dependent Claim
38 words
A transducer head as claimed in claim 5, wherein the thickness of said screening means transversely of the direction of movement of the tape is substantially equal to the thickness of the stainless steel on each side thereof.
Claim 9
Dependent Claim
53 words
A transducer head as claimed in claim 4, in which each insert comprises a screening plate co-extensive with the adjacent tracking circuits and portions of stainless steel on each side of the screening plate adjacent to said pole piece faces with a gap therebelow to accommodate windings on the tracking circuit pole pieces.
Claim 10
Dependent Claim
19 words
A transducer head as claimed in claim 4, in which said stainless steel is constituted by laminations stacked together.
Claim 11
Dependent Claim
33 words
A transducer head as claimed in claim 1, in which each tracking circuit comprises a stack of laminations together forming a pole piece, with a proportion of said laminations being of stainless steel.
Claim 12
Dependent Claim
34 words
A transducer head as claimed in claim 1, in which the stainless steel has the composition: Carbon 0.12% Manganese 2% Silicon 1% Nickel 8 to 11% Chromium 17 to 20% and the remainder iron.
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) | 1978-02-03 | 1978-08-05 | 1979-02-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-02-03 | 1982-08-05 | 1983-02-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-02-03 | 1986-08-05 | 1987-02-04 | $7700.00 | Window Closed / Lapsed |