US3373416A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Multiple magnetic head assembly
Assignee: US Philips Corp
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Filing: 1965-02-18
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Granted: 1968-03-12
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Expires: 1985-02-18
Abstract
No abstract record available.
Inventors
- 👤 Geurst Jan Albert
- 👤 Walther George Ludwig
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 04:34
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/10; G11B5/11; G11B5/265; G11B5/29
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
141 words
A DEVICE FOR REDUCING OR SUPPRESSING THE RELATIVE INFLUENCE IN A MULTIPLE MAGNETIC HEAD FOR RECORDING AND REPRODUCING ONE OR MORE PARALLEL RECORDS IN ONE OR MORE PARALLEL CORRESPONDING TRACKS ON A UNILATERALLY MAGNETISABLE CARRIER, SAID HEADS COMPRISING AT LEAST TWO MAGNETIC CIRCUITS ONE FOR RECORDING AND ONE FOR REPRODUCING LYING ONE AFTER THE OTHER AND CONNECTED WITH EACH OTHER, EACH CIRCUIT CONSISTING OF AT LEAST TWO PORTIONS OF SINTERED, OXIDIC, FERROMAGNETIC MATERIAL, AND HAVING A USEFUL GAP FILLED WITH NON-MAGNETISABLE MATERIAL BETWEEN SAID TWO PORTIONS AND AFFIXING THE TWO PORTIONS TO EACH OTHER, AT LEAST TWO PLATES OF SINTERED, OXIDIC, FERROMAGNETIC MATERIAL ARRANGED BETWEEN SAID MAGNETIC CIRCUITS, AT LEAST ONE PLATE OF ELECTRICALLY CONDUCTING, NON-MAGNETISABLE MATERIAL ARRANGED BETWEEN SAID TWO PLATES, A PLATE OF ELECTRICALLY CONDUCTING, NON-MAGNETISABLE MATERIAL POSITIONED BETWEEN ON CIRCUIT AND THE ADJACENT PLATE OF SINTERED, OXIDIC FERRO-
Claim 2
Independent Claim
141 words
A DEVICE FOR REDUCING OR SUPPRESSING THE RELATIVE INFLUENCE IN A MULTIPLE MAGNETIC HEAD FOR RECORDING AND REPRODUCING ONE OR MORE PARALLEL RECORDS IN ONE OR MORE PARALLEL CORRESPONDING TRACKS ON A UNILATERALLY MAGNETISABLE CARRIER, SAID HEADS COMPRISING AT LEAST TWO MAGNETIC CIRCUITS ONE FOR RECORDING AND ONE FOR REPRODUCING LYING ONE AFTER THE OTHER AND CONNECTED WITH EACH OTHER, EACH CIRCUIT CONSISTING OF AT LEAST TWO PORTIONS OF SINTERED, OXIDIC, FERROMAGNETIC MATERIAL, AND HAVING A USEFUL GAP FILLED WITH NON-MAGNETISABLE MATERIAL BETWEEN SAID TWO PORTIONS AND AFFIXING THE TWO PORTIONS TO EACH OTHER, AT LEAST TWO PLATES OF SINTERED, OXIDIC, FERROMAGNETIC MATERIAL ARRANGED BETWEEN SAID MAGNETIC CIRCUITS, AT LEAST ONE PLATE OF ELECTRICALLY CONDUCTING, NON-MAGNETISABLE MATERIAL ARRANGED BETWEEN SAID TWO PLATES, A PLATE OF ELECTRICALLY CONDUCTING, NON-MAGNETISABLE MATERIAL POSITIONED BETWEEN ON CIRCUIT AND THE ADJACENT PLATE OF SINTERED, OXIDIC FERRO-
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) | 1971-03-12 | 1971-09-11 | 1972-03-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-03-12 | 1975-09-11 | 1976-03-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-03-12 | 1979-09-11 | 1980-03-12 | $7700.00 | Window Closed / Lapsed |