Two-probe three-gap flux sensitive magnetic head
Abstract
Abstract 896,337. Magnetic flux-sensitive heads. INTERNATIONAL BUSINESS MACHINES CORPORATION. March 6, 1961 [March 18, 1960 (2)], No. 8003/61. Class 40 (2). Successive gaps, 46, 48, scanning the same digital track in a magnetic record are associated with complementary magnetic circuits 10, 12, all or parts of which are periodically saturated by modulators, 18 or 38. In Fig. 1, an output, at double the modulation frequency is produced in a winding 16 when an NRZ changeover is passing or stationary between the gaps. In Fig. 4, two half-track heads with staggered gaps and opposed series-connected windings react as in Fig. 5 to the passing of a changeover point to give a sharp output pulse of length equal to the gap-spacing. A stacked multi-track head of either type may share a single modulator threaded through all the head elements.
Inventors
- 👤 Chang David
Bibliographic Details
Claims Analysis
Total Claims: 0References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1971-08-27 | 1972-02-26 | 1972-08-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-08-27 | 1976-02-26 | 1976-08-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-08-27 | 1980-02-26 | 1980-08-27 | $7700.00 | Window Closed / Lapsed |