Patent US3562725A successfully refreshed from Google Patents.
US3562725A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Coarse and fine positioning of magnetic read heads
Assignee: Unisys Corp
•
Filing: 1968-10-15
•
Granted: 1971-02-09
•
Expires: 1988-10-15
Abstract
Abstract THE PRESENT SYSTEM PROVIDES A CIRCUIT WHEREBY THE ELECTRICAL CURRENTS THROUGH THE STATOR WINDINGS OF A MAGNETIC DETENT MOTOR ARE (1) ALTERED IN PHASE RELATIONSHIP TO EFFECT A COARSE POSITIONING OF MAGNETIC READ/WRITE HEADS WHICH ARE MECHANICALLY COUPLED TO SAID MAGNETIC DETENT MOTOR AND (2) ALTERED IN AMPLITUDE IN RESPONSE TO A FEEDBACK SIGNAL IN ORDER THAT THE ROTOR OF THE DETENT MOTOR CAN BE RELOCATED BY SMALL INCREMENTS, I.E., SMALL DISTANCES.
Inventors
- 👤 Rudolph J Klein
- 👤 Edmund J Crossen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 05:23
CPC Classifications
H; H02; H02K; H02K37/00; H02K37/10; H02K37/12; H02K37/14; G; G05; G05D; G05D3/00; G05D3/12; G05D3/14; G11; G11B; G11B5/00; G11B5/48; G11B5/54; G11B5/55; G11B5/5521; G11B5/5552; G11B5/5556; G11B5/556
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-02-08 | 1974-08-10 | 1975-02-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-02-08 | 1978-08-10 | 1979-02-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-02-08 | 1982-08-10 | 1983-02-09 | $7700.00 | Window Closed / Lapsed |