US3440511A
Expired / Lapsed
US
⏱️ 0.0 years remaining
D.c. motor control system
Assignee: AT&T Inc
•
Filing: 1967-02-14
•
Granted: 1969-04-22
•
Expires: 1987-02-14
Abstract
No abstract record available.
Inventors
- 👤 Yoshiaki Igarashi
- 👤 Kazutsugu Kobayashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 07:56
CPC Classifications
H; H02; H02P; H02P3/00; H02P3/06; H02P3/08; H02P3/12; H02P7/00; H02P7/06; H02P7/18; H02P7/24; H02P7/28; H02P7/285; H02P7/288; H02P7/2885
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US3188547A
Cited
US3371259A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-04-21 | 1972-10-21 | 1973-04-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-04-21 | 1976-10-21 | 1977-04-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-04-21 | 1980-10-21 | 1981-04-22 | $7700.00 | Window Closed / Lapsed |