Patent US4740701A successfully refreshed from Google Patents.
Patent US3523239A successfully refreshed from Google Patents.
US3523239A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Voltage regulated step-up apparatus
Assignee: SYSTEMS ENG ELECTRONICS Inc
•
Filing: 1967-12-11
•
Granted: 1970-08-04
•
Expires: 1987-12-11
Abstract
No abstract record available.
Inventors
- 👤 William L Heard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 10:40
CPC Classifications
H; H02; H02M; H02M3/00; H02M3/02; H02M3/04; H02M3/10; H02M3/145; H02M3/155; H02M3/156
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US3263099A
Cited
US3381202A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-08-03 | 1974-02-02 | 1974-08-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-08-03 | 1978-02-02 | 1978-08-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-08-03 | 1982-02-02 | 1982-08-04 | $7700.00 | Window Closed / Lapsed |