Patent US2134043A successfully refreshed from Google Patents.
Patent US3289428A successfully refreshed from Google Patents.
US3520138A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Convertible enginf
Assignee: RTX Corp
•
Filing: 1969-02-27
•
Granted: 1970-07-14
•
Expires: 1989-02-27
Abstract
No abstract record available.
Inventors
- 👤 Samuel S Fox
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 10:47
CPC Classifications
F; F02; F02C; F02C9/00; F02C9/16; F02C6/00; F02C6/20; F02C6/206; F02C7/00; F02C7/36; F02K; F02K3/00; F02K3/02; F02K3/04; F02K3/062; F02K3/075
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
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) | 1973-07-13 | 1974-01-12 | 1974-07-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-07-13 | 1978-01-12 | 1978-07-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-07-13 | 1982-01-12 | 1982-07-14 | $7700.00 | Window Closed / Lapsed |