US1769808A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heat-exchange apparatus
Assignee: Individual
•
Filing: 1927-11-02
•
Granted: 1930-07-01
•
Expires: 1947-11-02
Abstract
No abstract record available.
Inventors
- 👤 Stancliffe Cecil Wheatley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 23:36
CPC Classifications
F; F28; F28F; F28F13/00; F28F13/06; F28F13/12; F28F13/02; F28F13/125; F28F19/00
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) | 1933-06-30 | 1933-12-30 | 1934-07-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1937-06-30 | 1937-12-30 | 1938-07-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1941-06-30 | 1941-12-30 | 1942-07-01 | $7700.00 | Window Closed / Lapsed |