US2986899A
Expired / Lapsed
US
⏱️ 0.0 years remaining
System for maintaining pressure in refrigeration systems
Assignee: Alco Valve Co
•
Filing: 1957-12-23
•
Granted: 1961-06-06
•
Expires: 1977-12-23
Abstract
No abstract record available.
Inventors
- 👤 John A Schenk
- 👤 Ralph B Tilney
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 18:59
CPC Classifications
F; F25; F25B; F25B49/00; F25B49/02; F25B49/027; Y; Y10; Y10S; Y10S62/00; Y10S62/17; Y10T; Y10T137/00; Y10T137/2496; Y10T137/2559; Y10T137/2564
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US1303762A
Cited
US1239617A
Cited
US2252300A
Cited
US2564310A
Cited
US2761287A
Cited
US2869330A
Cited
US2874550A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-06-05 | 1964-12-05 | 1965-06-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-06-05 | 1968-12-05 | 1969-06-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-06-05 | 1972-12-05 | 1973-06-06 | $7700.00 | Window Closed / Lapsed |