US1996136A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for producing soft boiler water
Assignee: DURO CO
•
Filing: 1931-04-30
•
Granted: 1935-04-02
•
Expires: 1951-04-30
Abstract
No abstract record available.
Inventors
- 👤 Arthur C Zimmerman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:26
CPC Classifications
B; B01; B01D; B01D35/00; B01D35/18
Claims Analysis
Total Claims: 0
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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) | 1938-04-01 | 1938-10-01 | 1939-04-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1942-04-01 | 1942-10-01 | 1943-04-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1946-04-01 | 1946-10-01 | 1947-04-02 | $7700.00 | Window Closed / Lapsed |