US2828017A
Expired / Lapsed
US
⏱️ 0.0 years remaining
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Assignee: Individual
•
Filing: 1954-03-16
•
Granted: 1958-03-25
•
Expires: 1974-03-16
Abstract
No abstract record available.
Inventors
- 👤 Helmer A Ronningen
- 👤 William J Petter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 04:21
CPC Classifications
D; D21; D21G; D21G9/00; D21G9/0009; B; B01; B01D; B01D29/00; B01D29/11; B01D29/13; B01D29/15; B01D29/62; B01D29/66; B01D35/00; B01D35/12; B01D35/14; D21D; D21D5/00; D21D5/02; Y; Y10; Y10T; Y10T137/00; Y10T137/8593; Y10T137/86389; Y10T137/86405
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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GB404309A
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US2035758A
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US2184618A
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US2366903A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-03-24 | 1961-09-23 | 1962-03-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-03-24 | 1965-09-23 | 1966-03-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-03-24 | 1969-09-23 | 1970-03-25 | $7700.00 | Window Closed / Lapsed |