Patent US3235172A successfully refreshed from Google Patents.
US3235172A
Expired / Lapsed
US
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Vacuum pump
Assignee: Welch Scientific Co
•
Filing: 1964-10-01
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Granted: 1966-02-15
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Expires: 1984-10-01
Abstract
No abstract record available.
Inventors
- 👤 Dubrovin John
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 07:25
CPC Classifications
F; F04; F04C; F04C27/00; F04C27/02; F04C18/00; F04C18/30; F04C18/34; F04C18/344
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US351231A
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US986116A
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FR512155A
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US1952834A
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US2359903A
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US2495771A
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US2514521A
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US2672282A
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US2831631A
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US2810348A
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US2924178A
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US2952249A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1969-02-14 | 1969-08-16 | 1970-02-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-02-14 | 1973-08-16 | 1974-02-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-02-14 | 1977-08-16 | 1978-02-15 | $7700.00 | Window Closed / Lapsed |