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Patent US3472000A successfully refreshed from Google Patents.
US3472000A
Expired / Lapsed
US
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Air dryer and purge control unit
Assignee: Westinghouse Air Brake Co
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Filing: 1968-04-29
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Granted: 1969-10-14
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Expires: 1988-04-29
Abstract
No abstract record available.
Inventors
- 👤 Willlam H Glass
- 👤 Robert J Bridigum
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 22:14
CPC Classifications
F; F04; F04B; F04B39/00; F04B39/16; B; B01; B01D; B01D53/00; B01D53/26; F22; F22B; F22B37/00; F22B37/02; F22B37/26; F22B37/265
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2584889A
Cited
US2569537A
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US3080693A
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US3182435A
Cited
US3080977A
Cited
US3160486A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-10-13 | 1973-04-14 | 1973-10-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-10-13 | 1977-04-14 | 1977-10-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-10-13 | 1981-04-14 | 1981-10-14 | $7700.00 | Window Closed / Lapsed |