US3506031A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Relief-makeup check assembly for directional control valves
Assignee: Parker Hannifin Corp
•
Filing: 1967-10-06
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Granted: 1970-04-14
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Expires: 1987-10-06
Abstract
No abstract record available.
Inventors
- 👤 Hugh J Stacey
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 00:47
CPC Classifications
F; F15; F15B; F15B13/00; F15B13/02; Y; Y10; Y10T; Y10T137/00; Y10T137/7722; Y10T137/7758; Y10T137/7762; Y10T137/7764; Y10T137/7766; Y10T137/7771; Y10T137/8593; Y10T137/87169; Y10T137/87233; Y10T137/87241
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2980135A
Cited
US3000397A
Cited
US3023584A
Cited
US3160167A
Cited
US3216446A
Cited
US3212523A
Cited
US3390700A
Cited
US3362430A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-04-13 | 1973-10-13 | 1974-04-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-04-13 | 1977-10-13 | 1978-04-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-04-13 | 1981-10-13 | 1982-04-14 | $7700.00 | Window Closed / Lapsed |