US3587394A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High speed control valve for hydraulic drives
Assignee: Maschinenfabrik Köppern GmbH and Co KG
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Filing: 1968-07-19
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Granted: 1971-06-28
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Expires: 1988-07-19
Abstract
Abstract AN IMPROVED HYDRAULIC DRIVE WITH A RECIPROCATING WORKING PISTON WHOSE SIDE REMOTE FROM THE LOAD MAY BE AFFECTED BY A LIQUID OR GASEOUS PRESSURE MEDIUM, AND COMPRISING A CONTROL VALVE WITH AN AXIALLY DISPLACEABLE CONTROL SLIDE, ADAPTED TO MOVE IN A CONTROL SLEEVE WITH RADIALLY DISPOSED INLET AND OUTLET ORIFICES, WHEREIN THE IMPROVEMENT COMPRISES ADAPTATION FOR HIGH OPERATING FREQUENCIES IN THAT THE CONTROL SLEEVE IS AXIALLY DISPLACEABLE IN THE VALVE HOUSING AND IS DIRECTLY CONNECTED WITH THE PISTON, AND BY PROVIDING A REVOLVING CAM FOR PERIODICALLY MOVING THE SPRING-LOADED PISTON SLIDE.
Inventors
- 👤 Jan Willem Hilbrands
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 20:11
CPC Classifications
F; F15; F15B; F15B9/00; F15B9/02; F15B9/08; F15B9/10
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) | 1974-06-27 | 1974-12-27 | 1975-06-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-06-27 | 1978-12-27 | 1979-06-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-06-27 | 1982-12-27 | 1983-06-28 | $7700.00 | Window Closed / Lapsed |