US3248879A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Constant pressure source for valves
Assignee: ACF Industries Inc
•
Filing: 1965-04-22
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Granted: 1966-05-03
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Expires: 1985-04-22
Abstract
No abstract record available.
Inventors
- 👤 Paul J Natho
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 10:09
CPC Classifications
F; F16; F16K; F16K31/00; F16K31/12; E; E21; E21B; E21B34/00; E21B34/02; E21B34/04
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
96 words
THE METHOD OF CONTROLLING LONGITUDINAL MOVEMENT OF AN OPERATING STEM HAVING A PISTON FIXED AT ONE END THEROF AND WHICH PISTON IS CONFINED WITHIN A CYLINDER AND DIVIDES THE CYLINDER INTO FIRST AND SECOND COMPARTMENTS, SAID METHOD COMPRISING THE STEPS OF ACTUATING THE OPERATING STEM IN ONE DIRECTION BY A SOURCE OF FLUID PRESSURE COMMUNICATED INTO SAID FIRST COMPARTMENT, RETURNING THE OPERATING STEM TO ITS INITIAL POSITION UPON REDUCTION OF THE PRESSURE FROM THE SOURCE OF FLUID PRESSURE BY PROVIDING A SECOND SOURCE OF FLUID PRESSURE IN THE SECOND COMPARTMENT NORMALLY AVAILABLE TO THE PISTON WHICH
Claim 2
Independent Claim
96 words
THE METHOD OF CONTROLLING LONGITUDINAL MOVEMENT OF AN OPERATING STEM HAVING A PISTON FIXED AT ONE END THEROF AND WHICH PISTON IS CONFINED WITHIN A CYLINDER AND DIVIDES THE CYLINDER INTO FIRST AND SECOND COMPARTMENTS, SAID METHOD COMPRISING THE STEPS OF ACTUATING THE OPERATING STEM IN ONE DIRECTION BY A SOURCE OF FLUID PRESSURE COMMUNICATED INTO SAID FIRST COMPARTMENT, RETURNING THE OPERATING STEM TO ITS INITIAL POSITION UPON REDUCTION OF THE PRESSURE FROM THE SOURCE OF FLUID PRESSURE BY PROVIDING A SECOND SOURCE OF FLUID PRESSURE IN THE SECOND COMPARTMENT NORMALLY AVAILABLE TO THE PISTON WHICH
References Cited (Backward Citations)
US2193125A
Cited
GB647347A
Cited
US2805854A
Cited
US2674194A
Cited
US2918085A
Cited
US2926934A
Cited
FR1165733A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1969-05-02 | 1969-11-01 | 1970-05-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-05-02 | 1973-11-01 | 1974-05-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-05-02 | 1977-11-01 | 1978-05-03 | $7700.00 | Window Closed / Lapsed |