US3302535A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydraulic piston and cylinder combinations
Assignee: English Drilling Equipment Co Ltd
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Filing: 1964-12-17
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Granted: 1967-02-07
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Expires: 1984-12-17
Abstract
No abstract record available.
Inventors
- 👤 Procter Reginald Henry
- 👤 Sanders Frederick Henr William
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 05:39
CPC Classifications
F; F15; F15B; F15B15/00; F15B15/08; F15B15/14; F15B15/16
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
165 words
A MULTI-STAGE HYDRAULIC PISTON AND CYLINDER DEVICE COMPRISING AN OUTER CYLINDER, AN INTERMEDIATE CYLINDER TELESCOPICALLY MOUNTED IN SAID OUTER CYLINDER FOR SLIDING THEREIN, BETWEEN RETRACTED AND EXTENDED POSITIONS, UNDER THE INFLUENCE OF LIQUID INTRODUCED INTO THE OUTER CYLINDER, SAID INTERMEDIATE CYLINDER INCLUDING A CYLINDRICAL WALL AND AN OUTWARDLY DIRECTED SHOULDER PORTION LEADING FROM SAID WALL, SAID SHOULDER PORTION CO-OPERATING PISTON-WISE WITH SAID OUTER CYLINDER WHEREBY WHEN SAID INTERMEDIATE CYLINDER IS IN A RETRACTED POSITION WITHIN SAID OUTER CYLINDER THE WALLS OF SAID CYLINDERS DEFINE AN ANNULAR SPACE THEREBETWEEN, INNER PISTON MEANS TELESCOPICALLY MOUNTED WITHIN SAID INTERMEDIATE CYLINDER FOR SLIDING THEREIN, BETWEEN RETRACTED AND EXTENDED POSITIONS, UNDER THE INFLUENCE OF LIQUID INTRODUCED INTO THE INTERMEDIATE CYLINDER, MEANS DEFINING PORT MEANS THROUGH SAID WALL OF SAID INTERMEDIATE CYLINDER AND MEANS THROUGH SAID WALL OF SAID INTERMEDIATE SAID ANNULAR SPACE THROUGH SAID PORT MEANS TO THE INTERIOR OF SAID INTERMEDIATE CYLINDER BEHIND SAID PISTON MEANS AS SAID INTERMEDIATE CYLINDER MOVES FROM ITS RETRACTED POSITION TOWARDS ITS EXTENDED PISTON.
Claim 2
Dependent Claim
165 words
A MULTI-STAGE HYDRAULIC PISTON AND CYLINDER DEVICE COMPRISING AN OUTER CYLINDER, AN INTERMEDIATE CYLINDER TELESCOPICALLY MOUNTED IN SAID OUTER CYLINDER FOR SLIDING THEREIN, BETWEEN RETRACTED AND EXTENDED POSITIONS, UNDER THE INFLUENCE OF LIQUID INTRODUCED INTO THE OUTER CYLINDER, SAID INTERMEDIATE CYLINDER INCLUDING A CYLINDRICAL WALL AND AN OUTWARDLY DIRECTED SHOULDER PORTION LEADING FROM SAID WALL, SAID SHOULDER PORTION CO-OPERATING PISTON-WISE WITH SAID OUTER CYLINDER WHEREBY WHEN SAID INTERMEDIATE CYLINDER IS IN A RETRACTED POSITION WITHIN SAID OUTER CYLINDER THE WALLS OF SAID CYLINDERS DEFINE AN ANNULAR SPACE THEREBETWEEN, INNER PISTON MEANS TELESCOPICALLY MOUNTED WITHIN SAID INTERMEDIATE CYLINDER FOR SLIDING THEREIN, BETWEEN RETRACTED AND EXTENDED POSITIONS, UNDER THE INFLUENCE OF LIQUID INTRODUCED INTO THE INTERMEDIATE CYLINDER, MEANS DEFINING PORT MEANS THROUGH SAID WALL OF SAID INTERMEDIATE CYLINDER AND MEANS THROUGH SAID WALL OF SAID INTERMEDIATE SAID ANNULAR SPACE THROUGH SAID PORT MEANS TO THE INTERIOR OF SAID INTERMEDIATE CYLINDER BEHIND SAID PISTON MEANS AS SAID INTERMEDIATE CYLINDER MOVES FROM ITS RETRACTED POSITION TOWARDS ITS EXTENDED PISTON.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1970-02-06 | 1970-08-08 | 1971-02-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-02-06 | 1974-08-08 | 1975-02-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-02-06 | 1978-08-08 | 1979-02-07 | $7700.00 | Window Closed / Lapsed |