Patent US3251491A successfully refreshed from Google Patents.
US3251491A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Earth-working implement
Assignee: Deere and Co
•
Filing: 1964-05-07
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Granted: 1966-05-17
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Expires: 1984-05-07
Abstract
No abstract record available.
Inventors
- 👤 John L French
- 👤 Thomas C Schrader
- 👤 Albert J Van Auwelaer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 08:55
CPC Classifications
E; E02; E02F; E02F3/00; E02F3/04; E02F3/28; E02F3/36; E02F3/42; E02F3/425; E02F3/30; E02F3/32; E02F3/38; E02F9/00; E02F9/08; E02F9/085
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
158 words
ON A BACKHOE INCLUDING A FRAME, A BOOM PIVOTED FOR VERTICAL MOVEMENT ON THE FRAME, A DIPPER STICK INCLUDING A MAIN PORTION PIVOTED ON THE END OF THE BOOM FOR VERTICAL MOVEMENT AND AN EXTENSION SUPPORTED ON THE PORTION FOR LONGITUDINAL MOVEMENT RELATIVE THERETO BETWEEN EXTENDED AND RETRACTED POSITION, POWER MEANS FOR EFFECTING VERTICAL MOVEMENT OF THE BOOM AND DIPPER STICK ABOUT THE PIVOTS, DETACHABLE LOCKING MEANS FOR RETAINING THE EXTENSION IN THE EXTENDED AND RETRACTED POSITIONS, AND A MATERIAL HANDLING DEVICE ON THE END OF THE EXTENSION, THE IMPROVEMENT RESIDING IN A METHOD OF RETRACTING THE EXTENSION FROM ITS EXTENDED POSITION COMPRISING: POSITIONING THE BOOM AND DIPPER STICK WHEREBY THE DIPPER STICK IS VERTICALLY DISPOSED AND THE MATERIAL HANDLING DEVICE ENGAGES A COMPARATIVELY IMMOVABLE SURFACE; REMOVING THE DETACHABLE LOCKING MEANS BETWEEN THE MAIN PORTION AND EXTENSION ON THE DIPPER STICK; LOWERING THE BOOM TO FORCE RETRACTION OF THE EXTENSION; AND LOCKING THE EXTENSION IN ITS RETRACTED POSITION.
Claim 2
Dependent Claim
158 words
ON A BACKHOE INCLUDING A FRAME, A BOOM PIVOTED FOR VERTICAL MOVEMENT ON THE FRAME, A DIPPER STICK INCLUDING A MAIN PORTION PIVOTED ON THE END OF THE BOOM FOR VERTICAL MOVEMENT AND AN EXTENSION SUPPORTED ON THE PORTION FOR LONGITUDINAL MOVEMENT RELATIVE THERETO BETWEEN EXTENDED AND RETRACTED POSITION, POWER MEANS FOR EFFECTING VERTICAL MOVEMENT OF THE BOOM AND DIPPER STICK ABOUT THE PIVOTS, DETACHABLE LOCKING MEANS FOR RETAINING THE EXTENSION IN THE EXTENDED AND RETRACTED POSITIONS, AND A MATERIAL HANDLING DEVICE ON THE END OF THE EXTENSION, THE IMPROVEMENT RESIDING IN A METHOD OF RETRACTING THE EXTENSION FROM ITS EXTENDED POSITION COMPRISING: POSITIONING THE BOOM AND DIPPER STICK WHEREBY THE DIPPER STICK IS VERTICALLY DISPOSED AND THE MATERIAL HANDLING DEVICE ENGAGES A COMPARATIVELY IMMOVABLE SURFACE; REMOVING THE DETACHABLE LOCKING MEANS BETWEEN THE MAIN PORTION AND EXTENSION ON THE DIPPER STICK; LOWERING THE BOOM TO FORCE RETRACTION OF THE EXTENSION; AND LOCKING THE EXTENSION IN ITS RETRACTED POSITION.
References Cited (Backward Citations)
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Cited
US1650255A
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US2575564A
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US2802584A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1969-05-16 | 1969-11-15 | 1970-05-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-05-16 | 1973-11-15 | 1974-05-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-05-16 | 1977-11-15 | 1978-05-17 | $7700.00 | Window Closed / Lapsed |