Patent US3253837A successfully refreshed from Google Patents.
US3253837A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Stair climbing wheel chair
Assignee: Individual
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Filing: 1963-03-27
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Granted: 1966-05-31
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Expires: 1983-03-27
Abstract
No abstract record available.
Inventors
- 👤 Waverly V Johnson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 07:34
CPC Classifications
A; A61; A61G; A61G5/00; A61G5/06; A61G5/061
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
134 words
A STAIR CLIMBING WHEEL CHAIR COMPRISING A CHAIR FRAME, FRONT WHEELS CONNECTED TO THE CHAIR FRAME, LARGER REAR WHEELS STRADDLING THE CHAIR FRAME, EACH REAR WHEEL INCLUDING A LARGE ANNULAR HUB AND A RIM JOURNALED ON SAID HUB, SAID FRAME INCLUDING EXTENSIBLE REAR LEGS PIVOTALLY CONNECTED TO PARTS OF THE CHAIR FRAME, MEANS PIVOTALLY CONNECTING LOWER ENDS OF SAID LEGS TO THE WHEEL HUBS ECCENTRICALLY OF THE REAR WHEELS, MEANS FOR EXTENDING SAID REAR LEGS FOR POSITIONING THE FRAME IN SUBSTANTIALLY AN UPRIGHT POSITION, MEANS FOR RETRACTING SAID REAR LEGS FOR TILTING THE FRAME DOWNWARDLY AND REARWARDLY, AND LATCH MEANS RELEASABLY LATCHING EACH RIM TO THE HUB THEREOF TO PREVENT ROTATION OF THE RIM IN ONE DIRECTION RELATIVE TO THE HUB AND TO PREVENT TURNING OF THE HUB IN ONE DIRECTION WITHIN THE WHEEL.
Claim 2
Dependent Claim
134 words
A STAIR CLIMBING WHEEL CHAIR COMPRISING A CHAIR FRAME, FRONT WHEELS CONNECTED TO THE CHAIR FRAME, LARGER REAR WHEELS STRADDLING THE CHAIR FRAME, EACH REAR WHEEL INCLUDING A LARGE ANNULAR HUB AND A RIM JOURNALED ON SAID HUB, SAID FRAME INCLUDING EXTENSIBLE REAR LEGS PIVOTALLY CONNECTED TO PARTS OF THE CHAIR FRAME, MEANS PIVOTALLY CONNECTING LOWER ENDS OF SAID LEGS TO THE WHEEL HUBS ECCENTRICALLY OF THE REAR WHEELS, MEANS FOR EXTENDING SAID REAR LEGS FOR POSITIONING THE FRAME IN SUBSTANTIALLY AN UPRIGHT POSITION, MEANS FOR RETRACTING SAID REAR LEGS FOR TILTING THE FRAME DOWNWARDLY AND REARWARDLY, AND LATCH MEANS RELEASABLY LATCHING EACH RIM TO THE HUB THEREOF TO PREVENT ROTATION OF THE RIM IN ONE DIRECTION RELATIVE TO THE HUB AND TO PREVENT TURNING OF THE HUB IN ONE DIRECTION WITHIN THE WHEEL.
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) | 1969-05-30 | 1969-11-29 | 1970-05-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-05-30 | 1973-11-29 | 1974-05-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-05-30 | 1977-11-29 | 1978-05-31 | $7700.00 | Window Closed / Lapsed |