US4222449A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Step-climbing wheel chair
Assignee: Individual
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Filing: 1978-06-08
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Granted: 1980-09-16
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Expires: 1998-06-08
Abstract
Abstract An improved step-climbing wheel chair with integral retractable ramps for ascending or descending a step, curb or the like. The conveyance is provided with a two-speed transmission capable of driving the wheel chair on level terrain at conventional speeds or selecting a low speed high torque capability for driving the conveyance up an inclined ramp. The invention further contains a self-leveling chair seat which automatically maintains the occupant in a level seated position regardless of the inclined position assumed by the wheel chair frame, thereby contributing to the stability of the wheel chair and the safety of the occupant.
Inventors
- 👤 Jack M. Feliz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 21:17
CPC Classifications
A; A61; A61G; A61G5/00; A61G5/06; B; B60; B60L; B60L15/00; B60L15/20; B60L15/2009; B60L15/2054; B60L7/00; B60L7/003; A61G5/04; A61G5/041; A61G5/045; A61G5/10; A61G5/1056; A61G5/1075; B60L2200/00; B60L2200/34; B60L2220/00; B60L2220/40; B60L2220/46; B60L2240/00; B60L2240/40; B60L2240/42; B60L2240/421; B60L2240/423; B60L2250/00; B60L2250/24; Y; Y02; Y02T; Y02T10/00; Y02T10/60; Y02T10/64; Y02T10/72; Y10; Y10S; Y10S280/00; Y10S280/10
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
166 words
In a wheel chair for ascending and descending a step, curb or the like, the combination of: a frame with castor wheels and drive wheels mounted thereon; a pair of elongate substantially flat ramps; a foldable, extendable and retractable ramp supporting assembly carrying said ramps and pivotally mounted on said frame; a self-leveling seat pivotally mounted on said frame; a first power drive means interconnecting said chair and frame and automatically energized to maintain the said seat in a level position regardless of an inclined position assumed by said frame; a control means carried on said ramp supporting assembly for extending, positioning, retracting and folding said ramps relative to said frame for traverse by said castor and drive wheels; and a second power drive means mounted on said frame and including a multi-speed transmission for driving said drive wheels on level terrain at conventional speeds and at a low speed with high torque up said ramps and functioning as a speed restraint while descending said ramp.
Claim 2
Dependent Claim
166 words
In a wheel chair for ascending and descending a step, curb or the like, the combination of: a frame with castor wheels and drive wheels mounted thereon; a pair of elongate substantially flat ramps; a foldable, extendable and retractable ramp supporting assembly carrying said ramps and pivotally mounted on said frame; a self-leveling seat pivotally mounted on said frame; a first power drive means interconnecting said chair and frame and automatically energized to maintain the said seat in a level position regardless of an inclined position assumed by said frame; a control means carried on said ramp supporting assembly for extending, positioning, retracting and folding said ramps relative to said frame for traverse by said castor and drive wheels; and a second power drive means mounted on said frame and including a multi-speed transmission for driving said drive wheels on level terrain at conventional speeds and at a low speed with high torque up said ramps and functioning as a speed restraint while descending said ramp.
Claim 3
Dependent Claim
28 words
A wheel chair as defined in claim 1 wherein said ramp supporting assembly includes manually actuable control handles slidably mounted therein for moving generally parallel to said ramp.
Claim 4
Dependent Claim
22 words
A wheel chair as defined in claim 2 including brake means for locking said control handles relative to said ramp supporting assembly.
Claim 5
Dependent Claim
24 words
A wheel chair as defined in claim 3 including second control means carried on said control handles for controlling said second power drive means.
Claim 6
Dependent Claim
45 words
A wheel chair as defined in claim 1 wherein said seat is pivotally mounted on said frame at a pivot point below the seat whereby the seat is pivoted forwardly when the wheel chair is ascending and pivoted rearwardly when the wheel chair is descending.
Claim 7
Dependent Claim
24 words
A wheel chair as defined in claim 1 including auxiliary ramps pivotally mounted at and extending from each end of each of said ramps.
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) | 1983-09-16 | 1984-03-17 | 1984-09-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-09-16 | 1988-03-17 | 1988-09-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-09-16 | 1992-03-17 | 1992-09-16 | $7700.00 | Window Closed / Lapsed |