Patent US3563568A successfully refreshed from Google Patents.
US3563568A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Variable ratio rotary drive mechanism and wheel chair embodying same
Assignee: Individual
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Filing: 1968-09-20
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Granted: 1971-02-16
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Expires: 1988-09-20
Abstract
Abstract A variable ratio rotary drive mechanism is provided for wheel chairs and other uses. The drive mechanism has a pair of concentric driving and driven members defining an intervening annular space containing a variable ratio gear train which drivably couples the members, whereby rotation of the driving member drives the driven member in rotation. A shift lever is provided for operating the gear train to vary its ratio and thereby the mechanical advantage of the drive mechanism. A wheel chair is provided having wheel assemblies embodying the rotary drive mechanism to permit adjustment of the force which the occupant of the chair must exert on the wheels to propel the chair.
Inventors
- 👤 Reuben V Sasse
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 12:24
CPC Classifications
A; A61; A61G; A61G5/00; A61G5/02
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
253 words
A wheel assembly for a wheel chair comprising: an axle, hub rotatable on said axle; a ground wheel surrounding and mounted on said hub; said axle having an end projecting beyond one end of said hub for rigid attachment to the frame of said wheel chair; a tubular driving shaft rotatable on said axle and having one end projecting beyond the opposite end of said hub; a hand wheel fixed to said one end of said driving shaft; a variable ratio gear transmission; and said transmission comprising first and second axially spaced internal ring gears in said hub, a sun gear rigid on said driving shaft, a carriage rotatable on and movable along said axle including a toothed drive plate. Planetary pinion means rotatable on said carriage, said carriage being movable along said axle between a direct drive position wherein the teeth on said drive plate mesh with said second ring gear and a slow speed position wherein said drive plate is disengaged from said second ring gear and said pinion means mesh with said sun gear and first ring gear, first clutch means on said carriage and driving shaft against relative rotation in said direct drive position, and second clutch means on said carriage and axle for locking said carriage and axle against relative rotation in said slow speed position, and shift means connected to said carriage including a handle accessible at the side of said wheel assembly adjacent said projecting end of said axle for shifting said carriage between said positions.
Claim 2
Dependent Claim
253 words
A wheel assembly for a wheel chair comprising: an axle, hub rotatable on said axle; a ground wheel surrounding and mounted on said hub; said axle having an end projecting beyond one end of said hub for rigid attachment to the frame of said wheel chair; a tubular driving shaft rotatable on said axle and having one end projecting beyond the opposite end of said hub; a hand wheel fixed to said one end of said driving shaft; a variable ratio gear transmission; and said transmission comprising first and second axially spaced internal ring gears in said hub, a sun gear rigid on said driving shaft, a carriage rotatable on and movable along said axle including a toothed drive plate. Planetary pinion means rotatable on said carriage, said carriage being movable along said axle between a direct drive position wherein the teeth on said drive plate mesh with said second ring gear and a slow speed position wherein said drive plate is disengaged from said second ring gear and said pinion means mesh with said sun gear and first ring gear, first clutch means on said carriage and driving shaft against relative rotation in said direct drive position, and second clutch means on said carriage and axle for locking said carriage and axle against relative rotation in said slow speed position, and shift means connected to said carriage including a handle accessible at the side of said wheel assembly adjacent said projecting end of said axle for shifting said carriage between said positions.
Claim 3
Dependent Claim
303 words
A wheel chair comprising: a chair frame; a pair of wheel assemblies at opposite sides, respectively, of said frame each including an axle having an inner end rigidly secured to said frame, a hub rotatable on said axle, a ground wheel surrounding and mounted on said hub, a tubular drive shaft rotatable on said axle and having an outer end projecting beyond the outer end of said hub, a hand wheel fixed to the outer end of said drive shaft, a variable ratio transmission within said hub drivably coupling said drive shaft and hub, and shift means accessible at the inner side of the respective wheel, assembly for adjusting the ratio of said transmission; each transmission comprising first and second axially spaced internal ring gears in said hub, a sun gear rigid on said driving shaft, a carriage rotatable on and movable along said axle including a toothed drive plate, pLanetary pinion means rotatable on said carriage, said carriage being movable along said axle between a direct drive position wherein the teeth on said drive plate mesh with said second ring gear and a slow speed position wherein said drive plate is disengaged from said second ring gear and said pinion means mesh with said sun gear and first ring gear, first clutch means on said carriage and driving shaft against relative rotation in said direct drive position, and second clutch means on said carriage and axle for locking said carriage and axle against relative rotation in said slow speed position; said shift means for each transmission comprising a handle connected to the respective carriage for shifting the latter between its direct drive and slow speed positions; and the transmissions of said wheel assemblies being adjustable to provide said transmissions with equal first ratios and equal second ratios differing from said first ratios.
Claim 4
Dependent Claim
303 words
A wheel chair comprising: a chair frame; a pair of wheel assemblies at opposite sides, respectively, of said frame each including an axle having an inner end rigidly secured to said frame, a hub rotatable on said axle, a ground wheel surrounding and mounted on said hub, a tubular drive shaft rotatable on said axle and having an outer end projecting beyond the outer end of said hub, a hand wheel fixed to the outer end of said drive shaft, a variable ratio transmission within said hub drivably coupling said drive shaft and hub, and shift means accessible at the inner side of the respective wheel, assembly for adjusting the ratio of said transmission; each transmission comprising first and second axially spaced internal ring gears in said hub, a sun gear rigid on said driving shaft, a carriage rotatable on and movable along said axle including a toothed drive plate, pLanetary pinion means rotatable on said carriage, said carriage being movable along said axle between a direct drive position wherein the teeth on said drive plate mesh with said second ring gear and a slow speed position wherein said drive plate is disengaged from said second ring gear and said pinion means mesh with said sun gear and first ring gear, first clutch means on said carriage and driving shaft against relative rotation in said direct drive position, and second clutch means on said carriage and axle for locking said carriage and axle against relative rotation in said slow speed position; said shift means for each transmission comprising a handle connected to the respective carriage for shifting the latter between its direct drive and slow speed positions; and the transmissions of said wheel assemblies being adjustable to provide said transmissions with equal first ratios and equal second ratios differing from said first ratios.
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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) | 1974-02-15 | 1974-08-17 | 1975-02-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-02-15 | 1978-08-17 | 1979-02-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-02-15 | 1982-08-17 | 1983-02-16 | $7700.00 | Window Closed / Lapsed |