US3768495A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Crutch with adjustable handgrip
Assignee: Guardian Products Inc
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Filing: 1971-06-11
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Granted: 1973-10-30
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Expires: 1991-06-11
Abstract
Abstract The metal tubular shaft of a single-shaft crutch is locally reinforced by a slidable sleeve of substantial length that embraces the shaft and the sleeve carries a laterally extending handgrip. The sleeve is adjustable along the shaft to vary the distance of the handgrip from the upper end of the shaft. The length of the sleeve is not less than the distance from the axis of the shaft to the center of the applied load on the handgrip and therefore the lateral force transmitted to the shaft at each of the two ends of the sleeve is not more than the applied load.
Inventors
- 👤 A Smith
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 23:35
CPC Classifications
A; A61; A61H; A61H3/00; A61H3/02
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
247 words
A crutch including a tubular shaft comprising a first end, a second end, a substantially straight portion extending along a first axis from said first end to said second end, and a bent portion, integral with and extending from said second end and angularly related to said first axis, having a distal end, tubular extension means telescopically mounted on said shaft at said first end and having means for contacting and supporting the crutch relative to a surface being traversed by a user of the crutch, means for releasably fixing the telescopic relationship between said shaft And said extension means, first support means mounted on said distal end of said bent portion and defining a second axis passing through said first support means and said contacting and supporting means, second support means mounted on said tubular shaft and so oriented relative thereto as to intersect both said first and second axes, and means for adjustably mounting said second support means on said shaft comprising tubular means telescopically mounted on said shaft and having an upper end, a lower end, and a substantially straight portion extending between said upper and lower ends, said tubular means being substantially longer than the moment arm about said first axis of a force applied to said second support means, means for fixing said second support means to said mounting means, and means for releasably fastening said mounting means to said shaft for adjustment of the position of the former along the latter.
Claim 2
Dependent Claim
247 words
A crutch including a tubular shaft comprising a first end, a second end, a substantially straight portion extending along a first axis from said first end to said second end, and a bent portion, integral with and extending from said second end and angularly related to said first axis, having a distal end, tubular extension means telescopically mounted on said shaft at said first end and having means for contacting and supporting the crutch relative to a surface being traversed by a user of the crutch, means for releasably fixing the telescopic relationship between said shaft And said extension means, first support means mounted on said distal end of said bent portion and defining a second axis passing through said first support means and said contacting and supporting means, second support means mounted on said tubular shaft and so oriented relative thereto as to intersect both said first and second axes, and means for adjustably mounting said second support means on said shaft comprising tubular means telescopically mounted on said shaft and having an upper end, a lower end, and a substantially straight portion extending between said upper and lower ends, said tubular means being substantially longer than the moment arm about said first axis of a force applied to said second support means, means for fixing said second support means to said mounting means, and means for releasably fastening said mounting means to said shaft for adjustment of the position of the former along the latter.
Claim 3
Dependent Claim
28 words
The crutch of claim 1 including means fixed at said upper and lower ends of said tubular means for reducing play between said tubular means and said shaft.
Claim 4
Dependent Claim
24 words
The crutch of claim 1 wherein said first support means comprises armrest means which fits into an armpit of the user of the crutch.
Claim 5
Dependent Claim
29 words
The crutch of claim 1 wherein said first support means comprises cuff means which at least partially encircle a portion of the arm of a user of the crutch.
Claim 6
Dependent Claim
34 words
The crutch of claim 1 wherein said second axis is closer to the body of a user of the crutch, at the intersection thereof with said second support means, than is said first axis.
Claim 7
Dependent Claim
52 words
The crutch of claim 1 wherein the moment arm about said first axis of a force exerted upon said second support means, by a user of the crutch is substantially smaller than the moment arm along said first axis of the resultant force couple exerted by said tubular means on said shaft.
Claim 8
Dependent Claim
133 words
A crutch comprising a tubular shaft having a predetermined wall thickness, a handgrip for attachment to said shaft to support a user of the crutch, and means for attaching said handgrip to said shaft comprising sleeve means, concentrically mounted on said shaft, to which said handgrip is fixedly attached, said sleeve means having a length, relative to the moment arm of said handgrip about the axis of said shaft, sufficiently greater than said moment arm that damage to said shaft wall, by the force couple exerted on said shaft wall at the opposite ends of said sleeve as a result of a force imposed upon said handgrip, is prevented by a reduction of the size of the forces of the force couple relative to the size of the force exerted on said handgrip.
Claim 9
Dependent Claim
133 words
A crutch comprising a tubular shaft having a predetermined wall thickness, a handgrip for attachment to said shaft to support a user of the crutch, and means for attaching said handgrip to said shaft comprising sleeve means, concentrically mounted on said shaft, to which said handgrip is fixedly attached, said sleeve means having a length, relative to the moment arm of said handgrip about the axis of said shaft, sufficiently greater than said moment arm that damage to said shaft wall, by the force couple exerted on said shaft wall at the opposite ends of said sleeve as a result of a force imposed upon said handgrip, is prevented by a reduction of the size of the forces of the force couple relative to the size of the force exerted on said handgrip.
Claim 10
Dependent Claim
20 words
The crutch of claim 7 including means for adjusting the position of said sleeve along the axis of said shaft.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-10-29 | 1977-04-30 | 1977-10-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-29 | 1981-04-30 | 1981-10-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-29 | 1985-04-30 | 1985-10-30 | $7700.00 | Window Closed / Lapsed |