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US4726516A
Expired / Lapsed
US
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Foldable ramp
Assignee: Individual
•
Filing: 1987-04-06
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Granted: 1988-02-23
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Expires: 2007-04-06
Abstract
Abstract A pair of coplanar, telescopic tracks are held in a spaced-apart and generally parallel relationship by a plurality of crossties. The crossties may also be telescopic to vary the space between the tracks according to use. At one end the tracks can be elevated by length-adjustable props or variable trusses. Each track comprises at least two segments, a first segment adapted to be slidably disposed in a channel of the second segment. The segments can be channel bars. A detent is used to temporarily hold the tracks at any of a plurality of telescoped lengths. A variable truss comprises a pair of divergent struts with a variable length member subtending the angle between the struts. This device is especially useful as a variable ramp for wheelchairs when it is made from relatively lightweight material such as aluminum.
Inventors
- 👤 Ian C. Cree
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 21:47
CPC Classifications
E; E01; E01B; E01B23/00
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
117 words
A ramp frame comprising: a frame including a pair of coplanar, telescopic tracks held in a spaced-apart and generally parallel relationship by a plurality of crossties; a pair of length-adjustable prop means disposed below an elevatable end of the ramp frame for elevating said end above the opposite end of the ramp frame; means for temporarily holding the tracks at any of a plurality of telescoped lengths; and a telescopic under frame pivotally affixed at one end to the prop means, and pivotally affixed at one opposite end to the ramp frame at a ramp frame end remote from the prop means, and means for temporarily holding the underframe at any of a plurality of telescoped lengths.
Claim 2
Dependent Claim
117 words
A ramp frame comprising: a frame including a pair of coplanar, telescopic tracks held in a spaced-apart and generally parallel relationship by a plurality of crossties; a pair of length-adjustable prop means disposed below an elevatable end of the ramp frame for elevating said end above the opposite end of the ramp frame; means for temporarily holding the tracks at any of a plurality of telescoped lengths; and a telescopic under frame pivotally affixed at one end to the prop means, and pivotally affixed at one opposite end to the ramp frame at a ramp frame end remote from the prop means, and means for temporarily holding the underframe at any of a plurality of telescoped lengths.
Claim 3
Dependent Claim
128 words
A ramp comprising: a frame including a pair of coplanar telescopic tracks held in a variably spaced-apart relationship by a plurality of telescopic crosstie members; a pair of length-adjustable prop means disposed below an elevatable end of the ramp frame for elevating said end above the opposite end of the frame; means for temporarily holding the tracks at any of a plurality of telescoped lengths; means for temporarily holding the crossties at any of a plurality of telescoped lengths; and a telescopic underframe pivotally affixed at one end to the prop means, and pivotally affixed at an opposite end to the ramp frame at a ramp frame end remote from the prop means, and means for temporarily holding the underframe at any of a plurality of telescoped lengths.
Claim 4
Dependent Claim
128 words
A ramp comprising: a frame including a pair of coplanar telescopic tracks held in a variably spaced-apart relationship by a plurality of telescopic crosstie members; a pair of length-adjustable prop means disposed below an elevatable end of the ramp frame for elevating said end above the opposite end of the frame; means for temporarily holding the tracks at any of a plurality of telescoped lengths; means for temporarily holding the crossties at any of a plurality of telescoped lengths; and a telescopic underframe pivotally affixed at one end to the prop means, and pivotally affixed at an opposite end to the ramp frame at a ramp frame end remote from the prop means, and means for temporarily holding the underframe at any of a plurality of telescoped lengths.
References Cited (Backward Citations)
US484086A
Cited
US963918A
Cited
US1348142A
Cited
US1558581A
Cited
US2076069A
Cited
US3074241A
Cited
US3936898A
Cited
US4013268A
Cited
US4107932A
Cited
US4528711A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-02-22 | 1991-08-24 | 1992-02-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-02-22 | 1995-08-24 | 1996-02-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-02-22 | 1999-08-24 | 2000-02-23 | $7700.00 | Window Closed / Lapsed |