Wheel chair
First Claim
1. Apparatus for moving an object over substantially varying terrain, including stairs having stair treads, which comprises:
- a frame for supporting said object, said frame having opposite sides and a front portion and a rear portion;
first wheel means mounted from said front portion of said frame having a front wheel proximate each side of said frame for engagement with said terrain;
second wheel means mounted from said rear portion of said frame having a rear wheel proximate each side of said frame for engagement with said terrain;
drive means connected to at least one of said first and said second wheel means for rotating corresponding of said wheels against said terrain;
first level sensing means carried by said frame for continuously sensing any change in pitch of said frame from a pre-set pitch value;
means responsive to said first level sensing means connected between said frame and at least one of said first and second wheel means for correcting said pitch to said pre-set pitch value;
rotatable means carried by said frame for engaging said stair treads and for moving said frame ascending and descending said stairs, said rotatable means comprising a plurality of flexible endless members supported from said frame in a plane substantially perpendicular to said terrain, means for rotating said endless members, and stair tread engaging lugs attached to and extending outwardly from said endless members in said plane; and
means for selectively varying the relative rotational speed of said flexible endless members to facilitate the positioning of said tread engaging lugs of said endless members in supportive contact with said stair treads.
1 Assignment
0 Petitions
Accused Products
Abstract
A mechanism for the transport of an object across relatively level surfaces as well as to ascend and descend stairways. The mechanism is described particularly with respect to a wheel chair for handicapped persons and is provided with a frame and a pair of support wheels on each side of the frame. A climbing chain with lugs is associated with each wheel on the frame; these chains being inclined at an angle providing a desired lifting height. The wheel chair is either powered by the occupant or by electrical or other corresponding power means. Appropriate sensing means on the frame ascertain a nonlevel condition in pitch or yaw during ascent or descent of the stairs whereby corrections are made in the driving means such that a level orientation is re-established. Braking is provided by appropriate gearing whereby an interruption of the driving power holds the climbing chains in their current position. In one embodiment, the mechanism is provided with means for selectively varying the relative rotational speed of the various climbing chains to facilitate the substantially simultaneous loading of each climbing chain. Specific embodiments of drive trains and climbing chains are described.
234 Citations
17 Claims
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1. Apparatus for moving an object over substantially varying terrain, including stairs having stair treads, which comprises:
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a frame for supporting said object, said frame having opposite sides and a front portion and a rear portion; first wheel means mounted from said front portion of said frame having a front wheel proximate each side of said frame for engagement with said terrain; second wheel means mounted from said rear portion of said frame having a rear wheel proximate each side of said frame for engagement with said terrain; drive means connected to at least one of said first and said second wheel means for rotating corresponding of said wheels against said terrain; first level sensing means carried by said frame for continuously sensing any change in pitch of said frame from a pre-set pitch value; means responsive to said first level sensing means connected between said frame and at least one of said first and second wheel means for correcting said pitch to said pre-set pitch value; rotatable means carried by said frame for engaging said stair treads and for moving said frame ascending and descending said stairs, said rotatable means comprising a plurality of flexible endless members supported from said frame in a plane substantially perpendicular to said terrain, means for rotating said endless members, and stair tread engaging lugs attached to and extending outwardly from said endless members in said plane; and means for selectively varying the relative rotational speed of said flexible endless members to facilitate the positioning of said tread engaging lugs of said endless members in supportive contact with said stair treads. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
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9. Apparatus for moving an object over substantially varying terrain, including stairs having stair treads, which comprises:
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a frame for supporting said object, said frame having opposite sides and a front portion and a rear portion; first wheel means mounted from said front portion of said frame having a front wheel proximate each side of said frame for engagement with said terrain; second wheel means mounted from said rear portion of said frame having a rear wheel proximate each side of said frame for engagement with said terrain; drive means connected to at least one of said first and said second wheel means for rotating corresponding of said wheels against said terrain; first level sensing means carried by said frame for continuously sensing any change in pitch of said frame from a pre-set pitch value; means responsive to said first level sensing means connected between said frame and at least one of said first and second wheel means for correcting said pitch to said pre-set pitch value; a stair engaging means associated with each of said front wheels and said rear wheels for causing said apparatus to ascend or descend said stairs, said stair engaging means including an oval-shaped carrier unit having a peripheral flexible endless member mounted in a substantially vertical plane, means connected to said endless member for rotating said endless member about said carrier, and lugs extending from said endless member in said vertical plane for engagement with treads of said stairs; and means for selectively varying the relative rotational speed of said flexible endless members to facilitate the positioning of said lugs of said endless members in supportive contact with said stair treads. - View Dependent Claims (10, 11, 12, 13, 14, 15, 16, 17)
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Specification