Wheelchair

• US 4,247,125 A
• Filed: 05/07/1979
• Issued: 01/27/1981
• Est. Priority Date: 05/08/1978
• Status: Expired due to Term

• Current Assignee: Ena M. Rayment
• Original Assignee: Ena M. Rayment
• Inventors: Rayment, Ena M.
• Primary Examiner(s): Love, John J.
• Assistant Examiner(s): Schrecengost, Randall A.
• Application Number:
  US06/036,444
• Time in Patent Office: 631 Days
• Field of Search: 280/5.2, 280/5.22, 280/5.24, 280/5.26, 280/5.28, 280/5.3, 280/5.32, 280/242 WC, 280/211, 280/249, 280/250, 280/DIG. 10, 280/767, 280/47.16, 280/47.2 , 280/289 WC, 280/79.2, 180/8 R, 180/8 A, 180/DIG. 3, 180/11, 180/15, 180/21, 180/22, 297/DIG. 4
• US Class Current: 280/5.24
• CPC Class Codes: A61G 5/06 with obstacle mounting facilities, e.g. for climbing stairs, kerbs or steps

Abstract

A wheelchair is constructed so as to be able to mount curbs, and overcome similar obstacles. In front and above each main wheel of the wheelchair, an auxiliary wheel or wheels are mounted, so that the auxiliary wheels will contact the obstacle at a point on their circumference below their center in such a way that they are able to ride up over the obstacle and lift the main wheels to a position where they can do likewise.

Claims

1. A wheelchair having a plurality of ground-engaging wheels rotatable about respective spaced front and rear axes, and at least one auxiliary ground wheel associated with each ground-engaging wheel axis, each auxiliary wheel being mounted for rotation about an axis which is parallel to the associated ground-engaging wheel axis, but is positioned in front of the associated ground-engaging wheel axis, as seen in the intended direction of movement of the wheelchair, and arranged so that the auxiliary wheel is normally out of contact with the ground.

2. A wheelchair as claimed in claim 1, having a pair of front ground-engaging wheels and a pair of coaxial rear ground-engaging wheels, an auxiliary wheel assembly mounted between the two front wheels, and associated with both front wheels, and single auxiliary wheels associated with each of the rear wheels.

3. A wheelchair as claimed in claim 2, wherein the auxiliary wheel assembly comprises a first auxiliary wheel axis ahead of and above the axes of the front ground-engaging wheels, and a second auxiliary wheel axis above and ahead of the first auxiliary wheel axis.

4. A wheelchair as claimed in claim 2, wherein the auxiliary wheels associated with the rear ground-engaging wheels are of larger diameter than the rear ground-engaging wheels.

5. A wheelchair having a pair of front ground-engaging wheels and a pair of coaxial rear ground-engaging wheels, an auxiliary wheel assembly mounted between the two front wheels, and associated with both front wheels, and an auxiliary wheel associated with each of the rear wheels, each auxiliary wheel being mounted for rotation about an axis which is parallel to the associated ground-engaging wheel axis, but is positioned in front of the associated ground-engaging wheel axis, as seen in the intended direction of movement of the wheelchair, and arranged so that the auxiliary wheels are normally out of contact with the ground, the auxiliary wheels associated with the rear ground-engaging wheels being of larger diameter that the rear ground-engaging wheels, and at least one of the rear ground-engaging wheels being drivingly connected to its associated auxiliary wheel, so that rotation of the auxiliary wheel drives the ground-engaging wheels and the chair.

6. A wheelchair as claimed in claim 5, wherein the auxiliary wheel assembly comprises a first auxiliary wheel axis ahead of and above the axes of the front ground-engaging wheels, and a second auxiliary wheel axis above and ahead of the first auxiliary wheel axis.

7. A wheelchair as claimed in claim 5, wherein the driving connection comprises a chain running over sprocket wheels on the axis of the respective auxiliary and ground-engaging wheels.

8. A wheelchair as claimed in claim 5, wherein said driving connection is provided on each of the rear wheels, and the auxiliary wheels associated with the rear wheels are arranged so that they may be manually rotated by a person sitting in the pushchair.