Collapsible upright wheeled walker apparatus
A collapsible upright wheeled walker with adjustable armrests that support sufficient user upper-body weight to facilitate a natural upright gait and provide unassisted mobility for a wide range of mobility-impaired individuals. The apparatus may be easily and quickly folded (and unfolded) and may include bilateral stabilizing wheel suspensions to facilitate navigation over uneven terrain. The apparatus includes a frame-stiffening folder assembly and may also include mechanical brakes, an adjustable upper armrest assembly with removable padded forearm supports and two pairs of handles, at least one of which is disposed sufficiently forward to place the user within the polygonal footprint defined by the front and rear wheels to provide support without leaning, stooping, or risking falls.
1. A collapsible upright wheeled walker apparatus for augmenting an upright partially-supported walking gait on a walking surface for an unassisted user having one or more hands and forearms, the apparatus comprising:
a frame having two frame sides each having a top and a bottom and each frame side being disposed between a front frame portion and a rear frame portion;
a plurality of wheel assemblies coupled to the frame for supporting the frame above the walking surface and disposed at the vertices of a polygonal footprint on the walking surface within which the user walks during use;
an X-folder apparatus including an anterior element having two ends and a posterior element having two ends, wherein
the anterior element is rotatably coupled to the posterior element,
a first anterior element end is coupled to a first frame side and the second anterior element end is rotatably coupled to an anterior arm having a distal end that is coupled to the second frame side such that rotation of the anterior element in one direction with respect to the anterior arm is limited to an anterior over-center angle, and
a first posterior element end is coupled to the second frame side and the second posterior element end is rotatably coupled to a posterior arm having a distal end that is coupled to the first frame side such that rotation of the posterior element in one direction with respect to the posterior arm is limited to a posterior over-center angle;
two upper supports each coupled to and disposed at an adjustable height above a respective frame side;
two forearm gutters each coupled to a respective upper support for engaging and supporting one user forearm during use, wherein each forearm gutter has a centerline disposed at a first gutter angle with respect to the walking surface and at a second gutter angle with respect to the other forearm gutter centerline;
two upper handles each coupled to a respective upper support anterior to the respective armrest gutter for gripping by one user hand, wherein each upper handle has a centerline disposed at a forward handle angle with respect to the respective forearm gutter centerline; and
in the X-folder apparatus,
an anterior tension adjuster for changing the anterior over-center angle; and
a posterior tension adjuster for changing the posterior over-center angle.
2. The apparatus of claim 1 further comprising:
a foldable frame bridge with two ends each rotatably coupled to a respective frame side.
3. The apparatus of claim 2 further comprising:
a foldable support bridge with two ends each rotatably coupled to a respective upper support.
4. The apparatus of claim 3 wherein:
the anterior and posterior over-center angles each have a value within the range of substantially [1, 10] degrees.
5. The apparatus of claim 4 further comprising:
in each wheel assembly, a rotatably-coupled wheel and a shock absorber assembly coupled between the wheel and the frame for dampening transmission of wheel motion to the frame.
6. The apparatus of claim 5 further comprising:
in each shock absorber assembly, a shock absorber disposed between two ends, one shock absorber end being coupled to the frame and the other shock absorber end being coupled to the wheel, and the shock absorber being pre-loaded to a predetermined load limit.
7. The apparatus of claim 5 further comprising:
in each frame side, three support elements coupled together at to form a triangle.