A brake system for a wheelchair comprises a lever assembly adapted to be movably connected to a wheelchair frame, the lever assembly having a handle portion for hand manipulation. A brake unit is adapted to be pivotally connected to relative to the wheelchair frame, the brake unit having a brake end adapted to contact the wheel. An actuator portion and a follower portion are in the brake system, the follower portion cooperating with the actuator portion for the brake unit to be selectively displaceable between at least two configurations, including a floating configuration in which the brake end contacts the wheel so as to automatically pivot into blocking contact with the wheel when the wheel rotates rearwardly, while allowing a forward rotation of the wheel, and a locking configuration in which the brake end is manually locked into blocking contact with the wheel.

There are provided a rear wheel rotatably provided in a body, a seat disposed on a top surface side of the body, a seat link mechanism by which the seat is supported to be movable up and down between a raised position and a lowered position on the top surface side of the body, and a brake mechanism which inhibits the rear wheel from rotating in interlock with the seat link mechanism, when the seat is raised from the lowered position to the raised position.

A wheelchair (100) includes a chassis (101) defining a seat (102), a backrest (103), one or more armrests (104,105), and an undercarriage (106). One or more front caster wheels (118,119) are coupled to, and selectively detachable from, the undercarriage. One or more rear wheel assemblies (120,121) each include a rear wheel (125), an axle (127), and a mounting post (129) extending distally from the axle at a substantially orthogonal angle relative to the axle. One or more quick release devices (130,131) couple each mounting post of each rear wheel assembly to the undercarriage such that the each the one or more rear wheel assemblies is selectively detachable from the undercarriage.

A wheelchair (100) includes a chassis (101) defining a seat (102), a backrest (103), one or more armrests (104,105), and an undercarriage (106). One or more front caster wheels (118,119) are coupled to, and selectively detachable from, the undercarriage. One or more rear wheel assemblies (120,121) each include a rear wheel (125), an axle (127), and a mounting post (129) extending distally from the axle at a substantially orthogonal angle relative to the axle. One or more quick release devices (130,131) couple each mounting post of each rear wheel assembly to the undercarriage such that the each the one or more rear wheel assemblies is selectively detachable from the undercarriage.

Wheelchair drive boost apparatuses, drive assisted wheelchairs, and wheelchair drive boost systems are disclosed. A wheelchair drive boost apparatus includes a housing, a drive wheel including a drive axis that is movable with respect to the housing, a drive lever that engages with the drive wheel to cause the drive wheel to rotate, a transmission that couples the drive lever to the drive wheel, and an engager having a first position and a second position. The engager is configured to move the drive axis with respect to the housing.

Wheelchair drive boost apparatuses, drive assisted wheelchairs, and wheelchair drive boost systems are disclosed. A wheelchair drive boost apparatus includes a housing, a drive wheel including a drive axis that is movable with respect to the housing, a drive lever that engages with the drive wheel to cause the drive wheel to rotate, a transmission that couples the drive lever to the drive wheel, and an engager having a first position and a second position. The drive wheel is coupled to the transmission via a one-way engagement mechanism that permits free rotation of the drive wheel with respect to the drive lever in a first direction and constrains rotation of the drive wheel with respect to the drive lever in a second direction opposite the first direction. The engager is configured to move the drive axis with respect to the housing.

A folding wheelchair which prevents unexpected unfolding includes an upper support arm and a lower support arm coupling a left side frame and a right side frame foldable in an up-down direction in central portions thereof in a left-right direction. An engaged section is provided in at least one of the upper support arm and the lower support arm. An engagement section engages the engaged section to prevent relative displacement in the up-down direction of the central portions of the upper support arm and the lower support arm in the left-right direction. An operation section switches operation of the engagement section from an engagement state with the engaged section to an unengaged state.

A self-locking wheelchair device is disclosed that automatically brakes the wheel when the wheelchair is parked so patients don't have to worry about the wheelchair moving when they get out of the chair. The self-locking wheelchair device comprises a pressure sensitive pad that is configured in a rectangular shape and positioned in a seat of a conventional wheelchair. The pressure sensitive pad is in communication with a control box comprising a battery, a controller, and a motor. The control box is then in communication with at least one automatic brake assembly, such that when a user attempts to stand from a wheelchair, the brakes are automatically engaged. The device also includes a manual brake to override the automatic brake assemblies, as needed and a lock/release lever once the user has risen or been seated within the wheelchair, to disengage the automatic brake assemblies.

Disclosed is a folding wheelchair having a plurality of support members each having a first and a second end, a first separation distance measured between the respective first ends of a second support member and a fourth support member, a second separation distance measured between the respective second ends of the second support member and a fourth support member, a third separation distance measured between the respective first ends of the first support member and the third support member, wherein the wheelchair can be disposed in an open position and a folded position and, in the open position, the first separation distance is shorter than the second separation distance, the first separation distance is shorter than the third separation distance, and the second separation distance is shorter than the third separation distance. An intersection angle of the second and fifth support members is less than 55 degrees.