A transmission device for a wheelchair with a rehabilitation function includes a first transmission shaft, a second transmission shaft coaxial to the first transmission shaft, and a sliding member. The first transmission shaft includes a first engaging portion. The second transmission shaft includes a driving section. The sliding member is mounted around the driving section to permit synchronous rotation. The sliding member has a second engaging portion and is slideable between a transmission position in which the second engaging portion engages with the first engaging portion and a release position in which the second engaging portion disengages from the first engaging portion. A wheelchair includes two transmission devices associated with two rear wheels and two footrests. The footrests can be actuated when the rear wheels move.

A mobile chair apparatus is described that comprises a drive assembly that preferably includes one or more moveable foot pedals, and drive wheels which rotate in response to rotation of the foot pedals by the mobile chair occupant, and a steering assembly which comprises two steering wheels and at least one tiller, configured such that forward and backward movement of said tiller will translate into movement of both steering wheels, wherein the drive assembly and the steering assembly concurrently enable the mobile chair occupant to propel and steer the mobile chair apparatus without assistance from another person.

A manual wheelchair including a collapsible frame having a first lateral member that is connected to first and second braces at their respective first ends. A drive wheel axel extends along a first axis of rotation and engages a drive wheel, the first brace, and a portion of a transmission. A push rim axel extends along a second axis of rotation and engages a push rim wheel, the second brace, and a portion of the transmission, which transmits rotation of the push rim to rotation of the drive wheel. The collapsible frame additionally includes a second lateral member that is connected to the first and second braces as their respective second ends. The first and second braces are configured to release the second lateral member to collapse the manual wheelchair.

A conveyance to carry humans, such as a wheelchair, is described having levers on each side of the wheelchair that are manually moved forward and backward to propel the conveyance. The user is able to shift into forward, reverse or neutral, brake, and change mechanical advantage (gear ratio), all this without removing the user's hands from the drive levers.

A mobile chair apparatus is described that comprises a drive assembly that preferably includes one or more moveable foot pedals, and drive wheels which rotate in response to rotation of the foot pedals by the mobile chair occupant, and a steering assembly which comprises two steering wheels and two armrests, wherein movement of just one armrest will translate into movement of both steering wheels, and wherein the drive assembly and the steering assembly concurrently enable the mobile chair occupant to propel and steer the mobile chair apparatus without assistance from another person.

An apparatus comprising a steering assembly, a drive assembly and a seat, the steering assembly comprises a first armrest connected to a first link arm, and a second armrest connected to a second link arm; a first tie rod connected to the first link arm and a second tie rod connected to the second link arm; a first steering block connected to the first tie rod and a second steering block connected to the second tie rod; a third tie rod interconnecting the first and second steering blocks; and a first and second steering wheel, and/or the drive assembly comprises a first and second drive wheel connected to an axle; a support shaft; foot pedals connected to a crank; a first chain connecting the crank to a gear hub; and a second chain connecting the gear hub to the axles or connecting components of the gear hub.

A drive mechanism for a wheelchair may include a hand grip having a continuous track that moves over a drive rotator. The hand grip may have a flat, top surface that extends ventrally from the wheelchair. The drive mechanism may include a drivetrain connected to the drive rotator, such that movement of the hand grip in a dorsal or a ventral direction causes the drive rotator to rotate, and such rotation actuates the drivetrain. The drive mechanism may further comprise a switch. When the switch is in a first position, actuation of the drivetrain drives the wheels of the wheelchair. When the switch is in a second position, actuation of the drivetrain drives a mechanism that lifts the wheelchair into a standing position.

Apparatus for a manually-powered wheelchair comprising a frame and first and second wheel rotatably coupled to the frame. Each wheel includes a hand rim and a drive wheel. For each of the first and second wheels, a multiple speed transmission coupled to the wheel comprises a transmission output coupled to the drive wheel, a transmission input coupled to the hand rim, and at least two gears selectively coupling the transmission output to the transmission input. The transmission allows the drive wheel and the hand rim to rotate concentrically with one another but at different speeds. A selector is provided for selecting one of the at least two gears. A controller controls the selector to operate the transmission for the first and/or second wheel.

A geared wheel system for minimizing backlash is functionally coupled to a wheelchair and disclosed herein.

Example embodiments are related to a wheel coupling system for a vehicle. The wheel coupling system according to example embodiments may include a torque transmission element having a rotatable member to generate a torque force and a torque receiver for releasably engaging the torque transmission element. The wheel coupling system may further include a wheel coupled to the torque receiver such that removal of the wheel disengages the torque receiver from the torque transmission element to allow the torque transmission element to remain intact.