Patent ID: 6408961
Filing Date: 2002-06-25
Classification: A61G,B60K,B60L,B60Y,Y10S

Abstract:
An apparatus for driving electrically a hand-operated wheelchair, the wheelchair including a chair frame that has two vertical rod portions, and two axle holes that are formed through the rod portions, respectively, and two wheels that are mounted rotatably on two opposite sides of the chair frame, each of the wheels having a hub which has two opposite sides, each of which is provided with a plurality of pairs of spokes that extend therefrom, the hub and each pair of the spokes defining cooperatively a generally triangular space thereamong in a respective one of the wheels, said apparatus comprising:two driving devices each of which includes a motor unit that is provided with a motor shaft, and a transmission unit that is adapted to be mounted removably on a respective one of the wheels so as to transfer rotation of said motor shaft to the respective one of the wheels in such a manner that each of the wheels rotates at a speed smaller than that of the respective motor shaft; a power supply device adapted to be disposed on the chair frame for supplying electrical power to said motor units of said driving devices; and a control device which controls speed ratios of said motor shafts of said motor units of said driving devices so as to be adapted to steer the wheelchair; wherein said transmission unit of each of said driving devices is provided with a reduction gearing, each of said driving devices further including: a vertical disk; a fastener unit adapted to attach said disk removably to the chair frame; and a housing disposed removably on said disk so as to house the respective reduction gearing therein, thereby retaining the respective reduction gearing between said disk and said housing; wherein said fastener unit of each of said driving devices includes:a horizontal threaded rod fixed to said disk at an end thereof and adapted to extend through a respective one of the axle holes in the chair frame; an annular first clamping block sleeved on said threaded rod and having a curved surface that is adapted to abut against a respective one of the rod portions of the chair frame; two second clamping blocks fixed to said disk one above another, said threaded rod being located between said second clamping blocks, each of said second clamping blocks having a curved surface that is adapted to abut against a respective one of the rod portions of the chair frame so as to clamp the respective one of the rod portions between said first clamping block and said second clamping blocks; and a cross-shaped handle engaging threadably said threaded rod and connected rotatably and non-movably to said first clamping block, assembly of said first clamping block and said handle serving as a lock nut.