Disclosed is a wheel chair capable of going over an obstacle or ascending
or descending a stair. The wheel chair comprises a wheel frame; an actuator coupled
to the wheel frame; a power generating unit coupled to the actuator; a first transmission
having a sun gear fixed to the power generating unit, a plurality of planet gears
meshed with the sun gear, a ring gear meshed with the respective planet gears,
and carriers coupled to the respective planet gears; a second transmission having
a driving shaft meshed with the ring gear, a key frame rotatably installed on the
driving shaft, and a casing fixed to the key frame; a plurality of front wheels
each coupled to the driving shaft; a follower drivingly coupled to the driving
shaft and having a follower shaft; and a rear wheel fixed to the follower shaft.
