| 摘要 |
In a wheelchair which comprises a pair of drive wheels mounted to a body frame and a front caster wheel and a rear caster wheel mounted to the body frame to the front and rear of the drive wheels so as to allow the wheelchair to turn at a stationary position, a link member extends between the body frame and the drive wheels, and includes one end pivotally connected to an upper part of the body frame and another end rotatably supporting the drive wheel, a rotary shaft of the drive wheels being placed behind a point of connection between the body frame and the link member at least before the front caster wheel abuts a stepped portion of a floor surface. Thus, when the front caster wheel runs into a stepped portion of a floor surface as the wheelchair moves forward, the link member turns around the point of connection between the body frame and the link member so as to reduce the distance between the front caster wheel and the drive wheels while, at the same time, the front end of the body frame tilts upward around the rear caster wheel. The front caster wheel thereby lands on the upper surface of the step, and successfully rides over the step. <IMAGE> |
