| 摘要 |
<p>A wheelchair is provided with a helical drive transmission (30). A rectilinear input (60) to the helical drive (30) causes an output gear (55) to rotate, thus providing power to rotate the driving wheels of a wheelchair. The helical drive may include, for example, a compound helix, a drive with a twisted flat bar, or a concentric helix drive. Add on components may be provided to convert a conventional wheelchair powered by a helical drive mechanism (30).</p> |
