| 摘要 |
<p>A change speed gear mechanism comprises a hollow, frusto-conical, rotary shell (6) having rings (12-16) of gear teeth disposed about its internal periphery, an input shaft (2) rotatable relatively to the shell, an output gear (18) fixed to the shell, and a change gear unit (19) mounted internally of the shell for cooperation with the gear rings on the shell. The change gear unit (19) is coupled to the input shaft (2) and is mounted for rotation about an axis parallel to the generatrix of the shell. It comprises a series of gear cages (24-28) associated respectively with the gear rings (12-16) on the shell, each cage including a ring of gear teeth expandable into mesh with the associated gear ring on the shell so as to transmit rotation from a selected gear cage to the shell. The gear cages of the change gear unit are selectively operable to provide different transmission ratios between the input shaft and the output gear.</p> |
