| 摘要 |
A pneumatic power tool comprises a rotary driven output spindle (21) defining an axis, an air motor (17) having an output shaft (26) axially aligned with the output spindle, transmission means connecting the output shaft and the spindle, and control means (16) for operating the air motor. The transmission means comprises a two speed gear system to provide a first drive having a lower torque output and a second gear reduced drive having a higher torque output and a lower rotary speed output relative to the first drive. The two speed gear system also includes a spindle assembly (35) which is axially translatable between first and second drive positions (34) for biasing the spindle assembly (35) to the first drive position, a collar (37) rotatable about the axis and cam means (38, 39) cooperative between the spindle assembly (35) and the collar (37) to effect axial movement of the spindle assembly (35) between the first and second drive positions. |
