| 摘要 |
Illustrative embodiments of ratchet tools are disclosed. In at least one embodiment, a ratchet tool may comprise an output shaft, a motor, and a transmission coupled between the output shaft and the motor. The transmission may comprise a ratchet mechanism and a speed-sensitive clutch. The speed-sensitive clutch may be configured to (i) connect the output shaft to the motor when the motor provides rotation to the transmission above a predetermined speed so that the output shaft is driven by the motor and (ii) disconnect the output shaft from the motor when the motor does not provide rotation to the transmission above the predetermined speed so that the output shaft is free to be rotated manually without resistance from the motor. |
