摘要 |
The device has a casing (10) comprising a motor (14) and a rotative terminal element (13) connected by a transmission with a gear box (16). The box has a pre-screwing transmission sub-assembly formed by crown, satellite, satellite holder, sun gear, one-way clutch, rotor, runner, axle, bell and output shaft and a screwing transmission sub-assembly formed by one-way clutch and toothed wheel. The clutches are alternatively installed by reversing rotation direction of the motor to rotate the element in alternate direction according to speed. One of the clutches is secured to the casing. |