Patent ID: 7951038

Claim:
A power transmitting apparatus for performing switching between 2-wheel and 4-wheel drive modes and locking and unlocking a differential mechanism by an operational shaft comprising: an input shaft connected to an engine of a vehicle and rotated around a rotational axis; left and right side output shafts configured to drive front wheels or rear wheels of the vehicle when driving force is transmitted from the input shaft; a differential mechanism arranged between the input shaft and the output shafts and configured to absorb the difference of rotation between the output shafts by differential action thereof; the operational shaft configured to connect and disconnect the input shaft from the output shafts by connecting and disconnecting the input shaft and the output shafts and also configured to lock and unlock the differential mechanism; a driving device configured to drive the operational shaft; and a main case mounted on a vehicle and containing the differential mechanism and the operational shaft therein, wherein the driving device comprises: a reversible motor; a driving shaft rotationally driven by the motor and adapted to be engaged by the operational shaft for transmitting a rotational force therebetween; a sub case containing the motor and the driving shaft therein and mounted on the main case; an opening formed in the sub case and having a size permitting the operational shaft to be inserted and an end face of the driving shaft configured to engage an end face of the operational shaft to be exposed; and a first sealing means arranged on the inner circumferential surface of the opening at a position away from the driving shaft for sealing off the inside of the sub case by forming a seal between the inner circumferential surface of the opening and the outer circumferential surface of the operational shaft when the operational shaft is engaged with the driving shaft.