Drive device
A drive device mounted on a vehicle, the drive device comprising: an electric motor housed in the electric motor chamber; a first shaft arranged parallel to or coaxial with a rotor shaft of the electric motor; a counter gear for transmitting rotation of the rotor shaft to the first shaft; a second shaft for rotating wheels of the vehicle; a hypoid gear for transmitting rotation of the first shaft to the second shaft; an oil seal for sealing a gap between the first shaft and the case; a first lubricating oil housed in the electric motor chamber and the counter gear chamber; and a second lubricating oil housed in the hypoid gear chamber.
1 . A drive device mounted on a vehicle, the drive device comprising:
a case including an electric motor chamber, a counter gear chamber, and a hypoid gear chamber, the counter gear chamber and the hypoid gear chamber being separated by a partition wall, and the partition wall having a through-hole;
an electric motor housed in the electric motor chamber;
a first shaft that is disposed parallel to or coaxial with a rotor shaft of the electric motor and extends from the counter gear chamber to the hypoid gear chamber;
a counter gear that is housed in the counter gear chamber and transmits rotation of the rotor shaft to the first shaft;
a second shaft that extends from the hypoid gear chamber to an outside of the case and rotates a wheel of the vehicle;
a hypoid gear that is housed in the hypoid gear chamber and transmits rotation of the first shaft to the second shaft;
an oil seal that seals a gap between an outer peripheral surface of the first shaft and an inner peripheral surface of the through-hole;
a first lubricating oil stored in the electric motor chamber and the counter gear chamber; and
a second lubricating oil stored in the hypoid gear chamber.
2 . The drive device according to claim 1 , wherein a viscosity of the first lubricating oil is lower than a viscosity of the second lubricating oil.
3 . The drive device according to claim 1 , further comprising an oil pump that circulates the first lubricating oil between the electric motor chamber and the counter gear chamber.
4 . The drive device according to claim 1 , wherein:
the rotor shaft has cylindrical configuration;
the rotor shaft includes a first shaft flow path extending along a central axis of the rotor shaft in longitudinal direction; and
the first shaft flow path includes a plurality of first oil discharge ports extending from the first shaft flow path to an outer peripheral surface of the rotor shaft, the plurality of first oil discharge ports being connected to the electric motor chamber and the counter gear chamber.
5 . The drive device according to claim 1 , wherein:
the first shaft has cylindrical configuration;
the first shaft includes a second shaft flow path extending along a central axis of the first shaft in longitudinal direction; and
the second shaft flow path includes a second oil discharge port extending from the second shaft flow path to an outer peripheral surface of the first shaft and connected to the counter gear chamber.
6 . The drive device according to claim 1 , wherein:
the rotor shaft and the first shaft have cylindrical configuration;
the rotor shaft includes a first shaft flow path extending along a central axis of the rotor shaft in longitudinal direction;
the first shaft flow path includes a plurality of first oil discharge ports extending from the first shaft flow path to an outer peripheral surface of the rotor shaft and connected to the electric motor chamber and the counter gear chamber;
the first shaft includes a second shaft flow path extending along a central axis of the first shaft in longitudinal direction; and
the second shaft flow path includes a second oil discharge port extending from the second shaft flow path to an outer peripheral surface of the first shaft and connected to the counter gear chamber.