Power transmission device
A unit includes a housing configured to accommodate a planetary gear mechanism, wherein the housing includes a flow path through which a coolant flows, the planetary gear mechanism includes a stepped pinion gear, the stepped pinion gear includes a small pinion and a large pinion, and the flow path has a portion that overlaps the large pinion when viewed in a radial direction.
1. A unit comprising:
a housing configured to accommodate a planetary gear mechanism and an oil, wherein
the housing includes a flow path through which a coolant flows, the coolant is made of a first material different from a second material of the oil,
the planetary gear mechanism includes a stepped pinion gear,
the stepped pinion gear includes a small pinion and a large pinion,
the flow path has a portion that overlaps the large pinion when viewed in a radial direction,
the housing includes a flow path-equipped case including the flow path and a facing case that faces the flow path-equipped case,
the flow path extends in a direction away from a mating surface of the flow path-equipped case and the facing case when viewed in the radial direction,
a carrier of the planetary gear mechanism is connected to an input element of a differential gear mechanism so as to be rotatable integrally therewith,
the differential gear mechanism is accommodated in the facing case, and
the small pinion meshes with a ring gear fixed to the facing case, when viewed in the radial direction.
2. The unit according to claim 1 , wherein
the flow path has a portion that overlaps with a motor when viewed in the radial direction.
3. A unit comprising:
a housing configured to accommodate a planetary gear mechanism and an oil, wherein
the housing includes a flow path through which a coolant flows, the coolant is made of a first material different from a second material of the oil,
the planetary gear mechanism includes a stepped pinion gear,
the stepped pinion gear includes a small pinion and a large pinion,
the flow path has a portion that overlaps the large pinion when viewed in a radial direction,
the unit further comprises a catch tank in the housing,
the catch tank has a portion sandwiched between the flow path and a revolution orbit of the large pinion,
the planetary gear mechanism is accommodated in a gear chamber in the housing, and
the catch tank is located above an oil level in the gear chamber.
4. The unit according to claim 2 , further comprising:
a catch tank in the housing, wherein
the catch tank has a portion sandwiched between the flow path and a revolution orbit of the large pinion.
5. The unit according to claim 1 , wherein
the flow path has a portion through which the coolant flows from above to below.