Power transmission device
A power transmission device includes a motor, a planetary gear mechanism having a portion that overlaps the motor in an axial direction, an axial direction wall part having a portion positioned between the planetary gear mechanism and the motor, a plate provided between the axial direction wall part and a pinion gear having the gear mechanism, and a box in which the motor, the planetary gear mechanism, the axial direction wall part, and the plate are housed. The box defines a breather hole that communicates with a breather chamber. The box has a radial direction wall part having a portion positioned between the plate and the breather chamber in a radial direction. The plate has a portion positioned between the pinion gear and the breather hole.
1. A power transmission device comprising:
a motor;
a planetary gear mechanism having a portion that overlaps the motor in an axial direction;
an axial direction wall part having a portion positioned between the planetary gear mechanism and the motor;
a plate provided between the axial direction wall part and a pinion gear of the gear mechanism; and
a box in which the motor, the planetary gear mechanism, the axial direction wall part, and the plate are housed, wherein
the box defines a breather hole that communicates with a breather chamber,
the box has a radial direction wall part having a portion positioned between the plate and the breather chamber in a radial direction, and
the plate has a portion positioned between the pinion gear and the breather hole.
2. The power transmission device according to claim 1 , wherein
the breather hole is constituted by a notch part provided on a top part of the box, and the axial direction wall part.
3. The power transmission device according to claim 1 , wherein
the pinion gear has a large pinion gear and a small pinion gear, and
the plate has a portion positioned between the large pinion gear and the breather hole.
4. The power transmission device according to claim 3 , wherein
the planetary gear mechanism has a ring gear that engages with the small pinion gear,
the box has the breather chamber above a revolution orbit of the large pinion gear, and
the box has a roof part projecting in the axial direction between the breather chamber and the revolution orbit of the large pinion gear.
5. The power transmission device according to claim 4 , wherein
the plate has a hook part projecting in the axial direction, and positioned between the roof part and the revolution orbit of the large pinion gear.
6. The power transmission device according to claim 2 , wherein
the pinion gear has a large pinion gear and a small pinion gear, and
the plate has a portion positioned between the large pinion gear and the breather hole.
7. The power transmission device according to claim 6 , wherein
the planetary gear mechanism has a ring gear that engages with the small pinion gear,
the box has the breather chamber above a revolution orbit of the large pinion gear, and
the box has a roof part projecting in the axial direction between the breather chamber and the revolution orbit of the large pinion gear.
8. The power transmission device according to claim 7 , wherein
the plate has a hook part projecting in the axial direction, and positioned between the roof part and the revolution orbit of the large pinion gear.