Patent ID: 8302506

Claim:
A power transmission device comprising: a casing having an inside storing an oil; a rotating body provided rotatably in said casing in direct contact with stored oil and rotating while carrying up a portion of said stored oil; and a partition wall partitioning the inside of said casing into a rotating body housing containing said rotating body and an oil storing chamber capable of receiving said oil carried up by said rotating body, being adjacent to said rotating body housing, and located lower than a rotational axis of said rotating body, wherein said partition wall defines a feed opening for feeding the oil into said oil storing chamber, said feed opening being defined lower in position than the rotational axis of said rotating body, an inner wall of said casing includes a down-extending portion and a receding portion, said down extending portion extends down toward said feed opening and, as said down-extending portion runs downward, said down-extending portion extends toward said rotating body rather than along a virtual vertical plane extending in a vertical direction, and said receding portion borders on said down-extending portion and extends away from said rotating body from a bordering point where said receding portion and said down-extending portion border on each other, said partition wall includes an opening-defining wall portion located directly below said bordering point where said down-extending portion and said receding portion border on each other, and defining said feed opening together with a part of said inner wall where said bordering point is located, and said opening-defining wall portion extends upward and extends away from said rotating body from a part located directly below said bordering point.