Patent ID: 8042431

Claim:
A driving force transmitting apparatus, comprising: a first division casing member having a first coupling surface; a second division casing member having a second coupling surface, wherein a casing is formed by matching the first and second casing members at the first and second coupling surfaces; a first rotational shaft rotatably supported by the first and the second division casing members, wherein a center of rotation of the first rotational shaft is located in a common plane of the first and second coupling surfaces; a first gear provided on the first rotational shaft; a second rotational shaft rotatably supported with respect to the first division casing member; a second gear provided on the second rotational shaft and being in mesh with the first gear; a first partition wall integrally formed on the first division casing member and extending in a matching direction of the first and the second division casing members; a second partition wall integrally formed on the second division casing member and extending in the matching direction; a third partition wall crossing the first partition wall and being apart from the common plane of the first and second coupling surfaces in the matching direction; a breather chamber connected with an interior of the casing via a communication port and defined by the first partition wall, the second partition wall, the third partition wall, an outer wall of the first division casing member and an outer wall of the second division casing; and an opening port that connects the breather chamber and an exterior of the casing.