Driving force transmitting device which disposes gears in a small space and optical unit

摘要

A driving force transmitting device includes a first gear that rotates about the same rotational shaft as that of a small wheel portion and a second gear that engages with the small wheel portion and to which a rotational driving force is transmitted from the first gear. A rib member that rotatably supports the second gear is provided at a rotational center of the second gear. A first end portion of a rotational shaft is pivotally supported by an attachment plate within a root circle of the first gear. The annular rib member is provided on a web face of the first gear. The rib member has the same rotational shaft as the first gear and co-rotates with the first gear while supporting a second end portion of the rotational shaft.

主权项

1. A driving force transmitting device comprising:
a first gear that is rotated by a rotational driving force transmitted from a driving force generating device, the first gear having a small wheel portion provided integrally in a root circle and rotating about the same rotational shaft as that of the small wheel portion; and a second gear that engages with the small wheel portion of the first gear and to which a rotational driving force is transmitted from the first gear, wherein: a rotation support member that rotatably supports the second gear is provided at a rotational center of the second gear; a first end portion of the rotation support member is disposed in a device main body of the driving force transmitting device, in the root circle of the first gear; and an annular rib member is provided on a web face of the first gear, the rib member having the same rotational shaft as the first gear and corotating with the first gear while supporting a second end portion of the rotation support member disposed in the device main body.