Patent ID: 7039311

Claim:
A rotation transfer mechanism comprising: a rotatable ring comprising an annular gear portion on an outer peripheral surface of said rotatable ring, said rotatable ring configured to perform an advancing/retracting operation in which said rotatable ring moves along a first rotational axis while rotating about said first rotational axis in a first range of rotation of said rotatable ring, and further configured to perform a fixed-position rotating operation in which said rotatable ring rotates without moving along said first rotational axis in a second range of rotation of said rotatable ring; a rotation transfer gear configured to rotate about a second rotational axis parallel to said first rotational axis, said rotation transfer gear including a gear portion engageable with said annular gear portion and a rotation limit portion engageable with an outer edge of said annular gear portion to prohibit said rotation transfer gear from rotating, said gear portion and said rotation limit portion located at different axial positions on said rotation transfer gear; and at least one driven member drivable by a rotation of said rotation transfer gear, wherein said rotation transfer gear and said rotatable ring are positioned relative to each other such that said gear portion and said annular gear portion are engaged with each other when said rotatable ring performs said fixed-position rotating operation, and wherein said rotation transfer gear and said rotatable ring are positioned relative to each other such that said rotation limit portion faces said annular gear portion and is configured to contact said outer edge of said annular gear portion when said rotatable ring performs said advancing/retracting operation.