Patent attributes
A second enclosure is coupled to a first enclosure for relative rotation around a rotation axis. The second enclosure rotates around the rotation axis in the opposite directions from a reference attitude. The second enclosure is prevented from further rotating in the first direction beyond the first rotation angle from the reference attitude. The second enclosure takes the first angular attitude. The second enclosure is also prevented from further rotating in the second direction opposite to the first direction beyond the second rotation angle from the reference attitude. The second enclosure takes the second angular attitude. The displaying unit indicates either of the first and second directions at least when the second enclosure takes the first angular attitude. The displaying unit in this manner enables the user to easily recognize an acceptable direction for the rotation of the second enclosure.
