| 摘要 |
<p>A shutter plate that is supported so as to be able to swing in both directions and covers both first and second operating parts, and a shutter mechanism that operates the shutter plate in one direction when the first operating part is to be exposed and in reverse direction when the second operating part is to be exposed are provided, wherein the shutter mechanism includes one pair of locking members for limiting or releasing the swing of the shutter plate.</p> |
