| 摘要 |
PURPOSE:To prevent the erroneous operation of an opener by providing a switching means which opens so that the opening port will be able to engage with an enlargement means by inserting a disk case and closes so that engagement with the enlargement means will be prevented by taking out. CONSTITUTION:Before inserting a disk case 1, a shutter plate 50 is prevented from being opened by two shutter stoppers 57 even when the plate 50 is pushed by hand, and it is energized in the closing direction at any time by an inversion spring 55. When the plate 50 is inserted, protrusion parts 63 of two shutter stoppers 57 are pushed and rotated by the disk case 1, and therefore, the stopper of the shutter plate 50 is removed, and the plate can be opened or closed. Since the driving force of the inversion spring 55 is in the reverse direction when a guide pin 60 is positioned by the vicinity of the center of a cam groove 54 in this case, the shutter plate 50 changes energization in the opening direction, the disk 1 and the shutter plate 50 do not contact with each other as a result, and inserting load of the disk case due to the shutter plate is eliminated. |
