| 摘要 |
<p>PROBLEM TO BE SOLVED: To alleviate impact force and the like when a drive member returns to an exposure operation start position.SOLUTION: Provided are: drive members 40 and 50 that drive blade members 20 and 30; a setting member 100 that sets the drive member at a set position prior to an exposure operation start against urging force; an absorbed member 60 that includes a shaft part 61 movably supported by attachment holding parts 43 and 53 of the drive member, an absorbed part 62 and flange part 63; and an electromagnet 90 that absorbedly holds the absorbed part in a state where the drive member is set to the set position. Between the attachment holding parts 43 and 53 and the absorbed part 62, a first urging spring 70 is arranged that urges the absorbed part toward the electromagnet and between the attachment holding parts 43 and 53 and the flange part 63, a second urging spring 80 is arranged that alleviates an impact when an end of the attachment holding part abuts on the flange. Accordingly, the impact and the like when the drive member is positioned in the exposure operation start position can be alleviated, and the drive member can be surely absorbedly held by the electromagnet.</p> |
