| 摘要 |
PURPOSE:To eliminate the irregularity of run of a shutter blade part by providing a cam groove part having an arcuate cam groove which engages the 1st and the 2nd engagement projections and corresponds to turning paths of said engagement projections and a linear cam groove connecting with said cam groove. CONSTITUTION:The cam groove part 63 consisting of the linear cam groove 63A which is formed lengthwise in the 1st driving arm 62 from its one end part to the middle part and the arcuate cam groove 63B which connects with said cam groove and also corresponds to the track of an engagement projection 32 implanted in a driving gear 30 is provided to the front surface of the 1st driving arm 62. Then, the engagement projection 32 is allowed to start in ''high-voltage mode'' at a position indicated by a mark 32' and have a long approach run period, or to start at a position indicated by a mark 32'' in ''low-voltage mode'' and has a short approach run period. Consequently, the irregularity of run of the shutter blade part is eliminated. |
