公开(公告)号：US3951531A

公开(公告)日：1976-04-20

申请号：US529752

申请日：1974-12-05

申请人： Hiroshi Nakai ,  Tetsuo Nishizawa ,  Ziro Sekine

发明人： Hiroshi Nakai ,  Tetsuo Nishizawa ,  Ziro Sekine

IPC分类号： G03B19/18 ,  G03B1/22 ,  G03B9/10

CPC分类号： G03B1/22 ,  G03B9/10

摘要： A rotary shutter of a motion picture camera comprises a pair of fan-shaped sectors which are capable of changing the angle of opening formed thereby. The sector shaft is rotated through a gear train by a claw driving shaft which in turn is rotated by a driving motor. The gear train comprises a pair of gear train means either of which is selectively used to transmit the rotation of the claw driving shaft to the sector shaft. The ratio of the rate of revolution of one shaft to that of the other is changed by changing the gear train means. A switchover means is provided to switchover the gear train from one to the other. The switchover means is associated with means for changing the angle of opening formed by the sectors. In the mode of the prolonged time exposure, the speed of revolution of the sector is reduced to the half of that of the sector in the mode of the normal motion picture. The claw is caused to be out of engagement with the perforation of the film during every other reciprocal movement of the claw so that the film will remain stationary during every other reciprocal movement of the claw to effect a prolonged exposure time.

摘要翻译： 电影摄像机的旋转快门包括能够改变由此形成的开口角度的一对扇形扇区。 扇形轴通过爪驱动轴通过齿轮系旋转，该爪驱动轴又由驱动电机旋转。 齿轮系包括一对齿轮系，其中任何一个选择性地用于将爪驱动轴的旋转传递到扇形轴。 通过改变齿轮组装置来改变一个轴的转速与另一个轴的转速之比。 提供切换装置以将齿轮系从一个切换到另一个。 切换装置与用于改变扇区形成的开口角度的装置相关联。 在长时间曝光的模式中，在正常运动图像的模式中扇区的转速降低到扇区的转速。 在爪的每隔一个往复移动期间，使爪与胶片的穿孔脱离接合，使得胶片在爪的每隔一个往复移动期间保持静止，以实现长时间的曝光时间。