| 摘要 |
PURPOSE:To adopt an optional exposure control, by providing a movable coil member for driving a shutter blade and a movable coil member for determining a diaphragm aperture and controlling them so that they are operated in time series. CONSTITUTION:The first and the second movable coil members 6 and 7 are arranged in a laminated layer in the gap between the second yoke 3 and a permanent magnet 4, and an aperture shutter blade 14 is provided between the second yoke 3 and a holding plate 15. Normally, the first movable coil member 6 is so held that a pin 10a of a control lever 10 is placed in the middle point of a cam groove 8; but, the can groove 8 is operated preliminarily to place the pin 10a on the open side of F2.8, and the speed is changed by the variance of the duration of conduction and a current value to control the manipulated variable of the second movable coil member 7, and both movable coil members are operated in time series, thereby performing optionally the aperture and seconds combination automatic exposure control and other control operations. |
