| 摘要 |
PURPOSE:To control a movable member without spreading the influence of a trouble, by judging as abnormality when driving pulses of a prescribed number are given to a pulse motor driving circuit and the movable member does not reach a prescribed position. CONSTITUTION:A lens supporting table 506 equipped with a zoom lens 20 is fitted to the shaft of a pulse motor 501 through a wire 503 and pulleys 504 and 504. The focussing of the lens 20 can be performed by moving the lens 20 by normally and reversely rotating the motor 501. When driving pulses of a prescribed number are given to a pulse motor driving circuit and the lens 20 does not reach a prescribed position, it is judged that an abnormal condition occurs. In addition, it is also possible to judge whether or not the position of a paper size control plate, etc., controlled by the pulse motor 501 is normal in the same way as applied to the lens. |
