| 摘要 |
PURPOSE:To enhance the operating easiness by allowing the drive to continue only by separation of the hand even in case it touches a lens barrel undeliberately by furnishing a means to change over a photographing lens driving means into the intermittent drive. CONSTITUTION:When a focusing motor 9 lying in the reset position is put in regular rotating and advances in the optical axis direction (to the left), the first timer is started to commence counting of the drive pulses. If judgement is such that the specified number of pulses is not attained within a certain time, changing-over into the pulse drive (intermittent) and the focusing motor 9 is driven. According to the arrangement, the motor 9 is changed over into the intermittent drive in case the camera user has by mistake stopped the motion of a photographing lens 1 during focusing, or under the focusing return, so that it is free from risk of heat emission of the motor 9 because of flowing of a lock current, allows movement of the lens 2, and enables the focusing movement and the returning motion. |
