| 摘要 |
PURPOSE:To drive a lens barrel and control its position, and to improve the reliability by inputting pulses whose number corresponds to subject distance to a solenoid, and rotating a ratchet mechanism and driving a lens driving ring. CONSTITUTION:At the time of a shutter button is pressed, a distance measuring circuit calculates the subject distance and supplies pulses whose number corresponds to the distance to the solenoid 23. a plunger 24 is attracted and a feed claw lever 16 draws a ratchet 16 by the number of the supplied pulses through the counterclockwise rotation of a lever 19, thereby placing the lens barrel in an infocus state through the clockwise rotation of the driving ring. When a pin 17 kicks up a lever 29 on the end of photography, pins 33 and 34 push up the levers 16 and 28 away from the ratchet 15 and the ring 11 returns its initial position where it contacts a pin 14. Thus, the lens is driven and its position is controlled by the simple structure in which power-feeding control over the solenoid 23 is only performed, thereby improving the reliability. |
