| 摘要 |
PURPOSE:To make a rotationally driving source inexpensive and an electric circuit which controls the rotation simple, by transmitting a rotationally driving force to an exposure controlling mechanism and focus adjusting mechanism through a differential gear mechanism and, at the same time, driving either one of both mechanisms by selectively changing the loads applied to both mechanisms. CONSTITUTION:When a motor 40 starts rotation, an output gear 20 rotates and, accordingly, a large-diameter gear 21 and small-diameter gear 21a rotate in one direction. The rotation of the gear 21 is transmitted to the internal teeth 24a of an internal gear 24 through the small-diameter gear 21a and planet gears 23, 23, and 23. At the time of the transmission, all the rotations of the large-diameter gear 21 and small-diameter gear 21a are transmitted to the internal gear 24. The rotation of the internal gear 24 is transmitted to an AE cam gear 30. Since the planet gears make revolutions when the rotation of the internal gear 24 is interrupted, all the rotations of the large- and small- diameter gears 21 and 21a are transmitted to a large-diameter gear 22 and the rotation of the gear 22 is transmitted to an AF cam stopper 34 and AF gear 35 through the front gear 33a of an AF cam gear 33. |
