| 摘要 |
PURPOSE:To obtain a variable power mechanism of a high accuracy by providing a guide member on which a lens frame is placed, and a converting member for moving an optical path converting mirror, on the same guide member, at variable power conversion. CONSTITUTION:In case a copying magnification is converted to the direction of a magnification copying from a state of an unmagnification copying shown in the figure, when cam members 37, 36 are rotated clockwise simultaneously, and stopped at a prescribed angle, a projection lens 30 moves by a prescribed quantity in the right direction by following the curved surface of the cam member 37, and a plate 21 also moves by a prescribed quantity in the left direction by following the curved surface of the cam member 36. In this case, a distance between pulleys 18A, 20A and pulleys 18B, 20B becomes long by a istance in which the plate 21 has moved, a distance between pulleys 17A, 19A and pulleys 17B, 19B becomes short by the same quantity, and a pair of right and left pulleys 11 move in the right direction by 1/2 of a moving extent of the plate 21. As a result, the second mirror unit 6 to which the pulleys have been installed recedes from the first mirror unit 3, and a projection distance extending from the original surface to the peripheral surface of a photosensitive drum is expanded. |
