| 摘要 |
PURPOSE:To simplify a device structure and to reduce a manufacturing cost by controlling the operation of a power transmission means according to an image forming magnification, and moving an optical means to a position, which corresponds with the image forming magnification, through the use of a driving means for driving an exposure scanning means. CONSTITUTION:First and second carriages, provided with an exposure lamp, a mirror, etc., are reciprocated via a pulley 38 and a belt 40 both of which are provided on a shaft 37 rotated by a pulse motor 33. The shaft 37 is provided with first and second clutch parts 51 and 52 aparting with the prescribed distance; a third carriage 313, in which a variable power lens block 8 and an optical path folding mirror are placed via the clutch parts 51 and 52, is moved to a specified copying magnification position via screw shafts 52k and 51k. The third carriage 313 and the variable power lens block 8 can move via the clutch parts 51 and 52 by means of the pulse motor 33 driving the first and second carriage, and therefore the structure can be simplified without requiring a driving motor additionally. |
