| 摘要 |
<p>A scanner has a frame assembly (15) containing a carriage (20) movably mounted in the frame assembly (15) for scanning movement in a scanning path in a first direction (33a) along the length of the frame assembly (15), which includes at least one sheet transport path and a roll (35, 42, 46) to index a sheet through the path in a direction transverse to the first direction (33a). The scanning carriage (20) is driven in the scanning path by a lead screw (31) rotatably engaged with the scanning carriage (20) for scanning movement along the length of the lead screw (31) and a reversible motor (32). In a preferred embodiment the scanning carriage (20) supports a reading head (17) and/or a printing head (25) for reading an image on a document (14) and printing an image on a copy sheet (13) and the pitch of the threads (40) of the lead screw (31 ) are selected so than an integer multiple of steps of a stepper motor (32) provides a linear displacement of the carriage (20) of one pixel width and a clock pulse generator simultaneously drives the stepper motor (32) and the reading (17) and/or printing (25) heads. <IMAGE></p> |
