| 摘要 |
<p>Designed to efficiently effect duplex printing with a single digital printer, a duplex printing apparatus comprises: a pair of feed roll units (6a and 6b) arranged across the digital printer (4) from each other in a direction of travel of a web of paper (3) and each adapted to be driven synchronously with a paper supply and a paper takeup unit (2 and 5) for feeding the web of paper to travel forwards and backwards while an upper surface of the web of paper faces an under surface of the digital printer (4); a turnover unit (16), whereby the traveling web of paper is turned over through, and is allowed to bypass, a turnover path of the turnover unit; a mark sensor (15) arranged upstream in a direction of travel of the web of paper for detecting a timing mark which has been printed by the digital printer on an under surface of the web of paper; and a control unit (7) operable so that on the upper surface of the web of paper there is printed an image corresponding to an image that has been printed on the under surface.</p> |
