| 摘要 |
PURPOSE:To make it possible to inject dummy droplets only when ink droplets are injected, by judging the necessity and unnecessity of the injection of dummy ink droplets by preliminarily detecting the presence and absence of the injection of ink droplets contributing to real printing. CONSTITUTION:The image information VD from an image information source 10 drives an ink head 1 through a line buffer 11, an OR circuit 13 and a head driving circuit 12. A dummy printing signal forming means 14 allows an AND circuit 15 to take the logical product conjunction of the image information VD and writing signal reversal output WR and outputs detection output DY through the flip-flop 16 of an image information detection circuit 17. The logical product conjunction of the dummy signal DCP generated from a dummy signal source 18, when the head 1 was opposed to an ink adsorbing strip 5 on the basis of a drum reference signal DRP generated at every one rotation of a cylindrical drum 4, is taken by an AND circuit 19 and a dummy printing signal DPP is outputted to the OR circuit 13 and dummy ink droplets are injected from the head 1. |
