| 摘要 |
<p>A modular high volume digital color printing system using a drop on demand printing mechanism. Each printing module contains at least two heads to allow simultaneous printing of both sides of the paper. Bi-level page image memories are provided. In the preferred configuration, the four pages on a single sheet of paper are printed simultaneously by one printing module. The pages to be printed can be altered by changing the contents of the bi-level page memories, and the system does not require the manufacture of printing plates. The heads are supplied with ink by a gravity feed mechanism from a single ink reservoir for each color. Ink pressure is accurately maintained by regulating ink column height. Paper transport into and out of a printing module is also modular, and is achieved by the incorporation of a modular conveyor belt. The blank paper to be printed is supplied on a roll. This roll is mounted on a frame which can be easily inserted or removed from the printing module when the paper needs to be replenished. The paper roll frame is mounted with wheels to allow it to be simply rolled into or out of the printing module. The paper roll is at floor level, with the paper transport mechanisms being mounted above the roll. The modularity of the system allows all of the sheets in a color publication to be printed and collated simultaneously. A system with one module for each four pages of the publication can print publications at a rate of sixty copies per minute when using LIFT heads which print at one page per second.</p> |
