| 摘要 |
A system for maintaining registry between a plurality of printing units (102-105), cooperating with a moving web (110), the system being of the type wherein the printing units (102-105) include means, (116, 117, 118, 119) for placing respective registration marks (202, 203, 204, 205, 206) on the web (110), the relative positions of the marks (202, 203, 204, 205, 206) being indicative of registry between the printing units (102-105), and further including means (126) responsive to control signals applied thereto for adjusting the registry of the printing units (102-105), and means for generating control signals to the registry adjusting means (126) in accordance with the relative positions of the registration marks (202, 203, 204, 205, 206). Registration marks (202, 203, 204, 205, 206) include a portion having symmetrical sides diagonal to the direction of the web motion. |
