| 摘要 |
<p>The device for identifying registering marks in colour printing includes two reading heads (30 and 31) connected by an amplifier (32) to an analyzing device (33) to treat the information read on the web (2) running over an engraved cylinder (38). An angular encoder (37) calculates the angular posi-tion of the engraved cylinder (38) while it rotates, and transmits it to the analyzing device (33) which memorizes the received information from case to case. The analyzing device (33) also sends out a signal (36), in order to control the idler roller (41) creating a positive or negative elongation of the web (2) between two points (47, 48) of it. The elongation, thus achieved, allows the identification of the registering marks, by comparing the two different registering mark reading results.</p> |
